LandMark 60 IMU (Inertial Measurement Unit) Technical User ... · LandMark™ 60 IMU (Inertial...

LandMark™ 60 IMU (Inertial Measurement Unit)

Technical User’s Guide

Technical Support

Gladiator Technologies

Attn: Technical Support

8020 Bracken Place SE

Snoqualmie, WA 98065 USA

Tel: 425-396-0829 x222

Fax: 425-396-1129

Email: [email protected]

Web: www.gladiatortechnologies.com

mailto:[email protected]

http://www.gladiatortechnologies.com/

LandMark™ 60 IMU User’s Guide Page i Rev. 09/13/2017 Copyright © 2017 Gladiator Technologies

1 TABLE OF CONTENTS

1 TABLE OF CONTENTS .................................................................................................................. i

2 TABLE OF FIGURES .................................................................................................................... iv

3 SAFETY AND HANDLING INFORMATION ......................................................................................1

4 GETTING STARTED .....................................................................................................................1

4.1 RS422/RS485 TO USB POWER SUPPLY & CONVERTER CABLE .................................................... 2

4.2 LANDMARK™ 60 IMU MATING CONNECTOR ............................................................................ 3

4.3 STOP! READ THIS FIRST........................................................................................................ 4

4.4 INSTALLING THE LINX SDM-USB-QS-S DRIVERS MADE SIMPLE .............................................. 4 4.4.1 Introduction ...............................................................................................................4 4.4.2 Installing the Direct Drivers ........................................................................................6

4.5 GLAMR SOFTWARE INSTALLATION ........................................................................................... 9

4.6 SELECT APPLICABLE BAUD RATE ............................................................................................ 12

4.7 SELECT APPLICABLE STOP BITS .............................................................................................. 14

4.8 SELF-TEST IN GLAMR .......................................................................................................... 15

4.9 SETTING THE MODE AND DATA RATE ..................................................................................... 16 4.9.1 Set IMU Mode 500 Hz Data Rate .............................................................................. 16

4.10 UNIT DISPLAY OPTIONS ....................................................................................................... 18

4.11 DATA RECORD FEATURE ...................................................................................................... 20

4.12 BANDWIDTH FILTERING CAPABILITY ....................................................................................... 22

4.13 CANBUS DBC FILE ........................................................................................................... 25

5 PATENT AND TRADEMARK INFORMATION ................................................................................ 25

6 APPLICABLE EXPORT CONTROLS ............................................................................................... 26

7 USER LICENSE........................................................................................................................... 26

8 STANDARD LIMITED WARRANTY .............................................................................................. 26

9 QUALITY MANAGEMENT SYSTEM ............................................................................................. 26

10 THEORY OF OPERATION ........................................................................................................... 27

11 LandMark™ 60 IMU PRODUCT DESCRIPTION ............................................................................. 29

11.1 OUTLINE DRAWING AND 3D SOLID MODELS ........................................................................... 30 11.1.1 3D Solid Model......................................................................................................... 30 11.1.2 Outline Drawing ...................................................................................................... 31

11.2 OUTLINE EXPLODED VIEW & AXIS ORIENTATION ...................................................................... 32

11.3 CENTER OF GRAVITY ........................................................................................................... 33

11.4 IMU BLOCK DIAGRAM ........................................................................................................ 34

LandMark™ 60 IMU User’s Guide Page ii Rev. 09/13/2017 Copyright © 2017 Gladiator Technologies

11.5 LANDMARK™ 60 IMU PART NAMING CONVENTION & PART NUMBERS ....................................... 35

11.6 LANDMARK™ 60 IMU PIN ASSIGNMENTS .............................................................................. 36

11.7 LANDMARK™ 60 IMU PERFORMANCE SPECIFICATION .............................................................. 37

12 LandMark™ 60 IMU MESSAGE PROTOCOL (V72) ........................................................................ 37

12.1 SERIAL COMMUNICATION SETTINGS ....................................................................................... 37

12.2 IMU MESSAGE PACKET FORMAT .......................................................................................... 37 12.2.1 Important Messaging Protocol Notes ....................................................................... 38

12.2.1.4.1 Message Counter set to 2 – 246, Bit 6 = 0 ............................................................................................ 38 12.2.1.4.2 Message Counter set to 2 – 246, Bit 6 = 1 ............................................................................................ 39 12.2.1.4.3 Message Counter set to 0 or 1 .............................................................................................................. 39 12.2.1.4.4 Message Counter set to 247 (AHRS) ..................................................................................................... 39 12.2.1.4.5 Message Counter Set to 248 – 251 ....................................................................................................... 40 12.2.1.4.6 Board Number Encoding ....................................................................................................................... 40 12.2.1.4.7 Serial Number when Message Counter set to 252 – 255. .................................................................... 41

12.3 SAMPLE DATA FORMAT ....................................................................................................... 44 12.3.1 CAN Output Messages.............................................................................................. 45

12.4 SYNC INPUT (5 KHZ) ........................................................................................................... 45 12.4.1 Specification ............................................................................................................ 45 12.4.2 Status Bit ................................................................................................................. 46 12.4.3 Timing Diagram ....................................................................................................... 46 12.4.4 Bit Values for External Sync Input ............................................................................. 47

12.5 BANDWIDTH VS. NOISE ....................................................................................................... 47

13 SAMPLE TEST DATA & TEST METHODS ...................................................................................... 49

13.1 GLADIATOR ATP EXPLANATION ............................................................................................ 49 13.1.1 Rate Spin Test .......................................................................................................... 49 13.1.2 Accelerometer Tumble Test ...................................................................................... 50

13.2 ANGLE RANDOM WALK ....................................................................................................... 51

13.3 VELOCITY RANDOM WALK ................................................................................................... 52

13.4 BIAS IN-RUN ..................................................................................................................... 53

13.5 BIAS AND SCALE FACTOR OVER TEMPERATURE ......................................................................... 59 13.5.1 Gyro Bias over Temperature ..................................................................................... 59 13.5.2 Gyro Scale Factor over Temperature ......................................................................... 62 13.5.3 Accelerometer Bias over Temperature ...................................................................... 65 13.5.4 Accelerometer Scale Factor over Temperature .......................................................... 68

13.6 BIAS TURN-ON (FROM A COLD START) ................................................................................... 71

13.7 RANDOM VIBRATION .......................................................................................................... 77 13.7.1 Random Vibration .................................................................................................... 77 13.7.2 Sine Vibration Test ................................................................................................... 78 13.7.3 Gyro Sine Vibration Response ................................................................................... 78 13.7.4 Accelerometer Sine Vibration Response .................................................................... 79

14 MOUNTING ............................................................................................................................. 81

LandMark™ 60 IMU User’s Guide Page iii Rev. 09/13/2017 Copyright © 2017 Gladiator Technologies

15 OPERATION & TROUBLESHOOTING .......................................................................................... 81

15.1 TECHNICAL ASSISTANCE ....................................................................................................... 81

15.2 AUTHORIZED DISTRIBUTORS AND TECHNICAL SALES REPRESENTATIVES ......................................... 81

15.3 TECHNICAL SUPPORT WEBSITE .............................................................................................. 82

16 GLOSSARY OF TERMS ............................................................................................................... 86

16.1 ABBREVIATIONS AND ACRONYMS .......................................................................................... 86

16.2 DEFINITIONS OF TERMS ....................................................................................................... 86

LandMark™ 60 IMU User’s Guide Page iv Rev. 09/13/2017 Copyright © 2017 Gladiator Technologies

2 TABLE OF FIGURES

Figure 1 SDK to PC cabling with CAN bus, SDK Power Control/Self-Test, 9 V Battery Connector . 2

Figure 2 Unit Connector .................................................................................................................. 3

Figure 3 Read Me First Installation Guide ...................................................................................... 4

Figure 4 SDK Installation CD ............................................................................................................ 4

Figure 5 Files on Installation Disk ................................................................................................... 5

Figure 6 Driver Setup Wizard .......................................................................................................... 6

Figure 7 License Agreement Prompt .............................................................................................. 7

Figure 8 Installation Folder Prompt ................................................................................................ 7

Figure 9 Driver Package Information Prompt ................................................................................. 8

Figure 10 Driver Installation Status................................................................................................. 8

Figure 11 Glamr Location on SDK CD-ROM .................................................................................... 9

Figure 12 Glamr Software Shortcut Icon ........................................................................................ 9

Figure 13 Glamr Screen before Selecting Correct COM Port Settings .......................................... 10

Figure 14 Confirmed Correct LINX Port with Message "Success" ................................................ 11

Figure 15 Baud Rate Selection for 1000 Hz Data Rate .................................................................. 12

Figure 16 IMU Data in Full Mode at 1000 Hz Data Rate ............................................................... 13

Figure 17 Stop Bit Selection for COM Port ................................................................................... 14

Figure 18 Power and Self-Test Momentary Switch ...................................................................... 15

Figure 19 Self-Test Display When Activated ................................................................................. 15

Figure 20 Mode Selection / Data Rate .......................................................................................... 16

Figure 21 IMU Mode at 500 Hz Data Rate .................................................................................... 17

Figure 22 Gyro Units of Measure Selection Options .................................................................... 18

Figure 23 Accelerometer Units of Measure Selection Options .................................................... 19

Figure 24 Data Record Capability.................................................................................................. 20

Figure 25 Start Record File Path ................................................................................................... 21

LandMark™ 60 IMU User’s Guide Page v Rev. 09/13/2017 Copyright © 2017 Gladiator Technologies

Figure 26 Saving Data Record Time .............................................................................................. 22

Figure 27 Select Desired Bandwidth Filter from Drop-Down Menu............................................. 23

Figure 28 Message Options for Troubleshooting ......................................................................... 24

Figure 29 CANBUS DBC File Generation ....................................................................................... 25

Figure 30 LandMark™ 60 IMU with Mating Connector vs. 2 Euro Coin & US Quarter ................. 28

Figure 31 LandMark™ 60 IMU vs. 2 Euro Coin ............................................................................... 29

Figure 32 LandMark™ 60 IMU 3D Model ....................................................................................... 30

Figure 33 LandMark™ 60 Outline Drawing .................................................................................... 31

Figure 34 LandMark™ 60 IMU Exploded Outline Drawing (metric in [mm]) ................................. 32

Figure 35 LandMark™ 60 IMU Block Diagram ............................................................................... 34

Figure 36 Gladiator Technologies Part Naming Convention ........................................................ 35

Figure 37 LandMark™ 60 IMU Part Number Configurations ......................................................... 35

Figure 38 LandMark™ 60 IMU Pin Assignments and Outputs ....................................................... 36

Figure 39 Serial Communication Settings ..................................................................................... 37

Figure 40 IMU Message Packet Format ........................................................................................ 37

Figure 41 Status Byte Decode when Bit 6 is 0 .............................................................................. 38

Figure 42 Status Byte Decode when Bit 6 set to 1 (every other message) .................................. 39

Figure 43 IMU Status Byte Decode when Message Count set to 0 or 1 ....................................... 39

Figure 44 Status Byte Decode when Message Count set to 247 .................................................. 39

Figure 45 Status Byte Decode when Message Count set to 248 through 251 ............................. 40

Figure 46 Board Number Encoding (32-bit to 6-bit) ..................................................................... 40

Figure 47 Status Byte Decode when Message Count set to 252 through 255 ............................. 41

Figure 48 Gyro LSB Scale Factor .................................................................................................... 42

Figure 49 Accel LSB Scale Factor ................................................................................................... 42

Figure 50 Screenshot of LandMark™ 60 IMU Sample Data ........................................................... 44

Figure 51 IMU CAN Output ........................................................................................................... 45

Figure 52 2.5 kHz Timing Diagram ................................................................................................ 46

LandMark™ 60 IMU User’s Guide Page vi Rev. 09/13/2017 Copyright © 2017 Gladiator Technologies

Figure 53 Bit Values for External Sync Input ................................................................................. 47

Figure 54 Bandwidth Frequency and Output Data Rate ............................................................... 47

Figure 55 Gyro Bandwidth vs. Peak-to-Peak Noise 100 Hz .......................................................... 48

Figure 56 Gyro Bandwidth vs. Peak-to-Peak Noise 1 kHz ............................................................. 48

Figure 57 Rate Spin Test ............................................................................................................... 49

Figure 58 Accelerometer Tumble Test Data ................................................................................. 50

Figure 59 Angle Random Walk (ARW) .......................................................................................... 51

Figure 60 Velocity Random walk ................................................................................................... 52

Figure 61 X Gyro Bias In-Run ......................................................................................................... 53

Figure 62 Y Gyro Bias In-Run ......................................................................................................... 54

Figure 63 Z Gyro Bias In-Run ......................................................................................................... 55

Figure 64 X Accelerometer Bias In-Run ........................................................................................ 56

Figure 65 Y Accelerometer Bias In-Run ......................................................................................... 57

Figure 66 Z Accelerometer In-Run Bias ......................................................................................... 58

Figure 67 X Gyro Bias over Temperature ...................................................................................... 59

Figure 68 Y Gyro Bias over Temperature ...................................................................................... 60

Figure 69 Z Gyro Bias over Temperature ...................................................................................... 61

Figure 70 X Gyro Scale Factor over Temperature ......................................................................... 62

Figure 71 Y Gyro Scale Factor over Temperature ......................................................................... 63

Figure 72 Z Gyro Scale Factor over Temperature ......................................................................... 64

Figure 73 X Accelerometer Bias over Temperature ...................................................................... 65

Figure 74 Y Accelerometer Bias over Temperature ...................................................................... 66

Figure 75 Z Accelerometer Bias over Temperature ...................................................................... 67

Figure 76 X Scale Factor over Temperature.................................................................................. 68

Figure 77 Y Scale Factor over Temperature .................................................................................. 69

Figure 78 Z Accelerometer Scale Factor over Temperature ......................................................... 70

Figure 79 X Gyro Bias Turn-On ...................................................................................................... 71

LandMark™ 60 IMU User’s Guide Page vii Rev. 09/13/2017 Copyright © 2017 Gladiator Technologies

Figure 80 Y Gyro Bias Turn-On ...................................................................................................... 72

Figure 81 Z Gyro Bias Turn-On ...................................................................................................... 73

Figure 82 X Accelerometer Bias Turn-On ...................................................................................... 74

Figure 83 Y Accelerometer Bias Turn-On ...................................................................................... 75

Figure 84 Z Accelerometer Bias Turn-On ...................................................................................... 76

Figure 85 Random Vibration Test Data ......................................................................................... 77

Figure 86 X Gyro Sine Vibration Response ................................................................................... 78

Figure 87 Y Gyro Sine Vibration Response .................................................................................... 78

Figure 88 Z Gyro Sine Vibration Response .................................................................................... 79

Figure 89 X Accelerometer Sine Vibration Response ................................................................... 79

Figure 90 Y Accelerometer Sine Vibration Response ................................................................... 80

Figure 91 Z Accelerometer Sine Vibration Response.................................................................... 80

Figure 92 Website – Select Product Category .............................................................................. 82

Figure 93 LandMark™ 60 IMU Product Main Webpage ................................................................ 83

Figure 94 LandMark™ 60 IMU Product Documentation Downloads ............................................ 83

Figure 95 Remote Desktop Support Web Page ............................................................................ 84

Figure 96 Web Conferencing Web Page ....................................................................................... 85

LandMark™ 60 IMU User’s Guide Page 1 Rev. 09/13/2017 Copyright © 2017 Gladiator Technologies

3 SAFETY AND HANDLING INFORMATION Always use caution when using the LandMark™ 60 IMU!

Supplying too high an input voltage could permanently damage the unit. Input Power is specified at +7.0 V to +36 V Maximum. The unit can withstand input power up to +60 V without damaging the unit, but may not perform within specification.

The LandMark™ 60 IMU is a sensitive scientific instrument containing shock and vibration sensitive inertial and other sensors. Excessive shock and/or vibration can damage these sensors and can adversely affect sensor performance and unit output.

Avoid exposure to electrostatic discharge (ESD). Observe proper grounding whenever handling the LandMark™ 60 IMU.

Properly attach connector and ensure that it has been wired correctly before applying power to the LandMark™ 60 IMU.

4 GETTING STARTED This section contains directions and references for a quick start to using the LandMark™ 60. For additional support, please contact the distributor representing your location. If there isn't a local representative for your location, please contact our Headquarter office for assistance and someone from our Sales Team will assist you. The LandMark™ 60 IMU Software Development Kit (SDK) is an optional product to assist first-time users of the LandMark™ 60 IMU. This kit provides the user everything they need to facilitate a rapid setup and test of the unit. The SDK (P/N SDK-IMU-CANBUS-1) includes display software with user defined options including the following components and is seen in Figure 1:

Turn-Key Solution for LandMark™ 60 IMU on User PC

All Cabling, Interface Connectors and Software Included and Ready for Use

Easy Integration of Direct IMU RS422/RS485 to PC’s USB Port

Includes PC Display Software for IMU

Data Record Capability

Multiple User Selected Field Options for Programming and Initializing the Unit

User Defined Bandwidth Settings and Data Output Rate on IMU

Battery-Powered Power Supply (9V, 1.5 Hours Typical)

Self-Test Switch


Figure 1 SDK to PC cabling with CAN bus, SDK Power Control/Self-Test, 9 V Battery Connector

The following steps will allow the user to quickly set up a LandMark™ 60 IMU and interface it with its SDK.

1. Connect all units together per the User Guide under this section (Getting Started) to the PC. Do

not turn on the power yet. Follow all steps in Section 4 carefully.

2. Follow the instructions from the enclosed disc under Linx SW labeled “STOP! Read This First -

Installation Guide” to load the VCP drivers for the USB interface.

3. Copy the Glamr.msi software and setup.exe applications to the PC hard drive from the header

file on the disc.

4. Run the Glamr.msi to install the Glamr and select the com port to LINX if not selected.

5. Apply power to the unit to see data on the screen. Turn the self-test switch to ON to see a

change in the sensor data that ensures the unit is functioning. Then switch OFF.

6. Follow the instructions in the following sections of the User Guide Glamr Software Installation

(Section 4.5) to change any factory settings for your application.

4.1 RS422/RS485 to USB Power Supply & Converter Cable Contained in the Software Development Kit (SDK) is a complete RS422/RS485 to USB Converter cable including battery powered power supply and self-test switch (Fig. 1). The power supply uses a 9 V battery (included with shipment). Typically when using new batteries, the battery pack will provide the user with approximately one hour of usage before needing to be replaced.


CAUTION: As the battery life declines, the user can experience a voltage drop below the minimum +6 V required. If this occurs, the user can then start to get CHECKSUM errors in the data. It is highly recommended to replace the batteries in the SDK before each field test.

An RS422/RS485 to USB converter (it requires additional drivers that are included in a CD-ROM) is also included. This power supply converter cable and self-test switch enables the user to quickly connect the LandMark™ 60 IMU to their PC to ease integration and testing. Connect the cables to the unit and the converter board to the PC with the USB cable. You do not need to turn on the power switch yet until the rest of the software is installed.

Figure 2 Unit Connector

4.2 LandMark™ 60 IMU Mating Connector The LandMark™ 60 IMU mating connector and mating pins are contained in a separate package to enable customer-specific wiring options. If the SDK was purchased, then the customer also has an RS422/RS485 Converter board, USB connector, and mating pins.


4.3 STOP! Read This First

Figure 3 Read Me First Installation Guide

4.4 Installing the LINX SDM-USB-QS-S Drivers MADE SIMPLE

4.4.1 Introduction The LINX SDM-USB-QS-S module requires that device drivers be installed on the host PC before they can interact. The drivers tell the PC how to talk to the module. These drivers are for Windows 98, XP, NT, Windows 7, and Windows 8. For Windows 10 installation, please see the note. The set for Windows are the direct drivers, which offer program functions that allow a custom application to directly control the module through the USB port.

You must first install the USB drivers from the enclosed USB Driver CD ROM before using Glamr to read the unit. Look on the CD-ROM under Linx SW and perform the instructions in the PDF “Read Me First - Installation Guide” (see Figure 6) Note: This driver is designed for Windows programs only.

Figure 4 SDK Installation CD


NOTE: This is for the installation on machines running the Windows 10 Operating System.

1. Install LINX driver first. This is updated for Windows 10 and is found here:

https://linxtechnologies.com/wp/wp-content/uploads/qs_driver_installer.zip

Do NOT use the FTDI device driver that Windows 10 provides. It does not work with the LINX product even though they are using the FTDI parts. The PID was changed so it is unique.

2. When installing Glamr, there will be an error message saying “Combined.OCX could not be registered.” This is due to missing some DLLs. To get these dependencies, you need to install a Microsoft Redistribution package. This package (language dependent for our foreign customers) can be found at:

https://www.microsoft.com/en-us/download/details.aspx?id=29

Figure 5 shows which files will be available to the user via the SDK Installation Disc. Test data and a User Guide for the unit are also included. If multiple units are purchased, the respective User Guides for each different product will be located on the disc, as well.

Figure 5 Files on Installation Disk

https://linxtechnologies.com/wp/wp-content/uploads/qs_driver_installer.zip

https://www.microsoft.com/en-us/download/details.aspx?id=29


4.4.2 Installing the Direct Drivers The drivers are included and should be saved onto the hard drive of a PC or onto a flash drive. Click on the QS_Driver_Installer.msi for the Setup Wizard.

Click Next

Figure 6 Driver Setup Wizard


Read License, click I Agree, then Next

Figure 7 License Agreement Prompt

Click Next upon arrival at the installation folder prompt

Figure 8 Installation Folder Prompt


Click on Next at the driver package information prompt

Figure 9 Driver Package Information Prompt

NOTE: Plug the connector cable into the USB port before you turn the device power on to avoid Windows loading as a mouse driver.

Allow driver installation to complete

Figure 10 Driver Installation Status

● Windows 8


4.5 Glamr Software Installation Now install the Glamr application off of the CD-ROM. Open the Glamr file (see Figure 11) in the enclosed CD-ROM and install the application to the desired location on the hard drive.

Figure 11 Glamr Location on SDK CD-ROM

Once you installed the Glamr application then you need to create a shortcut on your desktop to the application. Right click on the Glamr Software icon on your hard drive file. Select create shortcut. Drag this shortcut file and drop on your desktop, as shown in Figure 12.

Figure 12 Glamr Software Shortcut Icon


Open the Glamr software and a window will appear as in Figure 13.

Figure 13 Glamr Screen before Selecting Correct COM Port Settings

The bottom of the Gladiator IMU Display may read “IMU serial port (LINX SDM-USB, 115200, 8E2) Error opening.” “LT=1” may also appear if the interface is not LINX. Only one copy of Glamr can be open at a time therefore make sure there is not another copy open on the task bar. If there are multiple copies of Glamr open, a message will appear at the bottom of the IMU Display window.


Reconnect the USB plug to the SDK. The “LINX” port should have a checkmark next to it. The bottom of the window should now read “IMU serial port (LINX SDM-USB, 115200, 8E2) success,” as shown in Figure 14.

Figure 14 Confirmed Correct LINX Port with Message "Success"

Turn on the power switch on the unit power supply and you should see data appear in the window as shown in Figure 15 (colored boxes). You should be able to move the IMU with your hand and see changes in rate and acceleration for each axis located within the IMU on-screen. To see rapid change, the record function will capture real time data without the filter effect on the screen.


4.6 Select Applicable Baud Rate

Baud Rate →

Data Rate ↓

115200 921600 1.5 M 3.0 M Bits/second

100 Yes Yes Yes Yes 19800

200 Yes Yes Yes Yes 39600

500 * Yes Yes Yes 99000

1000 Yes Yes Yes 198000

2500 Yes Yes Yes 495000

5000 Yes Yes 990000

6000 Yes Yes 1188000

Note that the 500 Hz Data Mode is a special case. Please refer to Section 4.9.1 for more details.

Figure 15 Baud Rate Selection for 1000 Hz Data Rate


Figure 16 IMU Data in Full Mode at 1000 Hz Data Rate

The message shown in the lower left of Glamr as: “IMU serial port (LINX SDM-USB, 115200, 8E1, LT=1) success” indicates that the Glamr program is reading the port (Fig. 14). The message “Msg out-of-sequence: exp 0, act 96” indicates that the program saw a skip in the message count. This case will happen at start-up and can be ignored. The message “Accel re-scale set to 0.5” indicates that the program detected a 10g range Accel and rescaled the LSB to take into account a 0.5mg LSB scaling to display and record the units in g’s.


4.7 Select Applicable Stop Bits When using the LMRK60, the number of stop bits is one. This must be reflected in Glamr by making sure the Stop Bits selection is “1.”

Figure 17 Stop Bit Selection for COM Port


4.8 Self-Test in Glamr Glamr includes a self-test function. The user can initiate the self-test by the momentary switch (Fig. 18), contained within the Switch box that is included in the LandMark™ 60 IMU SDK. Press the switch button to activate self-test of the sensors. The Glamr display will now show SELF-TEST is activated while also showing the data outputs. You should see a delta change in the X, Y, and Z sensor outputs when you initiate self-test per the data sheet (Fig. 19).

Figure 18 Power and Self-Test Momentary Switch

Figure 19 Self-Test Display When Activated


4.9 Setting the Mode and Data Rate The SDK software also has a data rate adjustment and data set selection. This feature is selected under Mode as shown. This allows a reduced data set in Spec mode.

4.9.1 Set IMU Mode 500 Hz Data Rate

Figure 20 Mode Selection / Data Rate

NOTE: To reset to another mode once in 500 Hz data rate mode, the unit requires a special procedure if at 115,200 baud rate. Reverting the unit back to any other mode requires a mode click to the desired rate. This will command the unit to wait for a power recycle as per the screen instructions. To set the unit to the new mode upon powering up, turn on power and the new data rate will be shown under the green bars in the upper right corner “xxx msgs per sec.”


All LMRK IMUs can be put into a 500 Hz data rate mode. This is shown in the Figure 21.

Figure 21 IMU Mode at 500 Hz Data Rate


4.10 Unit Display Options The SDK software also can set the dimensional units of the display. This is selected under Units. Figure 22 shows the Rate unit selection.

Figure 22 Gyro Units of Measure Selection Options


Figure 23 shows the Accel unit selection.

Figure 23 Accelerometer Units of Measure Selection Options


4.11 Data Record Feature The SDK software also has a data record feature that captures data outputting from the IMU and puts it into .csv format. This enables the user to easily convert these data files to Excel or database format. The user should click the Start Recording button (Fig. 24) to initiate data record function. When they wish to stop recording, simply click the Stop Recording button.

Figure 24 Data Record Capability


Select “Start Record” and designate the file name and location before the recording begins. To begin Data Record function, click on Open as per Figure 25. After the designated file is established, click the desired length of time to record then click OK (Fig. 26).

Figure 25 Start Record File Path

NOTE: Be sure to look at the Glamr message log to ensure file path is correct and file has successfully been opened for writing.

Click on Open to start recording.


Figure 26 Saving Data Record Time

4.12 Bandwidth Filtering Capability Bandwidth vs. Noise One thing to be aware is that our standard LandMark™ 60 IMU is optimized for high bandwidth, so the gyro bandwidth is set at 250 Hz. True bandwidth with the -3 dB point is approximately 100 Hz when the 200 Hz sample system is included. These are the settings for the standard unit when shipped and the noise may not be optimized for an end-user’s specific application. The high bandwidth is ideal for dynamic applications where the high bandwidth would be required to close control loops in flight control in a UAV, for example. However, in UAV navigation, a lower bandwidth would be possible and there would be an improvement in noise. Laboratory uses, automotive monitoring, or stabilization applications would likely prefer improved noise and could tolerate reduced bandwidth.

Click OK to start recording


Effective with LandMark™ 60 IMU SDK, Gladiator Technologies offers the end-user the capability to set bandwidth filtering in permanent memory that enables the end-user to set lower bandwidth levels than 100 Hz and benefit from the reduced noise of the sensors in the LandMark™ 60 IMU. To utilize this capability, select Load from the drop down menu (Fig. 27).

Figure 27 Select Desired Bandwidth Filter from Drop-Down Menu

Now select the desired true bandwidth of the gyros with the software filter. The user can select from Maximum (standard units are shipped with this setting) or from the other bandwidth options all the way down to 1 Hz. Once this is set and the user takes and confirms data with this new setting the LandMark™ 60 IMU bandwidth filter setting will remain at the setting until the user changes it in the same manner as detailed in this section.

Select desired bandwidth


To help with troubleshooting, users can change what is displayed in the message section of Glamr. This is accessed through the View tab as shown in Figure 28.

Figure 28 Message Options for Troubleshooting

Message section


4.13 CANBUS DBC File The DBC file that describes the CANbus interface can be auto-generated by Glamr based on the current settings using the CANBUS menu item while the unit is connected and active with the device (Fig. 29).

Figure 29 CANBUS DBC File Generation

5 PATENT AND TRADEMARK INFORMATION The LandMark™ 60 IMU is a newly developed unit containing significant intellectual property and it is expected to be protected by United States of America (USA) and other foreign patents pending. LandMark™ is an official and registered Trademark that identifies Gladiator Technologies brand name for our digital inertial and integrated GPS systems products.


6 APPLICABLE EXPORT CONTROLS The LandMark™ 60 IMU has been self-classified by Gladiator Technologies with pending Commodity Classification by the U.S. Department of Commerce under the Export Administration Regulations (EAR), as ECCN7A994 and as such may be exported without a license using symbol NLR (No License Required) to destinations other than those identified in country group E of supplement 1 to Part 740 (commonly referred to as the T-5 countries) of the Export Administration Regulations. Items otherwise eligible for export under NLR may require a license if the exporter knows or is informed that the items will be used in prohibited chemical, biological, or nuclear weapons or missile activities as defined in Part 774 of the EAR. Copies of official U.S. Department of Commerce Commodity Classifications are available upon request.

7 USER LICENSE Gladiator Technologies grants purchasers and/or consignees of Gladiator’s LandMark™ 60 IMU a no cost, royalty free license for use of the following software code for use with the LandMark™ 60 IMU. Companies or persons not meeting the criteria as a purchaser or consignee are strictly prohibited from use of this code. Users in this category wanting to use the code may contact the factory for other user licensing options.

8 STANDARD LIMITED WARRANTY Gladiator Technologies offers a standard one (1) year limited warranty with the factory’s option to either repair or replace any units found to be defective during the warranty period. Opening the case, mishandling, or damaging the unit will void the warranty. Please see Gladiator Technologies’ Terms & Conditions of sale regarding specific warranty information.

9 QUALITY MANAGEMENT SYSTEM Gladiator Technologies’ Quality Management System (QMS) is certified to AS9100 Rev. C and ISO9001:2008. UL-DQS is the company’s registrar and our certification number is 10012334ASH09. Please visit our website at www.gladiatortechnologies.com to view our current certificates.

http://www.bis.doc.gov/PoliciesAndRegulations/index.htm

http://www.access.gpo.gov/bis/ear/pdf/740spir.pdf



10 THEORY OF OPERATION The LandMark™ 60 IMU is a digital 6 Degree of Freedom MEMS (Micro Electro-Mechanical System) IMU that outputs x-, y-, and z-axis angular rates, x-, y-, and z-axis linear acceleration data, as well as temperature. Utilizing Gladiator's proprietary thermal modeling process, this unit is fully temperature compensated, with temperature-corrected bias and scale factor, plus corrected misalignment and g-sensitivity. The unit features:

The RS422/RS485 digital interface provides serial data outputs enabling the user to monitor the outputs during use. Internal sampling is done at 10 kHz. Oversampling is done on the IMU output rate (4X) when set at 2.5 kHz and then averaged to improve the noise of the MEMS sensors. The nominal output rate in the LandMark™ 60 IMU is 1 kHz ± 5%. An RS422/RS485 to USB converter is available in Gladiator's LandMark™ 60 IMU Software Development Kit (SDK) to enable a quick IMU to PC integration and ease of use.

Three MEMS gyro signals with active filtering and 4X oversampled when set at 2.5 kHz with a 16-bit A/D converter. The gyros are available in standard ranges of ± 250°/sec or ± 490°/sec.

Three MEMS accelerometer signals with analog buffering and 4X oversampled when set at 2.5 kHz with a 16-bit A/D converter. The accelerometers are available in standard ranges of ± 6 g’s or ± 10 g’s. Higher g ranges are available upon request. Please contact the factory for further information.

Six internal temperature sensors outputs are 4X over sampled when set at 2.5 kHz with a 16-bit converter. These temperature measurements are co-located with each x-, y-, and z-axis gyro and each x-, y-, and z-axis accelerometer to enable accurate temperature compensation of the gyro and accelerometer outputs.

The calibration process measures temperature at a minimum of five set points from -40°C to +85°C and a nine-point correction table is generated that identifies temperature based offsets for each of the gyro and accelerometer data sets. Depending upon the variable, up to a 4th order thermal model is used to create a correction model.

Though a precision orthogonal mounting block is used in testing the LandMark™ 60 IMU, misalignment error correction is also essential in enabling high performance navigation from a MEMS inertial sensor assembly. The calibration process also corrects and compensates for internal misalignment errors for all sensors in all three axes.

In addition "g-sensitivity" errors associated with the gyros are also modeled and calibrated to correct these performance errors associated with acceleration inputs in all three gyro axes.

All of the calibration data is then loaded into an internal memory EEPROM enabling a look-up table for thermal modeling correction of the outputs during use.


The LandMark™ 60 IMU data sheet is available to our customers via download on our website. For more information please see Gladiator Technologies’ website at www.gladiatortechnologies.com. Copies of the User’s Guides are available upon request at [email protected]. Additionally, the LandMark™ 60 IMU SDK software design enables updates to the IMU interface. As these software enhancements and upgrades become available, Gladiator Technologies will make these available to our IMU customers.

Figure 30 LandMark™ 60 IMU with Mating Connector vs. 2 Euro Coin & US Quarter




11 LandMark™ 60 IMU PRODUCT DESCRIPTION The LandMark™ 60 IMU is our premium performance model featuring both our lowest noise MEMS gyros and accelerometers that also offer outstanding bias in-run and bias over temperature. This high performance MEMS Inertial Measurement Unit (IMU) provides internally temperature-compensated RS422/RS485 output of delta velocity and delta theta. Designed for commercial stabilization and aircraft applications, the LandMark™ 60 IMU is ideal for commercial applications requiring high inertial performance approaching “small RLG or open loop FOG-Class,” yet available at much lower cost. Other key advantages include low power consumption, small size, light weight, and no inherent wear out modes for long life. The signature features of the LandMark™ 60 IMU are the exceptionally low noise and bias performance.

NON-ITAR MEMS IMU

Upgrade for LandMark™ 10/20/40 IMUs

Ultra-Low Gyro Noise 0.0016/sec/Hz

Low Accel Noise 0.05 mg/Hz

Wide Sensor Bandwidth 250 Hz

Gyro Bias In-Run 3°/hour 1σ

Bias Over Temperature ≤ 45°/hour 1σ

Compensated Misalignment ≤ 0.5 mrad

G-Sensitivity < 0.001°/sec/g 1σ

Full Temperature Calibration (Bias and SF)

Vibration 8grms

Shock Resistant 600g

Light Weight ≤ 115 grams

Low Power < 500 mW typical

RS422/428 Data Rate up to 3 kHz (selectable)

CAN bus 2.0B 1 MHz The LandMark™ 60 IMU’s ultra-low noise and low bias MEMS gyros and accelerometers enable precision measurement including excellent in-run bias and bias over temperature. The IMU’s performance is optimized with fully temperature compensated bias and scale factor, as well as compensated misalignment and g-sensitivity. The unit is environmentally sealed in a rugged enclosure and MIL-SPEC connector in order to withstand environmental vibration and shock typically associated with commercial aircraft requirements. The LandMark™ 60 IMU is well suited for demanding commercial applications including: rail track telemetry, navigation, flight control, precision imaging, platform and antenna stabilization, flight testing, and laboratory use. Other standard custom ranges are available.

Figure 31 LandMark™ 60 IMU vs. 2 Euro Coin


11.1 Outline Drawing and 3D Solid Models Please go to the applicable product of interest on our website at www.gladiatortechnologies.com and a user can download the 3D Solid Model, 2D outline drawing, and other product information.

11.1.1 3D Solid Model Figure 32 shows the LandMark™ 60 IMU in a 3D environment.

Figure 32 LandMark™ 60 IMU 3D Model



11.1.2 Outline Drawing

Figure 33 LandMark™ 60 Outline Drawing


11.2 Outline Exploded View & Axis Orientation

Figure 34 LandMark™ 60 IMU Exploded Outline Drawing (metric in [mm])

IMU Axis Orientation


11.3 Center of Gravity Some applications need to know where the navigation (NAV) point of the accelerometers is located. The navigation (NAV) point at which all three accelerometers sensing axes pass through is located along the centerline of the package at a distance from the base plate of 0.45 inches (11.43 mm). From this point there are three size effect distances from this NAV point as follows:

X Accel offset = +0.616 inches (along the x-axis direction) (15.6mm)

Y Accel offset = +0.718 inches (along the y-axis direction) (18.3 mm)

Z Accel offset = +0.167 inches (along the z-axis direction down from the NAV point) (4.23 mm) Note that the Z Accel NAV point can also be expressed as 0.222 inches (5.64mm) up from the base plate. Some applications need to know the CG or center of gravity of the package which is just the mass center. The CG is also along the center line of the package at the midpoint along the z-axis. This is 0.70 inches or 17.7 mm above the base plate.


11.4 IMU Block Diagram

Figure 35 LandMark™ 60 IMU Block Diagram


11.5 LandMark™ 60 IMU Part Naming Convention & Part Numbers

LMRK60 IMU-490-10-100 LMRK 60 IMU 490 10 100

Product Make “LMRK = LandMark™”

Product Model “60”

Product Type “Inertial

Measurement Unit”

Gyro Rate Range

“490°/sec”

Accelerometer linear range

“10g’s”

Specific Unit Configuration

“100”

Figure 36 Gladiator Technologies Part Naming Convention

LandMark™ 60 IMU

LMRK60IMU-250-06-100 or -10

LMRK60IMU-490-06-100 or -10

Figure 37 LandMark™ 60 IMU Part Number Configurations


11.6 LandMark™ 60 IMU Pin Assignments The LandMark™ 60 IMU has a 15 pin MIL-SPEC connector interface which provides the electrical interface to the host application. The signal pin-out is as follows:

Figure 38 LandMark™ 60 IMU Pin Assignments and Outputs

NOTE: If the input pins have long wires with no termination, they can pick up noise in a high EMI environment and upset the proper operation of the IMU. Pin 6 is particularly vulnerable to noise pickup and can cause data drops. For an IMU, Pin 4 is not used and should be grounded. Pin 9 is Self-Test and is OK if connected to a logic level signal source, otherwise connect to Pin 8.

Pin No. Assignment

1 RS-485 A (+) (Twisted Pair)

2 RS-485 B (-) (Twisted Pair)

3 Power Ground

4 Analog/Digital Input (0 V to 5 V)

5 +7 V to +36 V Input Power

6 External Sync Input (up to 3 kHz)

7 +5 V Regulated Output

8 Signal Ground

9 Self Test

10 CAN High

11 CAN Low

12 CAN Gnd

13 N C

14 N C

15 Case

Outputs Serial Sequence

1 Roll Gyro (X)

2 Pitch Gyro (Y)

3 Yaw Gyro (Z)

4 X Accelerometer

5 Y Accelerometer

6 Z Accelerometer

7 Temperature ± 0.5°C typical

Note: Any unused inputs (Pins 4, 6, 9) must be connected

to signal ground (Pin 8).


11.7 LandMark™ 60 IMU Performance Specification See applicable current revision data sheet available on our website at www.gladiatortechnologies.com.

NOTE: Other standard gyro ranges may be available and standard accelerometer ranges of 16g, 30g, 50g, and 70g. Be aware that any selection of these higher ranges will likely result in export categorization of the product as ECCN7A003 and require a U.S. Department of Commerce Export License for some foreign destinations and/or end-use applications. Please see applicable datasheet for other product models and serial number effectivity.

12 LandMark™ 60 IMU MESSAGE PROTOCOL (V72)

12.1 Serial Communication Settings

Parameter Value Bits/second: 115200, 921600, 1.5 Mbit, 3.0 Mbit

Data bits: 8

Parity: E

Stop bits: 1 Note: Glamr Setting

Figure 39 Serial Communication Settings

12.2 IMU Message Packet Format At power-up, the IMU enters operational mode using the last commanded mode setting.

Description Number of bytes

Value LSB weight

Start of message 1 0x2A N/A

Message counter 1 Mod 256 counter N/A

Gyro – X axis 2 Signed 16-bit integer 0.01 deg/sec Note 6

Gyro – Y axis 2 Signed 16-bit integer 0.01 deg/sec Note 6

Gyro – Z axis 2 Signed 16-bit integer 0.01 deg/sec Note 6

Accel – X axis 2 Signed 16-bit integer See Accel LSB Note 7

Accel – Y axis 2 Signed 16-bit integer See Accel LSB Note 7

Accel – Z axis 2 Signed 16-bit integer See Accel LSB Note 7

Temperature 2 Signed 16-bit integer 0.01 deg C

Test/Status indicator 1 Normal=0x00 (note 4) N/A

Checksum 1 Two’s complement sum N/A

Total size 18

Figure 40 IMU Message Packet Format



12.2.1 Important Messaging Protocol Notes

12.2.1.1 Note 1 - Checksum

The checksum is computed by taking the two’s complement of the sum of the first 17 bytes of the message. Thus, performing a byte-wide sum of all 18 bytes in the message always equals zero.

12.2.1.2 Note 2 – Little-Endian Format

All 16-bit data are transferred in little-endian format. Thus, the LSB is received first.

12.2.1.3 Note 3 – Transport Time per Message Packet

Total transport time per message packet:

(18 bytes *11 bits/byte)/115.2 kbits/sec = 1.72 ms

(18 bytes *11 bits/byte)/921.6 kbits/sec = 0.215 ms

(18 bytes *11 bits/byte)/1.5 Mbits/sec = 0.132 ms

(18 bytes *11 bits/byte)/3.0 Mbits/sec = 0.066 ms

12.2.1.4 Note 4 – IMU Status Byte Decoding

Individual bit representation in the test/status byte can be seen in Figure 41.

12.2.1.4.1 Message Counter set to 2 – 246, Bit 6 = 0

Bit Name Value

0 Cal/Test mode indicator 1=Test mode, 0=Cal or Norm

1 Sync 1=external sync, 0=internal sync

2 Interface error 1=internal interface fail

message count even = I2C device

message count odd = SPI device

3 Flash checksum error 1=Flash coefficient checksum fail

4 Software error 1=internal software fail

5 Software timing error 1=software missed real-time

6 Status byte select 0 (bits 2-5, bit 7 are status)

7 Self-test 1=self-test active

Figure 41 Status Byte Decode when Bit 6 is 0


12.2.1.4.2 Message Counter set to 2 – 246, Bit 6 = 1

Bit Name Value 0 Gyro Range indicator 0= Norm, 1=Wide

1 Accel range bit 0 000b=default, 001b=3g,

010b=2g,011b=6g, 100b=10g, 101b=16g,

110=32g, 111b=65g

2 Accel range bit 1

3 Accel range bit 2

4 Gyro range LSB Norm- 11b=250°/s

Wide- 01b=490°/s 5 Gyro range MSB

6 Status byte select 1 (bits 2-5, bit 7 are settings)

7 Digital board rev 9 1=rev9 (or greater), 0=rev 8

Figure 42 Status Byte Decode when Bit 6 set to 1 (every other message)

12.2.1.4.3 Message Counter set to 0 or 1

Message Count

Bit 7 Name Value (Bits 6:0)

0 0 IMU SW major revision number 0 to 127

0 1 IMU SW product code 0 to 127

1 0 IMU SW minor revision number 0 to 127

1 1 IMU SW release level number 0 to 127

Figure 43 IMU Status Byte Decode when Message Count set to 0 or 1

12.2.1.4.4 Message Counter set to 247 (AHRS)

Message Count

Name Value

247 Bandpass filter number 0 = unknown

1-99 = valid

100 = maximum

> 100 = TBD

Figure 44 Status Byte Decode when Message Count set to 247


12.2.1.4.5 Message Counter Set to 248 – 251

Message Count

Name Value

248 Board Number Byte 0 0 to 255




Figure 45 Status Byte Decode when Message Count set to 248 through 251

12.2.1.4.6 Board Number Encoding

The board number is a 32-bit value that encodes five characters in a 6-bit format.

Bit 31 Bit 30:25 Bit 24:18 Bit 17:12 Bit 11:6 Bit 5:0

0 Char 5 Char 4 Char 3 Char 2 Char 1

Figure 46 Board Number Encoding (32-bit to 6-bit)

The encoding of a character is as follows:

Value 0 – “space” character

Value 1 through 10 – “0” character through “9” character

Value 11 - 36 – “A” character through “Z” character

Value 37 – 63 – Undefined


12.2.1.4.7 Serial Number when Message Counter set to 252 – 255.

IMU status byte decode when message counter set to 252 through 255.

Message Count Name 8-Bit Value 32-bit Value

252 Serial Number Byte 0 0 to 255 Bits 24-31




Figure 47 Status Byte Decode when Message Count set to 252 through 255

After appending the four transmitted 8 bit words to a 32 bit binary, convert this to decimal.

The 32-bit value stores 6 character values in a modulo 37 (% 37) format as follows:

Character Value 6 = (32-bit value) % 37

Character Value 5 = (32-bit value / 37) % 37

This is the next character to the left of the one you just decoded.

Repeat this again and again till you finish all 6 characters.

Character Value 4 = (32- bit value / 37 / 37) % 37

Character Value 3 = (32-bit value / 37 / 37 / 37) % 37

Character Value 2 = (32-bit value / 37 / 37 / 37 / 37 ) % 37

Character Value 1 = (32-bit value / 37 / 37 / 37 / 37 / 37) % 37

The encoding of a character value allows for an alphanumeric serial number is as follows:

Value 0 – “space” character

Value 1 through 10 – “0” character through “9” character

Value 11 through 36 – “A” character through “Z” character

Serial Number Encoding Example:

Frame Status 252 0x0C 253 0xBC 254 0xE1 255 0x2F

32 Bit Number = 0x0CBCE12F = 213705007 (decimal) char 6 = 213705007 % 37 = 0 char 5 = (213705007 / 37) % 37 = 5775811 % 37 = 0 char 4 = (5775811 / 37) % 37 = 156103 % 37 = 0 char 3 = (156103 / 37) % 37 = 4219 % 37 = 1 char 2 = (4219 / 37) % 37 = 114 % 37 = 3 char 1 = (114 / 37) % 37 = 3 % 37 = 3

Then, using the encoding, we get SN = “220 ”


12.2.1.5 Note 5 – Accel LSB and Accel Over-Range

The Accel LSB scaling depends on the g-range of the Accels in the selected IMU device. Please note that some accelerometers may have inherent over-range versus the range reflected on the datasheet. An example is the 16g part number. This accelerometer is designed to have over-range up to 20+ g’s. As the LSB is set to an equal to or less than Accel Range, the user would want to use the next higher up Accel range LSB in order to use the inherent over-range of the applicable Accel. In this example they would instead use the 30g Accel Range and the associated LSB of 0.0010g.

12.2.1.6 Note 6 – Gyro LSB Scale Factor

The Gyro LSB scale factor depends on the rate-range of the Gyros:

Status Bits [5:4:0] Gyro Range Value LSB Scale Factor 000 Default (no value listed) 0.01°/s

011 490 0.015°/s

110 250 0.00763°/s

111 N/A N/A

Figure 48 Gyro LSB Scale Factor

12.2.1.7 Note 7 – Accelerometer LSB Scale Factor

The Accel LSB scale factor depends on the g-range of the Accels.

Status Bits [3:2:1] Accel Range Value LSB Scale Factor 001 ≤ 3g 0.0001 g

010 ≤ 2g 0.0001 g

011 ≤ 6g 0.0005 g

100 ≤ 10g 0.0005 g

000 ≤ 15g 0.0005 g

101 ≤ 16g 0.0005 g

011 ≤ 32g 0.0010 g

111 ≤ 65g 0.0020 g

Figure 49 Accel LSB Scale Factor


12.2.1.8 Important User Interface Comments

The IMU messaging protocol is quite important and can be somewhat confusing for the user. Please note that the proper sequence of the output data is:

Start Byte

Message Count

Gyro X

Gyro Y

Gyro Z

Accel X

Accel Y

Accel Z

IMU Temp

Status Byte (based on Message Count)

Checksum Also, the IMU’s LSB should be 0.01 deg/sec for gyros and 0.0005 for 10g Accels and 0.0001 for 2g Accels as well as 0.01 degrees for temperature. So you divide the data by 100 for the gyros and temperature and divide by 2,000 for 10g or 10,000 for 2g accelerometers to get the corrected data without using the Software Development Kit. The Glamr software interface does the 10g or 2g accelerometer correction for the user internally. If you are not using the Software Development Kit, then you will need to do this divide function to get corrected data.


12.3 Sample Data Format Figure 50 provides a sample IMU data output in Excel. The real output includes both the header information and data (see rows with MSGCOUNT) that contain actual output data. Also included are the multiplier information, averages, and units of measure for additional clarity. The IMU Software Development Kit also includes the actual Excel file as in Figure 50, so that the user can quickly identify the formulas to use in their system integration directly from the sample data file.

Figure 50 Screenshot of LandMark™ 60 IMU Sample Data

Please note that when the customer uses the Glamr interface it automatically rescales the accelerometers, so there is no divide by function required for the accelerometers. This is displayed in Figure 50, as well as the sample Excel file included in the LandMark™ 60 IMU Software Development Kit (SDK). However, if the user is not using Glamr and inputting directly into their system, then they should use the LSB’s noted above (LSB 0.01 deg/sec for gyros and 0.0005 for 10g accels and 0.0001 for 2g accels, as well as 0.01 degrees for temperature).


12.3.1 CAN Output Messages The following table summarizes the output data stream messages from the device for each of its various modes. The transmit sequence follows from top to bottom in the table, with the start of message byte transmitted first and the checksum transmitted last in all cases. At power-up, the device reads the operation mode (i.e. Full, Spec, etc.) from its Flash storage and begins to transmit data in that mode. Figure 51 is an example of CAN output.

Figure 51 IMU CAN Output

Refer to section entitled “CANBUS DBC File” for how to generate the associated CAN database file associated with the unit.

12.4 Sync Input (5 kHz) The optional input to the IMU is a sync square wave to Pin 6. This allows the data stream to be synchronized to an external clock. For example, if the user wants to supply and sync an external GPS to the IMU the GPS typically generates a 2.5 kHz square ware and this is sent to the IMU when the GPS signal is valid. However, any external 2.5 kHz clock of logic level can be used to synchronize the data.

12.4.1 Specification

Clock 2.5 kHz ± 5% square wave (40 - 60 duty cycle not critical)

Data sample starts on the rising edge only

3.3 V logic is suggested (-0.3 V < “0” < 0.8 V and 2.0 V < “1” < 5.3 V)

Input has diode protection for levels below -0.7 V or above 5.5 V to 10.5 V to protect the CPU, but excessive levels may cause performance problems.


12.4.2 Status Bit The IMU will operate on an internal 2.5 kHz clock until an external clock is detected. Then the IMU will automatically switch over and set Status Bit 1 true. It should be noted that as the internal and external clocks are asynchronous, the first transition will take a few clock periods to align. The status bit will be set true for that period even if there is only one sample. However, the next 200 Hz data package will all be samples on the external clock. Refer to the timing diagram to see the relationship between external clock and data transmission (Figure 52). The time between the 5th (last sample) and the start of the 200 Hz data transmission is 1.5 ± 0.05 msec. If the start of the external sync is delayed to between 2.5 msec and 3.5 msec from the start of the 200 Hz data package transmission, then all 5 of the next 1 kHz samples will be on the external clock. If the delay is close to 3.5 msec, then the internal to external clock shift will have minimum impact on the data as this is the first sample clock. The IMU will revert to the internal clock if the external clock is removed and data will continue to be sent. In most cases the timing of the external sync application is not critical and the data can be used as is.

12.4.3 Timing Diagram

Figure 52 2.5 kHz Timing Diagram


12.4.4 Bit Values for External Sync Input

Bit Name Value 0 Cal/Test mode indicator 1=Test mode, 0=Cal mode (Factory)

1 Sync transition 1=external/internal sync change

2 interface error 1=fail

3 Flash checksum error 1=Flash coefficient checksum fail

4 Software error 1=internal software fail

5 Output processing error 1=software missed real-time

6 AD processing error 1=software missed real-time

7 Self-test 1=self-test active

Figure 53 Bit Values for External Sync Input

12.5 Bandwidth vs. Noise Note that our standard LandMark™ 60 IMU is optimized for high bandwidth, so the gyros are set at 250 Hz. True bandwidth includes the data sampling effects and has the -3 dB point, which is approximately half of the sample frequency. These are the settings for the standard unit when shipped and the noise may not be optimized for an end-user’s specific application. The high bandwidth is ideal for dynamic applications where the high bandwidth would be required to close control loops in flight control in a UAV, for example. However, in UAV navigation a lower bandwidth would be possible and the unit would output an improvement in peak-to-peak noise. Laboratory uses, automotive monitoring or stabilization applications would likely prefer improved (lower) noise and could tolerate reduced bandwidth. The LandMark™ 60 IMU Software Development Kit offers the end-user the capability to set bandwidth filtering in permanent memory. This enables the end-user to set lower bandwidth levels than the sensor bandwidth in order to benefit from the reduced peak-to peak noise of the sensors in the IMU.

Figure 54 Bandwidth Frequency and Output Data Rate


Figure 55 Gyro Bandwidth vs. Peak-to-Peak Noise 100 Hz

Figure 56 Gyro Bandwidth vs. Peak-to-Peak Noise 1 kHz


13 SAMPLE TEST DATA & TEST METHODS

13.1 Gladiator ATP Explanation

13.1.1 Rate Spin Test Data is captured at 100 Hz data rate. The unit is mounted on an orthogonal test fixture and spun at about half of the full scale rate range. The data comes across as a raw number with an LSB of 0.01 deg/sec. This means that all the data has to be divided by 100 to get into degrees per second units. The spin rate in the data below was 144°/sec. Each column is the data taken for the axis name at the top of the column during the test at the left. The final values printed in green fall within the “passing” values for the unit (note that all passed).

Figure 57 Rate Spin Test


13.1.2 Accelerometer Tumble Test Data is captured at 100 Hz data rate. The unit is mounted on an orthogonal test fixture and placed in ± 1g and ± 0g in this test. During this test the gyro and accelerometer biases are measured as well as the gyro g-sensitivity and the accelerometer misalignments are measured. The data comes across as a raw number with an LSB of 1 milli-g.

Figure 58 Accelerometer Tumble Test Data


13.2 Angle Random Walk The unit is mounted on an orthogonal fixture and is turned on with no input. Data is captured at 200 Hz data rate. The white noise due to angular rate is measured. ARW is typically expressed in our datasheets in degrees per second per square root hertz (°/sec/√Hz), which is standard for most MEMS gyros. However, our performances are now commensurate with higher performing small open loop FOGs and small RLG’s, so we also denote ARW in degrees per square root hour [°/√h].

Figure 59 Angle Random Walk (ARW)


13.3 Velocity Random Walk The unit is mounted on an orthogonal test fixture and is turned on with no input. Data is captured at 200 Hz data rate. We measure the velocity errors that build up with time due to white noise in acceleration,. VRW is typically expressed in our datasheets in milli-g per square root hertz (mg/√Hz), which is standard for most MEMS accelerometers. However, our performances are now approaching higher performing quartz based servo accelerometers, so we also denote VRW in meters per second per square root hour [(m/s)/√h]. This from a 6g range accelerometer:

Figure 60 Velocity Random walk


13.4 Bias In-Run The unit is placed on an orthogonal test fixture. Data is captured at 100 Hz data rate. Then the bias of the accelerometers and gyros are measured at 1 Hz average. After a five minute warm-up period, the data is taken for five minutes at ambient temperature. The test conditions should be similar to what a user should likely have during initial setup approximately within five minutes after turn-on.

Figure 61 X Gyro Bias In-Run


Figure 62 Y Gyro Bias In-Run


Figure 63 Z Gyro Bias In-Run


Figure 64 X Accelerometer Bias In-Run


Figure 65 Y Accelerometer Bias In-Run


Figure 66 Z Accelerometer In-Run Bias


13.5 Bias and Scale Factor over Temperature Data is captured at 100 Hz data rate. The temperature calibration process measures temperature at a minimum of five set points from -40°C to +85°C at a slew rate of approximately 1°/minute. A nine point correction table is generated that identifies temperature based offsets for each of the gyro and accelerometer data sets. Depending upon the variable, up to a 4th order thermal model is used to create a correction model. The black line is the model fit to the blue diamond data points (Fig. 67).

13.5.1 Gyro Bias over Temperature

Figure 67 X Gyro Bias over Temperature


Figure 68 Y Gyro Bias over Temperature


Figure 69 Z Gyro Bias over Temperature


13.5.2 Gyro Scale Factor over Temperature

Figure 70 X Gyro Scale Factor over Temperature


Figure 71 Y Gyro Scale Factor over Temperature


Figure 72 Z Gyro Scale Factor over Temperature


13.5.3 Accelerometer Bias over Temperature

Figure 73 X Accelerometer Bias over Temperature


Figure 74 Y Accelerometer Bias over Temperature


Figure 75 Z Accelerometer Bias over Temperature


13.5.4 Accelerometer Scale Factor over Temperature

Figure 76 X Scale Factor over Temperature


Figure 77 Y Scale Factor over Temperature


Figure 78 Z Accelerometer Scale Factor over Temperature


13.6 Bias Turn-On (from a Cold Start) The LandMark™ 60 IMU is NOT specified for this condition. This data is supplied for customer reference only. Data is captured at 100 Hz data rate for 25 minutes (one second average data can be seen in Figures 79-84). Test conditions assume a unit has been powered off for a minimum of at least five minutes and then data is taken at ambient temperature from initial power-on to determine sample turn-on transient performance. It should be noted that most of the turn-on transient occurs during the initial two minutes after power-on and after that it performs near the specified Bias In-Run performance level.

Figure 79 X Gyro Bias Turn-On


Figure 80 Y Gyro Bias Turn-On


Figure 81 Z Gyro Bias Turn-On


Figure 82 X Accelerometer Bias Turn-On


Figure 83 Y Accelerometer Bias Turn-On


Figure 84 Z Accelerometer Bias Turn-On


13.7 Random Vibration

13.7.1 Random Vibration Data is captured at 200 Hz data rate on a factory shaker. The unit is subject to random frequencies with total energy contained in the vibration profile of 5.74grms. The delta shift for each gyro and accelerometer is measured before and after the run. Also measured during vibe is the Vibration Rectification Coefficients (VRC) of the unit.

Figure 85 Random Vibration Test Data


13.7.2 Sine Vibration Test Data is captured at 200 Hz data rate on a factory shaker. The unit is subject to a sine sweep of various frequencies from 30 Hz to 3000 Hz and delta shifts are calculated before and after the run. Also measured during vibe is the Vibration Rectification Coefficients (VRC) of the unit from 200 Hz to 1 kHz.

13.7.3 Gyro Sine Vibration Response

Figure 86 X Gyro Sine Vibration Response

Figure 87 Y Gyro Sine Vibration Response

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

11

72

53

44

95

17

36

89

78

62

11

03

45

12

06

91

37

93

15

51

71

72

41

18

96

52

06

89

22

41

32

41

37

25

86

12

75

85

29

30

93

10

33

GYRX (°/s)

GYRX (°/s)

-2.5

-2

-1.5

-1

-0.5

0

0.5

1

1.5

2

11

74

13

48

15

22

16

96

18

70

11

04

41

12

18

11

39

21

15

66

11

74

01

19

14

12

08

81

22

62

12

43

61

26

10

12

78

41

29

58

13

13

21

GYRY (°/s)

GYRY (°/s)

Shaker Resonance

Shaker Shut Off

Shaker Resonance

Shaker Shut Off


Figure 88 Z Gyro Sine Vibration Response

13.7.4 Accelerometer Sine Vibration Response

Figure 89 X Accelerometer Sine Vibration Response

-1.5

-1

-0.5

0

0.5

1

1.5

2

2.51

17

93

35

85

53

77

71

69

89

61

10

75

3

12

54

5

14

33

7

16

12

9

17

92

1

19

71

3

21

50

5

23

29

7

25

08

9

26

88

1

28

67

3

30

46

5

32

25

7

GYRZ (°/s)

GYRZ (°/s)

-6000

-4000

-2000

0

2000

4000

6000

8000

1

17

25

34

49

51

73

68

97

86

21

10

34

5

12

06

9

13

79

3

15

51

7

17

24

11

89

65

20

68

9

22

41

3

24

13

7

25

86

1

27

58

5

29

30

9

31

03

3

ACCX (mg)

ACCX (mg)

Shaker Shut Off

Shaker Resonance

Shaker Shut Off


Figure 90 Y Accelerometer Sine Vibration Response

Figure 91 Z Accelerometer Sine Vibration Response

-6000

-4000

-2000

0

2000

4000

6000

80001

18

38

36

75

55

12

73

49

91

86

11

02

3

12

86

0

14

69

7

16

53

4

18

37

1

20

20

8

22

04

5

23

88

2

25

71

9

27

55

6

29

39

3

31

23

0

ACCY (mg)

ACCY (mg)

-8000

-6000

-4000

-2000

0

2000

4000

6000

1

18

92

37

83

56

74

75

65

94

56

11

34

7

13

23

8

15

12

9

17

02

0

18

91

1

20

80

2

22

69

3

24

58

4

26

47

5

28

36

6

30

25

7

32

14

8

ACCZ (mg)

ACCZ (mg)


14 MOUNTING Mounting for the LandMark™ 60 IMU accommodates both metric and U.S. mounting screws. Mount the unit to a flat surface with 4ea. 8-32 or M4 screws. Be sure that the surface the unit is being mounted to is as clean and as level as possible in order to eliminate potential alignment errors. Adequate mounting to a surface should fall within a flatness of +/- 0.001” or +/- 0.025 mm. Failing to mount the unit in this fashion can result in unaccounted stress in the sensors and therefore may affect data output. Gladiator Technologies strongly encourages the user to mount the unit correctly in the described manner to ensure proper functioning.

15 OPERATION & TROUBLESHOOTING

15.1 Technical Assistance Please contact the factory or your local Gladiator Technologies sales representative's office for technical assistance.

15.2 Authorized Distributors and Technical Sales Representatives If you need additional assistance please contact your local distributor and/or the factory for further technical support.

http://www.gladiatortechnologies.com/Intl/Contact.html

Technical Support - USA

Gladiator Technologies

Attn: Technical Support

8020 Bracken Place SE

Snoqualmie, WA 98065 USA

Tel: 425-396-0829 x222

Fax: 425-396-1129

Email: [email protected]

Web: www.gladiatortechnologies.com

http://www.gladiatortechnologies.com/Intl/Contact.html




15.3 Technical Support Website Our Technical support webpage has user training videos, the latest software downloads, as well as Remote Desktop Assistance.

For direct assistance, Gladiator Technologies offers Remote Assistance (Fig. 95 and Web

Conferencing (Fig. 96). If you need assistance and would like to set up a remote desktop

session, please visit join.me.com.

For assistance navigating the Gladiator Technologies website, see Figures 92-94.

Figure 92 Website – Select Product Category


Figure 93 LandMark™ 60 IMU Product Main Webpage

The Technical support webpage has user training videos; the latest software downloads as well as Remote Desktop Assistance.

Figure 94 LandMark™ 60 IMU Product Documentation Downloads


Figure 95 Remote Desktop Support Web Page


Figure 96 Web Conferencing Web Page


16 GLOSSARY OF TERMS Gladiator Technologies has attempted to define terms as closely as possible to the IEEE Gyro and Accelerometer Panel Standards for Inertial Sensor Terminology. Please note that in some instances our definition of a term may vary and in those instances Gladiator Technologies' definition supersedes the IEEE definition. For a complete listing of IEEE's standard for inertial sensor terminology please go to www.ieee.org.

16.1 Abbreviations and Acronyms 6DOF: six degrees-of-freedom IMU: Inertial Measurement Unit CVG: Coriolis Vibratory Gyro ESD: Electro Static Discharge IEEE: The Institute of Electrical and Electronics Engineers IMU: Inertial Measurement Unit MEMS: Micro Electro-Mechanical Systems NLR: No License Required

16.2 Definitions of Terms Acceleration-insensitive drift rate (gyro): The component of environmentally sensitive drift rate not correlated with acceleration. NOTE—Acceleration-insensitive drift rate includes the effects of temperature, magnetic, and other external influences. Acceleration-sensitive drift rate (gyro): The components of systematic drift rate correlated with the first power of a linear acceleration component, typically expressed in (°/h)/g. Accelerometer: An inertial sensor that measures linear or angular acceleration. Except where specifically stated, the term accelerometer refers to linear accelerometer. Allan variance: A characterization of the noise and other processes in a time series of data as a function of averaging time. It is one half the mean value of the square of the difference of adjacent time averages from a time series as a function of averaging time.

http://www.ieee.org/


Angular acceleration sensitivity: (accelerometer): The change of output (divided by the scale factor) of a linear accelerometer that is produced per unit of angular acceleration input about a specified axis, excluding the response that is due to linear acceleration. (gyro): The ratio of drift rate due to angular acceleration about a gyro axis to the angular acceleration causing it. NOTE—In single-degree-of-freedom gyros, it is nominally equal to the effective moment of inertia of the gimbal assembly divided by the angular momentum. Bias: (accelerometer): The average over a specified time of accelerometer output measured at specified operating conditions that have no correlation with input acceleration or rotation. Bias is expressed in [m/s2, g]. (gyro): The average over a specified time of gyro output measured at specified operating conditions that have no correlation with input rotation or acceleration. Bias is typically expressed in degrees per hour (°/h). NOTE—Control of operating conditions may address sensitivities such as temperature, magnetic fields, and mechanical and electrical interfaces, as necessary. Case (gyro, accelerometer): The housing or package that encloses the sensor, provides the mounting surface, and defines the reference axes. Composite error (gyro, accelerometer): The maximum deviation of the output data from a specified output function. Composite error is due to the composite effects of hysteresis, resolution, nonlinearity, non-repeatability, and other uncertainties in the output data. It is generally expressed as a percentage of half the output span. Coriolis acceleration: The acceleration of a particle in a coordinate frame rotating in inertial space, arising from its velocity with respect to that frame. Coriolis vibratory gyro (CVG): A gyro based on the coupling of a structural, driven, vibrating mode into at least one other structural mode (pickoff) via Coriolis acceleration. NOTE—CVGs may be designed to operate in open-loop, force-rebalance (i.e., closed-loop), and/or whole-angle modes. Cross acceleration (accelerometer): The acceleration applied in a plane normal to an accelerometer input reference axis. Cross-axis sensitivity (accelerometer): The proportionality constant that relates a variation of accelerometer output to cross acceleration. This sensitivity varies with the direction of cross acceleration and is primarily due to misalignment. Cross-coupling errors (gyro): The errors in the gyro output resulting from gyro sensitivity to inputs about axes normal to an input reference axis.


Degree-of-freedom (DOF) (gyro): An allowable mode of angular motion of the spin axis with respect to the case. The number of degrees-of-freedom is the number of orthogonal axes about which the spin axis is free to rotate. Drift rate (gyro): The component of gyro output that is functionally independent of input rotation. It is expressed as an angular rate Environmentally sensitive drift rate (gyro): The component of systematic drift rate that includes acceleration-sensitive, acceleration-squared-sensitive, and acceleration-insensitive drift rates. Full-scale input (gyro, accelerometer): The maximum magnitude of the two input limits. G: The magnitude of the local plumb bob gravity that is used as a reference value of acceleration. NOTE 1—g is a convenient reference used in inertial sensor calibration and testing. NOTE 2—In some applications, the standard value of g = 9.806 65 m/s2 may be specified. Gyro (gyroscope): An inertial sensor that measures angular rotation with respect to inertial space about its input axis(es). NOTE 1—The sensing of such motion could utilize the angular momentum of a spinning rotor, the Coriolis effect on a vibrating mass, or the Sagnac effect on counter-propagating light beams in a ring laser or an optical fiber coil. G sensitivity (gyro): the change in rate bias due to g input from any direction. hysteresis error (gyro, accelerometer): The maximum separation due to hysteresis between upscale-going and down-scale-going indications of the measured variable (during a full-range traverse, unless otherwise specified) after transients have decayed. It is generally expressed as an equivalent input. Inertial sensor: A position, attitude, or motion sensor whose references are completely internal, except possibly for initialization. Input angle (gyro): The angular displacement of the case about an input axis. Input axis (IA): (accelerometer): The axis(es) along or about which a linear or angular acceleration input causes a maximum output. (gyro): The axis(es) about which a rotation of the case causes a maximum output. Input-axis misalignment (gyro, accelerometer): The angle between an input axis and its associated input reference axis when the device is at a null condition. Input limits (gyro, accelerometer): The extreme values of the input, generally plus or minus, within which performance is of the specified accuracy.


Input range (gyro, accelerometer): The region between the input limits within which a quantity is measured, expressed by stating the lower- and upper-range value. For example, a linear displacement input range of ± 1.7g to ± 12g. Input rate (gyro): The angular displacement per unit time of the case about an input axis. For example, an angular displacement input range of ± 150°/sec to ± 300°/sec. Input reference axis (IRA) (gyro, accelerometer): The direction of an axis (nominally parallel to an input axis) as defined by the case mounting surfaces, or external case markings, or both. Linear accelerometer: An inertial sensor that measures the component of translational acceleration minus the component of gravitational acceleration along its input axis(es). Linearity error (gyro, accelerometer): The deviation of the output from a least-squares linear fit of the input-output data. It is generally expressed as a percentage of full scale, or percent of output, or both. Mechanical freedom (accelerometer): The maximum linear or angular displacement of the accelerometer’s proof mass, relative to its case. Natural frequency (gyro, accelerometer): The frequency at which the output lags the input by 90°. It generally applies only to inertial sensors with approximate second-order response. Non-gravitational acceleration (accelerometer): The component of the acceleration of a body that is caused by externally applied forces (excluding gravity) divided by the mass. Nonlinearity (gyro, accelerometer): The systematic deviation from the straight line that defines the nominal input-output relationship. Open-loop mode (Coriolis vibratory gyro): A mode in which the vibration amplitude of the pickoff is proportional to the rotation rate about the input axis(es). Operating life (gyro, accelerometer): The accumulated time of operation throughout which a gyro or accelerometer exhibits specified performance when maintained and calibrated in accordance with a specified schedule. Operating temperature (gyro, accelerometer): The temperature at one or more gyro or accelerometer elements when the device is in the specified operating environment. Output range (gyro, accelerometer): The product of input range and scale factor. Output span (gyro, accelerometer): The algebraic difference between the upper and lower values of the output range.


Pickoff (mechanical gyro, accelerometer): A device that produces an output signal as a function of the relative linear or angular displacement between two elements. Plumb bob gravity: The force per unit mass acting on a mass at rest at a point on the earth, not including any reaction force of the suspension. The plumb bob gravity includes the gravitational attraction of the earth, the effect of the centripetal acceleration due to the earth rotation, and tidal effects. The direction of the plumb bob gravity acceleration defines the local vertical down direction, and its magnitude defines a reference value of acceleration (g). Power spectral density (PSD): A characterization of the noise and other processes in a time series of data as a function of frequency. It is the mean squared amplitude per unit frequency of the time series. It is usually expressed in (°/h)2/Hz for gyroscope rate data or in (m/s2)2/Hz or g2/Hz for accelerometer acceleration data. Principal axis of compliance (gyro, accelerometer): An axis along which an applied force results in a displacement along that axis only. Proof mass (accelerometer): The effective mass whose inertia transforms an acceleration along, or about, an input axis into a force or torque. The effective mass takes into consideration rotation and contributing parts of the suspension. Quantization (gyro, accelerometer): The analog-to-digital conversion of a gyro or accelerometer output signal that gives an output that changes in discrete steps, as the input varies continuously. Quantization noise (gyro, accelerometer): The random variation in the digitized output signal due to sampling and quantizing a continuous signal with a finite word length conversion. The resulting incremental error sequence is a uniformly distributed random variable over the interval 1/2 least significant bit (LSB). Random drift rate (gyro): The random time-varying component of drift rate. Random walk: A zero-mean Gaussian stochastic process with stationary independent increments and with standard deviation that grows as the square root of time. Angle random walk (gyro): The angular error buildup with time that is due to white noise in angular rate. This error is typically expressed in degrees per square root of hour [°/√h]. Velocity random walk (accelerometer): The velocity error build-up with time that is due to white noise in acceleration. This error is typically expressed in meters per second per square root of hour [(m/s)/√h]. Rate gyro: A gyro whose output is proportional to its angular velocity with respect to inertial space. Ratio metric output: An output method where the representation of the measured output quantity (e.g., voltage, current, pulse rate, pulse width) varies in proportion to a reference quantity.


Rectification error (accelerometer): A steady-state error in the output while vibratory disturbances are acting on an accelerometer. Repeatability (gyro, accelerometer): The closeness of agreement among repeated measurements of the same variable under the same operating conditions when changes in conditions or non-operating periods occur between measurements. Resolution (gyro, accelerometer): The largest value of the minimum change in input, for inputs greater than the noise level, that produces a change in output equal to some specified percentage (at least 50%) of the change in output expected using the nominal scale factor. Scale factor (gyro, accelerometer): The ratio of a change in output to a change in the input intended to be measured. Scale factor is generally evaluated as the slope of the straight line that can be fitted by the method of least squares to input-output data. Second-order nonlinearity coefficient (accelerometer): The proportionality constant that relates a variation of the output to the square of the input, applied parallel to the input reference axis. Sensitivity (gyro, accelerometer): The ratio of a change in output to a change in an undesirable or secondary input. For example: a scale factor temperature sensitivity of a gyro or accelerometer is the ratio of change in scale factor to a change in temperature. Stability (gyro, accelerometer): A measure of the ability of a specific mechanism or performance coefficient to remain invariant when continuously exposed to a fixed operating condition. Storage life (gyro, accelerometer): The non-operating time interval under specified conditions, after which a device will still exhibit a specified operating life and performance. Strapdown (gyro, accelerometer): Direct-mounting of inertial sensors (without gimbals) to a vehicle to sense the linear and angular motion of the vehicle. Third-order nonlinearity coefficient (accelerometer): The proportionality constant that relates a variation of the output to the cube of the input, applied parallel to the input reference axis. Threshold (gyro, accelerometer): The largest absolute value of the minimum input that produces an output equal to at least 50% of the output expected using the nominal scale factor. Turn-on time (gyro, accelerometer): The time from the initial application of power until a sensor produces a specified useful output, though not necessarily at the accuracy of full specification performance. Warm-up time (gyro, accelerometer): The time from the initial application of power for a sensor to reach specified performance under specified operating conditions.


Zero offset (restricted to rate gyros): The gyro output when the input rate is zero, generally expressed as an equivalent input rate. It excludes outputs due to hysteresis and acceleration.

LandMark 60 IMU (Inertial Measurement Unit) Technical User ... · LandMark™ 60 IMU (Inertial...

Documents

Transcript of LandMark 60 IMU (Inertial Measurement Unit) Technical User ... · LandMark™ 60 IMU (Inertial...