Emanuel Oliveira, Vítor Santos * Centre for Mechanical Technology and Automation
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Transcript of Emanuel Oliveira, Vítor Santos * Centre for Mechanical Technology and Automation
Emanuel Oliveira, Vítor Santos *Centre for Mechanical Technology and AutomationDept. Mechanical Engineering - University of Aveiro
3810-193 AveiroPortugal
Fibre Optics Gyroscope Evaluation and Calibrationwith a Mobile Robot
* E-mail: {eamaral, vsantos}@mec.ua.pt
SIRS2000
Contents:
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope and odometers performance on irregular floor
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University SIRS2000
What is a Laser Gyroscope?
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
A device that measures angular rotation by using internal generated, counter-propagating, optical beams.
Sagnac effect
c
LD2
for Open-loop fibre optic interferometers
SIRS2000
Gyroscope applications
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
Avionics
Naval
Land vehicles
Mobile robots
Underwater
NavigationIndustry
Automotive
industry
Generalindustry
Steering gearCar navigationBreaking system
Tilt sensing
Mobile robots
Platform stabilizationMotion sensing
SIRS2000
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
Mobile robots
SIRS2000
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
Mobile robots
SIRS2000
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
Mobile robots
SIRS2000
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
Mobile robots
SIRS2000
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
Mobile robots
SIRS2000
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
Mobile robots
SIRS2000
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
Mobile robots
SIRS2000
Gyroscope in mobile robotsGyroscope in mobile robots
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
When used in dead-reckoning, it can:
- increase accuracy in short-term information;
- reduce the requirements in absolute position updates.
SIRS2000
Autogyro from KVH IndustriesMain specifications
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
Power supply 12 V
Power consuption 3 W
Output16 bits, RS-232, 9600 bps, 10 values/sec
Rotation rate (max) ±100 º/sec
Drif rate (compensated)
5-10 º/h
Angle random walk (noise)
20 º/hr/Öh
< 0.5% rms (constant temp.) < 1% (full temp.)
Scale factor linearity
SIRS2000
Drift rate definition:1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Output signal when the gyroscopeis not rotating around its sensitive axis.
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University SIRS2000
Drift rate definition:1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Output signal when the gyroscopeis not rotating around its sensitive axis.
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
Random and systematic components
SIRS2000
Drift rate definition:
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Output signal when the gyroscopeis not rotating around its sensitive axis.
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
Random and systematic components
SIRS2000
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
Drift rate definition:
Output signal when the gyroscopeis not rotating around its sensitive axis.
Random and systematic components
SIRS2000
Drift rate compensation
100 samples
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
-0.126 º/s
Subtract to the subsequent gyroscope outputs
SIRS2000
Orientation variation measurement using ultrasonic
sensors1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
max<1º
Measurement accuracy
d1(max)= d2(max)=5mm max<1º
d2
d1
D
D
dd 21arctan
Orientation variation measurement using ultrasonic
sensors1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University SIRS2000
Orientation error without any correction
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University SIRS2000
Correction factor calculation
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
where(t,) - rotation rate at the instant t and temperature
() - correction factor at temperature
If temperature is constant for all integration period†
†In practice the temperature varied less than 0.5 ºC in a 20 sec test.
T
real dtt0
)(),(
T
real dtt0
),()( T
real dtt0
),()(
measured
realT
real
dtt
0 )(
)(
SIRS2000
Correction factor calculation
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
CWCCW
Using least square method...
SIRS2000
Results after calibration
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
CW
CCW
SIRS2000
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
Before After
Improvement of ca. 60% in absolute orientation accuracy
SIRS2000
Gyroscope and odometer performanceon irregular floor
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
Gyroscope
Odometers
Real
Gyroscope and odometer performanceon irregular floor
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University SIRS2000
Gyroscope and odometer performanceon irregular floor
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University SIRS2000
Conclusions
1. Introduction
2. Gyroscope specifications
3. Drift rate compensation
4. Orientation error correction
5. Results
6. Gyroscope/odometers performance
7. Conclusions
Fibre Optics Gyroscope Evaluation and Calibration with a Mobile Robot
Dept. of Mechanical Engineering - Aveiro University
• Temperature correction is very important in orientation errors compensation;
• Gyroscope is an essential sensor for outdoors environment navigation.
– Using linear correction factor it lead to 60% improvement in orientation accuracy
– Non linear correction factor or piecewise linear fitting can improve results for a higher temperature range.
– Gyroscope was immune to bumps and wheel slippage (the most relevant errors in odometry).
SIRS2000