Overview of Control System

2013/2014 Season

Tim Bennington-Davis

Mentor for team 1425 (Error Code Xero – Wilsonville)

Robot Inspector

FTA for 2014 Districts

tbenningtondavis@ixiacom.com

(503) 449-9507

Agenda

What are the parts?

How do they fit together?

How does the system work?

Where can I learn more?

What advice can be passed along?

Robot Data Schematic

Elements of the System

National Instruments cRIO (brains)

Digital Sidecar (make signals available)

Power Distribution Board & Battery

Analog Breakout (analog inputs)

Pneumatics Breakout (drives solenoids)

Netbook Driver Station

Wireless Interface (802.11)

Camera

Motor controllers and relays

cRIO

Modular Controller, Industrial Strength

Comes with multiple interface modules

◦ 2 Analog Input Modules

Plus 2 Analog Breakout

◦ 2 Digital Input/Output Modules

Connect via really big cable to Digital Sidecar

◦ 1 Digital Output Module

Use with Solenoid Breakout

Veteran teams do not get new cRIO’s and

modules

Rookie teams will get new smaller cRIO

cRIO and Modules

Legacy Teams have 8-slot cRIO chassis

Rookie teams will get new 4-slot cRIO

Digital Sidecar

Connects to cRIO9403 with 32-pin cable

Provides

◦ 10 PWM outputs (Victors, Jaguars, RC servos)

Can be configured on a per-output basis to drive 6V

RC servos with jumpers

◦ 14 GPIO with +5V on each (digital in/out)

◦ 16 Relay Outputs (drives Spikes)

◦ I2C headers (Standard and NXT-compatible)

◦ 12V supply,

Provides +5V output

Reverse polarity protected

Digital Sidecar

Power Distribution Module

Custom Design by FIRST

6-15 VDC, reverse polarity protected

Metric shanks, not SAE!

8 outputs for 40A breakers

12 outputs for 30A/20A breakers

24VDC output for CompactRIO

12V output

5V output for camera

LED’s for power supplies and open

breakers

Power Distribution Module

Power Distribution Diagram

Battery

12 VDC, sealed lead-acid

MUST use one of two models

◦ MK ES17-12

◦ Enersys NP18-12

Battery Exchange in Oregon City can get

them

Don’t wait too long to order

Analog Breakout

Supplies +5V/3A for powering sensors

8 Analog Inputs, 3 pin PWM cable config.

Mounts to NI 9201 Analog Module

Configurable to make one input capable

of measuring battery voltage - mandatory

LED to indicate unit has power

Power to unit requires wiring to power

distribution module

Analog Breakout

Pneumatics Breakout

Reverse-battery protection

8 Outputs to directly drive solenoids

Mounts to NI 9472 Digital Module

Means you don’t have to use Spikes to

drive solenoids anymore

◦ Save weight, space and money

LED to indicate unit has power

Power to unit requires wiring to power

distribution module, can tolerate 12v or

24v to match solenoids

Pneumatics Breakout

Wireless Bridge – DAP-1522

802.11n MIMO

Must use DAP-1522, Rev B1

You will assign fixed IP addresses to your

components, using team number

Powering the DAP-1522

DC-DC converter must be used

Converts 12 VDC to 5 VDC

Ethernet Camera – Axis M1011 or

206 Streaming video for drive-

time control has been

challenging

Connects to RJ45 on cRIO

Can be used to track colors

and shapes

Jaguar Motor Controller

Grey (old) and Black – they are different

CAN bus interface, current limit features

Do NOT remove the power screws

They are “swaged” on the end, which is

meant to keep them from coming out

Removing them drops metal shavings

into the guts

Jaguar Motor Controller

Black units have conformal coating to

minimize damage if screws are removed

Have integral PID speed control, provided

you hook up encoders

PWM or CAN interface

Direct connect to wheel encoders

You may get vouchers for controllers so

you can choose

Talon Motor Controller

Simple controller, but very robust

PWM interface only

Brake and coast jumper

Fan optional

Victor Motor Controller

Also simple and robust

Newest model is 888. 884 also usable.

PWM interface only

Brake and coast jumper

No PID closed-loop control

Spike “H-Bridge”

Relay operation

On-Off-Reverse

Connects to “relay” output of digital

sidecar, not PWM

Use for on-off motor control,

compressor

Operator Interface

Classmate Computer or equivalent

Must run correct version of supplied

software – CHECK UPDATES!

IP connected

Communicates constantly with cRIO

USB expansion hub

Joysticks (USB)

Cypress pSOC I/O expansion device

Many teams use their own computers

Operator Interface

Typically a 48” x 8” console

Joysticks or other driving interface

Buttons, switches, dials, lights

Your team designs and builds it

Effective driving operation is enabled by

careful ergonomic design, especially

when it comes to controlling the non-

drive functions

Operator Interface

Cypress board provides 16 configurable

digital pins, 8 analog inputs

Plug into proto board, or build/buy

carrier board

Digital and analog functions map to

software

Typical OI Functions

switch (on/off) – 1 digital input

3 position switch (on/off/on) – 2 digital

inputs

Potentiometer (variable position) – 1

analog input

Push button switch (momentary

contact) – 1 digital input

Indication (LED) – 1 digital output

Link between OI and cRIO

Default software causes cRIO and

classmate computer to update each

other several times a second

All OI data is fed to cRIO automatically

If they don’t talk, your robot disables

itself

Status of communication shown in

classmate GUI

Other Handy Parts

10-turn potentiometers

Not supplied – Norvac, Fry’s, Digi-Key

Wire to analog input

US Digital Quadrature Encoders

Mount in many transmissions

Count transmission rotation, direction

Can interface directly with Jaguars

3-axis accelerometer (supplied)

Gyro (supplied)

Analog Ultrasonic detectors

For measuring close distances

Sources for parts

Digikey and Mouser (web ordering, fast

shipping, good prices)

Fry’s and Oregon Electronics (more expensive,

but stock on shelf. Limited assortment)

US Digital (quadrature encoders)

Sparkfun electronics (sensors, arduinos)

Pololu robotics (sensors, arduinos)

Helpful Hints

Working the Wago

Yes !

NO !

• Find a Wago tool, or make one. Most screwdrivers cause damage

• Take care to insert directly at a fixed angle, pressing straight in

• Do not pry. The goal is to open the spring by pressing in the

screwdriver, not by prying

End View

802.11 Radio Link

Only the DAP-1522 Rev B is acceptable at

events

Learn how to set static IP addresses on

your PC, and how to log into AP and

adapter to configure them manually

Turn off “Wireless Protection”, so that

inadvertent presses of external buttons

don’t change settings unexpectedly

At competitions, must put switch in

“bridge”

Bridge Placement

The DAP-1522 has antennas at either end

Uses both antennas for 802.11n MIMO

Mount it up away from robot frame,

motors, cRIO

Don’t show up with a Rev-A model

Hints Learned the Hard Way

Solder your terminals – prevent failure

Keep large gauge wiring as short as possible

Lay your electronics out so you can

troubleshoot it – 2 layers sometimes works

Make a battery charging record

◦ During tournaments, know which one is charged

Read the inspection rules early – a great “cheat

sheet” for guiding you

Label your wires or use color markings, to

make troubleshooting easier

Robot frame is NOT connected to ground

Hints Learned the Hard Way

Use red wire for +, black wire for –

Never lift a battery by the leads.

Shut off the power before plugging or

unplugging any thing!

Cover electronics when doing metal work

above – metal shavings will ruin your day

Pay attention to wire gauge requirements

All electrical failures are mechanical in nature

…. Make your electrical connections so they

will survive being whacked. - check before

every round.

Hints Learned the Hard Way

Before bagging your robot….. Inspect it

◦ Get an experienced robot inspector to come to your

location and go over it.

◦ Minimize the number of surprises you may

experience at your first event

◦ If pre-inspection is allowed, take advantage of it

At the first competition … get out for a

practice match

◦ This gives you a chance to confirm connecting to the

field

Hints Learned the Hard Way

At the competition

◦ There is no power for your custom laptop at the

driver station of the field.

◦ YOU MAY NOT PLUG YOUR DS LAPTOP IN AT

THE FIELD – so keep your battery charged

Develop and use a checklist to use before each

match

◦ Matches do not get re-run because your robot has a

loose wire, dead battery, or wasn’t properly prepared

Wrapping Up

Go to the FIRST website

◦ FRC – Resources – Technical Resources

Wrapping Up

Read last year’s Robot Rules Manual

Look at the schematics and technical

information from last year – now!

Visit an experienced team for a day

Ask around

◦ Tim Bennington-Davis

tbenningtondavis@ixiacom.com

(503) 449-9507