This document provides an overview of the electronics components used for a robotics competition, including: 1) The control system is centered around a National Instruments cRIO controller with I/O modules. Rookie teams will receive a smaller 4-slot cRIO compared to veterans' 8-slot models. 2) Other key components are a digital sidecar for PWM/DIO outputs, a power distribution module, analog and pneumatics breakouts, and motor controllers. 3) The operator interface consists of a netbook running control software connected via wireless to the cRIO, along with joysticks and a programmable I/O expansion device to monitor switches/buttons.

1. Overview of Electronics
1425 Wilsonville Robotics
Tim Bennington-Davis
tbenningtondavis@ixiacom.com
(503) 449-9507

2. At a glance
New NI controller (cRIO)
◦ Smaller, 4 slots, less weight, less cost
Microsoft Xbox Kinect adapter

3. Robot Schematic

4. Elements of the System
National Instruments cRIO
Digital Sidecar
Power Distribution Board
Analog Bumper
Pneumatics Bumper
Netbook Driver Station
Wireless Interface (802.11)
Camera
Motor controllers and relays

5. cRIO
ModularController, 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

6. cRIO and Modules
Legacy Teams have 8-slot cRIO chassis
Rookie teams will get new 4-slot cRIO

7. 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
◦ 16 Relay Outputs
◦ I2C headers (Standard and NXT-compatible)
◦ 12V supply,
 Provides +5V output

8. Digital Sidecar

9. 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

10. Power Distribution Module

11. Power Distribution Diagram

12. Analog Breakout
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 bumper has power
Power to bumper requires wiring to
power distribution module

13. Analog Bumper

14. 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 bumper has power
Power to bumper requires wiring to
power distribution module, can tolerate
12v or 24v to match solenoids

15. Pneumatics Breakout

16. Wireless Interface – 802.11
Radio on the robot is 802.11 wireless
bridge
Check for how to power it correctly from
your robot
You will assign fixed IP addresses to your
components, using team number
Use as AP during build season, connect to
the wired field at the competition
Field will use 5 GHz band to avoid overlap
and interference

17. Ethernet Camera – Axis M1011
Streaming video for drive-
time control has been
challenging
Connects to RJ45 on cRIO
Can be used to track colors

18. Jaguar Motor Controller
Replaces the venerable Victor
CAN bus interface, 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

19. Operator Interface
Classmate Computer or equivalent
Must run supplied software
IP connected
Communicates constantly with cRIO
USB expansion hub
Joysticks (USB)
Cypress pSOC I/O expansion device

20. 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

21. 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

22. 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

23. 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

24. 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
3-axis accelerometer (supplied)
Gyro (supplied)
Analog Ultrasonic detectors
For measuring close distances

25. Helpful Hints

26. Working the Wago
• Find a Wago tool (Newark Electronics)
• 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

27. 802.11 Radio Link
The AP and bridge have changed over
the years.
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

28. Other ideas worth remembering
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

29. Wrapping Up
Go to the FIRST website, navigate
◦ FRC
◦ Game and Season Info
◦ Competition
◦ Competition Manual and Related Docs
Check out the schematics, rules and
manuals from last year
◦ Wire gauge requirements, terminals, etc.