1. 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

2. 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?


3. Robot Data Schematic

4. 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


5. 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


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 (digital in/out)
16 Relay Outputs (drives Spikes)
I2C headers (Standard and NXT-compatible)
12V supply,
 Provides +5V output
 Reverse polarity protected

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. 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


13. 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


14. Analog Breakout

15. 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


16. Pneumatics Breakout

17. 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


18. Powering the DAP-1522
DC-DC converter must be used
 Converts 12 VDC to 5 VDC


19. Ethernet Camera – Axis M1011 or
206
Streaming video for drivetime control has been
challenging
 Connects to RJ45 on cRIO
 Can be used to track colors
and shapes


20. 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


21. 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


22. Talon Motor Controller
Simple controller, but very robust
 PWM interface only
 Brake and coast jumper
 Fan optional


23. 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


24. Spike “H-Bridge”
Relay operation
 On-Off-Reverse
 Connects to “relay” output of digital
sidecar, not PWM
 Use for on-off motor control,
compressor


25. 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


26. 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 nondrive functions


27. 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


28. 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


29. 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


30. 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

31. 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)

32. Helpful Hints

33. Working the Wago
• 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
Yes !
NO !
End View

34. 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”


35. 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


36. 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


37. 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.

38. 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

39. 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

40. Wrapping Up

Go to the FIRST website
◦ FRC – Resources – Technical Resources

41. 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