CV Robotics Team 955
Electrical Team Certification
Jamie Moore 2013
Why do we need a certification?
• Many students are new to electrical work
and need some help getting started
• Provides a standard way of doing things
• Wiring failures are a leading cause of dead
robots and lost matches!
Certification process
1.
2.
3.
4.
Attend training session
Study supplied materials
Take written exam
Interview with electrical mentor and
demonstrate proper wiring technique
5. Receive cool skill badge upon successful
completion!
Certification goals
Be able to
• Identify and describe the main electrical
components used on the robot
• Read and follow an electrical diagram
• Properly wire components for safe, reliable
operation
12V SLA Rechargeable Battery
Features
• 18 Ah capacity
• 150A max rated output
• Rechargeable up to 250 times
• Sealed lead acid chemistry
• Can be used in any position
• 3-5 year life expectancy
The 12V SLA Rechargeable Battery
is the sole source of electrical power
for the robot
Main Circuit Breaker
Features
• 120A protection rating
• Integrated switch
• Insulated terminal caps
The Main Circuit Breaker protects the
entire electrical system and acts as the
master power switch
Power Distribution Board
Features
• 8 40A protected outputs
• 12 30A protected outputs
• 24V 1.5A power supply
• 12V 2A power supply
• 5V 3A power supply
• Reverse battery protection
• Wago terminal blocks
The Power Distribution Board supplies
protected power from the battery to all
the other electrical components
cRIO-FRC II Controller
Features
• Reconfigurable via plug-in
modules
• Built in Ethernet and serial ports
• 400 MHz processor, 128 MB ram
• Spartan 6 LX45 FPGA
• 256 MB disk storage
The cRIO-FRC II is a real time
embedded controller chassis that
runs the robot software and controls
all of the I/O
Analog Breakout Module
Features
• 2 – 20 VDC input
• 5V 0.25A supply for
sensors
• Standard 3 pin interface
• Interfaces with NI 9201
The Analog Breakout Module is used
to wire analog sensors to the cRIO NI
9201 module and to monitor the
battery voltage
Solenoid Breakout Module
Features
• 6 – 30 VDC input
• Interfaces with NI 9472
• Reverse polarity
protection
The Solenoid Breakout Module is used to wire
pneumatic solenoid valves to the cRIO NI 9472
module
Digital Sidecar
Features
• 10 PWM outputs
• 14 general purpose I/O
• 16 relay outputs
• Robot signal light header
• 5V/3A power supply
• Interfaces with NI 9403
• Reverse-battery protection
The Digital Sidecar is a digital I/O breakout
module for the cRIO NI 9403 module
Robot Signal Light
Features
• Bright, wide angle
• Panel mount
The Robot Signal Light is used to indicate the
status of the robot and is a required safety feature
Talon Motor Controller
Features
• PWM input
• 60 amp rating
• Small footprint
• Passive cooling
• Linear response
• Simple calibration
• Smart status indicator
The Talon provides bidirectional
speed control of CIM drive motors
CIM Brushed DC Motor
Features
• 12V DC
• 5310 RPM
• 343 oz-in torque
• 375 Watts
• 133 Amp stall current
Multiple CIM DC motors are used to
power the robot drive system
Spike H-Bridge Relay
Features
• 20 amp rating
• Bidirectional control
• Simple digital interface
• Small footprint
The Spike H-Bridge Relay provides bidirectional
control of small motors such as an air compressor
5V Power Converter
Features
• 5V @ 5A output
• Overload protected
• High efficiency (90%)
• Integrated heat sink
The 5V Power Converter is used to generate the
power needed for the D-Link Wireless Bridge
D-Link Wireless Bridge
Features
• 2.4 and 5 GHz bands
• Ethernet 10/100T base
• Wireless access point
The D-Link Wireless Bridge provides a communication
link between the driver station and the robot
Axis M1013 Network Camera
Features
• 800 x 600 max resolution
• 67 degree field of view
• Adjustable focus
• Video compression
The Axis M1013 Network camera provides a
live compressed video stream from the robot
Electrical Power Diagram
Electrical Signal Diagram
Wiring 101
1. Use the correct wire gauge for the load
2. Determine the routing path prior to measuring
and cutting the wire to length plus some extra
3. Crimp and mount the wire on the component side
first, using a lock washer
4. Route the wire back to the Power Distribution
Board using tie-downs along the way
5. Cut the wire to the final length
6. Crimp a ferrule on the end of the wire and insert it
into the appropriate Wago connector
Selecting the correct wire gauge
• Refer to FRC rules for wire gauge and color
• Only three gauges typically needed
– 6 gauge for up to 100 Amps
• Battery connections
• Main circuit breaker
– 12 gauge for up to 40 Amps
• Motor controller
• Spike relay
– 18 gauge for up to 20 Amps
• Everything else (except PWM cables)
Wire routing examples
Ad hoc
Planned
Example pictures taken from Team 2338 cable management guide
Crimping for success
1.
2.
3.
4.
5.
6.
Use the right tool for the job
Match the connector size to the wire gauge
Strip off the correct length of insulation
Crimp connector with ratcheting crimp tool
Test the crimp for mechanical strength
Test the crimp for electrical resistance
Crimping tools
Ratcheting crimper for insulated connectors
Self adjusting crimper for wire ferrules
Wire strippers
Used for medium/large gauge wire
Used for small gauge wire
Anatomy of a good crimp
Measuring crimp resistance
Use Ohms Law to calculate the
resistance of a crimped connection
1. Apply 5 - 10 amps through the wire
2. Measure the voltage across the crimp
3. Use V / I to calculate the resistance
Ohms Law Formula Wheel