2011:Electrical Main

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Electrical Subteam Members

  • Students

Alex Rozanov

Vaughn Thompson

Matthieu Dora

Henry Wagner

  • Mentors

Dave Burlone

Dean Smith

Christian Stoeckl

Dave Schoepe

Tentative Attendance Calendar


Sunday Monday Tuesday Wednesday Thursday Friday Saturday


  • Dave B
  • Christian S.
  • Alex R.


  • Dave B.
  • Dean S.
  • Vaughn T.
  • Alex R. (testing)


  • Dean S.
  • Dave S
  • Matthieu D


  • Dave B.
  • Dave S
  • Matthieu D


  • Dave B - 1pm - 4pm 
  • Dean S. - 10am - 6pm
  • Dave S - 11am - 4pm
  • Matthieu D - 1pm-9pm


  • Dave B - 11am-3pm
  • Dave S - 11am-4pm



Sunday Monday Tuesday Wednesday Thursday Friday Saturday


  • Dave B
  • Dean S.
  • Matthieu D


  • Dean S
  • Matthieu D


  • Dave B
  • Dean S
  • Matthieu D
  • Dave S.


Makeup Day for

2/2/11 Snow day

  • Dave S


  • Dave B - 1-5
  • Dean S - 10am - 6pm
  • Dave S


  • Dave B
  • Dave S



  • Dave B
  • Dean S


  • Dave S  7-9


  • Dave B
  • Dean S


  • Dave B
  • Dean S - 10am - 6pm
  • Dave S


  • Dave S


  • Dean Smith


  • Dave B
  • Dave S


  • Dean Smith
  • Dave S


  • Dave B
  • Dean Smith
  • Dave S


  • Dean Smith
  • Dave S


  • Dean Smith
  • Dave S
20  RALLY !!! 21 22  SHIP DATE !!! 23 24 25 26

Master Task List

High Priority

  • Determine mounting spots for the battery (Completed 1/29)
  • Create fixture for mounting the battery (Completed 1/29)
  • Design (in a modeling program) a new control board layout to fit all electronics
  • Test brightness of LED tape when mounted on a pipe. (Completed 1/22)

Medium Priority

  • Get Arachnaphobia in OK working order.
  • Put cables on new batteries (See Subtasks)Complete
  • Test batteries with power meter and record electronic results on wiki (See Subtasks)
  • Design signal lights ("want-it"/"got-it")   Design Complete (see Subtasks)
  • Choose encoder for Arm Axle 2011_Encoders Complete 1/23
  • Design photoelectric sensor (similar to Banner offerings) Completed 1/23
  • Work with programming on line sensors calibrating, adjusting etc.  (See Subtasks!)
  • Construct/prototype photoelectric sensor (Completed 1/27)
    • Decided to use Banner Industrial sensors.
    • Would only swing between 2.7V and 5V (need to use analog input)
    • Not as compact
    • Will want to experiment with this in preseason as these are 20x more cost effective
  • Re-Crimp Ethernet cables for use at Rally and competitions
  • Need to measure +12V power bus droop when all motors running - if too low (<10.8V), may need to power line sensors from pneumatics module of cRio so they don't drop out during autonomous.

Low Priority

  • Prep gyro - needs set of pins soldered to the board (completed 1/29)
  • Crimp PWM ends to flying leads of Drivetrain wheel encoders (completed 1/29)
  • Get correct faston connectors for smaller motors so we don't have to solder wires to them. (we have .187" size but the .150" size is nonstandard and will have to be soldered)

Sub Task List

Control Board In Inventor

The current drive train design is almost complete in Inventor this means that we can start drawing in the control board.

  • Must have at least three different designs to be flexible with mechanical group
  • Must evaluate positives and negatives of any structural elements used to mount electronics (Completed 1/26)
    • Do a force test of the new corrugated plastic alongside a similar piece of polycarbonate.
    • Measure the deflection and record the findings on the wiki to indicate if this is an upgrade or downgrade and by what percentage
    • Place weight calculations on the wiki - Stress Calculations
  • Think about cable routing and cable management. Do we have the wire guages and colors we need??? (Completed 2/6/11)
  • Think about how hard/easy it is to work on at competition, and visibility of LED's for troubleshooting (cRio, Jaguars, spikes).
  • Should mount speed controller in an accessible spot (like on 2010/2009) robots
  • Work on centering battery  (Completed 2/6/11)

Check all Batteries:

  • The batteries should have the tape removed and crimps checked and redone if needed.(Completed 1/18)
  • Terminate tester with the appropriate leads (Completed 1/23)
  • Test Batteries with tester, plot and save results electronically on the wiki (should be ongoing)

Experiment with Line Sensors:

  • Pull out a power supply and scope, find out how the sensors work, and test range and sensitivity.
  • Mock up on Thunderfoot for initial testing (Completed 1/15)
  • Test under different lighting conditions but on same surface
  • Test orientation of sensor (in 90 degree increments) (Completed 1/22) - Makes little to no difference

Measure Mach 1511 Polycarb

This is the thickness of the polycarb to use on the control board and order a sheet.  Will use corrugated plastic, not polycarb sheet.

CAN Bus Minutia

  • Make two Serial to CAN converters- include CAN termination resistor
  • Make two CAN terminators 
  • Make four CAN cables
  • Need to remember that the first CAN node (from the cRIO) needs a terminating resistor

Safety Light: Wire up the Orange Safety Light on Mock board - Complete 1/15

Communication Signals 

  • Plan and design human player communication lights.
  • Want-It Light(s)
  • Got-It Light
  • Need to test visibility (Completed 1/22 - we will use 2 wraps of LED lighting)
  • Pick materials
  • Choose mounting spot
  • Construct

Motors: Inventory and test motors. - Complete 1/13

Links to Other Subteams' Important Stuff

2011:Robot IO Map

Robot Electromechanical Design Features 

Bill of Materials


  1. Drivetrain motors (2)
  2. Arm elevation motor
  3. Arm unfold/extend This is unnecessary, unfolding is a mechanical function ONLY
  4. Gripper rollers (2 independant motors)
  5. Minibot deployment release
  6. Signal lights


  1. Gyro
  2. Drivetrain motors speed and direction (2)
  3. Arm angle
  4. Line tracking sensors (3)
  5. Arm limit switches (opto)
  6. Gripper "got-it" sensor (opto)

ARM PLACEMENT ACCURACY Need to determine the required resolution (accuracy) of the arm angular sensor.

This is a very, very rough determintaion, based on some assumptions (because I didn't have the robot & arm dimensions). -Dave S

  • Placement accuracy required:
  1. ubertube central hole is 12"
  2. scoring peg foot is 2.75"
  3. If perfectly centered, this leaves approx 4.5" gap between tube and scoring peg.
  4. Let's cut this in half to have some safety margin, and say we need to place the tube within 2" during autonomous mode.
  • Sensor resolution required:
  1. Fully extended arm reaches to 9.5' (114")
  2. ASSUME that arm is pivoted at a point 48" above ground in the center of the robot, then the arm's length is about 68".
  3. the circumference of the arc the arm traces is 427"
  4. so 2"/427" times 360 degrees for a full circle gives about 1.7 degrees as corresponding to 2" in arm rotation out at the gripper.
  5. To allow for some margin of error, let's say we need to sense the arm angle at least within 1.0 degree.

So need to choose a sensor with 1 degree of angular resolution or better.

  • IF use an analog sensor, cRio 9201 module is 12-bit ADC for a full scale input range of -10V to +10V. We would likely use less than its full range so we would not get its maximum  resolution - the reference voltage for the ADC is internal and not user selectable.

         edit:  Generally, the SW team usually throws away the bottom two bits of ADC readings as it's likely noise.

  • Followup: the requirement for picking up a tube from the ground may be "tougher". Estimate that we need 1" placement accuracy, so need to improve arm sensor resolution to 0.5 degrees.

Robot Sensor Requirements

Drivetrain Sensors

  • US Digital E4P Rotary Encoder (2) - Directly coupled to gearboxes
  • Rockwell line following sensor (3+) - Mounted as close to center as possible
  • Three in a line at the front of the bot, 1 inch off the floor (to the lens) center one fixed and the others adjustable from adjacent to 1 inch away.
  • Gyro (KOP)

Arm Sensors

  • Some Calculations (Arm Placement Accuracy) show that we need 1-2 degree tolerance 0.5 degree minimum accuracy on the sensor.
  • If using a potentiometer we should fine 1% tolerance pots
  • If using encoders must use both A & B phase for maximum accuracy
  • Optical switches at extremes - Mounted as a flags (2) on the 12" sprocket
  • Home Position Sensor
    • Will be an optical sensor (OPTEK OPB815L)
    • In the parked position the sensor will output 1
    • Once the arm leaves the parked position the sensor will read 0
    • When it leaves the parked position, this indicates "sensor home".  This is the SW absolute point.
  • 2 encoders for redundancy
  • We decided to go with the E4P sensor instead of the E7P
  • The E4P would be able to get up to .5 of a degree of arm rotation accuracy which is above our goal
  • Worked with mechanical to determine that we will mount the encoders at the intermediate (or main) driveshaft of the arm.
  • The E7P would be able to get .25 degrees of rotation, but is twice as expensive


  • Needs at least 1 "Got It" Sensor (maybe 2?) decided for just 1 got-it sensor (2/5/11)
  • Would be nice to make this sensor active low
  • We should impose the mechanical team to design a mechanical stop
  • Will drive the "Got It" Light

Motor Outputs

General Assumption:  CAN Based Motor Controls


  • 2 x Jaguar and  2 x CIM
  • motor will be protected with 40A breaker


  • 1 x Jaguar and  Banebots M7-RS775-18 (electrical tabs are 0.187"W x 0.025"THK)
  • motor will be protected with a 20A breaker


  • 2 x Jaguar and  2 x Banebots M5-RS540-12  (electrical tabs are 0.150"W x 0.020"THK)
  • motor will be protected with a 20A breaker

Visual Feedback


  • Used to relay to the human player what type of tube needs to be fed to the robot
  • Needs to be viewable from all angles
  • No breakables for this


  • Used to tell the robot drive team that the robot is in "good" possession of a tube
  • Needs to be viewable from all angles
  • Needs to be viewable from far distances
  • No breakables for this

Electrical Main Subteam's Engineering Notebook

Week 1

Week 2

Week 3

Week 4

Week 5

Week 6

Engineering Notebook Templates Available at: Engineering_Notebook_Template

Please Label All Notebook Pages 2011:Electrical Main MM.DD to avoid confusion.

Component Specifications

Jaguar Speed Controllers

Jaguar Firmware Notes

Victor 884 Speed Controllers

File:2011 Motor Curves.pdf

2009 KOP Motors Spreadsheet (Chief Delphi)



Micro Switches

Electrical Inventory

File:BDC24 RDK UM.pdf

File:MX5 CircuitBreaker.pdf

File:VB3 CircuitBreaker.pdf

File:Natl Instruments 9201 AnalogModule.pdf

Line Sensor Notes

US Digital Encoders

Slotted Switch Optical Sensor


Custom Board Schematic

Custom Control Board Schematic.png

IO Pin Maps for Old Robots