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*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. | *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. | ||
<br> | ''edit: Generally, the SW team usually throws away the bottom two bits of ADC readings as it's likely noise | ||
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= Robot Sensor Requirements<br> = | = Robot Sensor Requirements<br> = |
Revision as of 13:52, 21 January 2011
Electrical Subteam Members
- Students
Alex Rozanov
Vaughn Thompson
Matthieu Dora
Henry Wagner
- Mentors
Dave Burlone
Dean Smith
Christian Stoeckl
Dave Schoepe
Master Task List
High Priority
- Determine mounting spots for the battery
- Create fixture for mounting the battery
- Design (in a modeling program) a new control board layout to fit all electronics
- Test brightness of LED tape when mounted on a pipe.
Medium Priority
- Put cables on new batteries
- Test batteries with power meter and record electronic results on wiki
- Design signal lights ("want-it"/"got-it")
- Choose encoder for Arm Axel
- Design photoelectric sensor (similar to Banner offerings)
Low Priority
- Prep gyro - needs set of pins soldered to the board
- Crimp PWM ends to flying leads of DT wheel encoders
Sub Task List
- Control Board in Inventor: The current drive train design is almost complete in Inventor this means that one of the kids can start drawing in the control board.
- Check all Batteries: The batteries should have the tape removed and crimps checked and redone if needed.(Completed 1/18) Larry is talking about buying a power meter that will graph the battery.
- Experiment with Line Sensors: Pull out a power supply and scope, find out how the sensors work, and test range and sensitivity.
- Measure Mach 1511 Polycarb: This is the thickness of the polycarb to use on the control board and order a sheet.
- CAN Bus: Make two Serial to CAN converters, two CAN terminators, four CAN cables
- Safety Light: Wire up the Orange Safety Light - Complete 1/15
- Communication Signals: Plan and design human player communication lights, this is being discussed on the forums, may or may not be used.
- Motors: Inventory and test motors. - Complete 1/13
Links to Other Subteams' Important Stuff
Robot Electromechanical Design Features
OUTPUTS
- Drivetrain motors
- Arm elevation motor
Arm unfold/extendThis is deprecated, unfolding is a mechanical ONLY- Gripper rollers
- Minibot deployment release
INPUTS
- Gyro
- Drivetrain motors speed and direction
- Arm angle
- Line tracking sensors
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:
- ubertube central hole is 12"
- scoring peg foot is 2.75"
- If perfectly centered, this leaves approx 4.5" gap between tube and scoring peg.
- 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:
- Fully extended arm reaches to 9.5' (114")
- 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".
- the circumference of the arc the arm traces is 427"
- 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.
- 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
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
- Gyro (KOP)
Arm Sensors
- Some Calculations (Arm Placement Accuracy) show that we need 1-2 degree tolerance 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
- Limit switches at extremes/home-position
- Potentially have 2 arm sensors for redundancy
Manipulator
- Needs at least 1 "Got It" Sensor (maybe 2?)
- 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
Drivetrain
- 2 x Jaguar - CIM
Arm
- 1 x Jaguar - CIM?
Manipulator
- 2 x Jaguar - Continuous Rotation Servo
Visual Feed Back
Want-It-Indicator
- 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
Got-It-Indicator
- 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
2009 KOP Motors Spreadsheet (Chief Delphi)
File:Natl Instruments 9201 AnalogModule.pdf
Bill of Materials (Electrical)
Archives