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Set up encoder motor set on skeleton board for software and firmware to test while mechanical fixes drive train issues
If command send for close loop control does not work, power off and do not send additional commands as that will overheat motor driver in lock-in state. Motor driver and wires will overheat significantly and cause fumes and damage to rest of electronics
Mechanical side will RCA on manufacturing and assembly side
Grease the turning parts or using bearings to make connection smoother. Believe performance will be even better than now with working L2 set up
Need to test all the motor without load and test the motor functionality
Add On Follow Up Test
Started with L3 motor, in earlier testing was not giving enough torque. Took motor and encoder off drive train to test separately. When speed was set to 10, applied force on motor outer shell. Observed motor would stop when force is applied, then when force is taken off the motor would not recover rotation. Wire would heat up when this happens from current draw
2 hypothesis: motor is bad, needs to be replaced
Odrive protection mechanism for different tuning motors
Internal fixture is causing additional friction
Observation: when force is being added on bad motors over current limit is not stopping the motor, causing overheating
Note: Forces were added directly on outer shell of the motor. Performance would be better when it is mounted with the wheel
Summary
All 5 motors disassembled 3 motors were labelled as bad, other 2 performed strong torque resistance that we expected. More tests needed.
L3, R1, L1
Testing Results May 23rd
Test 1:
Retested the 5 motors, confirmed that 2 were behaving as expected exerting necessary torque while the other three would lock-in and draw too much current heating up the wires when torque was applied
Note: Some of the wires came out of the encoders, need to be addressed and fixed
Test 2:
Using the 2 good motors, mounted them onto the drive train, respectively R2 and R3. R2 ran as expected after being mounted, calibration was successful and motor ran for 1 minute at velocity 10 and 20.
R3 would go through calibration sequence but when ran at velocity it would lock-in. Hypothesis is mechanical issue with the mounting or alignment. Additional test to losen the screws mounting the drivetrain did not work, motor would not run in closed loop on velocity 10.
Test 3:
Took apart one of the bad motors (L3) from the fixture to test seperately from gearbox and fixture. Calibration would be succesful but motor would not exert sufficient torque when running at velocity. Same behavior as tests prior, when torque is exerted motor would lock/stop and draw current heating up the wires.
Summary of Results
R3 is likely a fixture misalignment/tolerancing issue as motor fixture runs as expected when not attached to drivetrain however doesn’t behave when it is mounted.
Other 3 motors could be broken, not enough torque. Further testing/research required to see if different drivers would help or if motors are just broken. Test results point that it is likely not a fixture or gearbox issue.
Next steps:
Test out the new spark drivers to see if they are compatible with the motors and if we are getting same results as the odrives
Take out the test motor and mount it to the fixture to see if that one works, if thats the case maybe buy replacement motors.
Outstanding tickets:
- <action name>, <Assignee>
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