Help with weird problem.

[Xenozero]

well it does help a little, there is actually dipit on the cloth itself (oddly enough to try to gain some friction for the orbit balls) but we did try the static theory out by connecting a copper wire to the closest metal contact to the rollers and the moter speratly and connecting the other end to a ground, the negetive lead of the input voltage.

with the current theorys brought forth, they all have their counter points

- current draw spike
*when the motor was disconected from the belt it was driven fine as long as we wanted, but when conected again to see if the current did spike, the device we used to measure the current draw on the system did not spike above 16 amps, with the occasional 20 amp reading for a split second

-static theory
* the combonation of the metal rods making a vandergraf generator causes the static charge to spike and discharge resulting in a system failure.
this was tested against multiple grounds connected to key points on the system and still the problem accurs

-vibration theory
* the vibration of the robot results in the disruption of the ethernet cord and therefore forces the watchdog to shut the speed controllers down.
- the motor and belt in question does not vibrate more then the other components that do vibrate alot more and can run for as long as we like.

Temperature theory
- the motor did not heat up at all through out the days use

Dead battery theory
- the battery was changed multiple times

if i missed one please help lol. this problem is really stumping alot of people and im glad everyone is helping

[Russ Beavis]

You should also make sure that your DSC is connected to a red/black WAGO pair on the PD with a 20A breaker. We've seen teams used the camera power port instead (which is only 5V and therefore causes the DSC to brown out very easily).

Also make sure that you're getting a full 12V to the DSC. All 3 power LEDs near the power jack must be fully lit. If not, you've probably crimped some insulation instead of copper at the PD's WAGO connections and are being intermittently powered via the 37-pin ribbon cable to the cRIO (which can provide a couple of milliamps and fool you into thinking everything is fine until you try to drive a larger number of speed controllers or spikes).

Russ

[Al Skierkiewicz]

Xeno,
There is a good possilbity that your battery wiring is faulty. Check to see that all hardware is tight and all crimps are secure. Pull and tug on the wiring from the battery to breaker to PD. The 120 amp breaker may also be defective. With the robot on, try lightly tapping the red button, if the lights on the robot flicker, replace the breaker. You may also try tapping the body of the main breaker with a screwdriver handle to see if it is intermittant. We had a bad breaker in KOP this year that failed when tapped on the body. Double check your voltge readout on the DS, does it stay at 12 volts when you try things out? A small variation is normal when the robot is not running on the floor.
There are a few things that would point me to change the CIM motor. Although highly unlikely, there is a possibility that there is a defect in the CIM such that once the temperature starts to rise internally, the motor shorts. When you run it with no load, the temperature doesn't rise nearly as fast as when you you load it. To isolate, remover the breaker for that motor and run the robot. Does the condition reoccur? If not, that points to the motor or the motor wiring.
Finally, the resistance reading to chassis is fine if it is over 100,000 from any terminal on the PD with the battery disconnected. You can have a 40 meg ohm reading with someone touching the chassis.