Jaguar Lights

[DonRotolo]

Originally Posted by Tanner

what else would cause this erratic inability to drive well?

Goodness, many things.

For one, does everything seem to work OK when the wheels are in the air? Run the drivetrain like that for a while, to break in the gearboxes (and, to a lesser degree, motors). 30 to 60 minutes of unloaded movement will help.

Next, what's the robot configuration? If you have 4 wheels, one in each corner of the robot, and are trying to turn with high-traction wheels - you may be popping breakers. That's about the worst-case for turning. Does it drive well when you go in only straight lines (no turns)?

The gear ratio also affects this - very high ratios (slow speeds) allow better turning. Low ratios don't leave enough torque to turn well, even with 6 or 8 wheel drive.

Lastly, check the system voltage while the problem is present. Voltages dropping to less than 10.5 volts or so may indicate a wiring or battery charge issue. Run all the motors (off the ground) and, using a voltmeter. find where the voltage drops are. From the - battery terminal (the metal of the battery itself, NOT what you have connected to the terminal!) to the PDB it should be very small; similarly, from the + terminal to the PDB should be almost the same (we expect a larger voltage because of the main circuit breaker). Then from the PDB input bolts to the input screws of the Jaguars (one at a time).

If you find a high voltage (as compared to the rest of them, assuming at least one is "good") you need to correct it. Voltages around 0.1 to 0.5 are in the range I'd expect.

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