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[technik3k]

Reserved for V5 in-depth system troubleshooting topic 1

Motor commands and dynamic power limiting information:

How does the decreased current affect the robot when using more than 8 motors

vexos 1.0.9 uses a different algorithm than versions 1.0.8 and earlier. 8 or less motors are still capped at 2.5A. 9 or more are capped as follow, remember this is current at the motor not current from the battery, 9 2.39A 10 2.29A 11 2.20A 12 2.12A 13 2.04A 14 1.98A 15 1.91A 16 1.85A 17 1.80A 18 1.74A 19 1.69A 20 1.65A However, those values are only valid if user code has not set current limit lower on one or more motors. If that has happened we take the user specified lower motor curren…

How does the decreased current affect the robot when using more than 8 motors

so most of the time teams are not sending a voltage to the motor but rather a requested velocity. Even when the motor is told to stop, it may be using a significant amount of power depending on the brake mode of the motor. The current limiting happens inside each motor, even when we limit continuous current to 2.5A, the transient current can be much more than that and the motor needs to respond quickly to these changes. Individual motors don’t have knowledge of what all the other motors are …

V5 motor configuration upon reconnect

It’s a feature (bug really) of PROS. vexos keeps the configuration for flags like reverse if the motor is not present when user code starts or is unplugged, however, PROS doesn’t send it though on startup if it thinks there is no motor, VEXcode however does. The things we keep backup values for are brake mode encoderUnits gearset reversed currentLimit voltageLimit One reason for keeping these values is safety, I didn’t want a motor running at full power when user code had aske…

V5 motor configuration upon reconnect

That’s correct, the reverse flag is handled by vexos and not sent to the motor, it’s much easier to handle things like updating the current motor position when user code changes the reverse flag while the motor is running (why you would want to do that I don’t know, but some of these design decisions were taken more than 4 years ago and based on robotc functionality). yea, PROS always validates the the correct type of device is on a given port before calling into vexos