Falcon Motors Stalling on Power Cells

Team 395’s Falcon motors are stalling on power cells in our shooter chamber when started from resting. Here is a video to see what I’m talking about. The accelerator wheels below the shooter wheels are powered by one NEO on a 3:1 reduction and lower compression, and the NEO spins up fine with a ball pre-staged. The shooter wheels (~0.5 lb), powered by 2 Falcons 1:1, stall with a ball prestaged at 2" of compression (in the video, the ball is in-between the accelerator and shooter and is in a slight deadzone where neither set of wheels is compressing >0.5"). We observed this even at full power. We shoot balls satisfactorily when it gets to speed.

We aren’t freaking out about this; we don’t think this scenario falls into our use cases. But we are still curious as to what would be the cause of stalling. Is this expected behavior? Or could there problems with our system (mechanical or controls) that we can troubleshoot?

I would expect that behavior…but you can probably figure out a way to measure the torque it takes to turn the shooter wheel. with a PC in place, using a spring scale, and, you can compare that to the specification stall torque for the motor.

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We had this issue when our feeder wheel sent a ball into the shooter before the shooter wheel had started up. We have since put in code that keeps the feeder wheel from doing that when the shooter wheel is less than a certain speed.

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This is what we have in place now, good to know teams are encountering and overcoming the same obstacles.

I would expect that behavior…but you can probably figure out a way to measure the torque it takes to turn the shooter wheel. with a PC in place, using a spring scale, and, you can compare that to the specification stall torque for the motor.

My intuition was telling me the same but I wanted to be sure. Don’t know if we have a spring scale in the shop, but will try to take this measurement.