Hold Climber Position with Motor Stalls

[karagenit]

Here's my thought:

GamepadClimberControl: when the joystick input is between 20% and -20%, we engage the brake and set the motors to a known stall power (e.g. 15%).

Has the downside of possibly triggering the pneumatics a lot if we're holding the stick right around 20% (we could disengage at 30% and engage at 20% to prevent that).

[paul-blankenbaker]

I like the 20% engage and 30% dis-engage range. However, I think the output power needs to be compensated based on whether you are going up or down (a gain multiplier):

final static double UP_GAIN = 1.0; // Allow full power going up
final static double DOWN_GAIN = 0.25; // Greatly reduce max power when going down

// Do you new checks on enable/disable brake
// Then apply gain setting to ouput power based on direction
power = (power > 0) ? power * UP_GAIN : power * DOWN_GAIN;

[karagenit]

I don't know if the "gains" will be necessary - I plan on simply setting peak outputs on the Talons to limit the speed when climbing.

Anyway, I hope that none of this stall + brake stuff will be necessary. Ideally, we'll fix the brake such that it's able to hold the robot completely on its own. We readjusted it a bit ago, and I plan on testing it tomorrow. I'll probably implement this change in a branch, so we can merge it in if the brake isn't good enough.