PPM median filter causes glitch on startup without safe_start

[Teslafly]

The Vesc is used heavily in battlebots robots. They generally use ppm servo input, and have to turn safe start off because you often get a fault when you get hit, and the time it takes for ppm safe start to recover is not acceptable. You get faults, but generally do not reboot.

This means you pick up the glitch from median filter equalizing on startup because you can't use safe start. This causes the motors to twitch on a very big and dangerous robot.

There are probably several ways to solve this:

• Have vesc tool option to not trigger safe_start on motor fault (extra condition in app_ppm.c, line 167)
• When ppm app starts, throw out the first few readings. regardless of safe start setting while the filter equalizes.
• Init the median filter with the first good pulse.

Thoughts? I can probably implement the "don't trigger safe start on motor fault" option.

[Teslafly]

fixed by no safestart on fault option.