Honda - add pitch compensation to Nidec

[mvl-boston]

Honda Nidecs benefit from pitch compensation for gas and brake. Have been testing this for a month on an openpilot fork.

Adding this change in a similar manner as the Bosch change in earlier versions of #2488

Todo:

• Await upstream of Honda: Honda Odyssey 2021-25 #2488
• Rebaseline with any further changes in Honda: Honda Odyssey 2021-25 #2488
• Separate PR needed to fix gas control, to make the impact of this fix more obvious in a test route
• Create pre and post testroutes with this fix

[mvl-boston]

Putting this on hold as test route is not obviously better. Need to move from speed control to gas pedal control to make impact more visible, staying as draft until a PR for pedal control is working.

[sshane]

I had tried to add pitch compensation to Toyota when trying to understand and undo the internal PCM compensations it does to our acceleration request, but was never able to get it working reliably in all scenarios.

Highpassing (~derivative) the pitch, and then allowing the integral controller to wind up after pitch changes worked much more reliably and more responsively. It removed any steady state error if the pitch estimation was wrong, or if the factor to go from pitch -> accel (gas/brake in your case) is totally unknown.

Unclear if it would benefit you here, but you can copy what I did for Toyota and report back:

opendbc/opendbc/car/toyota/carcontroller.py

Lines 231 to 234 in fce60b4

	high_pass_pitch = self.pitch.x - self.pitch_slow.x
	pitch_compensation = float(np.clip(math.sin(high_pass_pitch) * ACCELERATION_DUE_TO_GRAVITY,
	-MAX_PITCH_COMPENSATION, MAX_PITCH_COMPENSATION))
	pcm_accel_cmd += pitch_compensation