Perturbation controller

[marco xu]

Hi Dr. Thomas Geijtenbeek:
Thank you for your time. I'm writing to report a question while doing the tutorial 4(perturbaiton gait) simulation. I changed the 'force' to 'moment' during simulation, however, I didn't see any influence of this moment added on the body(while 'force' worked out well), and I see the red arrow exerted on the body during the gait. Is there any reason for this? Thank you for solving this!

Regard

[Thomas Geijtenbeek]

I tried it and it works well for me. Just make sure the moment is applied around the Z axis, when the simulation is planar. This is the code segment I used:

Code: Select all

PerturbationController {
	name = PushBack
	start_time = 3
	duration = 0.1
	interval = 4
	moment = [ 0 0 150 ]
	body = torso
	# position_offset = [ -0.05 0.35 0 ]
}

[marco xu]

Thanks for the reply, I just made a mistake on the direction. So the arrow direction is determined by the right-hand rule right?
Thank you so much for your detailed reply. Many thanks.

[Thomas Geijtenbeek]

Indeed, moment direction is according to the right-hand rule. Good to hear it works!