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Integral tie-back in AtlasPlugin.cpp seems wrong - causes control glitches

asked 2013-04-09 18:22:28 -0600

GoRobotGo gravatar image

updated 2013-04-09 19:28:13 -0600

hsu gravatar image

The code at roughly line 1066 in AtlasPlugin.cpp appears to be wrong. Specifically, it generally will invert the kiq_i term on a step change and saturate in the opposite of the commanded direction.

If a negative step is applied that results in a clamped force then the code can result in a kiq_i that is clamped at the positive limit. This results in a joint excursion in the opposite of the desired direction.

This is not a desired behaviour. I would recommend simply removing the problematic code.

// lock integral term to provide continuous control as system moves
// out of staturation
this->errorTerms[i].k_i_q_i = math::clamp(
        this->errorTerms[i].k_i_q_i + (forceClamped - forceUnclamped),
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answered 2013-04-09 19:28:50 -0600

hsu gravatar image

please continue discussion on ticket.

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Asked: 2013-04-09 18:22:28 -0600

Seen: 196 times

Last updated: Apr 09 '13