Reversing needs to choose the right signs for articulation as acos is…#2
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zeerekahmad merged 6 commits intomainfrom Mar 18, 2026
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… multivalued and we didn't properly account for the sign there. For bicycle controller we should be using tan i nstead of atan2 as we want to be between -pi/2 and pi/2 and not in all 4 quadrants with atan2
davidt315
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Mar 18, 2026
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The articulated controller is not properly accounting for the ambiguity of acos(x) which is has multiple sign branches. This leads to a bad outcome for reversing data.
The bicycle controller is using atan2 instead of tan, which gives data in the wrong quadrant when reversing resulting in bad data. We need to be between -pi/2 and pi/2 rather than between -pi and pi. Tangent is the more correct use here.
The corrected versions seem to have reasonably correct steering angles relative
