Is Linear Feedback on Smoothed Dynamics Sufficient for Stabilizing Contact-Rich Plans?

• URL: http://arxiv.org/abs/2411.06542v4
• Date: Wed, 14 May 2025 11:58:21 GMT
• Title: Is Linear Feedback on Smoothed Dynamics Sufficient for Stabilizing Contact-Rich Plans?
• Abstract summary: This paper analyzes the efficacy of linear controller synthesis using differential simulators based on contact smoothing.<n>We perform empirical experiments on over 300 trajectories and analyze why LQR seems insufficient for stabilizing contact-rich plans.
• Score: 26.26239969660602
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Designing planners and controllers for contact-rich manipulation is extremely challenging as contact violates the smoothness conditions that many gradient-based controller synthesis tools assume. Contact smoothing approximates a non-smooth system with a smooth one, allowing one to use these synthesis tools more effectively. However, applying classical control synthesis methods to smoothed contact dynamics remains relatively under-explored. This paper analyzes the efficacy of linear controller synthesis using differential simulators based on contact smoothing. We introduce natural baselines for leveraging contact smoothing to compute (a) open-loop plans robust to uncertain conditions and/or dynamics, and (b) feedback gains to stabilize around open-loop plans. Using robotic bimanual whole-body manipulation as a testbed, we perform extensive empirical experiments on over 300 trajectories and analyze why LQR seems insufficient for stabilizing contact-rich plans. The video summarizing this paper and hardware experiments is found here: https://youtu.be/HLaKi6qbwQg?si=_zCAmBBD6rGSitm9.

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