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arXiv · 1710.06745

Nonsmooth optimal value and policy functions in mechanical systems subject to unilateral constraints

Bora S. Banjanin·Samuel A. Burden
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Abstract

State-of-the-art approaches to optimal control use smooth approximations of value and policy functions and gradient-based algorithms for improving approximator parameters. Unfortunately, we show that value and policy functions that arise in optimal control of mechanical systems subject to unilateral constraints -- i.e. the contact-rich dynamics of robot locomotion and manipulation -- are generally nonsmooth due to the underlying dynamics exhibiting discontinuous or piecewise-differentiable trajectory outcomes. Simple mechanical systems are used to illustrate this result and the implications for optimal control of contact-rich robot dynamics.

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Bora S. Banjanin, Samuel A. Burden. 2017-10-18. Nonsmooth optimal value and policy functions in mechanical systems subject to unilateral constraints. https://arxiv.org/abs/1710.06745

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