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arXiv · 2606.26313

Racing a Wheeled Quadruped: Active Load Transfer Mitigation via Model Predictive Control

Marla Eisman·Brian Lam·Samuel Sonnino·Francesco Borrelli
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Abstract

This paper presents a hierarchical control framework using model predictive control (MPC) and reinforcement learning (RL) for active roll control to manage lateral load transfer during autonomous racing of a wheeled quadruped. The framework integrates offline time-optimal raceline generation, an online MPC planner that actively minimizes the lateral Load Transfer Ratio (LTR), and a low-level, whole-body RL policy deployed directly onto the robot's 16 actuators. The MPC is based on a vehicle dynamics bicycle model of the Unitree Go2-W platform. The robot's leg actuators act as active suspension where knee joints generate anti-roll torque to bank into turns. Physical track experiments demonstrate that active roll control reduces mean LTR by up to 44%, improves the fastest lap time by 8.7%, and boosts peak lateral acceleration capability by 21.3% to 1.98 $m/s^2$, maintaining robust high-speed stability beyond the range of a non-tilting baseline controller. Supplementary code and video can be found at https://github.com/meisman-ucb/go2w-roll-control-mpc

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Marla Eisman, Brian Lam, Samuel Sonnino, Francesco Borrelli. 2026-06-24. Racing a Wheeled Quadruped: Active Load Transfer Mitigation via Model Predictive Control. https://arxiv.org/abs/2606.26313

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