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arXiv · 2610.08441

Safe Multi-Robot Collaborative Transport Using Density Functions

Jagannath Prasad Sahoo·Sriram S. K. S. Narayanan·Umesh Vaidya
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Abstract

This paper presents a hierarchical density-based model predictive control framework for safe collaborative manipulation by multiple quadrupedal robots. The framework enables a team of robots to push a shared object to a desired pose using only the initial and goal poses, without requiring a precomputed reference trajectory. A centralized box-level MPC optimizes contact forces while enforcing a control-density constraint for goal convergence and obstacle avoidance. Each robot then solves its own distributed robot-level whole-body MPC, under a stated shared-information assumption, to track its moving contact location while accounting for static obstacles and the time-varying positions of neighboring robots. The approach is evaluated in MuJoCo using whole-body contact dynamics for two and three Unitree Go2 quadrupeds collaboratively pushing rigid objects through narrow passages. Comparisons with matched Control Barrier Function and RRT* based tracking baselines demonstrate the effectiveness of the proposed density-based formulation for push-only, force- and torque-coupled manipulation tasks. Implementation videos are available at https://jaggu2606.github.io/go2-density-mpc-pushing/

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Jagannath Prasad Sahoo, Sriram S. K. S. Narayanan, Umesh Vaidya. 2026-10-06. Safe Multi-Robot Collaborative Transport Using Density Functions. https://arxiv.org/abs/2610.08441

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