Paper ID: 2404.00514

Human-Robot Co-Transportation with Human Uncertainty-Aware MPC and Pose Optimization

Al Jaber Mahmud, Amir Hossain Raj, Duc M. Nguyen, Xuesu Xiao, Xuan Wang

This paper proposes a new control algorithm for human-robot co-transportation based on a robot manipulator equipped with a mobile base and a robotic arm. The primary focus is to adapt to human uncertainties through the robot's whole-body kinematics and pose optimization. We introduce an augmented Model Predictive Control (MPC) formulation that explicitly models human uncertainties and contains extra variables than regular MPC to optimize the pose of the robotic arm. The core of our methodology involves a two-step iterative design: At each planning horizon, we select the best pose of the robotic arm (joint angle combination) from a candidate set, aiming to achieve the lowest estimated control cost. This selection is based on solving an uncertainty-aware Discrete Algebraic Ricatti Equation (DARE), which also informs the optimal control inputs for both the mobile base and the robotic arm. To validate the effectiveness of the proposed approach, we provide theoretical derivation for the uncertainty-aware DARE and perform simulated and hardware experiments using a Fetch robot under varying conditions, including different trajectories and noise levels. The results reveal that our proposed approach outperforms baseline algorithms.

Submitted: Mar 31, 2024