Kinematics-Aware Multi-Policy Reinforcement Learning for Force-Capable Humanoid Loco-Manipulation

Abstract--Humanoid robots, with their human-like morphology, hold great potential for industrial applications. However, existing loco-manipulation methods primarily focus on dexterous manipulation, falling short of the combined requirements for dexterity and proactive force interaction in high-load industrial scenarios. T o bridge this gap, we propose a reinforcement learning-based framework with a decoupled three-stage training pipeline, consisting of an upper-body policy, a lower-body policy, and a delta-command policy. T o accelerate upper-body training, a heuristic reward function is designed. By implicitly embedding forward kinematics priors, it enables the policy to converge faster and achieve superior performance. For the lower body, a force-based curriculum learning strategy is developed, enabling the robot to actively exert and regulate interaction forces with the environment. T o ensure robust whole-body coordination, a delta-command policy is employed to counteract vertical end-effector displacements in the world frame resulting from lower-body motion. Extensive simulation and real-world experiments on the Unitree G1 humanoid robot validate the proposed framework, showcasing its capability to accomplish high-payload tasks such as walking while carrying a 4 kg object and pushing or pulling a cart with a total load of 112.8 kg. UMANOID robots are increasingly considered for deployment in industrial settings, where various tools and workflows are originally designed for human operators. As large-scale customization is often impractical, humanoid robots, owing to their morphology and natural operational compatibility, can seamlessly interface with and utilize existing tools.