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arXiv · 2410.01030

Preferenced Oracle Guided Multi-mode Policies for Dynamic Bipedal Loco-Manipulation

Prashanth Ravichandar·Lokesh Krishna·Nikhil Sobanbabu·Quan Nguyen
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Abstract

Dynamic loco-manipulation calls for effective whole-body control and contact-rich interactions with the object and the environment. Existing learning-based control synthesis relies on training low-level skill policies and explicitly switching with a high-level policy or a hand-designed finite state machine, leading to quasi-static behaviors. In contrast, dynamic tasks such as soccer require the robot to run towards the ball, decelerate to an optimal approach to dribble, and eventually kick a goal - a continuum of smooth motion. To this end, we propose Preferenced Oracle Guided Multi-mode Policies (OGMP) to learn a single policy mastering all the required modes and preferred sequence of transitions to solve uni-object loco-manipulation tasks. We design hybrid automatons as oracles to generate references with continuous dynamics and discrete mode jumps to perform a guided policy optimization through bounded exploration. To enforce learning a desired sequence of mode transitions, we present a task-agnostic preference reward that enhances performance. The proposed approach demonstrates successful loco-manipulation for tasks like soccer and moving boxes omnidirectionally through whole-body control. In soccer, a single policy learns to optimally reach the ball, transition to contact-rich dribbling, and execute successful goal kicks and ball stops. Leveraging the oracle's abstraction, we solve each loco-manipulation task on robots with varying morphologies, including HECTOR V1, Berkeley Humanoid, Unitree G1, and H1, using the same reward definition and weights.

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Prashanth Ravichandar, Lokesh Krishna, Nikhil Sobanbabu, Quan Nguyen. 2024-10-01. Preferenced Oracle Guided Multi-mode Policies for Dynamic Bipedal Loco-Manipulation. https://arxiv.org/abs/2410.01030

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