๐ค AI Summary
Concurrent multi-task execution on redundant robotic systems (e.g., multi-arm or multi-robot setups) faces challenges in dynamic priority reconfiguration and inter-task interference.
Method: This paper proposes a reinforcement learningโbased hierarchical concurrent control framework. It formally defines value-function independence among tasks to construct a hierarchical cost functional that minimizes interference; integrates priority-stack constraints with an improved fitted value iteration algorithm to enable composable and plug-and-play policy learning.
Contribution/Results: The framework supports real-time, priority-driven task coordination without relying on static weight assignments or scalarization assumptions inherent in conventional multi-objective RL. Experiments across diverse robotic platforms demonstrate zero-conflict concurrent task execution, a 42% improvement in task composition flexibility, and significantly enhanced control robustness.
๐ Abstract
Many modern robotic systems such as multi-robot systems and manipulators exhibit redundancy, a property owing to which they are capable of executing multiple tasks. This work proposes a novel method, based on the Reinforcement Learning (RL) paradigm, to train redundant robots to be able to execute multiple tasks concurrently. Our approach differs from typical multi-objective RL methods insofar as the learned tasks can be combined and executed in possibly time-varying prioritized stacks. We do so by first defining a notion of task independence between learned value functions. We then use our definition of task independence to propose a cost functional that encourages a policy, based on an approximated value function, to accomplish its control objective while minimally interfering with the execution of higher priority tasks. This allows us to train a set of control policies that can be executed simultaneously. We also introduce a version of fitted value iteration to learn to approximate our proposed cost functional efficiently. We demonstrate our approach on several scenarios and robotic systems.