Design of Transfer Reinforcement Learning Mechanisms for Autonomous Collision Avoidance

It is often hard for a reinforcement learning (RL) agent to utilize previous experience to solve new similar but more complex tasks. In this research, we combine the transfer learning with reinforcement learning and investigate how the hyperparameters of both transfer learning and reinforcement learning impact the learning effectiveness and task performance in the context of autonomous robotic collision avoidance. A deep reinforcement learning algorithm was first implemented for a robot to learn, from its experience, how to avoid randomly generated single obstacles. After that the effect of transfer of previously learned experience was studied by introducing two important concepts, transfer belief—i.e., how much a robot should believe in its previous experience—and transfer period—i.e., how long the previous experience should be applied in the new context. The proposed approach has been tested for collision avoidance problems by altering transfer period. It is shown that transfer learnings on average had ~50% speed increase at ~30% competence levels, and there exists an optimal transfer period where the variance is the lowest and learning speed is the fastest.