Efficient Exploration in Side-Scrolling Video Games with Trajectory Replay

Abstract

Deep Reinforcement learning agent has outperformed human players in many games, such as the Atari 2600 games. In more complicated games, previous related works proposed a curiosity-driven exploration for learning. Nevertheless, it generally requires substantial computational resources to train the agent. We attempt to design a method to assist with our agent to explore the environment. By utilizing prior learned experience more effectively, we develop a new memory replay mechanism, which consists of two modules: Trajectory Replay Module to record the agent moving trajectory information with much less space, and the Trajectory Optimization Module to formulate the state information as a reward. We evaluate our approach with two popular side-scrolling video games: Super Mario Bros and Sonic the Hedgehog. The experiment results show that our method can help the agent explore the environment efficiently, pass through various tough scenarios and successfully reach the goal in most of the testing game levels with merely four workers and of ordinary CPU computational resources for training. The demo videos are at Super Mario Bros and Sonic the Hedgehog.