Reward shaping for reinforcement learning by emotion expressions

In this paper, a non-expert learning system was proposed to guide the robots learn their behaviors by humans´ emotional expressions. The proposed system used interval fuzzy type-2 algorithm to recognize the human´s facial expressions, which were captured by a web camera. Furthermore, emotion value (E-value), generated based on non-expert human´s facial expressions, was applied to the reinforcement learning to train robots. Two kinds of problems were experimented. One was the human being know the exact solution to train robots and could clearly observe good or bad choice robots had been made. The other one was human being did not know the exact solution but robots could still learn from human´s experience. The experiment results show that no matter the learning environment could be clearly observed by human being or not, robots could learn from human´s facial expressions by the proposed learning system.