Generation of basic emotions for virtual human in the virtual environment

Will it become more natural and believable if a virtual human has emotions like a real human? The answer must be YES. This paper studies a method to simulate human´s basic emotions according to Basic Emotion Theory and Cognitive Evaluation Theory in Psychology, based on Fuzzy Rules. At first, `emotion factor´ is generated according to the emotion elicited rules based on Fuzzy IF-THEN rules. Then the emotion intensity is computed by a nonlinear function restricted by personality, emotion factor and emotion state at the previous moment. The simulation by MATLAB shows, this method can simulate the fuzzy and nonlinear characteristic of human emotion to a certain extent. The method is also applied in a virtual human, who looks like full of emotions and act as a real human.