The paper describes a gesture recognition algorithm

which can effectively recognize single-hand gestures in real

time under complex environment. The system involves a

vocabulary of 20 gestures consisted by part of Chinese sign

language letter spelling alphabet and digits. A new complexion

model has been proposed to extract hand regions under a

variety of lighting conditions. Real-time performance is due to

a novel combination of voting theory and relief algorithm. This

system is used in our mobile robot control project.