Abstract: To access to the complex and unpredictable environment where the ground is soft and hard alternately, a transformable wheel-track (TWT) robot with a self-adaptive mobile mechanism, named as NEZA-I is proposed and developed. It has the merits of both the wheel mechanism and the track mechanism. The robot NEZA-I consists of a control system unit and two symmetric TWT units. Driven only by one servo motor, each TWT unit can efficiently cross over the complex terrain by wheel mode or by track mode, and can also change its locomotion mode and adjust its posture according to the constraint of the environment. The proposed mechanism can improve the motor service efficiency and simplify the control of robot. Experiments show that the robot can efficiently cross over complex terrain by changing autonomously the locomotion mode and posture, and has prominent adaptability to environment and obstacle-surmounting ability. The results prove the rationality of the design of the mobile mechanism system.

Key words: Adaptive mobile mechanism, Mechanical design, Transformable track, Wheel-track robot