In view of the complexity of the ground in the operating environment of police explosive ordnance disposal robots, a wheel-track deformed mobile robot (NEZA-I) with adaptive ability to non-structural environment was proposed and developed in combination with the motion advantages of wheeled and caterpillar mobile mechanisms. The NEZA-I consists of a control housing unit and two identical Transformable wheel-track (TWT) mobility modules. Each TWT module, under the action of a driving force, can move on the complex road in two motion modes: wheel and track, and can also change the motion mode (i.e. wheel-track interchange) and adjust the motion attitude (i.e. change the track geometry) according to the change of the ground binding force. The design method of mobile mechanism platform can not only improve the efficiency of driving motor, but also simplify the control of robot. The experiments show that NEZA-I can pass through the complex road environment with reasonable motion mode and attitude by adjusting its own mechanism, and has good environmental adaptability and obstacle crossing performance, which verifies the rationality of the design of the mobile mechanism system.