A reconfigurable mobile microrobot actuated by electromagnetic micromotors is presented.A flexible passive universal connector is designed.Multiple basic microrobots can be connected with each other manually to form a passive trailer with automatic disconnecting function,and their whole surveillance range can be enlarged by adopting the method of power and wireless communication relays.To reduce the tracking error of the passive trailer,relationship between the errors and the lengths of the front and back link rods of the passive connector is revealed by kinematics analysis,and the related kinematic equation and control method are derived.The experimental results demonstrate the feasibility of the concepts.