Modeling, development, and evaluation of a micro-robot equipped with vibratory actuator

The aims of this research paper are modeling, control and development of a mobile micro-robot equipped with vibratory actuators and investigating the effect of stiffness of microrobot's bases as well as friction coefficient on the robot dynamics. Accordingly, the motion principle of stick-slip is used and two small vibrating motors are utilized to run this micro-robot. First, the differential equations governing the micro-robotic platform are extracted and analyzed. Then, friction forces are calculated by modeling the micro-robot as a lumped system, consisting of three point masses connected together via stiff springs. Next, using mechanical and electrical coupled equations, an appropriate model for the vibratory actuators is obtained. In the next step, simulation process with SIMULINK and MATLAB is carried out and the simulation results are presented. Afterward, the influences of the stiffness of robot's bases as well as the friction coefficient on the motion of robot are investigated. A proportional-integral-derivative (PID) controller is applied to the micro-robot to precisely control its motion. Finally, the construction process and experimental evaluation of the micro-robot are presented. According to the simulation result, the positioning accuracy of the micro robot is about 17 m at its maximum translational velocity. Furthermore, a translational velocity of about 4mm/s corresponding to the reference voltage of 1 V is acquired using experiment.