A novel unit mechanism for serial head-tail alternatively supported robot

Abstract

Multi-unit serial mobile robot designed for obstacle avoidance, inspection or rescue task, should ideally be able to switch the head and tail as supporting stand to move forward wriggly, be lightweight and low energy consumption, aiming at adapting to complex application environment. This paper proposes a novel robot pitching unit based on a parallelogram mechanism, and a robot with the proposed units taking the task of power transmission line inspection as application background. To reduce unit motor number and weight, a single motor and cable driving(SMCD) method is proposed. The unit architecture and robot prototype are designed. The kinematic model is developed and the supporting stand switch process is presented. According to the force analysis of the unit mechanisms, the driving motor energy consumption calculating methods of the proposed unit and the conventional serial unit are presented respectively. The low energy consumption characteristic of the proposed unit is demonstrated through applications respectively on a 4-unit serial immobile robot model and an inspection robot model for power transmission line. Experiments of unit supporting stand switch and robot prototype crossing obstacles are conducted to verify the unit feasibility. The results of analysis and experiments show that comparing with the conventional units, the whole energy consumption of the robot can be reduced clearly by applying the proposed units, the novel unit is capable of switching the supporting stand, based on which the inspection robot meets the application requirements on overhead power transmission line.