Kinematics Analysis of a Four Legged Robot Suspended on Wire

Some theoretical and experimental studies have been developed to obtain independent equipment for inspection and maintenace of electric and communication lines, allowing to increase the efficiency of the process and to reduce the risk of accidents with the employees who execute the task. This activity is perfectly adequate for mobile robots because they are capable to move in avoiding the existing obstacles on the cables. The more important mechanical characteristic of the mobile robots is related with its stability, that are in two types: the static stability that is its capacity to maintain a configuration from reaction forces; and the dynamic stability that is its capacity to maintain a configuration from reaction forces and inertia forces. In this paper we present the kinematic analysis and the project of a robot with four legs to move suspended on wire. The kinematic analysis have been developed by considering the capability of the robot in transposing obstacles on the wire. For that, two analysis have been made: the first one considers all legs having equal lengths and, the second one unequal lengths. The analysis enable to verify the maximum obstacle dimension that the robot can transpose, when the obstacle doesn't occupe the foot position when it returns on the wire. Simulations of the legs and the robot behavior have been carry out using graphical software. Results of the mathematical model and simulations are presented.