163 TECHNICAL UNIVERSITY OF CLUJ-NAPOCA ACTA TECHNICA NAPOCENSIS Series: Applied Mathematics, Mechanics, and Engineering Vol. 59, Issue II, June, 2016 DYNAMICS EQUATIONS FOR A CAR INSPECTION MOBILE STRUCTURE Iuliu NEGREAN, Claudiu SCHONSTEIN, Kalman KACSO Abstract: The paper is devoted to establishing the dynamics equations, by an analysis of kinematic and dynamic behavior, for a mobile robot, called RmITA. Based on geometric modeling of the structure, there will be determined the kinematic constraints that affect the structure. Also, the mathematical model used to determine the dynamics equations, will be based on new concepts in advanced mechanics, based on important scientific researches of the main author, concerning the acceleration energy. In keeping the fact that the mathematical models of the mobile platforms are different besides the other robots types, due to no holonomic constraints, the dynamic control functions, will be established according to restrictions for motion. Key words: mobile robots, dynamics equations, control, acceleration energy, no holonomic constraints. 1. INTRODUCTION The development of robotic systems and their implementation in the various processes of the manufacturing or inspection, have undeniable advantages, highlighted by carrying goods, inspections of quality in less time, increasing labor productivity, accident prevention, all these issues having an important contribution to enhancing the quality of life and economic development of the users of these systems. In the paper, is considered a mobile structure, presented in the Fig. 1, able to help the human operator in cars inspection, by collecting data and send information to a computer after which, will be reviewed by an inspector, who will conclude about the state of the car. The robot is characterized by a differential shift commonly used in moving mobile robots. The structure is equipped with pan-and-tilt camera, characterized by two degrees of freedom, consisting in two rotations as can be seen from Fig.1. The drive wheel is done in pairs, so that the two wheels on each side are driven by a motor. Thus, the proposed differential robotic system is characterized by four wheels, powered by two engines on each side of the structure. Based on these considerations, a straight line movement of the movable mechanical structure is obtained when the pair of wheels on one side rotates at the same speed and in the same direction, with the other pair of wheels on the opposite side (see Fig.2). Fig.2 – Straight line motion of the inspection robot Fig 1 The RmITA Robot Structure