Kinematics and Autoregressive Model Analysis of a Differential Drive Mobile Robot

The usage areas of mobile robots continue to increase due to the wide variety of advantages they provide. In particular, differential drive mobile robots (DDMR) have been widely preferred in the last decade due to the benefits they offer in current studies and the potential they promise. Before using them in advanced studies, it is quite useful in many ways to conduct basic kinematic investigation that can provide key information about these robots. This not only saves time and money, but also directly affects the accuracy of these studies. In this study, kinematic analysis of a small DDMR driven by servo motors was carried out with basic locomotion tests and system identification. The mobility of the robot along the predefined and geometrically expressible routes was examined and its kinematic limits were tried to be determined. Through the system identification tests, the consistency of the robot's response to the input commands was investigated and the possible causes of errors were discussed. Moreover, the behavior of the robot was modeled and compared with parametric ARX (autoregressive with external input) model due to its simplicity and efficiency. As a result of the motion tests, it has been observed that the robot has some limitations in rotational movements. With the system diagnostic tests, it has been determined that the two main wheels of the robot produce different outputs to the system inputs.