Sensorless contact position estimation of a mobile robot in pushing motion

Manipulating mobile robots on a pre-defined path is a challenging task when there are unknown objects on its path. Most of the manipulators use gripping methods to move such obstacles. In this research, an object to be pushed in a predefined path is considered. Estimation of the point of contact is important to control the mobile robot in its desired path. This paper introduces a novel concept called Contact Position Estimator (CPE) to calculate the point of contact when the robot is moving on the said path. CPE estimates the position using the reaction torque observer and the estimated torque, which is a sensorless method of estimating the torque, was used. Results show the applicability of the proposed concept.