An Orientation Sensor for Mobile Robots Using Differentials

Abstract

Without access to external guidance, such as landmarks or beacons, indoor mobile robots usually orientate themselves by using magnetic compasses or gyroscopes. However, compasses face interference from steel furniture, and gyroscopes suffer from zero drift errors. This paper proposes an orientation sensor that can be used on differentially driven mobile robots to resolve these issues. The sensor innovatively combines the general differentials and an optical encoder so that it can provide only the orientation information. Such a sensor has not been described in any known literature and is cost‐efficient compared to the common method of using two encoders for differentially driven mobile robots. The kinematic analysis and the mechanical design of this sensor are presented in this paper. The maximum mean error of the proposed orientation sensor was about 0.7° during the component tests. The application of the sensor on a vacuum cleaning robot was also demonstrated. The use of the proposed sensor may provide less uncertain orientation data for an indoor differentially driven mobile robot

Localization Methods for Mobile Robots - A Review

“…Another method of odometry use a sensor that combines the clasical differentials and an optical encoder so that it can provide only the orientation information is presented in [10] (see Fig. 3).…”

“…To use the chariot as a means of determining direction, we first let the finger point to a known direction. The orientation sensor proposed by the authors of [10] consists of an optical encoder and three differentials. Modern Technologies in Industrial Engineering Also another odometry system that eliminates errors of asymmetry and the wheel slip is presented in [8].…”

“…Mechanism of the orientation differentially driven platform sensor: a) kinematic diagram; b) design of the mechanism[10] …”

Odometry Aspects of an Omni-Directional Mobile Robot with Modified Mecanum Wheels

“…Another method of odometry, using a sensor that combines the classical differentials and an optical encoder so that it can provide only the orientation information, is presented in [9]. The orientation sensor includes an optical encoder and three differentials.…”