ROBUST CONTROL OF LASER ACTUATOR FOR TECHNICAL VISION SYSTEM

Abstract

Context. The SLAM problem solving for an autonomous mobile robot requires efficient technical means for surrounding terrain scanning with the purpose of its mapping and obstacles detecting. As such means, laser scanning systems are widely used both independently and in combination with other tools as a part of a uniform technical vision system of a mobile robot. One of the problems with a technical vision systems operation is the ability to detect relatively small obstacles, which requires scanning of a limited sector within the field of view or even focusing on a specific point of space. This study is devoted to the issue of improving the reliability of obstacles detecting within the robot field of view by improving the laser actuator of the technical vision system. Objective. The objective of the work is to the reliability increasing of obstacles detection within the robot technical vision system field of view due to the robust control of the actuators of the positioning system of the laser. Method. The classical PD-controller for the laser positioning actuator, which meets the requirements for the quality of the transient process, has been synthesized. The evaluation of robust properties of the obtained control system showed both a significant dependence of the actuator dynamic properties on the variation of the values of the actuator model parameters and the potential possibility of its time response increasing. With the help of the MATLAB Robust Control Toolbox, the controller gains have been redefined to ensure the robust properties of the control system. The analysis of the influence of parametric uncertainties of the actuator model on the system dynamic properties is conducted. Results. A robust PD-controller for the laser beam positioning system actuator for the technical vision system has been synthesized. It combines the simplicity of the implementation of a classic controller with a weak sensitivity to the uncertainties presence. Conclusions. The using of the controller at the mobile robot laser technical vision system will increase the reliability of obstacle detection and, as a result, the accuracy of mapping of a limited sector within the robot field of view under the conditions of the parametric uncertainty of the actuator model.