Online navigation of mobile robot under the existence of dynamically moving multiple obstacles

Abstract

Proposes an online navigation method of mobile robots for collision avoidance with dynamically moving obstacles, where the multiple obstacles always change their velocities. For more applications of mobile robots in the real world, the robots are expected to work well in everyday space where people are walking around. The robot must reach the desired point even in a dynamic environment where many people (obstacles) are moving. In such a situation where the environmental objects are dynamically changing their position, it is not realistic to have all information of the dynamical environment such as trajectory of a human being's motion. To cope with the situation, the robots usually have a sensor system to obtain real time environmental information, and robots should have an ability of sensor-based online motion planning for the dynamical environment. The paper considers the online motion planning problem where the workspace has multiple moving obstacles. The proposed motion planner basically uses an idea of velocity obstacle. After discussing some problems when applying the idea of velocity obstacle to online motion planning problem for dynamical environment, a modified method using the idea is presented. The main point of the modification is for coping with velocity changes of moving obstacles during the sensor cycle. The paper also discusses the efficiency of the resultant trajectory produced by the motion planner. Some simulations of online motion planning problems where multiple obstacles are changing their velocities are shown.