Dynamic window based force reflection for safe teleoperation of a mobile robot via internet

The paper presents an Internet-based teleoperation system that enables a human operator to safely control a mobile robot in unknown and dynamic environments. The operator controls the robot using a joystick and a graphical user interface which displays images forwarded from the camera mounted on the robot. A sonar ring on the robot circumference is used to measure obstacle range information, and a dynamic window algorithm is used to convert that information into a force, which is than reflected to the operator´s hand via joystick, providing additional haptic information about obstacles in the robot vicinity. To overcome the instability caused by the unknown and varying time delay an event-based teleoperation system is employed to synchronize actions of the operator and teleoperated mobile robot. The experiments with the Pioneer 2DX mobile robot verified effectiveness of the developed system.