1) Mobile Robot Teleoperation

In this research several interfaces for teleoperation of a mobile robot are described and analyzed.

We consider teleoperation of a wheeled mobile robot when control commands are given by human operator through a master device. Phantom Premium 1.5A from SensAble Technologies, Inc. was used as a master device. We implemented our control ideas to the Activmedia Pioneer 3-DX mobile robot.

CONTROL STRATEGIES

Position-speed and position-position command strategies were used for mobile robot teleoperation. In position-position strategy desired speed of a mobile robot is defined by a master manipulator’s position. In position-speed command strategy robot’s position is controlled by position of master device. Hybrid command strategy, combining position-speed and position-position strategy, is introduced.

FEEDBACK INFORMATION

First, unilateral teleoperation was studied. Experiments with position-speed, position-position and hybrid command strategies were evaluated.

Second, bilateral teleoperation of a mobile robot was studied using two types of force feedback: force feedback related to obstacle range information, and force feedback including information about the state of the robot. For experiments with bilateral teleoperation different command strategies were applied.

The role of vision feedback was verified also. For each type of human-robot interaction interface advantages and disadvantages, and possible applications were described.

Audio information was also introduced as one of the possible types of feedback for teleoperation systems.  Sound system was used to inform the human-operator about the obstacle in front of the robot. Intensity of this signal was increased while the robot was approaching to the obstacle. The role of sound feedback is to give additional information about the remote environment, so that the probability of collision will be decreased.

In next video, you can see mobile robot teleoperation experiment. During that experiment human-operator was asked to complete the task of moving objects in remote environment. Human-operator used switching control strategy for remote control of speed or position of the mobile robot. Completion task and accuracy of object positioning was measured. Position control mode allowed human-operator to intuitively control each displacement of robots position. It was useful for object manipulation. In speed control mode human remotely controlled speed of the robot. That allowed easy navigation in a large workspace.