In recent years, mobile robot teleoperation has made great progress with the aid of recent advancement of wireless communication technology. There are many potential applications of remote-controlled mobile robot such as construction machine, automatic vehicle, underwater exploration, mining machine, robot control by mobile devices, and universe exploration rover. However, when an operator tries to control a robot over the conventional wireless network, data transmission delay becomes a serious problem; in particular, a time-varying delay is caused by video data transmission.

We propose a novel teleoperation method in order to overcome the difficulty of remote control under transmission time delay over the wireless network. The proposed method allows the operator to control a mobile robot without being concerned about communication time delay. The operator controls a mobile robot by observing a video sequence generated from the past images that are captured by an on-board omni-directional camera on the robot. In addition, the mobile robot is operated in a manual or autonomous manner, which changes dynamically, according to the surrounding situation.

The term of adaptive teleoperation is used in bilateral teleoperation systems, and transparency is regarded to quantify the telepresence performance in the task environment. Operating a mobile robot over the wireless network is quite different in terms of the delay characteristics and reliability. The communication delay is inevitable and not expected in advance.

We, therefore, introduce an adaptive teleoperation method that allows the robotic system to change the level of autonomy in accordance with situation, which is based on the concept of situation-adaptive automation. The system delegates the priority of control to the operator or the autonomous robot according to the situation such as distance to obstacles, unknown regions, and distance between the directed location by the operator and the current location of the real robot. In the developed control system, the robot precedes the operator’s command and decides its own path based on the on-board sensors by preserving the consistency of the operator’s control and the displayed image sequence to the operator. The situation-adaptive teleoperation is regarded as the mixture of direct supervisory control and autonomous operation.