Haptic interaction in tele-operation control system of construction robot based on virtual reality

In this paper, a tele-operation control system of construction robot (TCSCR) with the master-slave control form is presented, which consists of a construction robot controlled by servo valve, and two joysticks for operating the robot from a remote place, and 3-dimensional virtual working environment based on the virtual reality technology. The tele-operation technology employing virtual reality, improves the task efficiency of a conventional TCSCR by giving the operator a feeling of being at the actual operate site in real-time. However, for those without experience person, it is dangerous to operate and manipulate a remote construction robot (RCR). It is reported that the toppling accident of RCR rose especially. The reason that toppling accident occurs is that the reception desk of RCR continues working even though it is unstable state or comes in contact with an obstacle. To prevent RCR from falling into the unstable state or coming in contact with the obstacle and enhance the security of the operation, the haptic interaction is introduced into TCSCR based on the virtual reality technology. The reaction force will be calculated using the preprogrammed rules and conveyed to the operator by the joystick once a haptic interaction happens, which suggest that a danger exists in the operating of RCR. At last, an experiment is carried out on the tele-operation construction robot test-bed, the experiment results indicate that the tele-operation construction robot system with the haptic interaction can improve operability, security and reduce the toppling accident.