Development of Remote Control System for Field Robot

Hydraulic excavators is the representative field robot and has been used in various fields of construction. Since the excavator operates in the hazardous working circumstance, operators of excavator exposed in harmful environment. Therefore, hydraulic excavator automation and remote control system has been investigated to protect from the hazardous working environment. Remote control system of hydraulic excavator needs a various equipments which is EPPR(Electro Proportional Pressure Reducing) valve, electronical joystick, video camera and monitor for virtual environment displayer, communication equipment of between controller and the real activity. In this paper , the method to construct the remote control system is proposed. The remote control system is consisted of a manual and automatic mode. Manual mode controls a hydraulic cylinder as open loop control and auto mode controls the end effect of excavator using tracking control system. Because of interactions between links and various working conditions. MRAC (Model reference adaptive control) based on variable structure is designed in this paper. The efficiency of remote control system was evaluated through the field test.