A Parent-Children Type Robot System for Scout: Mechanics, Control, Simulation and Test

The mechanics and control specifications of a parent-children type robot system currently being built at Harbin Institute of Technology is proposed. The parent robot platform, called HIT-HYBTOR, weights about 25 kilograms, has four legs and wheels on its feet so that it can walk and step over barriers on rough terrain or drive by wheels accessing more speed on even ground. The power for leg joint motion, as well as for the wheels, is got from actuators with MAXON DC-motors. The children robot, called HIT-WORM, weights about 0.5 kilograms, has two legs and four MAXON DC-motors, and moves like inchworm. The parent robot can transport several children to the place near destination then release them. Then the children begin scout task cooperatively. To master the control task of HIT-HYBTOR and HIT-WORM, hierarchical hardware architecture was implemented with two levels: the microprocessor level and the PC level. The microprocessor level is responsible for the low-level control of the legs, the wheels and the body movement, of course, receive the sensor data too. The PC level controls the complete movement of the HIT-HYBTOR like trajectory planning and leg coordination. For the communication between the units of the microprocessor level and the PC level, a CAN-bus device is used. Locomotion ability of the parent robot and children is simulated. Walking experiment is given