The design and experiments of a small wheel-legged mobile robot system with two robotic arms

In this paper, we developed a small wheel-legged mobile robot system, which could walk on different road environments using wheels or legs. It is composed of mechanical, sensor and control subsystems. The mechanical subsystem includes a wheel-legged mobile platform, a rigid robotic arm and a flexible arm. The mobile platform provides a variety of movement ways to meet the requirement of different mobility. The rigid arm (denoted by arm-a) is a serial manipulator with 4-DOFs. It can be used to grasp and manipulate payloads. The flexible arm (denoted by arm-b) is a manipulator with continuous curve, and a camera is mounted on arm-b. So it can be used to provide visual inspection and measurement information. The sensor subsystem is composed of ultrasonic sensors mounted on the platform and a WIFI camera mounted on arm-b. It provides measurement information and visual inspection for remote control. The control subsystem includes an embedded controller and a PC computer. The former is developed based on an ARM microprocessor, on which the real-time operation system-RT-Thread system runs. The mission decomposition and trajectory planning algorithms are programed in C language and run in the PC. At last, typical experiments are performed. Experiment results verified the robot's mobility, operation capability and remote-control function.