Study On Control Strategies Of An Eccentric-type Legged Hexapod Robot

Multi-legged robot is an important branch of the mobile robot which is mainly used in mountain environment and irregular terrain. Because of its high degree of flexibility and reliability, multi-legged robot is widely used for Mars detection, crater detection, disaster relief, military reconnaissance nuclear power maintenance and so on. It has great research value and practical significance. The study of multi-legged robot includes these aspects:environmental modeling, environmental awareness and recognition, positioning and navigation, path planning, motion mechanism, control systems, etc. This paper is focus on the study of control strategy of eccentric-type legged hexapod robot. The content includes structural analysis of eccentric-type legged, gait planning and static stability analysis, control systems and path planning based on improved artificial potential field. The paper introduced as follows:1. The paper firstly introduces the concepts and the parameters about the gait and analyzes the classic gait of six-legged insect based its movement principle. Then the paper gives the overall design of mechanical structure for eccentric-type legged hexapod robot and analyzes the issue of walking location of eccentric-type legged hexapod robot. After that the paper plans the three-legged straight gait, four-legged straight gait and three-legged turning gait and gives the parameter matrix of these gaits. The static stability analysis of these gaits for eccentric-type legged hexapod robot improves that the robot is static stable under constraints.2. Based on application occasion of eccentric-type legged hexapod robot and the analysis of a variety of control systems, we design the control system using microcontroller and general computer. The control system consists of bus control module, motor control module, power module, wireless control module, wireless video transmission module and PC control module.3. In the aspect of path planning, eccentric-type legged hexapod robot uses the improved artificial potential field model. The model avoids the local minimum point by changing the direction of repulsion.4. At last, the paper gives the experiments, function module tests and system integration tests are included. The experiments prove that the control system is reliable and stable. The gait experiments which include three-foot gait straight walking, turning and unilateral bilateral obstacle show the designing reasonable of eccentric-type legged hexapod robot. The simulation experiments in the aspect of path planning prove that the artificial potential field model can lead the robot avoiding the obstacles smoothly.