The existing hexapod robots have shortcomings in single foot structure design, body layout and compliant motion control, resulting in weak terrain adaptability and low motion compliant performance. Therefore, observation experiment was conducted on a typical hexapod organism-ant. Based on the analysis of the physiological structure characteristic and driving mode of ant, basic principles applicable to the structure design of hexapod robot were proposed; based on the design of a low inertia single foot structure, an overall biomimetic structure of a hexapod robot driven by joint motors was proposed by optimizing the body layout of the robot; based on the gait of the straight and turning movements of the hexapod robot, a foot end trajectory combining trigonometric function curve and straight line was planned, and a compliant motion control method for the hexapod robot based on hierarchical control was proposed. The prototype experimental results showed that the hexapod robot had a reasonable structure design and could achieve relatively compliant straight and turning movements. The research results can provide important references for the design of robot biomimetic structure and compliant motion control.

Keywords： hexapod robot ; biomimetic structure design ; compliant motion control ; biological observation experiment ; joint motor drive