Hexapod robot kinematics modeling and tripod gait design based on the foot end trajectory

Hexapod robots have strong crawling abilities and complex gaits. Referring the configuration of ants, a hexapod robot is designed. Based on the DH parameters and the homogeneous transformation matrix, the direct and inverse kinematic models are built, and the workspace of the foot end is analyzed. For the tripod gait, the relationship between the rotation angle of the leg with respect to body and the foot movement is built. The foot end trajectories of the swing phase are designed by adopting sine and cosine functions, the stance phase by horizontal straight line function. The angle joint trajectories are obtained by evaluating the inverse kinematic equations. Finally, the tripod gaits, including straight, transvers and swivel gaits, are designed. The experimental results illustrate the effectiveness of the robot gait planning algorithms. The design method in this paper is easy to understand and calculate.