Abstract: In order to solve the problem of bipedal walking, an improved method of gait planning algorithm of
biped robot based on L3D-LIPM(Linear Inverted Pendulum Mode) is proposed. This method obtains the COM
trajectory of robot by simplifying the original 3D linear inverted pendulum. After planning the swing leg
trajectory, the sequence of each joint can be obtained by inverse kinematics of the robot. The algorithm adopts
dynamically adjusting the point in time at which the support foot alternates to maximize the possible range in
single support phase, instead of a short double support phase for accelerating or decelerating the center of mass to
achieve such an adjustment. Experimental results demonstrate the feasibility and effectiveness of the approach.

Key words:  biped robot, gait planning, center of mass (COM) balance, 3D linear inverted pendulum, reference trajectory