| Humanoid biped robot has the shape of human and also the same activities like human, they can work in people’s real environment, and can use the tools which are designed for human. The research and development about it represents the top level of the robot research. It combines multi-disciplinary-cross application, which represents a country’s highest achievement in the field of robot. Stable walking and gait generation are the foundation of multi-task of humanoid biped robots. They are also the difficulty and hotspot in the research of the humanoid robot. This dissertation does the work which aims to join in the robot challenge game hold by United States DARPA, and the work is based on the issue of summarizing the research results at home and abroad. This dissertation mainly focuses on the stable gait planning and control method for humanoid robot on multi-terrain. In this dissertation, the main research contents and innovation points in the following aspects:1. A gait generation method based on the hip height and attitude compensation using three-centroid model, now the movement mode of humanoid robot in walking speed, gait, flexibility and energy consumption can’t compare with the human natural gait. Using the human body as the reference, utilizing the Vicon Nexus motion capture system structures the natural walking motion research platform. Though capturing the human body’s joints motion trajectories and extracting the characteristic data of human walking, a gait generation method based on the hip height and attitude compensation using three-centroid model was proposed for humanoid robot. This method can effectively solve the problem of inaccurate elemental-centroid model. The XT robot walking experiments on carpet proves the effectiveness and robustness of the method.2. The consecutive stepping over problem is proposed in this dissertation, firstly, the dissertation defines two consecutive stepping over conditions, sparse stepping over (SSO) and tight stepping over (TSO). Then a novel feasibility analysis method with condition (SSO/TSO) decision criterion is proposed for consecutive obstacles stepping over. The feasibility analysis method’s output is walking parameters with obstacles’ information. Furthermore, a modified legs trajectory planning method with CoM trajectory compensation using upper body motion is proposed. Finally, simulations and experiments for SSO and TSO are carried out by using the XT humanoid robot platform with the aim to verify the validity and feasibility of the novel methods proposed in this dissertation.3. A generic walking pattern generation method for humanoid robot walking on slopes is proposed. Walking on inclined ground is an important ability for humanoid robots. In general, conventional strategies for walking on slopes lack technical analysis in, firstly, the waist posture with respect to actual robot, and secondly, the landing impact, which weakens the walking stability. In this dissertation, a generic method for walking pattern generation considering these issues is proposed with the aim of enabling humanoid robot to walk dynamically on a slope. Firstly, a virtual ground method (VGM) is proposed to give a continuous and intuitive zero-moment point (ZMP) on slopes. Then, the dynamic motion equations are derived based on 2D and 3D models respectively by using VGM. Furthermore, the waist posture with respect to the actual robot is analyzed. Finally, a reformative linear inverted pendulum (LIP) named the asymmetric linear inverted pendulum (ALIP) is proposed in order to achieve stable and dynamical walking in any direction on a slope with lower landing impact. Simulations and experiments are carried out using the XT humanoid robot platform with the aim of verifying the validity and feasibility of these new methods. ALIP with consideration of waist posture is practical in extending the ability of walking on slopes for humanoid robots.4. The two levels humanoid robot stable walking controller, the stabilizer is composed of two levels of stabilizer, the former stabilizer containing joint torque controller, the ground controller and the ZMP compensation controller, its main function is to make robots’ current ZMP move to target ZMP, decrease the distance between these two points; the latter stabilizer consists of the upper part of the body control and landing position revision control; its main function is that if the ZMP and the robot target one under the condition of the ZMP point almost overlap and there is still a falling trend (upper body tilted too large) at the same time, the upper body accelerates through breaking type adjustment then re-planning the target ZMP again to restore the robot posture and correct the landing position of swinging leg. Two level of walking stability controller ensures the stable walk for humanoid robot as described before.
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