精确地描述和分析系统动力学特性一直是仿人机器人研究方向需要解决的关键课题之一，而至今为止，针对此系统的已有建模理论和方法一般是以其结构刚性杆件简化，以及将杆件以单纯铰链联结成“骨架”为前提，建立在传统多刚体动力学理论基础上，这些研究成果由于结构的简化和多刚体理论的局限，只能近似地反映仿人机器人系统的步行动力学特性。　　但是，随着逐渐提高的行走性能要求，需要考虑仿人机器人的本质粘弹性力学性质和复杂非线性结构特征，以更完整和精确地描述其行走动力学性能。　　因此，为解决复杂的仿人机器人系统动力学建模和分析问题，论文针对清华大学研制的第一代仿人双足步行机器人——THBIP-Ⅰ系统，考虑具体三维结构及其材质本质粘弹特性，如结构柔性和关节弹性等方面的影响，运用三维有限元理论和ANSYS软件技术，系统和深入地研究了其动力学特性的有限元建模技术与方法，以及具体行走动力学特性的分析问题。　　论文首先研究建立了THBIP-Ⅰ仿人机器人系统的精确弹性动力学有限元分析模型，并在此基础上进行结构静力学分析，研究各部件应力、应变分布状况，分析其强度和刚性等力学性能，提出THBIP-Ⅰ结构优化初步措施，为结构优化设计提供理论依据。　　其次，运用模态分析理论和ANSYS中模态分析软件，进行THBIP-Ⅰ模态分析，研究支撑转换期THBIP-Ⅰ各阶模态及其振动特性（固有频率和振型），并结合实验现象，对样机结构的振动特性趋势进行了初步的研究。　　最后论文应用所建立的有限元弹性动力学模型，考虑结构柔性和关节弹性等结构特性的影响，进行THBIP-Ⅰ步态设计优化和步行稳定性研究，并从加阻尼介质、改变提腿和落腿速度、以及提腿和落腿时脚掌姿态等措施入手，进行THBIP-Ⅰ仿人步行支撑转换期的冲击振动有限元分析研究。

　　Characterizing and analyzing the dynamic properties of the humanoid-robot is one of the key problems in the research field of robot. But at present, the existing mo- deling methods of the humanoid-robot dynamics are based on the theory of traditional multi-rigid-body dynamics, and usually simplifying the system as framework with multi-rigidity poles and simplex joints. For this reason, the walking dynamic performance of the humanoid-robot is pictured only approximately by these methods.　　With the advancing demands of the walking capability for the humanoid-robot, its viscoelastic and complex nonlinear structure properties must be considered to present more perfectly and precisely the walking dynamic performance.　　In order to solve over dynamics modeling and analyzing problems of the humanoid-robot with the viscoelastic and nonlinear structure properties, this dissertation studys to build the dynamic model and analyze its walking property of the THBIP-Ⅰ humanoid-robot, who has been developed by Tsinghua University, by the three-dimension finite element analysis (FEA) method in the ANSYS platform.　　Firstly, this paper presents a precise viscoelastic dynamics FEA model of the THBIP-I. And being based on the FEA model, the distribution of strain and stress on the system are computed to analyze its structure intensity and rigidity properties. The research of the structure-statics gives out some rules to direct the design optimization of the THBIP-I.　　Secondly, using the theory of modal analysis and the ANSYS modal analysis software, the modes and the vibratility of the THBIP-Ⅰ, such as the inherent frequen- cies and the vibration modalities, are studied during its single-double support switch time, and more, combining with the experimental phenomenon, the developing trends of the real vibration properties of the THBIP-Ⅰare also discussed.　　Lastly, being base on the FEA model of THBIP-Ⅰ, and considering the effect of the structure-flexibility and joints-elasticity, the paper investigates the gait-design optimization and walking stability. In addition, by adding damp medium, or changing the velocity and the foot gesture of raising and falling legs, the impact vibratility of the THBIP-Ⅰ during its single-double support switch time is also worked over with the FEA method in the ANSYS.