双足机器人步态规划与性能分析研究

发布时间：2018-03-05 16:17

本文选题：双足机器人　切入点：步态规划　出处：《昆明理工大学》2017年硕士论文　论文类型：学位论文

【摘要】：双足机器人是机器人领域的一个研究热点和重要的研究方向,它相对于其他移动机器人具有人类步行的特征和更高的灵活性。其中最佳步行策略已成为研究的热点,步态规划是实现稳定步行策略的基础和关键。本文基于倒立摆模型进行了步态规划并且以设计的稳定性函数和能耗性函数为衡量标准以步行一定范围速度和摩擦系数为变量寻找此范围内的最佳步行策略。本文以实验室物理样机为原型建立双足机器人的运动学模型,根据双足机器人自身特点将双足机器人简化为一级倒立摆模型进行步态规划。并通过逆向运动学的相关理论计算出机器人各个关节的运动轨迹。设计了虚拟样机中评价稳定性和能耗性的可行评价函数。为仿真模型在不同工况下的步行策略的稳定性能和能耗性的比较提供了理论依据。在ADAMS运动学仿真的情况下根据设计的评判稳定性能指标的公式计算不同步行速度及机器人与地面不同摩擦系数下的稳定性能参数,并采用单因素分析法步行速度、与地面摩擦系数因素对步行稳定性影响规律。得出结论:不同速度都有保持机器人稳定性需要的最低摩擦系数,低于摩擦系数最低要求,机器人稳定性降低速率加快,相同摩擦系数即使在满足稳定行走最低要求情况下,当机器人高于某个速度,稳定性能也会加速下降,得出本文研究机器人在一定步行速度范围及与地面擦系数范围最佳行走速度200mm/s需要的摩擦系数0.6及以上。并设计稳定性实验验证了设计函数的合理性及仿真结果的有效性。基于ADAMS与MATLAB联合仿真下得到机器人在步行过程中各个关节的力矩变化曲线与关节角速度等后处理结果,并且基于不同工况下对后处理结果提取出的各部位关节力矩与关节角速度进行拟合,根据设计的能耗函数计算出不同速度与摩擦系数下的能耗。采用单因素法,分析不同步行速度、与地面不同摩擦系数等因素对双足机器人步行能耗的影响。同时结合前边稳定性分析得出,机器人相同速度下,当没有达到稳定需要的最低摩擦系数情况下,摩擦系数降低能耗增加,当达到一定摩擦系数以上,不同摩擦系数基本保持一致,当达到稳定性需要的最低标准,速度超过某一速度能耗增加速率变快。同时根据本文研究的步行速度(50mm/s-250mm/s)和与地面摩擦系数(0.3-0.7)范围内,得出步行速度200 mm/s时摩擦系数0.6以上,是在机器人保持能耗增速变化不大情况下所能达到最高速度,所以本机器人从工作的高效性考虑,结合前边的稳定性总结出本机器人保持一定稳定性前提尽力提高工作效率下所能达到最佳的步行工作速度为200mm/s。并设计能耗性实验验证了设计函数的合理性及仿真结果的有效性。
[Abstract]:Biped robot is a hotspot and an important research direction in the field of robot. Compared with other mobile robots, biped robot has the characteristics of human walking and higher flexibility, among which the best walking strategy has become a hot topic. Gait planning is the foundation and key to realize the stable walking strategy. This paper presents gait planning based on inverted pendulum model and takes the designed stability function and energy consumption function as the criterion to measure the walking speed and friction in a certain range. The coefficient is variable to find the best walking strategy in this range. In this paper, the kinematics model of biped robot is established based on the prototype of laboratory physics. According to the characteristics of biped robot, the biped robot is simplified into a single inverted pendulum model for gait planning, and the trajectory of each joint of the robot is calculated by the theory of inverse kinematics. A virtual prototype is designed. It provides a theoretical basis for the comparison of the stability and energy consumption of the simulation model under different operating conditions. Based on the results of ADAMS kinematics simulation, The formulas for evaluating the stability performance index are used to calculate the stability performance parameters under different walking speeds and different friction coefficients between the robot and the ground. The single factor analysis method is used to analyze the walking speed, and the friction coefficient between the ground and the ground affects the walking stability. It is concluded that all the different speeds have the lowest friction coefficient needed to maintain the stability of the robot, which is lower than the minimum requirement of the friction coefficient. The stability reduction rate of the robot is accelerated. Even if the same friction coefficient meets the minimum requirement of stable walking, the stability performance of the robot will decrease more quickly when the robot is higher than a certain speed. In this paper, the friction coefficient of the robot in a certain walking speed range and the optimum walking speed of 200mm / s with the ground erasure coefficient is obtained. The design stability experiment verifies the rationality of the design function and the simulation results. Based on the joint simulation of ADAMS and MATLAB, the post-processing results such as torque variation curve and joint angular velocity of each joint in the walking process of the robot are obtained. Based on different working conditions, the joint torque and joint angular velocity extracted from the post-processing results are fitted, and the energy consumption under different velocity and friction coefficient is calculated according to the designed energy consumption function. The single factor method is used. The effects of different walking speed and friction coefficient on walking energy consumption of biped robot are analyzed. When the minimum friction coefficient of stability is not reached, the friction coefficient decreases and the energy consumption increases. When the friction coefficient is above a certain coefficient, the different friction coefficients are basically the same, and when the minimum standard of stability is reached, According to the walking speed of 50 mm / s -250 mm / s and the friction coefficient of 0.3-0.7), the friction coefficient of the walking speed of 200 mm/s is more than 0.6. The robot is able to achieve the highest speed in the case of little change in the rate of increase in energy consumption, so the robot takes into account the efficiency of its work. Combined with the stability of the front, it is concluded that the optimal walking speed of the robot is 200 mm / s under the condition of keeping a certain stability and trying to improve the working efficiency. The design of energy consumption experiment verifies the rationality of the design function and the validity of the simulation results.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP242

【参考文献】