并联式髋关节摩擦特性试验机驱动机构运动学研究

为了克服现有髋关节试验机在复杂运动轨迹模拟和变载荷动力加载等方面存在的不足,试制了一台以3SPS+1PS并联机构为核心驱动模块的髋关节试验机。基于Rodrigues参数,对该髋关节试验机的驱动机构进行了运动学建模和求解。根据ISO14242-1:2002(E)标准的相关规定,对该机构逆运动学模型进行了数值仿真,得到模拟髋关节运动所需的主动件运动学参数变化规律,确定了该髋关节试验机的运动方案,并验证了驱动件选型的合理性。通过耗时计算,测得Rodrigues参数法求解试验机逆运动学的运算时间,满足控制实时性的需要。

Kinematics Study of a Driving Mechanism of a Parallel Hip Joint Simulator

In order to overcome defects in complex motion simulation and variable dynamic loading of hip joint simulators available in literature,a parallel hip joint simulator with a 3SPS+1PS parallel manipulator as core module is proposed.Its kinematic model was established and then solved based on Rodrigues parameters.According to ISO14242-1:2002(E) standard,a numerical simulation of the inverse kinematics was conducted.Then,variation laws of kinematic parameters of the driving legs were obtained.Meanwhile,motion scheme of the simulator was determined and selection of actuators was validated.Finally,the time consumption of the inverse kinematics calculation based on Rodrigues parameters was recorded which can meet the real-time demand.