航天员舱外操作载荷分析的逆运动学建模方法

Extravehicular Operating Load Analysis Using Inverse Kinematic Astronaut Modeling Method

针对航天员舱外活动中操作动作对扶手和脚限制器约束点造成的载荷进行精细化分析。对失重环境下航天员的运动特点进行了总结,采用逆运动学算法对航天员上肢操作动作进行建模;引入运动耗能、关节角与施力能力的关系、航天服活动反力矩等条件作为冗余系统约束;并考虑身高、体重、工作位点距离等精细化因素对操作载荷的影响。对沿扶手行走和搬运大质量物体典型算例的分析表明,此方法利用最小耗能准则进行出舱活动复杂运动的逆运动学求解具有可行性,基于本方法分析模型精细化参数影响,分析了操作力和力矩载荷与航天员体重、身高和工作位点距离的关系,并可据此开展更加精确的出舱活动操作载荷预测,为有关结构设计提供参考。

A fine-grained analysis is conducted on the loads caused by the constraints on handrails and foot restraints during extravehicular activities(EVAs)of Chinese astronauts.The movement characteristics of astronauts in a weightless environment are summarized,and an inverse kinematics algorithm is used to model upper limb operations.Conditions such as motion energy consumption,relations between joint force outputting capability and joint angle,and reactive torque of the spacesuit are considered as redundant system constraints.Factors such as height,weight,and operating position of astronauts are considered to analyze the impact on the solution the magnitude of applied loads.Through the analysis of examples involving spacewalk along handrails and move heavy objects,the proposed method demonstrate feasibility in solving complex inverse kinematics problems for EVAs based on the criterion of minimum energy consumption.Based on the analysis of fine-grained parameters,the relations between the operating loads on the constraint points and astronaut mass,height or handle distance are analyzed,which could provide practicability toward a more accurate operating load analysis for spacecraft structure design.