下肢外骨骼机器人大腿板模态分析与拓扑优化

为提高下肢外骨骼机器人的性能,需对下肢外骨骼机器人部分零件进行结构优化。针对下肢外骨骼机器人大腿板,利用拓扑优化方法,将零件的模态数据作为优化依据。首先建立零件的三维模型,将其导入到Workbench软件中进行静力学分析和模态分析,得到大腿板在最大工作载荷处的最大应力和最大应变以及大腿板前4阶固有频率和最大振幅。然后进行开槽处理,将槽宽设为变量,求解出不同槽宽下的模态参数。最后根据固有频率和振幅参数,在满足减重需求和零件强度需求的情况下,选定槽宽的最优值。经开槽处理后大腿板质量减少明显,固有频率有所减小,抗振性能有所下降,但依然能够满足工况需求,且零件的静力学分析也能够满足要求,故验证了拓扑优化的可行性,对下肢外骨骼机器人结构优化具有参考价值。

Modal Analysis and Topology Optimization of Thigh Plate for Lower Extremity Exoskeleton Robot

In order to improve the performance of the lower extremity exoskeleton robot,structural optimization for parts of the lower extremity exoskeleton robot is required.The modal data of the part were used as the optimization basis for the thigh board by using the topology optimization method.Firstly,the 3 D model of the part was built and imported into the Workbench software for static analysis and modal analysis.The maximum stress and maximum strain of the thigh plate at the maximum working load and the natural frequency and maximum amplitude of the first 4 orders of the thigh plate were obtained.Then,the grooving process was performed,and the groove width was set as a variable to solve the modal parameters under different groove widths.Finally,according to the natural frequency and amplitude parameters,the optimal value of the groove width was selected in the case of meeting the weight reduction requirement and the part strength requirement.After the slotting treatment,the weight of the thigh plate is obviously reduced,the natural frequency is decreased,the anti-vibration performance is reduced,but the working condition can still be met,and the static analysis of the part can also meet the requirements,so the topology optimization is verified.It has certain reference value for structural optimization of lower extremity exoskeleton robot.