末端执行器切割机构的有限元分析及优化设计

Finite element analysis and optimization design of end-effector cutting mechanism

为验证末端执行器切割机构设计的合理性,以减重为目的进行优化设计,根据实际工况,对切割机构进行了有限元分析。以减重为目的,将扇形齿轮更换为密度较小的尼龙件,并对其结构进行了拓扑优化设计。结果显示:优化后比优化前的扇形齿轮质量减小87.6%,切割机构的质量减小50.4%;优化后扇形齿轮的最大应力为27.5 MPa(小于屈服应力),应变为0.013 mm(能满足使用要求);优化设计使切割机构的前4阶固有频率都显著提高,且第一阶固有频率提高了155%,大于振动频率;优化设计的切割机构在正常使用中不会产生共振,优化效果显著。切割机构的有限元分析和优化设计,为苹果采摘机器人的研究提供了理论参考和依据。

In order to verify the rationality of the cutting mechanism design of the end effector, and optimize the design with the goal of weight reduction. According to the actual working conditions, the statics analysis of the main parts and the modal analysis of the cutting mechanism were carried out. In order to reduce weight, the sector gear is replaced with nylon with low density, and then its structure is optimized by topology optimization. The results show that after optimization, the weight of the sector gear decreased by 87.6%, the total weight of the cutting mechanism decreased by 50.4%, the maximum stress of the sector gear is 27.5 MPa less than the yield stress, and the strain is 0.013 mm, which meets the requirements. The first four natural frequencies of the cutting mechanism are significantly increased, and the first natural frequency is increased by 155%, which is greater than the vibration frequency, will not produce resonance. The effect of optimization is remarkable. The finite element analysis and optimization of the cutting mechanism of the end effector provide a theoretical reference and basis for the future research of apple and other fruit picking mechanisms.