工业装配抗振外骨骼上肢减振性能研究

A study on vibration reduction performance of the upper extremity of industrial assembly anti-vibration exoskeleton

操作动力工具存在巨大的危害性,动力工具产生的持续性或间歇性振动传递到手掌和手臂,对工人的肌肉骨骼系统的损伤不可忽视。为降低装配工人暴露于振动环境下的风险,提出一种上肢具有斜弹簧阻尼防振结构的抗振外骨骼。对该外骨骼上肢数学建模,利用谐波平衡法得到其幅频方程和力传递率T f表达式。以力传递率和固有频率作为减振性能评价指标,设计多组不同的弹簧刚度k 1,k 2、阻尼系数c 1,c 2、连杆长度比l 1/l 2,分析各结构参数对减振性能的影响。结果表明:k 1,k 2、c 1,c 2、l 1/l 2均对减振性能有显著影响,并且k 2、c 2的影响程度高于k 1、c 1。当工具振动频率低于上肢固有频率时,增大k 1,k 2能有效降低力传递率,增大减振性能,反之;增大c 1,c 2能够有效降低力传递率,提高系统的减振性能;l 1/l 2=1.0时,力传递率最低,具有更好的减振效果。

Operating power tools is potentially harmful.Continuous or intermittent vibration generated by a power tool is transmitted to a palm and a arm,causing damage to the worker's musculoskeletal system.In order to reduce the risk of assembly workers exposed to vibration,this work proposes an anti-vibration exoskeleton with inclined spring-damped upper extremity.The upper extremity of the exoskeleton was mathematically modeled and the amplitude frequency equation and the force transmissibility T f were obtained by a harmonic balance method.Taking the force transmissibility and natural frequency as the evaluation indexes of the vibration reduction performance,tests with different spring stiffness k 1,k 2,damping coefficient c 1,c 2 and connecting rod length ratio l 1/l 2 were designed to analyze the influence of various structural parameters on the vibration reduction performance.The result of the tests shows that k 1,k 2、c 1,c 2 and l 1/l 2 all have significant influence on vibration reduction performance,and the influence of k 2,c 2 is higher than that of k 1,c 1.When the vibration frequency of the tool is lower than the natural frequency of the upper extremity,increasing k 1,k 2 can effectively reduce force transmissibility and increase vibration reduction performance,and vice versa.Increasing c 1,c 2 can effectively reduce force transmissibility and improve vibration reduction performance.When l 1/l 2=1.0,the force transmissibility is the lowest,with better vibration reduction effect.