机械手采摘黄瓜的振动特性试验

Test on vibration characteristics of cucumber picked by harvesting manipulator

为研究黄瓜在被采摘时的振动特性，减少采摘机械手对黄瓜造成的振动损伤，选择中国普遍种植的华北型剌黄瓜，模拟采摘机械手抓握黄瓜的姿态进行黄瓜弯曲振动试验，得到不同外形黄瓜的共振频率和振动变形量的试验数据。分析了试验参数之间的相关性，拟合了黄瓜的受力与变形之间的对应关系曲线。结果表明，以1～1000Hz的频率范围对模拟弹性机械手爪采摘的状态的新鲜黄瓜激振，能检测到二阶共振频率，且两阶共振频率之间显著相关。黄瓜体长与二阶共振频率皆呈显著负相关；瓜柄长与第一阶共振频率呈显著负相关；而黄瓜质量与第二阶共振频率呈显著负相关。黄瓜的弯曲变形表现出明显的非线性特性。

In order to study the vibration characteristics of cucumber to be picked and reduce the vibration injury of cucumber caused by harvesting manipulator, the North China bur cucumber breed planted universally in China selected, to conduct the bending vibration test for simulating the gesture that harvesting manipulator grasps cucumber. The trial data of the resonance frequencies and vibrating deformations of cucumbers different from shape and mass were obtained. The correlations of the trial parameters were analyzed and the corresponding relationship curves of cucumber received power and its deformations were regressed. The result shows that, stimulating the flexible manipulator holding cucumber at the range of 1～1000 Hz frequency, two resonance frequencies can be tested, and they are remarkably correlatd. Cucumber length has remarkably negative correlation with two syntonic frequencies; cucumber peduncle length has remarkably negative correlation with the first syntonic frequency; but the fruit weight has remarkably negative correlation with its second syntonic frequency. The bending vibration deformation of cucumber appears obvious non-linear characteristics.