针对实际工程中工业机器人末端抖动程度难以通过简单指标进行有效区分,且识别过程存在外部干扰大、抖动位置分布不均的问题,提出了变初位数据增强和深度特征提取的工业机器人末端抖动状态识别方法。首先,利用陷波滤波器滤除工业机器人末端振动信号中的工频干扰,并通过均方根阈值搜索抖动位置及改变搜索初始位置数据增强的方式,获取充足且能展现工业机器人运动状态的末端抖动数据;其次,采用连续小波变换对末端抖动数据进行分解以获得可充分保留末端抖动冲击与震荡特征的时频图;最后,为缓解特征降维及工况变化的影响,运用去除池化层和添加批归一化的卷积神经网络,对时频图进行深度特征提取和分类,从而实现工业机器人末端抖动状态识别。实验结果表明,所提方法在不同传感器采集方向识别准确率均达到90%以上,证明了该方法能够有效识别工业机器人末端抖动状态,并具有较好的泛化性和稳定性。
Abstract
For the actual engineering industrial robot end-jitter degree is difficult to be effectively distinguished by simple indicators, and the recognition process exists large external interference and uneven distribution of jitter position problems, an industrial robot end-jitter state recognition method with variable initial position data augmentation and deep feature extraction is proposed. Firstly, power-line interference filtering in industrial robot end vibration signals using trap filters, and by means of root mean square threshold search jitter location and changing the search initial position data enhancement, to obtain sufficient end-jitter data that can show the motion state of the industrial robot; Secondly, the end-jitter data is decomposed by continuous wavelet transform to obtain the time-frequency map that can fully retain the end jitter shock and vibration characteristics; Finally, to mitigate the effects of feature downscaling and work condition variation, a convolutional neural network with the pooling layer removed and batch normalization added is applied to perform deep feature extraction and classification of the time-frequency map, which enables industrial robot end-jitter state recognition. The experimental results show that the proposed method achieves an accuracy of more than 90% in different sensor acquisition directions, which proves that the method can effectively recognition the end jitter state of industrial robots and has good generalization and stability.
关键词
工业机器人 /
抖动状态识别 /
数据增强 /
连续小波变换 /
卷积神经网络
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Key words
industrial robot /
jitter state recognition /
data augmentation /
continuous wavelet transform /
convolutional neural network
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