Xialiang Ye and Minbo Li
Press-fit with force and displacement monitoring is commonly adopted in automotive mechatronic system assembling. However, suitable methods for the press-fit study are still at…
Abstract
Purpose
Press-fit with force and displacement monitoring is commonly adopted in automotive mechatronic system assembling. However, suitable methods for the press-fit study are still at initial investigation phase. The sequential data physical meaning, small data sets from different resources and computing efficiency should be considered. Therefore, this paper aims to better identify press-fit fault types.
Design/methodology/approach
This paper proposed one-dimensional convolutional neural network (1DCNN)–long short-term memory (LSTM) method to perform press-fit fault diagnosis into automotive assembling practice which is in accordance with current product development procedure. Specialized data augmentation method is proposed to merge different data resources and increase the sample size. Referring one-way sequential data characteristics, LSTM and batch normalization layers are integrated in 1DCNN to improve the performance.
Findings
The proposed 1DCNN-LSTM method is feasible with small data sets from different sources. Using data augmentation to make data unified and sample size increased, the accuracy could reach more than 99%. Training time has reduced from 90 s/Epoch to 4 s/Epoch compare to pure LSTM method.
Originality/value
The proposed method shows better performance with less training time compared to LSTM. Therefore, the method has practical value and is worthy of industrial application.
Details
Keywords
Yinhua Liu, Xialiang Ye, Feixiang Ji and Sun Jin
– This paper aims to provide a new dynamic modeling approach for root cause detection of the auto-body assembly variation.
Abstract
Purpose
This paper aims to provide a new dynamic modeling approach for root cause detection of the auto-body assembly variation.
Design/methodology/approach
The dynamic characteristics, such as fixture element wear and quality of incoming parts, are considered in assembly variation modeling with the dynamic Bayesian network. Based on the network structure mapping, the parameter learning of different types of nodes is conducted by integrating process knowledge and Monte Carlo simulation. The inference was that both the measurement data and maintenance actions are evidence for the improvement of diagnosis accuracy.
Findings
The proposed assembly variation model which has incorporated dynamic manufacturing features could be used to detect multiple process faults effectively.
Originality/value
A dynamic variation modeling method is proposed. This method could be used to provide more accurate diagnosis results and preventive maintenance guidelines for the assembly process.