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As the core machining process element in the overall manufacturing process of a part, the machining process route plays an important role in improving final manufacturing quality. In the current CAPP system, the decision-making of the process route still depends on human-computer interaction and essentially depends on human intelligence. In the past decade, deep learning technology architecture has been gradually improved, which provides a new enabling technology for intelligent process planning. Recently, some researchers have applied deep learning to process route decision-making. However, due to the challenges of data representation and deep learning network construction, this promising solution is still at infancy. To address the two challenges, this paper presents a novel process route generation approach based on deep learning. First, we propose a fourth-order tensor model to represent the geometry and technological requirements of a part. And the relation matrix is constructed to represent the relationships among machining features. The process route is represented as a sequential set of one-hot vectors. Then, we construct an encoder-decoder neural architecture to automatically generate the machining process route for the part. The 3D convolution neuron network-based encoder converts the geometry, technological requirements, and the information of the relationships among machining features into a higher layer of vector representation, and the long short-term memory network-based decoder maps this representation to the process route. The whole neural architecture including the encoder and decoder is jointly trained to maximize the conditional probability of the target process route given the training part. Finally, the paper takes slot cavity parts as examples to verify the feasibility and effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

Defect detection is a very important link for much manufacturing and processing applications which could be used for quality control and precise maintenance decision. However, faced with the weak-texture and low-contrast industrial environment, high-precision defect detection still faces a certain challenge due to diverse and complex of defects. Meanwhile, due to a minimal portion image pixels of defects, the pixel-level defect detection task is always against class-unbalance issue which also will affect the detection performance. Recently, with the strong automatic feature representation ability, deep learning has shown an excellent detection performance on defect identification and location. Nevertheless, it still has some demerits, such as insufficient processing of feature maps, lack of temporal modeling information, etc. To address these issues, on the basis of the encoder–decoder architecture, a pixel-level deep segmentation network is proposed for automatic defect detection to construct an end-to-end defect segmentation model. To realize effective feature representation, a residual attention network is proposed to construct the backbone network, which could also make the segmentation network better emphasize target regions. Meanwhile, to improve the network propagation ability of subtle context features, a bidirectional convolutional long short-term memory (ConvLSTM) block is introduced to optimize the skip connections to learn long-range spatial contexts. Besides, a weighted loss function is proposed for model training to address the class-unbalance issue. Combined with multiple public data sets, through qualitative and quantitative analysis, experimental results demonstrate that the proposed defect segmentation network achieves a better performance compared to other state-of-the-art segmentation methods. [ABSTRACT FROM AUTHOR]

Since the outbreak of COVID-19, in order to reduce people's contact, the takeaway business has been developed rapidly, bringing a large demand for disposable and degradable tableware (e.g., wooden spoon). However, in the production process of wooden spoon, the selection of crack spoons still relies on manual labour. Therefore, in order to detect cracked wooden spoons more effectively and reduce production costs, we propose a wooden spoon crack detection method by using machine vision techniques and apply it in real-world industrial factory. In the production system, the captured color of crack regions is black while the good region shows normal log color. The positions of crack regions are located frequently in the central or marginal areas of spoons and their directions of cracks are often same due to the extrusion of the mold in the production process. Based on these two types of prior knowledge (i.e., color and spatial prior information), three modules are designed to explore these priors by jointly integrating with the current mainstream detection network of YOLO-v5, which satisfies the speed and accuracy for detecting cracks. The color fusion module is designed to explore the color difference between good regions and crack regions. The attention and orientation modules are then combined and embedded into the backbone of deep architecture. Reported experiments on our collected database show that our proposed detection method can locate the spoon cracks very well and significantly outperforms the model of YOLO-v5 with the protocols of R e c a l l , P r e c i s i o n and m e a n A v e r a g e P r e c i s i o n (m A P). • A method with prior analysis is proposed for wooden spoon crack detection. • The color and spatial priors are analyzed for inspecting cracks. • A vision-based system has been deployed and achieved promising performance. [ABSTRACT FROM AUTHOR]