An Accurate Activate Screw Detection Method for Automatic Electric Vehicle Battery Disassembly

With the increasing popularity of electric vehicles, the number of end-of-life (EOF) electric vehicle batteries (EVBs) is also increasing day by day. Efficient dismantling and recycling of EVBs are essential to ensure environmental protection. There are many types of EVBs with complex structures, and the current automatic dismantling line is immature and lacks corresponding dismantling equipment. This makes it difficult for some small parts to be disassembled precisely. Screws are used extensively in batteries to fix or connect modules in EVBs. However, due to the small size of screws and differences in installation angles, screw detection is a very challenging task and a significant obstacle to automatic EVBs disassembly. This research proposes a systematic method to complete screw detection called "Active Screw Detection". The experimental results show that with the YOLOX-s model, the improved YOLOX model achieves 95.92% and 92.14% accuracy for both mAP(50) and mAP(75) positioning after autonomous adjustment of the robotic arm attitude. Compared to the method without autonomous adjustment of the robotic arm, mAP(50) and mAP(75) improved by 62.81% and 57.67%, respectively. In addition, the improved YOLOX model improves mAP(50 )and mAP(75) by 0.19% and 3.59%, respectively, compared to the original YOLOX model.