Research on fabrics stack separation and transfer method based on Bernoulli suction cup non-contact grasping technology

Abstract

Separating fabrics stack using mechanical devices is considered a major obstacle to automation in garment processing due to their low density, low bending stiffness, and air permeability. To address this challenge, this paper discusses the feasibility of using a non-contact Bernoulli suction cup for automated separation and transfer of fabrics stack. First, a theoretical analysis of the non-contact separation mechanism was carried out and a calculation model for the separation process parameters was proposed. Subsequently, based on the calculation model, to improve the success rate of separation, a novel gradual descent separation method was proposed by analyzing the variations of suction force of Bernoulli suction cup with process parameters. To address the problem of fabric instability and falling during non-contact transfer, a visual control method that uses machine vision technology to regulate the suction force was also introduced. Finally, the above methods were integrated to create a non-contact automatic fabrics stack separation and transfer system. The results show the following: (1) The deviation between the results of the calculation model and the measured results is 6.9%; (2) The success rate of stack separation using the gradual descent method is 96%; (3) The improved visual detector achieved a recognition accuracy of 0.982 for the sagging deformation of the fabric piece. The visual control suction method can stabilize the fabric within 300 ms at a transfer speed of 800–1000 mm/s. The method for non-contact automatic separation and transfer of fabrics stack proposed in this paper provides new ideas for related research and industrial applications.