Automated Straight-Line Sewing of Stretchable Fabrics with Different Lengths
Bingchen Jin, Akinari Kobayashi, Dipankar Bhattacharya, Akira Seino, Fuyuki Tokuda, Norman Tien, Kazuhiro Kosuge
AI summary
Problem
Automating Different Length Alignment Sewing (DLAS) remains challenging because existing systems rely on restrictive fixtures, cannot independently control multiple fabric layers, assume pre-grasped materials, or fail to prevent fabric slippage during stretching.
Approach
The authors introduce DLRoSS, a fixture-free robotic system that uses a novel roller-based end-effector with active feed rollers and a passive press roller. It automates the sewing process in four phases, using real-time velocity control to stretch the shorter fabric to match the longer one during stitching.
Key results
- First robotic system to automatically stretch and sew two fabrics of different lengths without fixtures
- Novel roller-based end-effector with a passive press roller prevents fabric slippage during stretching
- Real-time fabric feeding speed sensing system ensures precise synchronization with the sewing machine
- Experimental validation demonstrates consistent, high-quality straight-line sewing across different stretchable fabrics and length ratios
Why it matters
Automating DLAS reduces labor and cost in garment manufacturing, enabling efficient production of complex garments like elastic bands on shirts and jackets.
Abstract
Different Length Alignment Sewing (DLAS), which involves stretching the shorter fabric to match the longer one and sewing them together in a straight line, is a challenging task that needs to satisfy several requirements when automating the sewing process. To address the challenges, this research proposes a novel robotic sewing system, Different Length Robotic Sewing System (DLRoSS), which consists of a roller type end-effector, attached to a 6-DoF manipulator. The end-effector composed of active shorter and longer fabric rollers, and a passive press-roller attached to the shorter-fabric roller. Assuming that one end of the two fabric layers are initially positioned under the sewing machine’s presser foot, the system automates DLAS by operating in four distinct phases. (P1) Fabric wrapping: Individual fabric layers are picked, held, and wrapped from the other end onto the feed rollers. (P2) Sewing: During the sewing, the shorter fabric is stretched and aligned with the longer fabric in real-time using roller velocity control based on the sewing speed and apriori known length ratio. (P3) Sewing completion: In the final sewing round on the fabric rollers, the press roller is engaged to prevent the stretched fabric from slipping off due to internal tension. (P4) Sewing fabric release: At the end of sewing, the fabric edge moves past the press roller, and the fabric releases from the rollers. Experimental results demonstrate that DLRoSS achieves consistent, high-quality sewing of stretchable fabrics of different materials and lengths.