Driving System Design and Two-Dimension Bar Tacking Function Control of an Industrial Sewing Machine

• Main Authors: Chi-Hsiang Li, 李啟祥
• Other Authors: Ching-Chih Tsai
• Format: Others
• Language: en_US
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/36629207815490844786

碩士 === 國立中興大學 === 電機工程學系所 === 105 === This thesis presents techniques for driving system design and 2D bar-tacking function control of an industrial sewing machine which is driven by one brushless direct-current (BLDC) spindle motor and four stepping motors and related sewing mechanisms. The BLDC spindle motor is controlled to drive the main shaft of the sewing machine which connects forward to the mechanisms of the needle bar above the sewing platform and the bobbin under it. This may make the upper thread in the top of the needle go down and hook up the under thread in the bobbin, and then go up and form a lockstitch in the fabric to achieve desired stitching. Moreover, two of the four stepping motors are employed to move the X-Y table and stitched fabrics and the remaining two stepping motors are respectively used for thread trimming and presser foot lifting. The 2-DOF (two-degrees-of-freedom) digital PID control methods are utilized to accomplish robust and precise velocity tracking against load changes and parameter variations. The collaborative control policy of the BLDC spindle motor and the two stepping motors in the X-Y table are proposed to achieve the function of sewing two-dimensional patterns. With the aforementioned firmware, the proposed bar tacking control system is constructed to stitch many bar, semi lunar and radial sewing patterns. Experimental results are conducted to show the effectiveness, merits and applicability of the proposed control system.