The Development Of The Electronic Let-off And Take-up Control System Of The Rapier Loom Based On DSP

At present, the rapier looms are widely used as the shuttle-less looms because oftheir strong adaptability. Electronic let off (ELO) system and electronic take up (ETU)system are the main parts of the loom control system. The control precision of the yarntension and the weft density has the consanguineous relation to prime performance of theloom control system. So it is the most important target of loom control quality. ELO andETU are the important symbols of the slap-up looms. So it is very essential to advanceand improve the control system performance of ELO and ETU of the rapier looms.Consequently, the ELO and ETU control systems based on AC servo technology andDSP(digital signal processor) are put forward. The primary tasks are as follows:Firstly, the development of the ELO and the ETU system at home and abroad, andthe principle and characteristics of the system are analyzed. Based on these research, thecontrol scheme of the system is presented.Secondly, the hardware of the ELO and the ETU control system based on the DSPmoulding board and AC servo system is designed and the scheme of the hardwarestructure is given.Thirdly, the software of the ELO and the ETU control system based on the DSPmoulding board and AC servo system is opened up. The constant tension control of ELOcan be realized and eight kind of tension can be set ahead of time. The precise control ofELO is realized. The weft density can be changed on line and eight kinds of tension canbe set ahead of schedule through man-machine conversation. At the same time the state ofthe loom can be watched. Besides the function of stop-bridge cooperating the function ofchanging the weft density on line is added to system. So the special technicalrequirements of the complex design can be sufficed.Fourthly, the hardware of the system adopts anti-jamming measures such as shieldand isolation between ray and electricity while the software takes measures such aswatchdog and redundant instruction. So the reliability of the system is well guaranteed.Fifthly, the tension compensation and the weft density compensation as two appliedsolutions are presented aiming at the problem of start mark. So it is well improved.Through long-term spot debugging, the system runs stable and has good controlperformance. It achieves the goal of the design and realizes the prospective effect.