Q15-based flat knitting machine′s needle position tracking algorithm

Having analyzed the two tracking methods of needle position of flat knitting machine,a new algorithm principle of needle position tracking of flat knitting machine is proposed,which is based on quadrature encoding signals feeding back from AC servo motor.The algorithm,based on Q15,is successfully applied to convert floating-point into fixed-point.The Q value is determined by statistical analysis.The real-time simulation and comparison of hardware is performed on the platform of the flat knitting machine.The results indicate that the time consumption completing once computation of needle position tracking with Q15 is 141.05 ns,and computing efficiency increased by 65.43% as compared with the conventional algorithm.This algorithm can be applied to needle position tracking of other knitting machines,such as socks knitting machine,circular knitting machine,underwear machine,etc.