For some years now the fabrics feeding system of an industrial overlock sewing machine has
been studied at the University of Minho, gathering different background researchers at the
Laboratory of Process Research. Following the findings reported in previous stages, briefly
summarised in this paper, a new research programme was established to enable a PC-based
open and closed-loop control of the presser foot system. This paper highlights all this recent
developments, presenting and discussing, in detail, the PID closed-loop control strategy
implemented. The results show that the presser foot closed-loop control has improved
performance for a wide speed variation range.Fundação para a Ciência e a Tecnologia (FCT) – Project funding POSI/SRI/38944/2001