Abstract: Since assembly errors of parts can lead to deviation of motion trajectory of sewing machine with the result that the problems like feed poor and puckering appear, evaluation method of feeding performance based on error analysis of motion trajectory was proposed. The error feature indicators of alternative simulation models and ideal system were extracted by error analysis feature extraction method. Error feature index weights were computed by objective assignment method depending on design objective, and correlation degree was calculated by weighted grey correlation model, and a reasonable evaluation index system and integrative evaluation model was built. Finally, the proposed method was applied to feed mechanism of lockstitch sewing, the relational degree of each assembly errors model and ideal system was judged from the corresponding probability output, therefore the feeding performance was evaluated. The result shows the effectiveness and validity of the proposed approach.

Key words: motion trajectory, error analysis, feeding performance, grey relational analysis