Using Capacitance Sensor to Identify the Appearance Parameters of Slub Yarn

A heuristic approach was presented in this paper to identify the appearance parameters of slub yarn. The signal of slub yarn was firstly acquired with a capacitance sensor and a DAQ (Data AcQuisition) card. The slub yarn signal was then separated into some short parts based on a new local minimal amplitude based method. For each short part, an adaptive threshold was calculated and further adopted to identify the slub parts. Comparing with the global threshold, the local adaptive threshold reduces the negative affection of unevenness. Experimental results show that the presented approach works well.