Accurate time control of eliminating the cotton foreign fiber

The related time periods of eliminating the cotton foreign fiber in a machine vision system were analyzed in detail in this paper. The impact factors relating to eliminate cotton foreign fibers in every related time periods were expatiated fully and clearly. A new method of detecting cotton flow speed in a pipeline by ultrasonic velocity sensors was proposed. The formula for evaluating the cotton flow speed was also derived. An algorithm for calculating the precise time interval from having detected the foreign fiber to sending the open instruction to jet valve was presented.