Detection and Removal of Contaminants in Cotton

Introduction

Cotton collected from fields by the workers contains different types of contaminants such as seed coats of the cotton seed, human hair, beedi tips, bird feathers, husks, plastics, papers rugs, etc. These contaminants hinder the spinning of yarn; affect the quality of thread and subsequently the weaving of clothes. The presently used methods like plane thresholding, scanner system, Chinese technique based on comparison method have their own limitations. In order to overcome these limitations a system with the application of image processing based on hue thresholding and masking the plane has scan developed.

The system consists of three major parts - PC based machine visions, image processing and controls. These broadly include CCD camera, Image grabber/processing card, personal computer, Fluorescent lamp, 16 pin BNC connector and Digital I/O etc. The contaminated cotton kept in a transparent case is subjected to light which focuses the image by means of lens on the camera and image is grabbed by means of image grabbing unit. The said image is processed by computer program to display the contaminants. The intensity of light generates the control signal for driving away the contaminants. Contaminants upto 0.1 mm size and almost all the defects other than pure cotton can be detected. The system is independent of physical positioning of cotton and probability of contaminants. With the progressive scan camera, the system can scan the object at a speed of 1000 m/minute.

Salient features:

The system can work with poor lighting and one light source; All types of contaminants could be detected; Detection of contaminants while the tuft is in motion is possible; A low cost system using simple white light.

Prospective Users: Exporters and processors of raw cotton, spinning mills.

Type of Technology: Machine vision system and Software

Status of IPR Protection: Indian Patent Application no. 926/DEL/2002 dated 12.8.2002 with title "Machine Vision System to detect contaminants from cotton"

Status of Development: Working prototype has been built and tested from the end use requirement point of view.

Major Equipment & Facilities required: Basic fabrication and assembly facilities are required with an investment less than Rs. 50,000

Glossary: PC: Personal Computer; CCD: Charge Coupled Device; I/O: Input/Output

Services offered by Technology Transfer: Know how manual including circuit diagram, etc.Process demonstrationTraining of personnel for a period of 10 working days

Developed by : Prof. Sekahar Chandra / M S Ishtiaque
Department: Instrument Design Development/ Textile Technology

Contact:

Managing Director
Foundation for Innovation and Technology Transfer (FITT)
Indian Institute of Technology, Delhi
Hauz Khas, New Delhi-110016, INDIA
Tel : 91-011-26597167, 26857762, 26581013, 26597153
Fax : 91-011-26851169
E-mail : drkdpn@gmail.com