ศูนย์นวัตกรรมเทคโนโลยีหลังการเก็บเกี่ยว

Machine vision detection of early split pistachio nuts.

Pearson, T.C. and Slaughter, D. C.

Transactions of the ASAE. Volume 39, Number 3, 1996. Pages 1203-1208.

1996

บทคัดย่อ

Computer vision was used to detect early split lesions on the hull of pistachio nuts. Gray scale intensity profiles were computed across the width of the nut (perpendicular to the suture along the longitudinal axis). If the profile crossed an early split lesion, a deep and narrow valley on the profile at the early split location was observed. Profiles were computed every 0.5 mm along the longitudinal axis of the nut and the number of adjacent profiles with deep and narrow valleys was recorded. Early split nuts contained a significantly higher count of these adjacent profiles than normal nuts. Combining unhulled nut cross-sectional area with the adjacent profile data, 100% of the early split nuts and 99% of the normal nuts were correctly classified of the total of 180 nuts tested Two devices were developed to convey and orient unhulled pistachio nuts for presentation to a computer vision system. One device, which operated similarly to an "air hockey" table, correctly oriented 98% of the early split nuts and 99% of the normal nuts. The other device, which used vibration to convey and orient the nut in a "V" trough, correctly oriented 97% of the early split nuts and 98% of the normal nuts. A total sample size of 270 nuts was used to test each orientation device.