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Title: A sensor system and related models to determine irregular shaped 3-D objects in crop handling applications
Author: Gall, H.
Awarding Body: University of Edinburgh
Current Institution: University of Edinburgh
Date of Award: 2001
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This work comprises several parts, the initial one of which is a review of the techniques in use at present for measuring shape and characterising products. The major work details a ring sensor system, which consists of a large number of transmitters and receivers alternately arranged on the circumference of a metal annulus. Using a modified polar co-ordinate system and trigonometric functions, two enveloping spirals of an object can be determined. One or both spirals can then be used for further data analysis. Each spiral consists of intersections between enveloping chords and parts of the chords. The area surrounding the object is segmented and properties such as volume and axis measurements can be determined. A model was developed to simulate artificial objects of various shapes. Simulation tests were carried out to determine the limits of the system concerning position within the ring, shape and speed of the object and resolution of the ring. A ring was manufactured for actual tests, which were carried out mainly on potatoes to confirm the opportunity for possible use in practice and to show the relative merits compared with existing systems. Interesting side issues are introduced, such as the low number of primary data, possibilities of further reduction using differential coding, and the time consumption of algorithms. Finally, a model for the simulation of more than one object in the ring at the same time is introduced and possibilities for their separation are investigated.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available