Our client, a US based start-up, had licenced a US Patent (No. 6,526,120) for a novel, contact-free and supposedly-accurate method of measuring grain. The premise of the patent is that if grain (or indeed any other product) is free-flowing through a pipe it is possible to measure the mass of the product by continuously recording the X-ray absorption of the product in the pipe - the greater the volume of product flowing, the higher the absorption.

The appeal of this approach was that it potentially eliminated the need for weighbridges and provided a mechanism for automated asset managment. For the large-scale grain production in the US, which makes significant use of rail freight, this was very appealing. WyeTec's brief was to assist in producing a prototype system to prove, or otherwise, the claims in the patent, and provide the basis for a commercial product.

The project started with a meeting with the patent author and a tour of their research rig. It soon became apparent that, whilst the basis of their research appeared to be good, there were significant improvements that could be made in the methodology.

A mono-block X-ray source with RS232 controllable kV and mA was selected, allowing the optimum X-ray conditions to be selected on a per-installation basis. Key to the source selection were the power output, shielding requirements, weight and MTBF. A single-energy linescan device was selected for X-ray detection, and a custom designed i/o card was integrated to monitor the status of safety interlocks, grain-bin selection switches and other inputs. The prototype system yielded an extremely pleasing level of accuracy, justifying further development towards a full demonstration system.

WyeTec developed software to integrate the devices, perform and retain system calibration, and to perform measurements and inventory management. On completion of the project, the client was provided with all drawings and source code, allowing them to produce systems locally.