Mass flow control for manure spreader.

The objectives of this work were to improve the performances of the manure spreaders used by farmers. The principal aim of this paper is to show the chosen way to improve longitudinal distribution of this machinery. A prototype was developed and evaluated in Cemagref at Montoldre. The method consists in controlling the speed of the scraper conveyor regarding the height of the gate during the hopper unloading. The gate is able to follow the product profile. It is technically based on an electronic and automatic adaptation of the scrapper conveyor speed in regard with the alimentation section of the beaters and the spreader velocity into the field. For each product, the longitudinal flow rate result is improved according to the EN13080 Standard. Using this technique, the percentage of time spent in the tolerance zone is almost doubled compared to tests without control for the composted products and the longitudinal variation coefficient divided by 2 or 3 depending on the types of products.