The evaluation and calibration of pressure mapping system for the measurement of the pressure distribution of agricultural tyres

The accuracy of a commercial pressure mapping system was evaluated and a number of techniques for the improvement of pressure measurements were developed. These were required in order to use the pressure mapping system in a tyre/surface interaction study which involved determination of the tyre contact pressure distribution on, both, hard and soil surfaces. In the evaluation of the system, the effect of sensor calibration procedures on the accuracy of the system in measuring pressure was investigated. A purpose built pressure calibration chamber was used to calibrate the sensors, which enabled the proprietary built-in calibration system to be evaluated along with a novel calibration procedure employing, both, an individual and multi-point calibration of each sensing element and the rejection of sensing elements that did not conform to the sensitivity of the majority of the sensing elements. These measures reduced the uncertainty in pressure measurements from ±30% to ±4%. Further, evaluation of the compliance of the material was also conducted to enable the sensors to be used for interface pressure measurements between two different surface materials other than those used during sensor calibration. As a result, a procedure for normalising the recorded pressure by adjusting the recorded load output to equal the applied load was established. The improvement of the accuracy of the sensors made it possible for the system to be used to determine the pressure distribution resulting from a range of tyres on a hard surface and in the soil profile

Reduction in Water Erosion and Soil Loss on Steep Land Managed by Controlled Traffic Farming

Controlled traffic farming (CTF) is used to confine soil compaction to the least possible area of the field, thereby achieving economic and environmental benefits. In the context of climate change, soil erosion is one of the most discussed topics, and there is a research gap in understanding the effects of CTF on soil erosion in Central Europe. The aim of this work was to show the potential of CTF to reduce water erosion, in terms of water runoff and soil loss on steep land. A 16 ha experimental field with a CTF technology implemented since 2009 at the Slovak University of Agriculture was used in this research. Three traffic intensity locations were selected and watered using a rainfall simulator. The results showed that the soil which had not been wheeled for 12 years had the lowest water runoff: its intensity after 20 min of simulated rain was 10 times lower compared to the multiple traffic treatment. The soil loss, expressed as the total soil sediments collected after 35 min, in the no traffic area was lower by 70%, compared to the soil with one-pass treatment and only 25% of the loss in the multiple traffic areas. These results show that CTF can significantly reduce soil loss through water runoff on steep land