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While the existing research provides a wealth of information about the static properties of RTK receivers, less is known about their dynamic properties, although it is clear that the vast majority of field operations take place when the machine is moving. A new method using a MRA for the evaluation of RTK receivers in movement with a precise circular reference trajectory (r = 3 m) was proposed. This reference method was developed with the greatest possible emphasis on the positional, time and repeatable accuracy of ground truth. Four phases of the measurement scenario (static, acceleration, uniform movement and deceleration) were used in order to compare four different types of RTK receiver horizontal operation accuracy over three measurement days. The worst result of one of the receivers was measured at SSR = 13.767% in dynamic movement. Since the same “low-cost” receiver without an INS unit had SSR = 98.14% in previous static measurements, so it can be assumed that the motion had a very significant effect on the dynamic properties of this receiver. On the other hand, the best “high-end” receiver with an INS unit had SSR = 96.938% during the dynamic testing scenarios. The median values of the deviations were always better during uniform movements than during acceleration or braking. In general, the positioning accuracy was worse in the dynamic mode than in the static one for all the receivers. Error indicators (RMSerr and Me) were found several times higher in the dynamic mode than in the static one. These facts should be considered in the future development of modern agricultural machinery and technology.

The objective of this paper was to test the suitability of Doppler microwave radar for the detection of wild animals hidden in grassland in front of the harvester. The ability of Doppler radar HB100 sensor to detect a dog or a human person hidden behind different types of crops was tested in laboratory conditions. Relative movement between the radar and the observed object was secured by the assembly acting as mathematical pendulum. The radar always moved in front of different crop samples (arranged in two or one line). The dog or human person was situated behind the crop. In five out of seven cases, the sensor was able to detect the human person. Only in two out of seven cases, the sensor was able to detect the dog. Nevertheless, it can be concluded that microwave radar sensor can be a useful device for detection of wild animals in the crop. Next research is needed in order to better explain the influence of disturbing factors on the measurements.

Lev J., Shapoval V., Bartoška J., Kumhála F. (2017): Low-cost infrared sensor for wildlife detection in vegetation. Res. Agr. Eng., 63 (Special Issue): S13-S17.The protection of wild animals from mutilation or being killed during haymaking is still a serious problem connected with high working speeds and widths of modern harvesting machines. That is why the main aim of this study was to test low-cost, high-speed and low-noise infrared array sensor Melexis MLX90621 for the application of wildlife detection with the potential to be used in front of the mower equipment. The tests with two different crops with or without a hidden dog were made. Results showed that the sensor is able to detect an animal hidden in the crop with very high probability. Nevertheless, direct sunlight conditions can cause the problems when using infrared technology. A simultaneous use of other sensors working on different principle than infrared technology can be thus recommended.

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