Use of agricultural machinery for soil mobilization

The use of agricultural machinery for soil mobilization and its energy consumption comprise one of the highest costs on rural properties. Among the technologies available for agriculture, the use of data acquisition systems and computer programs, which generate important information related to the parameters of agricultural machines and can measure the soil mobilization force in real time and thus make the operation more profitable and suitable for every need.

Many agricultural operations carried out on rural properties feature some type of mechanized activity in search of better results in operational efficiency and economic return to the rural producer. This intensification of mechanized processes in the field must be correctly dimensioned, efficiently relating the tractor, tool and soil set.

The agricultural operations used in the implementation of a crop, from soil preparation to harvesting, can mostly be mechanized and, therefore, present great efficiency and economic return to the producer, as long as they are well conducted using technology and suitable machinery (Duarte Júnior et al.

The use of agricultural machines and tractors is required for soil mobilization and the energy consumption of these equipment comprises one of the highest costs in agricultural operations on rural properties. Energy demand is directly linked to factors such as the suitability and condition of the tractor-equipment set, depth of operation, type and condition of soil, total number of operations used, geometric configuration of tools, among others.

The need for rural producers to loosen their soils for agricultural production means they depend on the use of soil mobilization tools such as scarifiers and subsoilers in order to correct this limitation.

Lances (2002) states that the scarifier is an implement, whose function is to promote the disintegration of the soil, from bottom to top, carrying out mobilization up to a depth of 35cm. It is similar to a subsoiler, but working at shallower depths and with smaller spacing between rods.

In relation to soil disruption, the same author also mentions that the scarifier rods mobilize the soil in a three-dimensional propagation (forwards, to the sides and upwards) of the cracks, that is, the soil is not cut as in plowing or harrowing. but rather broken at its natural fracture lines through the interfaces of its aggregates.

Among the technologies currently used in agriculture, it appears that the use of sensor systems, electronic data acquisition systems and computer programs enable the collection and processing of a high volume of data capable of generating important information related to the parameters of agricultural machines. .

The concept of sensors to relate soil physical properties, compaction measurements, simultaneous mapping of mechanical resistance at different depths and water content has shown to be a promising approach, significantly aiding the knowledge of soil physical variables and, potentially, increasing in the efficiency of agriculture (Adamchuk et al.

Based on the aforementioned concepts, research was carried out in the agricultural experimental area belonging to the Tokyo University of Agriculture and Technology, located in the Fuchu District, city of Tokyo, Japan, with the objective of developing a system for measuring soil mobilization forces. in real time using information technologies. The university provided a research center in the areas of precision agriculture and agricultural mechanization and provided technologies for the instrumentation of agricultural machinery and equipment.

Plowsoiler agricultural equipment manufactured by the company Sugano Farm Machinery was used. The equipment consisted of a metal platform mounted next to the agricultural tractor's three-point hydraulic system and offered support for the allocation of rods with deflectors up to 7cm wide. To carry out the tests, a specific model of equipment was used with support for only one scarifying rod, adapting to the test conditions and the specifications of the small tractor.

To determine travel speeds, a GNSS receiver from the Hemisphere GPS Smart Antenna was installed next to the agricultural tractor, with an e-Dif differential correction system.

Three Kyowa electrical resistance extensometers, model KFG-5-350-C1, were used, installed next to the agricultural equipment to measure soil mobilization forces.

The three electrical resistance strain gauges called sensor ch1, ch2 and ch3 were installed on the rod of the agricultural equipment and calibrated using a load cell measured by comparing the signals generated by the sensors with the values ​​generated by the load cell. The sensors were positioned on the rod according to Sakai et al (2005)

To collect the data, three Kyowa electronic data acquisition systems, model DBU-120, with a frequency of 100Hz were used, responsible for collecting the signals generated respectively by the ch1, ch2 and ch3 sensors installed on the equipment shaft. A Panasonic Toughbook 30 industrial computer was instrumented next to the agricultural tractor and used during the tests to collect and store data in real time and simultaneously between the ch1, ch2 and ch3 sensor channels.

A wooden structure was built to adapt the installation of the industrial computer, the power battery and the three data acquisition systems. The wooden structure was fixed next to the scarifying equipment. (Figure 1). 

The set was responsible for collecting data generated by the ch1, ch2 and ch3 sensors installed on the rod and by the GNSS receiver installed on the agricultural tractor. To determine the horizontal (Fx), vertical (Fy) and resultant (F) force requirements requested by field operations, a rod instrumented with electrical resistance strain gauges was used according to Liu et al (1996) and Sakai et al (2009), illustrated in Figure 2.

As an example of the results collected, Figure 3 illustrates the mobilization forces of collecting temporal data from the ch1 sensor, for treatment at a working depth of 35cm.

Based on the results of soil resistance, through load cells with georeferenced position by GNSS receiver, obtained by the instrumented rod, real-time intervention in compacted layers at variable depths or subsequent management based on area mapping is possible. .

Machado (2013) developed and evaluated a prototype of instrumented rods, capable of reading the soil resistance, in three different layers, in real time, commanding the scarifier to decompact the soil when necessary, as well as collecting information for mapping the layers for management purposes.

The author verified that the rods performed similar soil mechanical resistance readings to the penetrometer, having an acceptable correlation with R2 = 0,79.

 The use of this type of equipment in agricultural management can allow rural producers to make better use of agricultural equipment, reduce energy consumption and increase operational capacity.

The agricultural tractor equipped with sensor systems, electronic data acquisition systems, GNSS system and industrial computer proved to be suitable for conducting the field tests proposed in the work. Under the tested conditions, the instrumentation of agricultural equipment for soil mobilization proved to be adequate to evaluate the horizontal (Fx), vertical (Fy) and resulting (F) forces.

Field trials demonstrated that the system can produce results that highlight spatial variability in agricultural areas with a high degree of sampling density and also present a more efficient and dynamic operational capacity compared to surveys carried out with conventional methods.

Gustavo K. Montanha, Fatecbt; Saulo PS Guerra, Unesp; Fernando H. Campos, UTFPR; Marcelo S. Denadai, Unesp

Article published in issue 159 of Cultivar Máquinas.