The evaluation of soil tillage quality parameters, such as cloddiness and surface roughness produced by tillage tools, is based on traditional methods ranging, respectively, from manual or mechanical sieving of ground samples to handheld rulers, non-contact devices or Precision Agriculture technics, such as laser profile meters. The aim of the study was to compare traditional methods of soil roughness and cloddiness assessment (laser profile meter and manual sieving), with light drone RGB 3D imaging techniques for the evaluation of different tillage methods (ploughed, harrowed and grassed). Light drone application was able to replicate the results obtained by the traditional methods, introducing advantages in terms of time, repeatability and analysed surface while reducing the human error during the data collection on the one hand and allowing a labour-intensive field monitoring solution for digital farming on the other. Indeed, the profilometer positioning introduces errors and may lead to false reading due to limited data collection. Future work could be done in order to streamline the data processing operation and so to produce a practical application ready to use and stimulate the adoption of new evaluation indices of soil cloddiness, such as Entropy and the Angular Second Moment (ASM), which seem more suitable than the classic ones to achieved data referred to more extended surfaces.

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Modern tractors are characterized by the introduction of devices designed to increase the operative performances of the machines, such as systems for monitoring and controlling various functions (through a massive use of electronics and hydraulics), or deputed to improve the comfort of the driver (paying more attention to ergonomics, air-conditioning, noise and vibration). Such devices need energy to be operated, affecting the energetic balance of the tractor. In this context, the availability of suitable methodologies and instrumental systems could be useful to provide objective, accurate and reliable measurements of the performances of the tractors under different conditions, also considering the power requirements from ancillary services and/or simulating the coupling with operating machines. The tests on the performances of tractors are now made using different methods, including the trial codes issued by the OECD Codes. Beyond their undoubted validity, they fix standard test conditions that often do not adequately represent the operative reality, so that, much remains to investigate on the actual performances provided by the tractors. From this point of view and with reference to fixed point tests, a test bench was developed for the measurement of the power required by various devices, such as transmission and air conditioning. It was used in experimental tests on a tracked tractor and on a wheeled tractor, aimed at validating the test device, measuring the power absorption related to the rotational speed of the organs of propulsion and to the characteristics curves, in order to quantify the power drawn by the transmission and by the air conditioning and assess the residual power for other tractor functions. As to field conditions, a study is being conducted at CRA-ING, within the project PTO (Mi.P.A.A.F.), to develop a mobile test bench aimed at evaluating the power required by different operations, such as self displacement, traction, use of power take off, their combination. The system simulates such operations by applying to the tractor, by means of a system of sensors and actuators operated by feedback signals, work cycles combining force of traction, p.t.o. torque, hydraulic power, derived from data recorded during real field test with agricultural machines.

The use of lubricants and hydraulic fluids of both mineral and synthetic origin in agricultural processes could have a deep impact on the environment as a result of their possible dispersion in the ground and aquifers. Replacing them with bio-based fluids, developed to provide good tribological properties and high biodegradability, could contribute to reducing their negative effects. The evaluation of the capacity of such innovative fluids to replace the conventional ones is based on work cycles lasting as long as their lifetime, during which their characteristics must prove to be at least equal to those of the fluids they replace. To shorten the evaluation process, CREA (Consiglio per la Ricerca in Agricoltura e l’analisi dell’economia Agraria) developed a fluid test rig (FTR) and related test method, able to apply severe work cycles on small oil volumes, thereby accelerating the aging of the fluid beyond what typically occurs. This paper reports the results of the tests on FTR’s functionality carried out comparing two UTTO (Universal Tractor Transmission Oil) fluids: a widespread conventional fluid and an experimental vegetable-based oil. The FTR will permit, in a relatively short time, the assessment of the most promising formulations to be tested later under real working conditions, e.g., in agricultural tractors, reducing the risk of damage, before their ultimate introduction into the operating reality.

HighlightsLubricants are commonly used in agricultural activities involving machines.To reduce lubricants impact on the environment, a process has been started for replacing them with products obtained from vegetable oils.Tests have been carried out to explore the possibility of introducing vegetable-based UTTO in tractors.Results encourage to deepen the behavior of vegetable-based oils and develop specific test bench and methods.Abstract. To reduce the impact of mineral and synthesis lubricants on the environment, a process has been started for replacing them with lubricants and hydraulic fluids obtained from high-oleic vegetable oils, with good tribological properties, high biodegradability, and low toxicity. Test have been carried out at Research Center for Engineering and Agro-Food Processing of Monterotondo, Rome, Italy, with the aim of comparing the performances provided by a standard agricultural tractor supplied with conventional Universal Tractor Transmission Oil (UTTO) fluid and with a vegetable-based oil in their transmission-hydraulic system group. The research aimed at assessing differences, if any, in tractor’s performances attributable to the fluids in comparison. For a better comparison, the tests were carried out under controlled conditions, connecting the tractor, at first to a dynamometric brake used in engine and transmission tests, then to a test rig for hydraulic lifts. The results, although non generalizable, were encouraging, indicating that the tractor’s performances with the two fluids, after 30 h work cycles, were similar both for transmission and hydraulic lift. On the other hand, the reduction observed in the viscosity of the biofluid requires the deepening of the aspects related to its durability. The results also allowed to focus some basic aspects of the evaluation of biofluids and to identify some methodological approaches mainly based on the comparation of fluids performance during repeatable work cycles and on the assessment of how their physical properties evolve overtime. Keywords: Biolubricant, Engine performance, High-oleic sunflower oil, Hydraulic lift, Lifting force, Power transmission.