عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Introduction: Identifying and evaluating of variables that impact tractor performance needs correct size of the variables and their effects on parameters during the tractor operations. So it is necessary to measure accurately performance parameters for improving draft performance of tractor. Generally, there must be a proper assessment and identification from operational parameters such as forward speed, slippage, drawbar pull, etc. In this regard, a lot of research has been conducted using various methods to measure and calculate these parameters under various soil condition and different implementations for achieving the maximum overall energy efficiency, analyzing various treatments and predicting experimental models. But to change soil physical properties and different reactions of machinery on the one hand and to do operations related to on the other hand, precision agriculture intervals between the measurement of performance parameters and making decision for applying operational changes in real condition of work should be as short as possible. These conditions are required to be an accurate system with high confidence ratio for executing, measuring and recording simultaneously in farm. Therefore it is necessary to develop data acquisition for calculating field performance parameters in new methods of farm management.
Materials and Methods: In this study, nine different sensors were installed on a MF399 tractor for recording engine and wheel speeds, drawbar power, and fuel consumption. A processing unit was designed and the performance parameters values of tractors-implement were fed into a software to a maximum of 1000 data per second real time, and also remotely from 1.5 km distance in Excel Sheet .Early stage testing of different combinations of the nine sensors included pre-installation on the tractor with four wheels on the jack (In workshop, on tractor) and on the farm and asphalt.
Results and Discussion: The results showed that for engine and wheels and the fifth wheel speed sensors (actual forward speed) are accurate the slip was calculated real time using ultrasonic flow meters with 150 cc.min-1 flow rate The lowest fuel consumption was related to the no load and stationery is also possible. About draft, load cell measures 10 Nm real time.
Generally, to identifying and survey the effect of various variables on performance parameters of tractor-implements, also designing automatic control system, SSCM and spatial variability in accurate agriculture depend on accurate and precise performance data measurement and correct measurement of variables and changes of parameters during operation execution at the same time. So the installed system is designed in such way that it can measure real-time wirelessly 9 main variables to a distance of 1500 meters with max 1000 data per second including forward speed, speed of all wheels, engine speed, net fuel consumption, drawbar pull and performance parameters such as OEE% (overall energy efficiency), SFC (lit/kw-hr),SE (specific energy in Mj/ha), AFC(Ha/hr), average slip of rear and front wheel(%) , drawbar power (kw), draft(kn/m), FCha(lit/ha)… which are calculated based on the nine variables and display data in tables and graph on pc and finally save separately and totally measurement results and all raw data (pulses) in 10 worksheets into an excel file for any sensor.. It is obvious that number and type of parameters, measurement unit and table display are editable in averaged form and totally this system is installable on common tractors with trivial changes in Iran. However, RTPM (remote tractor performance monitoring) was tested in real conditions of work and of library and its performance was found to be satisfactory. With a tractor equipped with an accurate measurement tool and data acquisition unit, this study tries to make actual interval between receiving, processing and displacing data while it provides the right analysis of recorded changes for controlling automatically and applying instructions with types of operators installed on tractor or mounted instruments on it. Finally, it displays measurement results in such a way that they are understandable not only for researchers and designers of agricultural machineries but also for a regular operator. The system can be installed with minimal changes on all conventional tractors in Iran.