DESIGN, DEVELOPMENT AND EVALUATION OF A DEPTH-CONTROLLER FOR LASER LAND-LEVELING
This paper describes an improvement to land-leveling machines equipped with a laser leveling system. In a conventional automatic mode of a laser depth control system, the blade height is set by the laser control box with respect to a desired plane, which is provided via a laser transmitter. During leveling, if the cutting depth becomes too high, the power needed will be higher than the tractor drawbar power, and this will lead to extra load on the engine of the tractor and a decrease in engine speed. To prevent the overload on the land-leveling machine and tractor, the driver must quickly change from auto-mode of the laser system to manual and decrease the depth of cutting simultaneously. This needs a fast and skillful response from the driver. In order to prevent overload during leveling, an extra blade depth controller was designed and fabricated in this project. The designed system consisted of a closed-loop controller, which gets the real tractor engine speed via a dynamo. This was compared to values of critical and desired speeds of the engine that were defined by the user via a manual keyboard. These data were stored in the main microcontroller memory (programmed with 130 lines of codes with AVR-Codevision software), and displayed on an LCD screen. If critical engine speed is reached and the engine is overloaded, the system disrupts the laser control and raises the blade. The fabricated system was fitted onto a land-leveling laser machine and evaluated on a farm. The fuel consumption and field performance of the land-leveling machine were determined with and without using the fabricated system in operation. The test was conducted with five replications. Results showed a significant difference at the 5% level with an 18.4% reduction in fuel consumption and 19.7% increase in field productivity.
Masoumi, A.A., Shafaei, S.M., Gheisari , J. and Bayani , M.R. (2014). DESIGN, DEVELOPMENT AND EVALUATION OF A DEPTH-CONTROLLER FOR LASER LAND-LEVELING. Acta Hortic. 1054, 285-290
closed loop, control system, overload, fuel use, work rate