COMPARATIVE ANALYSIS OF THE HEADLAND WIDTH WHEN MAKING T-TURNS BY A MOUNTED MACHINE-TRACTOR UNIT ON AN IRREGULARLY-SHAPED FIELD
СРАВНИТЕЛЕН АНАЛИЗ НА ШИРИНАТА НА ИВИЦАТА ЗА ЗАВИВАНЕ ПРИ ИЗВЪРШВАНЕ НА ГЪБОВИДНИ ЗАВОИ ОТ НАВЕСЕН МАШИННО-ТРАКТОРЕН АГРЕГАТ В ПОЛЕ С НЕПРАВИЛНА ФОРМА
Analytical relations for determining the headland width when making T-turns by a machine-tractor unit with a mounted machine on an irregularly-shaped field have been specified. Five types of T-turns are described in two variants – open turn and closed turn. Each of these is done in two directions of movement. A total of 20 variants of the turns are described. The method for determining the headland width of a specific machine-tractor unit consisting by a tractor and mounted row seeder is demonstrated. For each type of turn the headland width is determined according to the angle between the direction of movement of the agricultural unit and the field border. A range of angle modification from 10° to 90° is adopted. The analysis show that for obtaining minimum headland width closed turns in left to right direction of movement should not be made. The smallest theoretical headland width is when making a closed T-turn with arch-shaped backward movement and left-to-right direction of movement on the field. When using T-turns with an arch-shaped backward movement and T-turns with straight ahead movement when entering the headland, the actual headland width is the same (6 m) regardless of the type and direction of the turn.
Abstract in Bulgarian