DEVELOPMENT OF A PROFILOMETER FOR MEASURING SOIL TILLAGE PROFILE

Abstract

When tillage operation is carried out using tilling plough the soil is disturbed. The level of disturbed soil is determined by profilometer. An automated instrument was developed to determine the profile level of the ridges formed by the operation. The soil tillage profile meter consists of aluminum frame, two ultrasonic range finder to determine both horizontal and vertical distance, a dc motor and bidirectional motor control, microcontroller unit, data storage unit and liquid crystal display unit. The frame is 130 cm x 25 cm x 60 cm, the carrier and motor with two pulleys were attached to frame. The pulleys were 100 cm apart. The carrier conveying the two ultrasonic sensors: one pointing vertically down and the other pointing horizontally along the length of the aluminum frame with an obstruction (small plank) 100 cm away on the aluminum frame. As the motor is moving toward the obstruction the distance increases and when moving backward it reduces to zero. The values of the two distances measured were stored on the memory card. The time of the operation can be varied from 20 s up to 60 s. The accuracy of the finder used for measurement is ± 1 cm. The resolution is 1 cm. The Soil Tillage Operation Profile meter has maximum depth value of 200 cm and with 100 cm wide.