Development of a Machine-Road Simulator for Performance Investigation of Height Measuring Sensors in Earth Moving Machinery

Nowadays, a vast range of construction and agricultural machines, such as tractors, graders, scrapers, and back hoes are equipped with computerized control devices for earth moving processes. The main job of these devices consists of the topography surveying, cutting and filling of elevated and spotted low area, and these actions depend on machine ability in elevation and thickness measurement and control. In this research, an apparatus was designed and manufactured for performance investigation of thickness and height control unit using ultrasonic-based transducers. An endless conveyor is devised instead of the real field or road; a carrier of control unit is used instead of the vehicle body and a programmable moving probe is designed analogous to machine actuator or blades. They were integrated to work similarly with an automated vehicle. An ultrasonic height measuring unit was developed and mounted on the carrier and gauge blocks of different thickness were arranged to feed the conveyor unit as a requirement of executing the designed statistical test. Accuracy, repeatability, and resolution were chosen as the main variable of performance qualification. The results show the capability of this procedure in recognition of sensors' behavior and improvement of field machine control system. Inspection, calibration and response diagnosis of the elevation control system in combination with machine function can also be evaluated by some extra development of this system. This research has produced a simple laboratory device to investigate the performance of measuring units for height and thickness with high precision.