DEVELOPMENT OF BRAKE AND TIRE TESTING METHOD USING A PLATE-BASED DEVICE

• Main Author: Muthoriq, Ery
• Format: Dissertations
• Language: Indonesia
• Subjects: Teknik (Rekayasa, enjinering dan kegiatan berkaitan)
• Online Access: https://digilib.itb.ac.id/gdl/view/79125
• Institution: Institut Teknologi Bandung

Traffic accident has become one of the major cause of death in Indonesia. It can be caused by vehicle failures such as braking systems and tire failure. These failures can be anticipated by periodic testing. However, testing with a test rig is only carried out for the brake, while the tire is only tested visually. Furthermore, the number of brake testers is still insufficient. Therefore, this research is aimed to develop a method for testing the brake and tire condition using a plate-based device. In this research, a plate-based brake tester is chosen because the brake tester currently used today, i.e., the roller brake tester, has several weaknesses. The first weakness is that the output of the roller brake tester is only one parameter, i.e., braking efficiency (maximum friction coefficient). Meanwhile, to test a tire, the data required are the friction force from free rolling until 100% slip. The other weakness is that the inertia of the test rig components is not taken into account. As a result, measurement on the roller brake tester is only accurate when the roller speed is constant. Whereas, when the wheel is braked, rollers will decelerate first before it achieves a steady state. To avoid these weaknesses, in this research, a testing method was developed using a plate-based device. This device is more accurate than the roller brake tester because the friction force sensor is directly attached to the plate. Hence, the measurement is not affected by the two roller's inertia. Moreover, the plate is moved at a low and constant speed. Because of that, the influence of the plate inertia on measurement can be minimized. Hardware has been developed in the form of plate-based equipment. This equipment consists of a steel plate supported by a linear bearing, a vehicle wheel above the plate, a load cell to measure friction force, and a linear potentiometer to measure the plate displacement. The plate is moved with a constant linear speed of about 1.1 mm/second when the wheel is braked. When testing takes place, a constant normal force is applied to the wheel. Thus, the data obtained are the friction force and the plate displacement when the plate is moved. These data are then approached by curve fit from the dynamic model and tire model. From data processing, three tire parameters have been identified, i.e., friction coefficient, slip when maximum friction force occurs, and tire tangential stiffness. The maximum friction coefficient (braking efficiency) describes the vehicle's braking performance. The slip at maximum friction force and tangential stiffness represents the tire condition. The tire condition can be determined if the vehicle's braking system is capable of making the wheel to 100% slip (the wheel does not rotate) when the plate is moved. Thus, by using the developed testing method, it is possible to determine the braking performance as well as the tire condition simultaneously.