Nowadays an automotive industry steadily has been growing and playing a major role on economy development for many years. The crash box is one of the most important parts for safety but it was found that the crash boxes manufactured domestically are not met international standard requirements. This is due to process and material limitation. This process for automotive safety test requires high budget and there is unclear approach for specific test. Therefore a study of crash boxes referred to energy absorption project was conducted as an alternative choice of testing. Regarding to the problems as addressed above this project was aimed to design and test crash boxes which come in various structures; simple type corrugated type and honeycomb type of crash box. In addition it was also emphasized in studying energy absorption behavior and physical deformation of crash boxes after dynamic and static energy being applied. Numeric simulation and static test methodology of front collision were applied for these tests in reference to USA NCAP standard for automobile collision test. Testing all types of crash boxes indicated that the corrugated type was able to absorb energy at 2.8% and 5.9% higher than honeycomb type and rectangular type respectively. This is capable to pickup stress and strain continually and effecting to more energy absorb than another type. Additionally this corrugated structure is feasible and suitable for crash box design in automotive manufacturing.

A disc brake is one of important auto parts for motorbike cycle industry which effected directly to life safety. As the result this project aims to test the performance of the disc brake in order to study the physical disc brake that effects to braking distance and to be an alternative for testing the brake disc. The braking performance tester was designed and created in the single dynamometer which was not over 10 Hp and the 17of inertia .70 kg. m. Referring to testing state of JASO T204:2001 standard this tester focused on testing the 3 different types of disc brake i.e. normal type grooving type and perforated type. The tested temperature was at normal state of the brake disc temperature (60° C - 80° C) and at high state (more than 100° C). The braking force from 9.81 N to 34.33 N at master cylinder was tested. moments was not over 92 The result revealed that at normal temperature the braking performance of the three disc brakes (normal type grooving type and perforated type) was at 17.76 21.80 and 19.00 per 1 mrespectively. However the brake performance at high temperature was at 14.41 18.06 and 18.93 per 1 m. This meant that the most efficient disc brake at normal temperature was grooving type of disc brake which was 22.74% different from normal type of disc brake. Nevertheless; the perforated type of disc brake was the most performance disc brake at high temperature which was different from normal type of disc brake at 25.32% 2 of contact surface areas 2 of contact surface areas respectively2m/s2m/s

Nowadays the automotive parts industry greatly grows up in Thailand. Brake disc is one of products that play a role in safety area. As a result the various designs such as front and back-vented brake discs are occurred to improve the performance of usability. Consequently this study aims to develop the ability of braking dynamometer from 9.7 kg-m.1 kg-m. Moreover the influence of the front and the back-vented brake disc effecting on braking distance was investigated by single dynamometer referenced JASO C406 for testing condition. Therefore both of discs were operated under 100 200 and 300 °C of braking temperature and 2 4 and 6 MPa of line hydraulic pressure of braking. 2 to 1272 of moment of inertial From experimental works the test results reflected that the back-vented brake disc created braking distance shorter than front-vented brake disc ostensibly. Besides there are also diversity of factors as temperature pressure and initial speed of braking. Especially the higher temperature caused an increase of deceleration and a decrease of braking distance. Moreover the higher pressure produced a deduction of braking distance and a rise of deceleration. Finally the initial speed of braking was directly various the braking distances in same condition.

The aim of this project is to study the fuel consumption from the effect of tire pressure and tray volume. In order to tire pressure is consist of 2 conditions by: Road test and Roller test Bench. Their test is classified by 3 cases: standard tire pressure lower standard tire pressure and upper standard tire pressure. Furthermore the lower and upper standard tire pressure was compared with standard tire pressure. In case of seal and unseal of the tray volume was test with 2 postulates by Road test and water tunnel (model). The results of experiment with 3 cases of tire pressure found that the lower standard tire pressure (25/37 psi) given to the maximum fuel consumption when compare with standard tire pressure 4.6%. While the minimum fuel consumption is upper standard tire pressure (33/45 psi) or 1.29%. Furthermore the trend of those conditions was in the same direction. For the result of test in term of seal and unseal of the tray volume discovered to the fuel consumption in case of seal is lower than unseal of the tray volume 1.63%. And the result of test of the water tunnel has been the same direction with the Road test.

Nowadays one of the automotive engineering is conductivity of brake pads playing a role in friction coefficient which means safety of customer. Thus thermal properties have been improved using composited materials. This project aims to study the conductivity behavior of 3 different brake pads which are supported by the company Compact International (1994) Ltd. For experimental works temperature based on brake condition was simulated from 200 to 400°C and cooled down from 400 to 200°C at 1 5 and 8 MPa of pressure respectively. By standard JIS D4413 testing condition of pressure was referred. The non-linear of conductivity value are calculated from the temperature under steady state condition. As a result of testing there are several of parameters effecting on the non-linear conductivity value. The brake pad that is a mix of high-fiber occurs the fluctuation of thermal conductivity. At the same time lubricant in the brake pad cause the stability of conductivity value in different temperature range at the same pressure. On the other hand the brake pad mixed hi-copper inspires the narrow range of conductivity value in different pressures at the same temperature. Moreover the conductivity value as a mention is inversely proportion with the coefficient of kinetic friction.