Shock absorber design and analysis for off road race car

Abstract

The work involves shock absorber design and analysis for off road vehicles. Off-road race car is light and compact type vehicle so it is difficult to get shock absorber which exactly meet the required specifications. Shock absorbers for off road race car are expensive and difficult to get in local market. This ultimately raises cost of vehicle. Also, imported components do not allow in-house serviceability. The work started with studying the vehicle suspension requirements including performance & durability requirements, various technical parameters and design procedure. After that different component including piston, piston rod, cylinder, spring and orifice of shock absorber are designed using different mathematical formulas and theories. Shock absorber 3D modeling is done using CATIA V5. Then, structural analysis of shock absorber is done using ANSYS by considering three different materials such that: structural steel (ASTM A230), stainless steel (ASTM A313) and alloy steel (ASTM A231). The values of stress and deformation for ASTM A230, ASTM A313 and ASTM A231 are 487.45Mpa, 97.28Mpa & 97.49Mpa and 0.0674 m, 0.01345 m, 0.0129 m respectively. The ASTM A231 material has minimum values of stress and deformation among three materials. Therefore, for ASTM A231 material is selected as spring material. Further analysis is done by changing wire diameter from 10 mm to 7 mm to get optimized performance. The springs are to be designed for higher stresses with small dimensions to have better spring design which leads to save in material and reduction in weight. Therefore, 7 mm diameter is selected for spring. The weight of spring is reduced from 1.551 kg to 0.532 kg due to change in diameter.