Design of Front Cab Suspension System for a New Generation Volvo Trucks

Abstract

The cab suspension of a truck constitutes the connection of the cab to the frame. Its main task is to suspend the cab from harmful excitations coming from the frame since the life of cab structure and the comfort of driver is mostly dependent on these vibrations. In modern trucks, the entire main truck manufacturers use four-point cab suspension, which means cab, is suspended in both front and rear side of the cab. The main task of this thesis work is to create different solutions to cab suspension problem of the new generation (NG) trucks. The design and development phase of NG trucks is continuous till the product is launched which results in change of boundary conditions during the thesis project. This report complies with the changes made till January 2005. The thesis work starts with the product planning phase, where all the requirements of the product are established, analysis of the main competitors is done and new ideas are generated through brainstorming sessions. The second part is composed of the development phase, where the ideas generated in the product planning phase are developed into final products satisfying the targets set in the planning phase. In this part of the thesis work, two different approaches to the problem are introduced. The first approach is mainly concentrated to solve the problem different suspension mechanism, namely instead of using conventional suspension mechanisms, other alternatives satisfying the requirements are analysed. The second approach is mainly concentrated to change of suspension type, which proposes to use different solutions other than conventional air or mechanical spring types. Results of the development phase leads to different solutions applicable to new generation trucks. As the final steps, all solutions are compared with the requirements as well as the current solution. In conclusion, there are two different mechanism change proposals and alternative suspension type changes which comply with all the requirements for the product, which can be adapted for future design changes.