Evaluation Of Redesigned Parts Considering Analysis, Production And Distribution Factors

Whenever a new or improved design is proposed, it is important to consider more than just the technical aspects of the new design (e.g., safety, deformation, strength, weight). It is essential to take into account several additional factors in the total production cycle of the new or improved product. Ideally, every factor in the life cycle of the product should be taken into account. As part of a Capstone Design Project, and with the goal of illustrating complete engineering design processes where factors besides the technical ones need to be taken into account, industrysponsored projects are undertaken by teams of students. The project presented here deals with an automotive subassembly that needed to be redesigned and evaluated. The system is a power slider assembly which is installed in the rear of current-model trucks and powers the rear window. The current design is bulky, expensive, and takes too much time to install. The objective of the project was to introduce a new design for the power slider which would be more efficient in terms of operation, assembly process and delivery cost. A CAD model was created for the proposed design including new design features. Free body diagrams representing forces and couples acting on the system were evaluated using Finite Element Analysis (FEA.) Based upon FEA results, the design will sustain a maximum stress of 33.9 MPa concentrated at the lower segment of a new snap feature, thus yielding an acceptable safety factor. Failure Mode and Effect Analysis (FMEA) showed potential failures and their possible causes. The proposed design was prototyped and cycle tested to recommended standards, which provided evidence that the proposed design was ready for production. Benchmarking costs of the proposed design versus the current design was done. Significant benefits were found when stress analysis factors were taken into account alongside with manufacturing, production and distribution factors, thus illustrating the importance of a complete evaluation matrix. This project presented an excellent opportunity for the team of students to be exposed and actively participate in a real-life engineering design environment. The sponsoring industry is a tier I supplier to the automotive industry who provided very strong support towards the success of this senior design project. The feedback received from students was that they had learned a great deal and the experience was very rewarding.