Linkage Mechanism Optimization and Sensitivity Analysis of an Automotive Engine Hood

Abstract

Equipment such as a rod between vehicle body and hood or a lift strut are used to keep automobile hood in open positions during the regular maintenances or repairs. Moreover, some effort is required to open or close automobile hood because of its weight. To keep it in various opened positions and to exert the least force to open or close it, a mechanism is used in conjunction with extension, compression or torsion springs in two different configurations. Each optimization has been carried out for all these different springs, each in two configurations and results are compared. Sensitivity analysis for the design variables are examined to determine how these variables are influential on the designed mechanism. Optimization results of extension and compression springs are observed to be similar in both configurations of the designed mechanism. On the other hand, results for the torsion spring in two configurations are exactly the same for the mechanism. Sensitivity analysis shows that the designed mechanism is not sensitive on the design variables that are on the bound in both of these two configurations.    

Keywords

• Automobile engine hood,Linkage mechanism,Mechanism synthesis,Nonlinear optimization,Sensitivity analysis,Springs

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