Mathematical Modelling and Simulation of a Torsional Bar Actuated Trunk Lid Mechanism for a Passenger Car

This paper is concerned with the design and analysis of a rear trunk lid mechanism which is used in sedan passenger cars, and actuated by torsional bars. First, the mechanism actually consisting of a four bar linkage is designed regarding certain kinematic aspects. Afterwards, a mathematical model is developed to determine some requirements crucial to design process such as the equilibrium positions and the opening velocity of, and the required hand force to open and close the trunk lid. By dimensioning mechanism and choosing torsional bar stiffness properly, a trunk lid mechanism is obtained, which meets the demands of the higher first equilibrium angle and significantly small hand forces. Hence, this paper presents a practical and easy methodology in the design and analysis of a trunk lid mechanism for design engineers.