Objektive und subjektive Gesamtfahrzeugerprobung der Mehrlenkertorsionsachse (MLTA) – Eine bauraumsparende Hinterachse für BEVs

Autoren

J. Olschewski, X. Fang , T. Niessing – Universität Siegen

Zusammenfassung

This work describes the development and design process for a new rear suspension concept, which is especially intended for small BEVs. Especially in the A- and B-segment the twist-beam-axle (TBA) is widely used, which is mainly driven by the cost and weight efficient design possibilities. One of the main disadvantages is the limitation regarding the package space at the rear, caused by the torsionprofile. The basic idea was to reverse the installation direction of the Twist-Beam-Axle (TBA) to create additional package for the battery. Based on this idea, a new axle concept, the so called Multi Link Torsion Axle (MLTA), was developed as a part of a research project in collaboration with Ford, VW and other project partners.

One of the main development challenges was to obtain or even improve the kinematic behavior. This goal has been achieved by, the integration of the TBA into longitudinal oriented Watt’s linkage. This new arrangement leads to a battery volume in-crease of up to 30%. At the same time, the longitudinal kinematic behavior can be varied nearly independently from the torsion beam position by modifying the Watt’s linkage hard-points.

To achieve the defined kinematic elastokinematic target goals, various mathematical approaches were used to describe and optimize the mechanism behavior. Finally, the whole designed axle-module was manufactured and mounted to a modified Ford Fiesta body. The overall performance was rated with handling, ride and KnC Test, which were performed by Ford. The full-vehicle results were finally compared to the original and a mass modified Ford Fiesta.