Fast Conception (FastCon) – A tool for concept design and optimization of twist beam axles 2020-01-0920
The common development phase of a TBA usually starts with several concepts, based on benchmarking or empirical values. Based on these concepts the first CAD Models are designed and then converted into FE- and MKS models, so that the stiffness and kinematic characteristics can be evaluated. From these first results, it can be estimated which concept is suitable to fulfill all the requirements. The selected concept will be further optimized via numerous CAD and CAE iterations until it meets all concept targets. Due to this process, the quality and the development time of the final development strongly depends on the chosen concept.
The presented algorithm FastCon-TBA (FastConcept Twistbeamaxle) is a development tool, which simplifies the process described above and makes it more efficient. Based on the concept variables FastCon analytically evaluates all relevant kinematic and elastokinematic characteristics. To calculate the properties each part of the TBA is idealized as a beam. Each beam element can have a specific orientation and crossection, which allows to approximate the deformation behavior of the TBA. Considering the boundary conditions and external loads each beam deformation is calculated. By superpositioning all the deformations the complete deformation behavior can be described. Furthermore, Fastcon allows to couple the TBA deformation with bushing properties, so that for example toe correcting effects also can be taken into account.
FastCon combines this calculation with an optimization Algorithm. By using a marking system the multi-dimensional non-linear optimization problem is reduced to a scalar optimization. So an optimal concept according to the given boundary conditions (eg. Package space) and the requirements can be developed in a few minutes.
Based on an example calculation this paper shows the development process with FastCon and the results compared to an FE Modell. Another Example shows how FastCon is used to develop a concept with a given package space of a production vehicle, and then comparing it to the serial twist beam axle.
Jens Olschewski, Xiangfan Fang, Kanlun Tan