Mehrkörpersimulationsgestützte Fahrradentwicklung

• Multibody simulation based bicycle design

Ingenlath, Philipp; Corves, Burkhard (Thesis advisor); Bertram, Torsten (Thesis advisor)

Aachen (2019, 2020)
Dissertation / PhD Thesis

Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2019

Abstract

The development process of bicycles is frequently governed by the principle of trial and error. Compared to the development processes in other industries, simulation methods are only sparsely employed to support bicycle development. The present work covers the application of multibody dynamics simulation techniques on the field of bicycle technology. The dissertation is divided into a first part that covers classical bicycles without suspension systems and a second part that covers full suspension bicycles. In the first part of the work the riding dynamics of bicycles without suspension systems are investigated. To achieve this aim the Carvallo Whipple model is used. Additionally, to cover the rider’s behaviour, a model derived from control theory is utilized. Both models have been covered extensively in the literature. To assess riding dynamics, a metric regarding the criteria stability, agility and cornering ability is derived. In the second part of the work, a multibody simulation model of a full suspension bicycle with a rider is developed. The model is parameterized using measurements of a specific bicycle. The rider model is formulated on the basis of anthropometric databases. It is parameterized such that it complies with the size and weight of the test driver employed to gather the validation data. Subsequently, validation measurements for the behaviour while pedalling and while traversing an obstacle are taken. Simulated and measured data are found to be in good agreement. Thus, the developed model is able to capture the dynamic behaviour of the full suspension mountain bike with a rider. Evaluating the model reveals that contemporary quasistatic design criteria are a major simplification and consequently using a complex multibody model is beneficial. The utilised rider model however only covers untrained/inexpert riders. The mapping of experienced driver behaviour, e.g. active shifting of weight for control purposes is not covered by the model. Overall, multibody simulation techniques are shown to be a suitable tool for bicycle development.

Institutions

• Chair and Institute of Mechanism Theory, Machine Dynamics and Robotics [411910]