More than ever, the automotive industry operates in a highly competitive environment. Manufacturers must deal with market pressure and with conflicting demands from customers and regulatory bodies regarding the vehicle functional performance, and are thus forced to develop products of increasing quality in even shorter time. Primary vehicle functional performance attributes are the handling characteristics and driving dynamics, ride comfort and active safety. The use of electronic control units enables new strategies to improve the vehicle performance. The increasing integration of electronic and mechatronic content leads to a next generation of intelligent vehicles, however also to a drastic increase of vehicle system complexity. Dealing with this complexity on a functional and system integration level is a major challenge from the vehicle design and development process perspective. Product quality, customer satisfaction and safety can only be achieved when engineers are able to manage this complexity in the product development process, and this from the concept stage onwards. This requires to fundamentally rethink the vehicle design and engineering process. In this paper, this rationale will be worked out for the chassis and suspension design process, in view of achieving optimal vehicle driving dynamics in terms of ride and handling, driving pleasure, stability management and safety. Innovative solutions in vehicle dynamics systems have lately been introduced to enhance the vehicle stability management. From a full vehicle design perspective, these innovations (ABS, ESP, active suspension, active steering...) however remain to a large extent on the level of add-on systems and a major need exists to integrate all functionality on the vehicle level using a systems approach. Configuration and performance optimization, system integration, control, component, subsystem and system-level validation of these intelligent systems must be an intrinsic part of the vehicle development process, just as today this is the case for structural, vibro-acoustic and kinematic design. Using a systems engineering approach to design the complex innovative chassis and suspension systems, one can predict and optimize the performance of intelligent vehicles based on integrated virtual simulation and physical prototype testing. A key element herein is the integration between discretized-geometry-based models (3D FE and MBS models) and multi-physics system models ('conceptual' 1-D or 0-D models) for simulating complex devices (e.g. hydraulics, actuators, specific sensors...) and processes. The combination can take place on the level of time integration of the state equations (embedding or co-simulation) or by reducing the 3D model into an approximative state-space 'plant' model. Embedding control laws paves the way to Model-ln-the-Loop (MiL) and Software-In-the-Loop (SiL) applications. By linking the virtual models to actual hardware systems on a physical test-bench, the static and dynamic performance of the rest of the vehicle system (suspension, body...) can be represented, enabling 'Hardware in the Loop testing' (HiL). The development of real-time virtual models for complex systems is however still a major challenge. When physical prototypes are available for the components, subsystems or system, the actual testing and calibration of the controller connected to physical prototypes can be performed (rapid prototyping). The validation in a 'Vehicle-in-the-Loop' configuration finally allows the evaluation of all system dependencies and system interconnections. Typical examples in chassis and suspension design will be discussed, such as models for active suspensions and active safety systems. Key recent advances in simulation technology will be discussed, including advances in detailed 3D subsystem modeling and vehicle dynamics simulation technology, the creation of real-time simulation models from detailed 3D models, the conversion of system models from 3D to 1D and vice versa. The models can be used to concurrently optimize the structural and the component design values as well as the control laws and control parameters.
Simulation-based design of vehicle chassis and suspension for optimizing the driving dynamics performance
Simulations-basierte Entwicklung von Fahrzeugrahmen und -aufhängung zur Optimierung der Fahrdynamik
2009
11 Seiten, 10 Bilder, 16 Quellen
Conference paper
English
Chassis suspension driving device and chassis damping method
European Patent Office | 2022
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