Albert Lutz

Developments in vehicle dynamics and the tire model performance test

Aspects of the vehicle dynamics like handling, ride, comfort, and durability as well as of controlled subsystems are discussed. The increasing importance of simulation to support the development and application process of vehicles with control systems is shown. The role of the tire and the corresponding tire models is highlighted and requirements for the modeling and parameterization of tire models are derived.

Virtual Test Drive in the Application Process of ESP®-Systems to Ensure Performance and Robustness

Vehicle dynamics simulation is a well established tool in the function development and in software testing of ESP®—the Electronic Stability Program. Due to an increase of vehicle variants, additional ESP® features, legal requirements and the pressure to increase the overall efficiency in the development process vehicle dynamics simulation is becoming more and more a part of the ESP® application process. For this purpose increased requirements of the simulation models, the set-up process of the simulation environment and finally the test cases have to be met. This paper describes the ESP® specific simulation methods, the environment and the related process between OEM and supplier to set-up and run the simulation platform commonly. Examples are presented which are applied in two phases in the application process. One is the frontloading process to set-up an initial mature software (SW) supported with simulation. The other one is the handling of projects with a large amount of vehicle variants. In both cases simulation is used to ensure the performance and robustness of the overall vehicle and ESP® system.

Simulation methods supporting homologation of Electronic Stability Control in vehicle variants

ABSTRACT Vehicle simulation has a long tradition in the automotive industry as a powerful supplement to physical vehicle testing. In the field of Electronic Stability Control (ESC) system, the simulation process has been well established to support the ESC development and application by suppliers and Original Equipment Manufacturers (OEMs). The latest regulation of the United Nations Economic Commission for Europe UN/ECE-R 13 allows also for simulation-based homologation. This extends the usage of simulation from ESC development to homologation. This paper gives an overview of simulation methods, as well as processes and tools used for the homologation of ESC in vehicle variants. The paper first describes the generic homologation process according to the European Regulation (UN/ECE-R 13H, UN/ECE-R 13/11) and U.S. Federal Motor Vehicle Safety Standard (FMVSS 126). Subsequently the ESC system is explained as well as the generic application and release process at the supplier and OEM side. Coming up with the simulation methods, the ESC development and application process needs to be adapted for the virtual vehicles. The simulation environment, consisting of vehicle model, ESC model and simulation platform, is explained in detail with some exemplary use-cases. In the final section, examples of simulation-based ESC homologation in vehicle variants are shown for passenger cars, light trucks, heavy trucks and trailers. This paper is targeted to give a state-of-the-art account of the simulation methods supporting the homologation of ESC systems in vehicle variants. However, the described approach and the lessons learned can be used as reference in future for an extended usage of simulation-supported releases of the ESC system up to the development and release of driver assistance systems. Abbreviations: ABS: Anti-lock braking system; ADR: Australian design rules; ALB: Automatic load-dependent brake force controller; AMEVSC: Alternative method to assess the electronic vehicle stability control system; APP: Application; BSC: Brake slip controller; CAE: Computer-aided engineering; CAN: Controller area network; CAT: Category; CoG: Centre of gravity; DIN: Deutsches Institut für Normung (German Institute for Standards); EB+: Trademark of Haldex; EBD: Electronic brake force distribution; EBS: Electronic brake system; ECU: Electronic control unit; ESC: Electronic stability control; ECVWTA: European Community Whole Vehicle Type Approval; FMVSS: Federal motor vehicle safety standards; GPS: Global positioning system; GRRF: Groupe de travail en matiere de roulement et de freinage (Working Party on Braking and Running Gear); HiL: Hardware-in-the-Loop; HSRI: Highway Safety Research Institute; K&C: Kinematic and compliant (KnC); MBS: Multibody systems; MPV: Multipurpose vehicle; NHTSA: National Highway Traffic Safety Administration; OEM: Original equipment manufacturer; SiL: Software-in-the-Loop; ST: Summer tyres; STM: Single track model; StVO: Straßenverkehrsordnung (Government Highway Regulations); SUV: Sports utility vehicle; SW: Software; SwD: Sine with dwell manoeuvre; TC: Threshold consumption value; TCS: Traction control system; TRIAS: Test Requirements and Instructions for Automobile Standards; UN/ECE: United Nations Economic Commission for Europe; VAF: Value-added function; VDC: Vehicle dynamics controller; VTC: Vehicle test catalogue; WT: Winter tyres

TMPT – conclusions and consequences for the industry from the industry

After a short introduction, the first part of this publication shows the main topics of vehicle dynamics from the computational simulation point of view: vehicle handling, comfort and durability. It is discussed, which effects of the physical tire behavior are included in different tire models for simulation. Additionally limitations of these models are given briefly. In the second part, the tire parameterization process is shown, starting from the tire measurement to the release of the tire data set. One essential point of this process is the validation and plausibility check of the virtual tire behavior. Finally, the general requirements of tire models are discussed, based on the results of the Tire Model Performance Test. The acknowledgment of the virtual tire characteristics is a fundamental part of correctly interpreting simulation results for decisions in the development process.