Akshay NANDA works as CAE Analyst at Mercedes-Benz R&D India. Akshay has around five years of experience in NVH simulations and is currently supporting rear axle whine simulations for Mercedes-Benz Cars.
Model Reduction Methodology for Large-Scale Gear Design Optimization
Developing transmission with optimal NVH performance is one of the biggest challenges in the automotive industry due to the shift towards quiet electric drives. Gear whine, a structure-borne vibration of the transmission system, has emerged as a significant NVH concern. Static transmission error is considered a key factor causing gear whine and therefore has also become a standard parameter for gear-train NVH optimization. However, the dynamic response of hypoid gear systems is a complex combination of various other time-varying mesh parameters like the movement of mesh point and mesh stiffness variation. Evaluating the dynamic response of the hypoid gear driveline system is computationally costly and, therefore, cannot be directly used as a parameter for large-scale design optimization. We have developed a reduced-order simulation model, which can accurately predict the dynamic response of the hypoid gear system within a few seconds, thus allowing it to be used directly as a parameter for optimization. Also, many simulations are required to analyze the robustness and sensitivity of the gear design to various manufacturing and assembly uncertainties that can now be performed efficiently.
Atsushi TSUBOUCHI joined Honda Motor in 1998 and was involved in performance-based design considering automotive vehicle dynamics. After that, Atsushi moved to a Formula One car development department in the UK and was in charge of the dynamic behavior based on the measurements and the CAE results The experience in the formula car showed him great potential in the integration of CAE into IT infrastructure. Currently, Atsushi is responsible for the platform development, performance-based design, and development process re-engineering in chassis design.
Vision for Performance-Based Design Using Simpack Vehicle Dynamics as a Digital Innovation
Digital solution with CAE technology is mandatory in automotive vehicle dynamics, such as handling and ride comfort. Especially, virtual verification with Multi-Body Simulation (MBS) is becoming more and more essential to provide a specification of each component. On the other hand, MBS has a challenge in shortening the entire workflow, including calculation, verification, and its management, due to the complexity of the model structure. The speed and robustness of the Simpack solver are expected to resolve it in combination with an efficient workflow in the design process. This presentation introduces a Simpack workflow for handling and ride comfort and its future vision, bringing efficiency to vehicle development.
Bjorn VAN UEM is a well-known multi-body dynamics and vehicle dynamics expert within the automotive and motor racing industry. He holds more than 15 years of experience in multi-body simulation for a broad range of applications, such as ride comfort, handling, durability, powertrain, driveline, integration with control systems, and driving simulators.
Bjorn joined Jaguar Land Rover in 2015 as an MBS Development Group Leader and moved in 2019 to his current role, Manager – MBS Cluster & D&R CAE.
In his current role, he is now responsible for standardizing, advancing, and rolling out MBS simulation across many departments within Jaguar Land Rover to improve the efficiency of the product development process and facilitate well-informed engineering decisions.
Further, he is responsible for the vehicle program simulation support for Loads (MBS), Wading (CFD), and Underfloor Vulnerability (FE). Before joining JLR, Bjorn worked as a Mechanical Simulation Engineer at Mercedes AMG HPP, Brixworth, and a Technical Director at SIMPACK UK, Leicester.
Simpack Wizard at JLR: Methods Development and Durability and Robustness Programme Support
An overview of how Simpack Wizard is used at JLR across many departments, from vehicle dynamics to NVH, to standardize simulation methods and work with a single model concept built and released by a central team. As an example of vehicle program support, the Durability and Robustness team's Virtual Road Load data process will be presented.
Christoph RUDHART, born in Friedrichshafen, Germany, earned his Ph.D. in Theoretical Physics from the University of Stuttgart. After entering Daimler AG in 2008, he held several positions in the Departments for Powertrain Development and Chasis Systems. His main field of work is the Simulation of Ride Comfort with Simpack.
Simpack @ Mercedes-Benz Passenger Cars Development
Since its introduction in 2019, Simpack has become the primary tool for multi-body simulations in developing passenger cars at Mercedes-Benz. Applications range from predevelopment and predesign of chassis systems over durability calculations to ride comfort and NVH. The large variety of applications leads to many models and load cases with different states of complexity. To handle this, Simpack Wizard is used in combination with a customized Automotive Database, covering all the load cases and model variations, while keeping the common basis of the models as large as possible. The presentation gives an overview of the applications of Simpack in Mercedes-Benz passenger car development.
Gakuto NAKAYAMA has been successful in many projects to reform the development process of major manufacturers at foreign-affiliated companies. In 2005, Gakuto founded Progress Technologies, Inc. to promote further reformations from the customer's perspective and to develop new technologies.
In addition to supporting the product development of many manufacturers, Progress Technologies also developed and launched the world's first eOneBook reader, designed to give e-book readers a whole new reading experience. Gakuto has a track record of supporting start-up companies such as AI and robotics.
Vision for Performance-Based Design Using Simpack Vehicle Dynamics as a Digital Innovation
Digital solution with CAE technology is mandatory in automotive vehicle dynamics, such as handling and ride comfort. Especially, virtual verification with Multi-Body Simulation (MBS) is becoming more and more essential to provide a specification of each component. On the other hand, MBS has a challenge in shortening the entire workflow, including calculation, verification, and its management, due to the complexity of the model structure. The speed and robustness of the Simpack solver are expected to resolve it in combination with an efficient workflow in the design process. This presentation introduces a Simpack workflow for handling and rides comfort and its future vision, bringing efficiency to vehicle development.
Biography:
After studying Mechanical Engineering at the Technical University Prag, Czech Republic, Jan ZEMAN completed his diploma thesis at Skoda-Auto, using the Multi-Body System (MBS) simulation software Simpack.
In 1999, Jan started working for the SIMPACK AG as a Project and Support Engineer, focusing on the simulation of Vehicle Dynamics (application areas: handling, ride, driveability, durability, NVH). From 2009 to 2014, as the “Product & Project Manager Simpack Automotive”, he was responsible for the Automotive product, customer project, and account management.
Following the acquisition of the SIMPACK AG by Dassault Systèmes in 2014, Jan is now focusing on the SIMULIA MBS/Simpack pre-sales management and strategic key customer engagements in his current role as SIMULIA Multibody Simulation Industry Process Expert Director.
Title: R&D Update on Multibody System Simulation
Abstract:
This presentation will give you an overview of the general R&D updates of the multibody system simulation software Simpack.
We will show you the latest software updates in Simpack, including a few of the updates from the last two years. Further, we will provide an update about application-specific functionalities.
Johannes AMBERG studied Mathematics at the Technical University of Munich. After completing his studies in 2006, he joined SIMPACK AG as a project and application engineer.
In 2012 Johannes joined Fendt, which is part of AGCO. At Fendt, Johannes works within the development department. There he is responsible for the multibody simulation cases as a member of the system simulation team.
Simpack and FTire in High Horsepower Tractor Applications
First and foremost, a tractor had to do its job reliably — while driving-comfort taking a back seat. But nowadays, a driver also wants a comfortable driving experience.
In tractors, tires are a prominent part of the suspension system. It is impossible to fulfill the simulation scenarios' increasing requirements concerning comfort analysis with our current tire model. Because of this, we started a project together with cosin scientific software, parameterizing a pair of agricultural tires for our 900 series tractors. Because of the large tire sizes, we could not use current tire test rigs to get the tire parameter results. Hence we used a complete tractor as a test bench. In order to evaluate the tire forces, we set up the tractor with a lot of measurement equipment, especially wheel force transducers. Even though a challenging approach, we found this to be the right way to find a suitable parameterization for our simulation. We now can simulate all of our simulation cases with the generated parameter file for FTire.
Juhwan LEE is currently a Senior Engineer at the Hyundai Motor company. There, Juhwan is responsible for the NVH analysis of powertrains and motors. Juhwan holds a master's degree in Mechanical Engineering from Korea University.
Multibody Dynamics Analysis and Reduction of Powertrain Rumbling Noise
Recently, consumers' expectations for sound quality are increasing, not only for expansive vehicles of medium-sized or higher but also for small and light vehicles. Among the noise sources, the rumble noise is harsh and unpleasant. Generally, the primary sources of rumble noise are crankshaft and powertrain bending.
In this paper, we analyzed the period and timing of occurrence of rumble noise by measuring noise and engine vibration in a vehicle. In addition, the test results were used to verify the dynamic analysis model of the crankshaft considering the hydrodynamic lubrication characteristics. Based on the validated analytical models, a major cause of rumble noise was analyzed. A method for improving the leading cause was studied, and the effect of the clearance between the crankshaft and journal bearings was analyzed considering the hydrodynamic lubrication characteristics.
Ludovic GRANDJACQUES obtained his engineering degree in 2007 from SUPMECA Paris, gaining with it a solid mechanical knowledge merged with recognized expertise in IT development.
He has since been working at Stellantis (ex PSA) as a Numerical Methodology and Multibody Simulation Specialist Engineer. His dual expertise has enabled him to develop various middlewares, which perfectly adapt to different MBS and FEA software, meeting the needs and constraints of end-users.
These developments cover many automotive scopes, especially where multibody simulation needs an accurate and performing solver (Chassis, Powertrain Mount, Full Vehicle Load Predictions) and where standardized design processes require strong automation of calculation and post-processing.
Thanks to a brand-new API, provided in a record time by Dassault Systèmes, these middlewares are interfaced since 2017 with SIMULIA Simpack.
Ludovic’s favorite pastime is to help his fellow engineers by solving complex engineering problems by providing simple technical applications, getting his reward out of knowing that every single car produced by “his” company has been designed with the help of his solutions.
Stellantis Approach for Simpack Usage: Automation
The wide use of multibody simulation in the company by non-expert users has always required the use of middleware, making it possible to adapt the calculation tool to the group's standards, methods, and ways of working.
Today, around 150 people use Simpack every year, almost exclusively handling these middlewares as an entry point, allows the fusion of calculation expertise and automotive design processes without having to adapt one to the other directly.
Manohar H C works as CAE Analyst at Mercedes-Benz R&D India. Manohar has around seven years of experience in NVH Simulations and is currently supporting front axle whine simulations for Mercedes-Benz cars.
MBS-FE Simulation Methodology for Front Differential Whine Noise
Front Differential Whine noise is a major concern and is a structure-borne vibration of the driveline due to Hypoid gear excitations. Identification of the vibration transfer path and optimizing the relevant structural components is the key to the solution.
We used Simpack to develop a flexible MBS model similar to the test bench considering the excitation from the Hypoid gear. MB Simulations were performed and a critical frequency where the response has to be reduced was identified. In general, mass and stiffness are varied to provide a solution for reducing the response at the critical frequencies. However, this approach is not optimal as it does not help to determine the exact location of the structure to be modified. We analyzed in detail mode shapes of the flex states contributing most to the vibration response at the critical frequency. The operating mode shape at the same critical frequency was reestablished in FE for structural optimization by using cutting forces from previous MBS analysis. MBS simulations were repeated on the optimized structure to verify the developed methodology.
Marc LÄSSING graduated in 2000 as a Diplom-Ingenieur of Automotive Engineering at the University of Applied Science in Esslingen.
From 2000–2002 Marc worked at the former DaimlerChrysler AG as a CAE engineer at the Research & Technology Center for Vehicle Dynamics, having his first contact with Simpack.
In 2002 Marc joined the Daimler Commercial Vehicles CAE center for NVH Powertrain analysis. Marc is responsible for full vehicle simulations focused on drivetrain-induced vibrations and SiL co-simulation using Simpack and the center-wide Simpack installation.
Optimization of NVH Launching Performance of a Heavy-Duty Truck using Simpack as FMU in Interdisciplinary Co-Simulation
Modern trucks today use mainly automated manual transmissions, including automated clutch control. Launching behavior primarily depends on electronic clutch control and various hardware parameters like clutch friction behavior or clutch friction pad stiffness. To optimize the launching behavior regarding NVH and the performance, a full vehicle model including ECUs for engine, clutch, and transmission control was created, using Simpack as FMU inside an in-house co-simulation tool. Hardware parameters and software versions were evaluated to improve the launching behavior.
After studying Mechanical Engineering at the Technical University Munich, Germany, Marcus Schittenhelm completed his diploma thesis at BMW, using the Multi-Body System (MBS) simulation software Simpack.
In 1997, Marcus started working for the SIMPACK AG as a Project and Support Engineer, concentrating on the simulation of Complete Vehicle Dynamics (application areas: handling, ride, driveability, durability, NVH, real-time) and Mechanical Engine Dynamics (application areas: crank train, timing mechanism, valve train). From 2003 to 2014, as the “Director Simpack Automotive/Engine”, he was responsible for the product management, customer project management, key account management, and worldwide Simpack business development for the SIMPACK automotive industry sector.
Following the acquisition of the SIMPACK AG by Dassault Systèmes in 2014, he’s now focusing on the SIMULIA MBS/Simpack product management, strategic partnerships, and worldwide key customer engagements in his current role as SIMULIA R&D Director Portfolio Management.
R&D Update — Vehicle Dynamics
Robert BUCHMANN studied Mechanical Engineering at the Technical University of Munich (TUM) and graduated (M.Sc.) in 2018. After his studies, he joined the Institute of Mechanics of Professor Lion at the Universität der Bundeswehr in Munich as a Ph.D. candidate with a research project in cooperation with MAN Truck & Bus SE. The aim of the project was the entire virtual vehicle proving ground testing of busses for durability analysis.
Therefore, to analyze the durability of the frame structure, a multidisciplinary simulation process with a virtual prototype of the vehicle driving over digitized test tracks has been implemented.
Virtual Proving Ground Testing of MAN Commercial Vehicles for Durability Analysis with Validation and Identification of Dominating Mode Shapes for Structural Optimization
Customer and legislation in the transportation sector demand the development of disruptive commercial vehicle concepts to include new electrical drivetrains and batteries. For an early analysis of the structural durability of commercial vehicles, a virtual prototype was used. A virtual full vehicle test on digitized test tracks was implemented and validated for the durability analysis of bus frame structures within a research project. In this presentation, the simulation process, with emphasis on the flexible multibody simulation model and validation with measurements results, is shown. Furthermore, based on the modal contributions to the stress history, the approach for determining dominating mode shapes is described, and an example for a critical location is presented.
Robert KALCHER is a PhD student at the Institute of Mechanics, Faculty of Mechanical Engineering and Economic Sciences at the Graz University of Technology. There he received his BSc and MSc in Civil Engineering in 2009 and 2013, respectively.
In 2014 Robert received a Diploma Degree in Automotive Engineering from the University of Applied Sciences FH Joanneum Graz.
Currently, Robert works at AMSD Advanced Mechatronic System Development as a Development and Simulation Engineer for the automotive sector. Robert's research interests include nonlinear dynamics and multi-body systems.
Modeling of BEV Powertrain Mounts in BMW Complete Vehicles using Simpack MBS
Because of legal requirements and based on the general trend towards electrification, the amount of battery electric vehicles (BEVs) within the fleets of vehicle manufacturers increased steadily in recent times.
BMW is no exception with its current series production BEVs i3, i4, iX3, and iX. In general, BEVs deploy electric axle drives (EADs) as powertrain units at the front and/or rear axle. Furthermore, EADs are usually mounted to the vehicle's body or subframe via elastomer mounts.
Since such BEV powertrain mounts significantly influence the vibration comfort of the complete vehicle, the elastomer mount modeling and parameterization is a crucial and challenging task. Therefore, the work at hand deals with the MBS modeling of elastomer mounts, the associated fitting, and the subsequent incorporation of complete vehicle models within Simpack MBS software.
The virtual development process regarding vibration comfort using the module Simpack Wizard and its corresponding automotive database will be presented based on a case study.