If a product consists of several discrete, rigid bodies that touch or abut each other or are coupled, for example, via joints, springs or dampers, it is called a multi-body system. In the context of product development, it is of great importance how the individual components behave in interaction and which interactions occur.
The analysis by means of physical prototypes takes a lot of time and leads to high costs. Multibody simulation makes it possible to represent such mechanical or mechatronic systems as virtual models. Forces, movements and vibration quantities occurring within the systems can also be calculated. MKS delivers very accurate results in a relatively short calculation time. The virtual comparison of different variants not only improves the product quality but also shortens the development time considerably.
If you do not have your own simulation department or if you want to outsource particularly large and complex CAE projects for capacity reasons, we can support you as an engineering office specializing in simulation throughout the entire process chain or by taking over individual tasks. In addition, we will be happy to advise you on developing and establishing your own simulation processes.
With SIMULIA Simpack, we use the world's leading software in this field for our multibody simulations. As an official distributor of Dassault Systèmes we work closely with the developer, so we always use the latest version and have access to all current modules. Our powerful IT infrastructure enables us to calculate a large number of variants in a very short time. If required, we often combine MBS with other simulation methods such as the finite element method. Thanks to the versatility of our company, we can also carry out additional measurements to validate the virtual results on request.
From simple wheel suspensions to robot delta kinematics and other high-tech products - the motion sequence of kinematic systems can be analyzed in the early development phases using a virtual MBS model. In this way, a large number of different kinematic systems can be tested and compared with each other in a short computing time. The products can thus be optimized, for example, in terms of efficiency, service life and production and maintenance costs.
The focus of the kinematic analysis is to examine and optimize the movement itself. Deformations of the body itself are usually not yet considered in this preliminary analysis, but can be investigated in the later development step Dynamics.
By analyzing the component dynamics with respect to position, velocity and acceleration, critical operating states can be identified. With this knowledge, either the operating parameters or the kinematics can be adjusted accordingly to avoid excessive loading and thus prevent damage.
In some cases, it is necessary to consider the structural elasticity in order to be able to reproduce the component behavior exactly and optimize it effectively. This includes, for example, contact problems and acoustic problems. In addition to the purely kinematic simulation, the dynamic behavior of the overall structure is also analyzed here on the basis of a virtual 3D model. The number of complex and expensive physical tests can thus be significantly reduced. This is particularly relevant when the commissioning of the entire system under load is only possible at the end customer's site.
To take into account the elasticity of shafts, gears or complex components such as rotor blades, flexible bodies are integrated into the model. Depending on the requirements, the level of detail can vary: From simple elastic elements such as springs or dampers to simplified contact models and the complete integration of elastic components. For this purpose, the MBS model is coupled with an FEM simulation. Individual components previously calculated with SIMULIA Abaqus, ANSYS or NASTRAN can be directly integrated.
The product quality can be further improved with downstream analyses, e.g. regarding lifetime or acoustics.
Typical applications in this area are:
- analysis of torsional vibrations in drives
- analysis of the effects of play and other production-related tolerances
- analysis of the propagation paths of vibrations in machines
- identification of vibration-endangered components/assemblies in development
- virtual testing of various remedies
No matter where a gearbox is used, the aim is always to ensure that it runs vibration-free, reliably and quietly. Even minor malfunctions often make themselves felt loudly and can result in a considerable loss of yield and high wear.
Prototype tests on a test bench often only provide information on performance under ideal conditions. In addition, it is time-consuming and cost-intensive to test and compare different variants. Using simulation at an early stage in the development process, allows for the performance to be examined under a wide range of operating conditions and for its optimization from the outset. In addition, critical operating areas can be identified and specifically avoided.
As a rule, it is not sufficient to consider and design all components individually. In order to develop an optimally functioning system and thus be able to fully exploit its potential, rather, the interaction of the components must be considered. Therefore, multi-body simulation is particularly suitable for transmission development and optimization. If the elasticity of the components is also to be taken into account, FEM calculations can also be included.
Our service portfolio in the field of transmissions:
- Calculation and optimization of the force distribution in the transmission
- Optimization and modification of the gear teeth
- Identification of vibration endangered components
- Calculation of force and moment progression
- Analysis of gearbox operating vibrations and simulation of remedial measures
- Visualization of the trajectory
- Stability tests (eigenvalue analysis)
- Run-up and resonance analysis (Campell diagram)
For multi-body simulations of gears, we use SIMULIA Simpack, a highly professional and powerful software with specialized modules like Gear Pair.
The ideal vision of rail travel? Fast, quiet, comfortable, reliable. To ensure that the passenger notices as little as possible of the rough wind outside the wagon or that goods, for example, reach their destination safely over many years of use, a great deal of development work has to be carried out long before the train comes onto the rails. In addition to comfort, safety, wear, and noise reduction play a central role.
With the help of multibody simulation, new carriage concepts for modern and efficient rail transport can be optimally developed. Virtual test drives can save costly trials with physical prototypes. Based on an exact MBS model of the locomotive, wagon and wheel truck, numerous application scenarios such as, for example, a switch crossing under various driving conditions can be simulated very efficiently. Parallel to the analysis of the driving dynamics, the chassis parameters can be optimized and the wear of wheel and rail can be investigated. Simulation models are becoming more and more important in supporting the verification of vehicle technology, which can even partially be replaced.
Simulation for determining the driving characteristics of railway vehicles according to DIN EN 14363:
|Evaluation and optimization of the ride comfort in the interior (passengers, train conductor, personnel) DIN EN 12299|
|Clearance profil & vehicle gauge||Simulation of the clearance gauge for planning and for the determination of the vehicle gauge according to DIN EN 15273 (EBO, BOStrab, internal company guidelines)|
Simulation and optimization of the wheel-to-rail contact for
|Proof of strength||Proof of strength for components within the scope of approval and component analysis for optimal and safe design|
|Crosswind / Wind characteristics|
Calculation of wind characteristics according to RIL807.04, EN 14067-6 and TSI HS RST
Consultation on crosswind detection of passenger vehiclesPreparation of expert assessments for the crosswind verification of passenger vehicles
e.g. according to RIL 807.04, EN 14067-6 or TSI HS RST
|Accident cause analysis||Accident analysis via simulation and preparation of expert assessments|
|Infrastructure||Simulation of switches and track in connection with vehicle dynamics|
For our services in rail vehicle technology, we cooperate with the company Simtes, which has many years of simulation expertise in the rail vehicle sector. In particular, we rely on the expertise of Prof. Rolf Naumann and Simtes for approval-relevant simulations, the calculation of wind characteristics, crosswind verifications and the preparation of expert assessments.
Machines cause vibrations and noise – usually undesirable, but often unavoidable. These emissions are often referred to as NVH – Noise, Vibration Harshness – and can become a problem not only in terms of worker protection legislation, but also in terms of product quality and machine life. NVH is becoming more and more relevant as a result of the constant quest for greater efficiency and the associated higher workload.
With the help of numerical simulation, the vibroacoustic behavior can be precisely analyzed and improved on the basis of structure-borne noise, i.e. structural vibrations. Compared to tests with physical prototypes, not only time and costs can be saved, but also more accurate results can be achieved and more variants tested. Based on the results, effective vibration and noise minimization measures can then be developed.
- Identification of the sound radiating components
- Evaluation of model variants for design optimization
- Examination and interpretation of mitigation measures, and
- Optimization of the operating behavior
Basically, NVH is relevant in almost all industries. Typical fields of application for simulations in this area are drive technology and mechanical engineering. As an illustrative example, tonalities, i.e. individual frequencies that can be heard as tones within a sound, are particularly problematic in wind energy. These are penalized with a surcharge on the total sound power level and thus often lead to yield losses.
- Elastic modelling of the components involved
- Simulation of structure-borne noise and radiation behavior
- Subsequent simulation of the airborne sound by modelling and calculation of the air elements
- Extrapolation to reference point and evaluation of the influences on the total sound level