Vehicle simulators are increasingly understood within the automotive industry as an alternative to physical pre-prototype building and testing and in giving vehicle dynamics analysts, who are normally relatively distant to the subjective test drive process, feedback of accurate and realistic ‘feel’ from their vehicle dynamics models. They can contribute to the development of components and systems in steering, ride and handling, tyres, HMI and ergonomic assessment, problem investigation, software debugging, competitor assessment and benchmarking and engineer training. More settings can be changed and more options evaluated in a simulator than would ever be feasible in the real world, due to budget and time constraints.
There a lot of very advanced automotive simulators in use but still not every OEM has one.
We find their adoption is very dependent on the culture and acceptance levels of each OEM, both from within the senior management and engineers. Some management teams are vehicle dynamics people at heart; true ‘car’ people that still get a thrill out driving the cars at test tracks themselves and which give personal input to the development process in the traditional way. Others are very fact-based and business process driven and are therefore much more welcoming of the data that can be generated by a simulator to help drive decision-making.
Saying that, the idea to investigate motion simulation is often driven by a certain engineering team within the OEM, say the steering or NVH team, which recognises its value to achieve a specific goal. Then more people come on board and a simulator development project is born.
No ‘one size fits all’ simulator
In the OEM automotive engineering space different applications will require different simulators. For example, for ride and comfort evaluation, you need limited stroke, high frequency, high bandwidth simulation with direct drive actuators. In contrast, ride and handling testing requires much lower (below 20 Hz) bandwidth and larger stroke.
OEMs may have an array of simulators for different things. A central simulator may be used for evaluating handling maneouvres such as elk tests and lane changes as well as automatic cruise control and driver observation systems. Then there might be a separate one for ride and comfort where engineers experience a ride rather than a drive which can be useful for comparing engine mount A versus B or testing out new dampers. We know of one manufacturer which has a set-up which can test the shifting experience of its gear box on one simulator, for example and the steering on another; it depends on the driving dynamic which is most key to the brand.
Due to the growing expertise among automotive simulator engineers, there is now a much greater appetite for more control over and customization of the simulator’s motion behaviour.
This is something we’re supporting by allowing our customers to go beyond basic parameter tuning and to be able to custom design algorithms and command direct platform set points from within the Simulink environment.
The increase in computing power is another big factor influencing the world of simulators. So much more can now be done in real time. Together with advancing graphics cards, the visuals are also getting better; in fact they are improving every three to six months or so. Vehicle models can be a lot more complex these days because the calculation power is so good that you can do more in the same time. You can make your car model more detailed and calculate it more accurately and add more parameters.