New driver models are included in the recent 2025.1 release of the VeSyMA – Motorsport library, which accompanies the new Dymola 2025x Refresh 1 release. These new motorsports driver models are streamlined versions of existing driver models in the VeSyMA – Suspensions library that are better suited to motorsports applications. The new driver models have unnecessary logic removed, more flexibility with the removal of final constraints, and new driver behaviour specific to motorsport added.
There are now motorsports variants of the following drivers:
- Closed-loop which attempts to achieve defined driving targets by considering vehicle metrics and adjusting the vehicle controls, replicating the actions of a ‘real’ driver.
- Single step test where the selected vehicle control is swapped from closed to open-loop control to perform a specified action at a defined time or distance. If you are interested in more information on the test driver models, see the previous blog post Test Sequence Driver.
Removal of Unnecessary Driver Logic
The VeSyMA – Suspensions driver models, which are primarily aimed at road car driving, include a few driver functions that are not typically required in a motorsport environment:
- Reversing
- Trailer reversing
- Gradients
- Handbrakes
While these aspects of the driver logic can be conditionally enabled or disabled in the VeSyMA – Suspensions drivers, it still means there is additional complexity and parameterisation that is simply unnecessary for motorsports applications. So the logic for these driver functions have been removed in the new VeSyMA – Motorsport drivers. The image below shows the lateral control used to determine the steering demand in the VeSyMA – Suspensions and VeSyMA – Motorsports driver models; it illustrates how much this one area of the driver can be streamlined by removal of the logic needed for reversing and reversing with a trailer.
Motorsport Specific Driver Behaviour Added
Alongside the removal of unnecessary driver logic, some new driver behaviour suited to motorsport applications have been included in the new motorsport drivers, with the option to:
- Not use the clutch while changing gear
- Have a fixed pull away RPM target
Removal of Final Constraints to Increase Flexibility
The VeSyMA – Motorsports driver models also offer more flexibility for experienced users, by lifting the restrictions imposed by the final constraint when defining and propagating parameters, and when redeclaring components.
To create the new VeSyMA – Motorsports driver models from the existing VeSyMA – Suspensions versions required modified motorsport variants of the planning, longitudinal control, lateral control, and gear-clutch control blocks to be created. New driver profile records, which define the driver model’s characteristics, have also been created to accompany the new motorsports driver models.
The vehicle experiment examples in the VeSyMA – Motorsports library now use the new motorsport driver models, but they remain compatible with the VeSyMA – Suspension drivers.
Written by: Hannah Hammond-Scott – Modelica Project Leader
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