Racecar Lap Simulation
Setting up a racecar is complicated and time-consuming. Whilst you hope every setup change will make you faster, in practice, this is never the case. With many types of setup changes taking an age (“let’s change the diff again!”) and with track time-limited, what you are after is to eliminate as many setup dead ends as possible. Racecar lap simulation seems like the answer.
Racecar lap simulation to the rescue (sort of …)
Professional motorsports teams all now use some form of modelling or racecar lap simulation software. This enables them to try many more setup options in the time available. With their racecar lap simulation done, they can be more confident their real setup changes will be an improvement.
For your interest, professional simulation software includes ADAMS, VI-Grade, Dymola, Matlab, AVL as well as others. These codes power teams (driver-in-the-loop) simulators (below), chassis setup optimisation, electronic control strategies, race strategies and support several other areas of racecar research and development. They are really powerful and useful tools.
These pro-grade simulations are great but they require a lot of investment (think 5 figures per seat) and a lot of time and expertise to get the value from them.
What Are Your Other Options?
1 – DYI
Once you have some of the basic vehicle dynamics theory behind you, you might be tempted to have a go at building your own lap simulation model. This is not as difficult as it sounds. Many people (aka students mainly) do build their own lap simulation tools and these are a great endeavour.
If this is something you are interested in pursuing yourself, then there are several open-source models and resources out there to help you. These are mainly using Python and Matlab although podcast guest Andrea Quintarelli built his original one in Excel. If you are up for this then you will probably like this guy’s videos as well. He takes you through a step by step process on how he is building his with access to his code as you go on.
2 – Midway
Sadly options are limited for those looking for something in the middle ground between Pro and DIY.
There used to be a free lap time simulator programme from Bosch called LapSim. If you do some Googling for this you might find it (last seen free about 2009 … now it costs ‘000s!)
Dynatune-xl by Paul Fickers is another option you could consider. Its not free, but there are a range of different tools Paul has developed to help you with aspects of suspension setup. They all using Excel underneath – which is quite astonishing IMHO. You do need to be (very) familiar with vehicle dynamics theory and automotive testing techniques to get the most from these tools.
Another option is Chassis Sim. When Danny Nowlan – CEO of Chassis Sim – joined me on the podcast he explained how it unusually uses a “transient” simulation model. That means it has the potential to be more realistic and you can start to tune dampers. There are some novel pricing options for it but unfortunately, there is no way you can try before you buy.
A useful free, pre-packaged racecar lap simulation software is the Optimum G one. This enables you to build up a simple car model and then simulate it lapping around quite a number of race tracks. Claude Rouelle – boss of Optimum G – explained on the podcast that they had had some very good alignment with real data using this simple tool. You will soon find its limitations though as there are very little chassis setup options you can look at. What it does do a good job of as some of the gearing calculations.
Finally, Andrea Quintarelli also discussed how they had adapted a racing game – rFactor – to create a driver-in-the-loop simulator. This approach has a slightly different objective – given your adding the variable of the driver into the equation – but could be an accessible option for you in order to test out your calculations.
Racecar lap simulation software can be extremely useful for understanding and optimising your racecar chassis setup. Unfortunately, the options for the club level racer are very limited. If you have experienced the Professional level simulation software you will know what is possible and what we are missing out on.
If you are looking to start out to build your own lap simulation tool, then the links and resources will give you a great starting point. There is complexity but you can still get useful information from even simple tools.
Best of luck with it. Let me know, if you successfully make an open source transient lap simulation tool!