TRACMAC BLOG

014 TM0 blog: Part 5

This week we’re talking about how critical it is to keep the mass of a race car as low as possible. While everyone will say “it’s important” being engineers we have to always know just how important it really is. So we made sure to simulate what the resulting lap time would be if we varied nothing else but the mass of the car.

Our results were quite insightful, while it is common for Formula One teams to quote ~0.4sec per lap per 10Kg this number is often thrown around in conjunction with fuel loading. Our results suggested that for our car design the sensitivity of mass on lap time was about 0.25sec per lap per 10kg. It is important to remember that this number will vary from race track to race track and is also dependent on the cars general parameters such as total mass, aero down force, tire grip and engine power. Nevertheless this constant of 0.025sec/lap/kg will be useful in managing efforts to reduce weight and the overall design of the car. Next week I will continue the design review by covering the effect of the vertical placement of center of gravity height (CG) on a race car and its lap time.

Thanks for reading! Until next time,

-Andrew Tolhurst

014 TM0 blog: Part 4

This week’s post is on wheel base. Our simulated results show that there is a minimal change in lap time with changing the cars wheel base. This is most likely due to the weight distribution being held constant while wheel base is varied. In the real world, if we varied the wheel base of the car without changing the layout of the sub systems this would cause the weight distribution to also change. Therefore both should be considered when selecting a wheel base as it was shown in Part 2 of this blog that lap time is extremely sensitive to weight distribution. Generally, a good rule of thumb to keep in mind is the longer the wheel base the more stable the car will be at the trade off to turn in response.

Any reduction of lap time shown in the simulation output would be gains under braking as the longer wheel base would reduce the total amount of weight transfer under acceleration in both the positive and negative directions. Next week I will continue the design review by covering the real effect of extra mass on a race car. 

Thanks for reading! Until next time,

-Andrew Tolhurst

014 TM0 blog: Part 3

This week’s post is on front/rear Track width. As with any simulation it is important to fully understand what assumptions are made, and our simulation is no different. In order to reduce simulation computation time only steady state cornering was considered and transient acceleration/braking. As a result of this the output for lap time vs track width suggests that the wider the track width the quicker the lap time will be. This is however not valid for extremely tight tracks which extremely rapid changes in direction (like auto cross tracks). In this situation the polar moment of inertia increase associated with increasing the track width would also reduce the responsiveness of the car on turn in and hence make the car slower on an overall lap.

However as this car is designed for more open free flowing tracks; this assumption was considered valid and instead of looking at a graph and picking an optimum, other considerations need to be taken into account when selecting the track width. These include:

·         any track width/total width restrictions in any possible racing series the car is likely to compete in,

·         the maximum safe width of a car that can be road registered, and

·         a common width of car trailers as the car may be trailered to a race track.

Whichever of these has the minimum width will be the determining factor of the cars designed track width. Next week I will continue the design review by covering the wheel base simulation results.

Thanks for reading! Until next time,

-Andrew Tolhurst

014 – TM0 blog: Part 2

Over the next few weeks I will be covering some of the simulation results we are using to design some of the fundamental parameters of the TM0. This week’s post is on front/rear weight distribution. Our tyre model simulates the weight sensitivity of the tyres and we intended to develop a more refined tyre model once we have a prototype on track to use as a test bed and measure actual forces on. This will give us the ability to validate our simulation and make tuning/design changes more efficient.

Our understanding of the results shown is: up unit a point (shown to be ~43%) the gains of increased braking performance on this particular race track outweighs the loss of ultimate cornering grip (assuming same tyres are used front and rear). However once you pass this optimum point the loss of cornering acceleration overcomes any gains in braking performance. I would also like to point out that the data shown is the output from our own simulation software developed in house and is only valid for the particular design parameters that are unique to our design for the TM0 at the race track simulated. Next week I will continue the design with track width. While we are completing this project join us by sharing what car you like to take to the race track.

Thanks for reading! Until next time,

-Andrew Tolhurst 

Project: 014 – TM0 blog

Hello world! This is my story: In the pursuit of lateral acceleration and the thrill of driving…

For as long as I can remember I have been a fan of motorsport and since my days in school I have been sketching cars and race tracks. So now that I run my own engineering company I guess it’s the best time to finally tackle a project as big as a high performance car designed and built by drivers, for drivers. So I hope you enjoy reading about our project: The TM0, a real driver’s car!

Read More

Tracmac Blog Launched

Welcome to the new Tracmac Blog. Here we will show you upcoming products and examples of some of the great products we have been working on along with things you may find interesting.

Read More

(Source: tracmac.com.au)