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I'm building a car sim in Unity3D. I'm trying to set the properties of the car to be as realistic as possible. I can't seem to get a straight answer on Google so I thought of asking here.

What is the typical maximum steering angle of a normal passenger car ?

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You can calculate this based on the properties of the vehicle. Using Ackermann steering geometry you can calculate the center of the turning circle. This will take into account the length and width of the car and simulate accurately the maximum steering radius you can take.

enter image description here

The reason you're unable to find a definitive answer is because it varies from car make to car make. The maximum turning angle of the front wheels depends on the available wheel well space and the hardware involved. You can assume some maximums based on the hardware commonly involved. I would say the wheels wouldn't turn any more than 65 degrees in either direction. That's a pretty high upper bound. However, this is something you can simulate using the model you've created of your car. How far can you turn the wheels before they contact the wheel well?

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    \$\begingroup\$ About 40 degrees. To be honest I was looking for some sort of average of typical steering angles, but I can work with this. thanks. \$\endgroup\$ – Jonny Feb 25 '13 at 22:09
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    \$\begingroup\$ @Jonny Modeling the actual values for the actual car you're using should make it very accurate :) If still want a average of typical steering angles, you'll probably have to ask on an automotive forum. \$\endgroup\$ – MichaelHouse Feb 25 '13 at 22:11
  • \$\begingroup\$ youtube.com/watch?v=i6uBwudwA5o is an excellent explanation about Ackermann steering model \$\endgroup\$ – Rogério Dec Sep 27 '18 at 14:32
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Car manufacturers generally list the turning circle radius, as well as the wheelbase of the car. From there following the diagram above with some simple maths you can calculate back to the approximate steering angle of the inner wheel.

atan(wheelbase / (turning circle - car width)) = angle

For the outer wheel don't subtract the width.

Picking a random car spec sheet look on page 62 - a wheelbase of 2468mm and a turning circle of 10.7m (giving a radius of 5350mm), atan(2468/(5350-1546)) is about 33 degrees.

A more extreme example from this taxi gives 53 degrees.

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The maximum angle of the wheels, when turning, depends on the car's speed and its manufacturing.

More precisely, at higher speed, the steering ratio is smaller when compared to a lower speed, where the steering ratio becomes bigger.

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  • \$\begingroup\$ This is not true. The steering ratio is the ratio between the steering wheel angle and the turn of the wheels: en.wikipedia.org/wiki/Steering_ratio Additionally, the maximum steering angle does not change as your car speeds up... drivers just don't turn as much to avoid flipping the car. However, drifters are very keen on using the full turning range, even at high speeds. \$\endgroup\$ – Marquizzo Sep 12 '17 at 16:55

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