Creating the Ultimate Adjustable Car Rig


CREATING THE ULTIMATE ADJUSTABLE CAR RIG (UACR).


Oct 10 2020.

Many years ago, I had the idea to make a reusable car rig with suspension capabilities and accurate wheel rotation with regards to steering and translation. The rig could be resized to fit most 4 wheeled vehicles. This rig worked well for everything I needed it for so I put out a car rigging tutorial for this exact rig a few years back that was really well received.


After listening to a ton of amazing feedback and diving deeper into the workings of steering geometry I decided to take this rig to the next level. The growing request list was a bit overwhelming at first but after going through each item individually, it does feel doable and I am pretty excited to work on it.


Here is the main things I will be addressing. I want to thank everyone who contributed to this list, you know who you are 😊.



  • In certain situations the wheels don't rotate accurately.
  • The expression causes some odd viewport glitches for some users.
  • Add Caster,Camber and Toe controls.
  • Adding multiple cars to a scene requires editing the expression on each car.
  • Add Dynamic suspension.
  • Add a steering wheel link up.
  • Add Ackermann & Parallel steering blend option.
  • Automatic steering?
  • I wish the tires would compress.
  • Path animation is tedious and too difficult to setup.
  • Resizing the rig is tricky to do for a beginner in Maya.
  • The model is too simple, it is not usable.



Oct 26 2020.

Here is the new 3D chassis model. The base Sculpt was built with a combination of Autodesk Maya and Zbrush. It consists of over 3million polygons which has been baked down using high end video game techniques in a software called Marmoset toolbag.


Car Chassis 3D Model Bake 1 Car Chassis 3D Model Bake 2

The baked maps are assigned to a final mesh that is constructed from about 200k triangles which is in the same range as a hero car model in a AAA video game. The baking process basically takes the normal tangents from the base Sculpt mesh and transfers them to the final mesh, giving the illusion of more detail where there is in fact none.


Car Chassis 3D Model Bake Wire 1 Car Chassis 3D Model Bake Wire 2



Oct 29 2020.

The chassis needed some color, so taking the baked maps into a pretty neat software called substance painter allowed for a slick result. The best part of this is I can revisit it at any point very easily, so I will leave this where it is for now so I can let the rigging begin.


Car Chassis 3D Model Textured 1 Car Chassis 3D Model Textured 2
Car Chassis 3D Model Textured 4 Car Chassis 3D Model Textured 3

Here is the previous chassis model from the original Adjustable Car Rig (ACR).


Car Chassis Basic

There is quite a difference, and I believe this to be very usable so I can confidently cross this off the list.


  • The model is too simple, it is not usable.



Nov 5 2020.

The first rigging task I wanted to tackle was a well needed replacement for the expression. Expressions are slow and problematic when adding multiple copies of the rig to the scene so I wanted to take the time and rebuild the expression out of utility nodes. Once it was built, I could easily see where I could improve it and manage to reduce the calculations significantly. This new method uses direct interaction with the matrices which has a surprisingly low number of utility nodes so performance is great. So far, no issues with this method but I will keep a close eye on it as it seems too good to be true. 3 major bugs crossed off the list!


  • In certain situations the wheels don't rotate accurately.
  • The expression causes some odd viewport glitches for some users.
  • Adding multiple cars to a scene requires editing the expression on each car.

Here is the UACR driving and steering with the new utility node solution.


Car Chassis 3D Model Rig Steering


Nov 7 2020.

No bugs squashed, but the suspension is in! I have a 9-joint setup per spring that works quite nicely. It is able to compress while accurately keeping the spring volume intact. No curves are used for this; just some well place point weighting so this won’t have any issues exporting to fbx. The CV axle boot motion really adds some life to it. I really want to git those tires deforming next.


Car Chassis 3D Model Rig Suspension


Nov 13 2020.

Tire compression in! Lattices and dynamic solutions are not an option for this because I want this rig to easily be exportable to the fbx format like the previous rig so this left me with 1 method only; do it with joints. The best part of this is you can match any tire model to the correct size and simply copy weights and you are good to go. I will test that theory in more detail at the end. I want to cross this one off the list but I will wait until I get this working with caster + camber before I do so which is my next task. Dang it looks cool though!


Car Chassis 3D Model Rig Tire Pressure


Nov 16 2020.

Camber is in and I was working on caster but then I got distracted with the dynamic Suspension. I set this up using a simple curve with 2 cv’s and a soft-body setup. I hooked it up with body, the tire compression from last week and tossed in automatic camber adjustment for the hell of it. It gives a nice effect and is very delightfully easy to control. A single weight shift object tilts the frame and the soft-body element generates motion to pull it back into place. I suppose it is a pseudo-dynamic setup for now but I think I can hook this into the built-in path system I am working on for a more automated experience.

Car Chassis 3D Model Rig Auto Suspension

I can cross this one off the list, however I may need to tweak it again once it is integrated with the path system.


  • Add Dynamic suspension.