Vehicle Physics

A preview of the new longitudinal wheel dynamics model coming to Vehicle Physics Pro, based on our recently completed internal paper. From three wheel inputs, drive torque (Td), brake torque (Tb), and tire friction (Tf), the model derives the resulting wheel force (F) and torque (T). It also lets computes the net shaft-supported torque Ts. This versatile model produces physically correct behavior across the full range of wheel angular velocity and hub velocity: high speed, low speed, and static equilibrium, with perfectly continuous transitions. Angular inertia and simulation delta time are built in as well, preventing numerical oscillations across the entire input domain. #VPPDev #Unity #TireSimulation #Physics #GamePhysics #MadeWithUnity #Simracing #Engineering

🚗 Build better vehicle feel for the price of a coffee ☕️: EVP is $3.60 on Unity Asset Store for a limited time. assetstore.unity.com/packages/tools… Music: Firing Up by Maniac of Noise — CC BY 4.0 #Unity #AssetStore #Sale #IndieDev #GameDev #Physics #GamePhysics #Simracing #Driving

It’s a Commodore 64! What perfect timing - I was at ZZAP! Live 2026 in Coventry, UK just this weekend, a Commodore fan event 😀

@ddiracing Already available on GitHub 👍: github.com/PERRINN/projec…

@VehiclePhysics Released?

Riders of the kerbs. A beautiful slow-motion view of the new tire contact model in Vehicle Physics Pro. Watch as the tire rides over the top of a kerb, with the contact patch dynamically adapting to the surface. #VPPDev #Unity #MadeWithUnity #Physics #GamePhysics #TireSimulation #Simracing #Motorsport #Racing #PERRINN #Project424 #Engineering

#UnityTips Need to tweak any Project Settings from code? You can! The settings assets in the ProjectSettings folder can be opened as a SerializedObject, so you can read and write their properties directly with SerializedProperty. Details + example code: support.unity.com/hc/en-us/artic… #Unity #IndieDev #GameDev #Coding

Working on DomeProjection integration for PERRINN 424. It enables rendering to triple screens or any multi-monitor setup by just swapping the calibration files, no project rebuild required. #VPPDev #Unity #Simracing #PERRINN #Project424 #IndieDev #GameDev #Coding

@LandfulMinds Yes, but convex sweeps on Unity require a rigidbody on each convex shape, right? AFAIK Unity hasn't exposed sweeps on convex colliders.

@VehiclePhysics I've been studying your posts about wheel colliders, and I found about the sweep convex, which is a thing that i didn't know that PHYSX was capable of Sweep convex :) #indie #indiegame #indiedev

A new update on PERRINN 424 3D model is on the way 😁 #PERRINN #Project424 #DigitalTwins #Motorsport #Engineering

@sean_gause the game looks like this: lots of crunchy plants & nature

#UnityTips Why I recommend using OnEnable / OnDisable for component initialization: Awake and Start are called only once per instance. Disabling/re-enabling the component (or recompiling scripts while in Play Mode) won’t call Awake or Start again. #Unity #IndieDev #GameDev #Coding

@LandfulMinds Looks great! 👏 Is that a SphereCast wheel contact?

Hello everyone, I've been reposting stuff about my wife because she's awesome but It didn't stop me from working on my projects 🙃 @VehiclePhysics I'm sorry mister EVP man, I had to make my own vehicle system 😔 #indie #indiedev #indiegame

@TokyoWarfare Maybe. Still, my main suspect is the downforce calculation inside the PhysX wheel shape. Since gravity is integrated deep in the suspension code, I wouldn’t be surprised if the inertia tensor is involved somehow, too.

@VehiclePhysics Given how careless this was integrated could very well be an unity thing.

Testing the effects of the inertia tensor on vehicle handling using the new Kinematic Wheel Colliders in Vehicle Physics Pro (Unity WheelCollider-free). Turns out the impact is very subtle compared to the legacy wheel colliders, suggesting yet another design flaw in Unity/PhysX WheelColliders. #Unity #Physics #GamePhysics #TireSimulation #Simracing #VPPDev #IndieDev #GameDev

@gateian Yes, that effect also happens in Vehicle Physics Pro. This a longer version of the video, where at the end you can see how the vehicle refuses to turn: youtube.com/watch?v=zmvXzb…

@VehiclePhysics I did a 4x4 day driving course. Of course there is one major problem with diff lock. You can't turn as easily. So with diff lock on, it's always favourable to pick as straight a route as possible.

Open vs. locked differential. A locked differential forces both drive wheels to rotate at the same rate, which can improve traction on slippery terrain. With an open differential, if one wheel loses traction, the available drive torque is limited by that wheel, so both wheels effectively lose tractive capability. #MadeWithUnity #Physics #Simulator #TireSimulation #Showcase #Unity #IndieDev #GameDev #GamePhysics

@DarkoTo56635877 @UnityCodeMonkey What is even less known is that on domain reload (e.g. reimporting an script in runtime) neither Awake nor Start are called, and also all non-serialized fields are reset to null. A correct reference: x.com/VehiclePhysics…

@UnityCodeMonkey What also most Unity beginners don't know is that OnEnable() is called before Start() method. Worth knowing this. Good video btw!

This ONE simple rule helps avoid so many Unity issues!

@UnityCodeMonkey I disagree. That rule won't work on domain reload (for example when you change some code & reload in runtime), as neither Awake nor Start won't be called again, and all non-serialized fields will be reset to null. Here's a proper reference: x.com/VehiclePhysics…

#UnityTips reminder: For the most physically realistic collisions and friction in Unity, use Patch Friction Type + Improved Patch Friction. #Unity #Physics #GamePhysics #GameDev #Unity6 #UnityEngine #IndieDev

This happened to me both in the sim and in real life! 😅🏎💨 Almost lost the rear under braking in a fast corner. #Motorsport #Racing #Simracing #Unity #MadeWithUnity #GameDev #Physics #Simulator