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Custom Vehicle wheels are not moving and not colliding with floors

Hi, this is Eta, I am making a vehicle using wheelvehicles blueprint by following the documents https://docs.unrealengine.com/latest/INT/Engine/Physics/Vehicles/VehicleUserGuide/ However, my wheels do not collide with the floor but fall in, and my car cannot move or rotate
I have rotate the vehicle direction to right to match the ones in the official examples, and the animBP is working with wheels handler that made wheels fall down from their original position, but the wheels are just not colliding with the floor, and I checked the collision was smaller than the physic asset while simulating, though how editing it just cannot work.
Could someone help me out with this?
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Thank you so much.

The last time I checked, the UE4 wheeled vehicle class does NOT use the collision object of the wheel for vehicle movement. Instead it uses ray casting and the wheel radius you specify in the wheel class.

Vehicle BP > VehicleMovement Component > Vehicle setup > Wheel Class

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Just a guess.

Hi, thanks for the reply Quaternion, actually I tried this before but it doesnot work, no matter what size it was and how big the offset is, I even changed it to 5000 but it still not working, I think it might be the problem that the car wheels cannot be found. However, the wheels collision cannot be shown though collision display was on.

Are you sure your bones are properly set up? Wheels collision not being where it should is usually caused by wrong bones…

Hi, Zireael07, thanks for the reply, Actually, our car was rigged similarly to the official sedan vehicle, the root bone was at the lowest central point, and the pivot is at (0,0,0)

@TKEta, in this picture

&d=1482790968 the red arrows on the wheel bones are pointing down and the blue seems to be pointing towards me. It tells me your wheel bones are wrongly rotated (X up and Z forwards). You need to fix the wheel bones so that Z is up and X is forwards.

Hi Zireael07, thank you for your respond, I am going to change it immediately and see whether it can be fixed, I will reply to you soon!

I checked the FBX you attached. Zireael07 was right. It’s not what UE4 expects. Here is a simple vehicle project with your mesh.

https://drive.google.com/open?id=0B4zooWDjDyoXcGg2U0dwYXZjams

The FBX was done with 3dsmax. I have no idea how to do bones or hierarchies in other modeling apps.

Hi Quaternion, I just saw your project? How did you rigged it? It was so perfect!!!Thank you so much!

Hi Zireael07, we rerigged the vehicle and the wheels do have the collision right now, however, when it was moving, the car will move to left side not forward, each one of the front wheel and back wheel on the right side will move instead of the two front wheels:
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So this sides of wheels will move
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I went through this same thing a long time ago but haven’t looked for awhile so no specifics (sorry).

You need to show your wheel wireframes (I forgot how to do that part).

You’ll find all four of your wheels are stacked right under the middle of your vehicle. That’s why it’s tipping off center like that.

You’ll need to adjust each wheels positioning to the proper place. (left wheel= forward and to the left, etc…)

In 3dsmax you can attach one object (mesh) to another in hierarchies - no bones needed. This seems to work well for me when I use the Wheeled Vehicle Class. This is my hierarchy for the meshes in 3dsmax:

Vehicle_Base
-Wheel_Front_Left
-Wheel_Rear_Left
-Wheel_Front_Right
-Wheel_Rear_Right

All 4 wheels are attached to the Vehicle Base in Max. This matches what is used in the UE4 vehicle sample project.

What modeling software are you using?

@Quaternion @jay_adams_11 @Zireael07 .Thank you guys I did it! Thank you for all your help! By the way, do you know how can I rotate the AI vehicle towards the target point? In blueprint way

Search for “Peter L. Newton” in these forums.

Look at the thread: [UPDATED 5/16] A.I. Templates - Bot, Car, & +Flying AI

Hi, I just saw the link but it doesn’t have anything about rotating the car, it is just a simple preview without specific demonstration on the rotation. Do you know the specific node in blueprint I can use?