I am working on project which includes usage of vehicles. Since the beginning I am experiencing problem with vehicle setup. I have identified this issue to be caused by offset of wheel collision meshes which are assigned to objects of type VehicleWheel. Using pxvis collision shows this:
In UE4.10 i have set up WheeledVehicle BP, It’s wheels (class, bone names, no offsets). Bone names match those in Skeletal Mesh. Vehicle does work normally, wheels rotate and steer. Same blueprint setup works for different Skeletal Meshes, where collision meshes match the bone positions.
I am using custom mesh which i downloaded and modified in 3DS Max 2013 (Student version). I believe this to be the cause of problems. Since I am beginner in 3D modeling i might have made some mistakes regarding transforms etc.
Structure
My model has no bones, i have vehicle chassis (single object) as parent of 4 wheels (5 objects total).
Scale
Since i did scaling of the objects i applied xform reset on all objects as it was repeatedly mentioned in answers provided by community, however it didn’t resolve anything (all objects have now 100 scale).
Pivots
Chassis pivot point is set to (0, 0, 0).
Wheels have their pivot in their center.
Export and Import
I used several export/Import options. Did not help.
You must use Reset XForm in 3DS MAX before export your model. Unparent Wheels. Then select Base and Wheels and apply Reset XForm. Convert all meshes in an Editable Mesh. Parent the wheels to the base. Export the model to FBX. In export dialog, change FBX version to 2014/2015.
HI,
thanks for your response. I believe i already did XForm reset and converted to Editable Mesh. Nevertheless, i tried it again and there were no improvements. It is possible I am doing it wrong. What import options did you use? Could you send your FBX, which you used in picture above? I think it would help me a lot.
Thanks for your time VB.
your FBX works like a charm. Still there are few things i dont realy understand. When i open your export in 3DS max i see that the scale of Vehicle_Base is 39,37%. Scale of each wheel is 100%.
In my export Vehicle_Base was 100% same as wheels, which i understand is the way it should be? This makes me suspect some kind of bug within my 3DS, because i made XForm reset several times. I assume that you see vehicle_base as 100% scale yourself?
I have even tried simplified model: box with 4 cylinders as wheels. I did no scaling on any of the objects. Still, after export/import i experienced same thing.
Thanks again, VB.
Hello,
I found the problem, but didn’t solve it. I am almost certain that it was caused by some scaling issue within 3ds Max. I think it’s bug, because my 3ds max shows chassis at 100 scale but it behaves like it was overscaled, therefore wheels are inset. When I opened fixed FBX from svv3dUDN i noticed chassis was at 39.37 scale, yet strangely it was correct size. I suspect some strange settings or even bugs within 3ds Max. Iam quite sure this issue has nothing to do with UE4.
Regards VB
So the solution you are using is just to manually offset the weel in the vehicle movement component?
If yes did you get any bug after using that trick as a solution?
Thank you,
Mike
