vehicle wrapper - wheel collision issue

Hi everybody!
I noticed that when I use vehicle wrapper to create a simple car game, wheels do not properly detect collision with vertical obstacles (e.g. street curb) - first half of the wheel simply goes through it and only after its bigger part is above the obstacle, the suspension compresses.

It is said that one picture equals thousand words, so I captured two screenshots of what exactly is happening (see the attachment) :wink:

Btw. vehicle in this tutorial appears to face the same problem.

My question is: is there any way to fix it? Some workaround with collision bounds, maybe? I’m making simple game where you navigate big truck through difficult terrain and this doesn’t look very nice… :frowning: I’d appreciate any advice. I’m relatively new to Blender, so there is much I have to learn yet.

P.S. English is not my native language so pls excuse any mistakes i may have made.


Noone knows? I really could use some help… :frowning:

in this case, you can choose convex hull as a collision bound, and the wheels will “slide” over the object. It’s not reallistic, but it’s more credible.

Hi wicinoo,

I noticed the same thing. I ended up placing an invisible ramp in front of each curb. I’ll admit it isn’t the most elegant solution but it’s the best I could think of.


i wanted to say - use convex hull if they are the same object, it will create an invisible “ramp” and the wheels will just slide, if not, do what cthames said. i have the same problem with my scene.


Hi guys, thanks for the replies. Unfortunately, wheels are not the same object (I wouldn’t even know how to do that, I’m using vehicle wrapper and python the way I learnt it from that great tutorial), and adding ramps sounds like “years” of work to me (It’s just guess, though, I didn’t try it). You see, I was planning to build slighltly larger, opened level in desert settings, with all the rocks and cliffs and dunes and stuff… :slight_smile: I worry I would spent most of the time on making these ramps. Isn’t there any other, simpler, solution?

Seeing this is not a mere problem of correct settings, I guess it is a limitation of vehilce wrapper itself, Or am I wrong?

Btw. I would like to know more about GE and how it works. I have experience with various programming languages and techniques, so I’m not scared of Python scripting at all - I just don’t know where to start. If someone could point me to any good study materials, I would really apreciate that. Thanks :wink:

did you try to increase the wheel’s radius in the script?

If you upload the blend, I’ll check it out.

Tire radius won’t make the difference, I’m afraid. It is set correctly for each wheel, that I am sure of.

Anyway, here is the blend. The vehicle model (still under development) is based on ingenious Tatra undercarriage concept (by Hans Ledwinka). One day, I would like to make an offroad truck game out of it. Prepare to be shocked, though - it is an incomplete test version (I use it to try all the stuff I learn about vehicles in GE). I bet modelling is done very ineficiently as well, but give me a break, I’m learning on the go :slight_smile: Also, I had to remove all textures because of forum’s file size limit.


tatraConcept.blend (718 KB)