Vehicle automatically moving forward

Troubleshooting physics
1

So i’m building a driving simulator as a project at university and having a issue with the Ferrari test car provided.

  1. I originally recreated the testfancycar.java file from the controlling a physical vehicle tutorial. Everything worked fine.
  2. I then altered the surface ie what the car drives along (RigidBodyControl) to a simple straight road I created in blender (still using the Ferrari car provided). Everything worked.

3)I then changed the surface again to a more complex model of a city for the car to drive around by only changing this one line (no other lines were changed)-

Spatial city = assetManager.loadModel(“Models/advcity/advcity.j3o”);

I then have an error that the car accelerates automatically without any key input. As soon as the scene loads up the car automatically goes forward.

Any ideas why the car is now automatically moving forward? (even though I only changed the surface model)
Thanks in advance.

2

For anyone else who has this issue, the issue lies with the difference in axis in Blender and JME3. Try rotating the model in Blender so that the y axis points upwards to match the y axis pointing upwards in JME3. Then in JME3 rotate the model back to as desired.

If anyone else has any further information on why this happened for one model, but on the previous model where the z axis was pointing upwards in Blender and there were no issues?

3

As the javadoc of the vehicle states, it works best with z-forward vehicles. Also, blender and jME simply use different coordinate systems but some importers fix this by re-assigning the axes correctly so that you keep “forward, up, right” as in blender. Your issue is probably one combination of these facts.