Slow Vehicle Acceleration

Hi,

In PhysX 3.4, I’m trying to develop a 4-wheeled vehicle (Humvee) with differential type LS_4WD. The problem is that vehicle accelerates very slowly at first launch and when the RPM builds up it moves normally. The vehicle fails to take off even in very low inclines. I tried everything and it is not working. Do you have any ideas?

Thanks in advance.

I’m not an expert by any means but I’ve run into similar issues in the past - and if I remember correctly a lot of them were caused by joints not allowing full rotation, and sometimes inter collisions.

A good way to test if the vehicle’s wheels are not getting stuck on anything is to make a debug drag script that lets you drag the vehicle forward, if the wheels are spinning freely then the problem lies somewhere else.

Slow acceleration was like you said related to wheel collisions. I fixed it, but now vehicle won’t move on even slight inclines.

I fixed not climbing slopes from rest issue. I set the RPM of engine manually on launch and the vehicle perfectly climbs reasonably slopes. I think the vehicle struggles to gain RPM when at rest. I tried setting up with massive torque values, but it did not make any difference. NVIDIA has to implement idle RPM mechanics…