I did a little "realistic" buggy test, please watch my video (I'm french but I did the video in English).
I just have a little issue, see the python console and my explanation in the video or in the picture below.
The problem is when my ray sensor no longer detects the ground (When car is in mid-air.) It generates an error in the python console and decreases the framerate of my game (especially in full screen). I don't know how to fix this in my script.
This error occurs when my ray detects nothing in its range.
Here's a picture:
Here's the video: https://www.youtube.com/watch?v=fAOVMnYo-ao