Strange Car Behavior

Unity Engine
1

Hello Unity People,
I playing with some vehicle stuff and created a rig based the tutorial from http://www.gotow.net/andrew/blog/?page_id=78

But my car is acting weird… Everything except some friction data is same the tutorial. I still cant understand the reason of that weird behavior… :frowning:

Have to define weirdness in this case…
-First of all, it have 5 gear but not even can accelerate enough for gear up or something…This is main problem.
-When i want to turn, it start accelerating but loose the grip and flies around.
-I had to multiply with -1 to inputs because when i press up arrow it was going backwards instead forward… Like :

FrontLeftWheel.motorTorque = EngineTorque / GearRatio[CurrentGear] * Input.GetAxis("Vertical") *-1;
	FrontRightWheel.motorTorque = EngineTorque / GearRatio[CurrentGear] * Input.GetAxis("Vertical")*-1;

Is any experienced fellow can help me to find the problem?

You can see the web version from http://www.unitstudios.com/unity3d/carrig.html
and can download the project from http://www.unitstudios.com/unity3d/Unity3d_Car_RiggingProject.zip (11MB)

Thanks for help!

2

Some ideas for you to check.

Checkout your torque value and your gears ratio. Lower gears should have higher ratios to accelerate faster. And the torque of the motor defines the “strength” (so to speak) of the motor.

Checkout the stiffness and friction values of the wheel colliders, as well as the physics material of the floor. Also, make sure the engine torque is not too high compared with the mass of the car.

Check the Input Manager and make sure the “Vertical” input (there could be more than one) has the up arrow as its positive value, and not the negative.

I’ve tried the tutorial and it ran fine to me.
Hope some of this helps!

3

Thanks for tips…
I didn’t change physical material of floor. Just added terrain… But it was no any other physics material example project too. Shall i edit that?

my gear rations are

   * 1st Gear : 4.31 : 1.0
    * 2nd Gear : 2.71 : 1.0
    * 3rd Gear : 1.88 : 1.0
    * 4th Gear : 1.41 : 1.0
    * 5th Gear : 1.13 : 1.0
    * 6th Gear : 0.93 : 1.0

same as the example project. But indeed have to check torque… Cant remember exact value but it must 500 around. I’ll check that evening. But increased stiffness values from fricton because when i make that 0.092 in sample it was sliding on the terrain… So i increased to 0.5…

Didnt know the input manager trick. Will check.
Thanks mate.