Car keep moving when wheel collider motor torque zero

Car still moving when motor = 0

Code (CSharp):

1. public void FixedUpdate()
2.     {
3.         foreach (AxleInfo axleInfo in axleInfos)
4.         {
5.             if (axleInfo.steering)
6.             {
7.                 axleInfo.leftWheel.steerAngle = steering;
8.                 axleInfo.rightWheel.steerAngle = steering;
9.             }
10.             if (axleInfo.motor)
11.             {
12.                 axleInfo.leftWheel.motorTorque = motor;
13.                 axleInfo.rightWheel.motorTorque = motor;
14.  
15.                
16.             }
17.            
18.             if(motor==0)
19.             {
20.                 axleInfo.leftWheelAnimator.speed = 0;
21.                 axleInfo.rightWheelAnimator.speed = 0;              
22.             }
23.             else
24.             {
25.                 axleInfo.leftWheelAnimator.speed = 1;
26.                 axleInfo.rightWheelAnimator.speed = 1;
27.             }          
28.         }
29.     }  

 

Can't see anything wrong...

 

Shouldn't the tank stop moving in few secs when motortorque zero( track animation stop)? It keeps moving forever. I also find similar problem in the car sample scene, the car "slide" very long distance after motor torque become zero.

 

I think I solve the sliding problem by adding infinity brake torque. (very high brake torque do not work)

But I find a new problem now, the acceleration is awful. Motor torque do not increase the tank velocity, and wheel rpm is read only. How can i accelerate it?

Code (CSharp):

1.  if (motor == 0)
2.                 {
3.                     axleInfo.leftWheel.brakeTorque = Mathf.Infinity;
4.                     axleInfo.rightWheel.brakeTorque = Mathf.Infinity;
5.                 }
6.                 else
7.                 {
8.                     axleInfo.leftWheel.brakeTorque = 0;
9.                     axleInfo.rightWheel.brakeTorque = 0;
10.                 }