Get current speed of an object

How would I get the current speed of an object? I'm trying to create an AI for an enemy tank, and it can't get over bumps in the terrain. I'm using WheelColliders, and I was wondering if there was a way I could set the speed to higher when it slows down when trying to climb a hill. If there was a way to get the speed, I could compare it. If it was less than ten, I could increase the speed by around 10 or something to get it to climb the hill.

Thanks in advance - Elliot Bonneville

You can check the current velocity from `Rigidbody.velocity`.

From Unity Script Reference:

In most cases you should not modify the velocity directly, as this can result in unrealistic behaviour. Don't set the velocity of an object every physics step, this will lead to unrealistic physics simulation.