AddForce() causing objects to intersect for one frame

I made a simple project to test different ways of moving rigid bodies and found some odd results:

I have a cube that the player can move around with a Box Collider and a Rigid Body, set to Continuous Dynamic.
I have a wall that has only a Box Collider on it.

My movement code uses this in the fixed update:
m_RigidBody.AddForce(m_m3Velocity * Time.fixedDeltaTime, ForceMode.Impulse);

When I move the cube at high speed, it visibly penetrates half way into the wall for one frame before being pushed back. I can pause Unity just before the moment of impact and step forward frame by frame and actually catch the frame where it intersects.

My understanding was that using AddForce() with a Continuous Dynamic rigid body should not penetrate at all: it uses swept collision doesn't it and should resolve the penetration before rendering.
How do you prevent this bug?

 

With further testing, I can reproduce this most accurately using this code in the fixed update:

Code (CSharp):

1. Vector3 currentVelocity = m_RigidBody.velocity;
2. currentVelocity.x = 30;
3. m_RigidBody.velocity = currentVelocity;

Using the editors Pause and Step buttons, I can freeze it on the frame where a 1m cube penetrates to half its depth for one frame before being pushed back out.

 

Seeing the same results. Confused by this as well.

 

But OP stated he is using continuous collision detection

 

Well, I meant to imply that I am using the same settings by saying that I am seeing the same results. There is a frame of intersection, and I'm using continuous collision detection against a static collider.

 

With further testing, it seems like continuous collision detection prevents the rigidbody from going THROUGH the other collider, but it doesn't prevent it from going INSIDE (afterwards the physics engine depenetration pulls it back out over several frames). Weird stuff.

So apparently "PhysX3 features an algorithm used to detect whether the expensive CCD simulation is actually needed given the current body velocity or a default discreet would do just fine. It’s activated once you enable the CCD."

Which is extremely annoying because this means discrete collision detection is activated at lower speeds that allow objects to interpenetrate...

@MelvMay Can you give us an option to disable this algorithm?