How to make a curved platform for a 2d racing game?

I want to make a platform for a racing game , like the following attachment.

But in physics engine, when I set its shape as a box and procced, the vehicle travels on the box shaped sprite.

I don’t want to use rectangle sprites as the platform. And also editing the collision mask also didn’t help, as the physics engine uses a separate collision mask( I think so ).

Any ideas??

In the Physics2 settings, change the object’s shape type to “Edge”:


and then modify the object’s physics collision shape.