How to make the gun in shooting games to move on X and Z axes only?

Hello all,

I'm working on a simulation of a supermarket and has a supermarket cart in it, just like a gun object in unity tutorials, that is a child object of the FPS character. I'd like that object to move only horizontally left and right and go with the character forward and back on the Z axes. Meaning that, while the FPS can look around, I'd like the cart not to be a part of the whole Point of View (as it is with weapon in FPS tutorials), but to act like a cart and "stay" on the ground.

I've tried multi cameras as suggested in Merry Fragmas part 1 tutorial working with levels, but I got two carts in my game view, one is set in place and the other is moving with the character's gaze, when I set the levels and depth, I have only one cart that is moving with the gaze.

How would you approach this issue?

Thanks!

 

add rigidbody, then in rigidbody's constraints, u can freeze certain position or rotation.