Question about collisions

So, in this game I'm working on right now, I've got weapon pickups. You can drop a weapon by pressing Q, and you can pick it up by walking over it.


Anyway, basically I want it to where it acts like a sensor to the player actor but it acts like a normal object when hitting tiles (that is, it doesn't go through walls but the player can walk through it).

Is there any way to do this?

Yes. You need this info: http://www.stencyl.com/help/view/collisions-and-groups/