3d check ahead of the object

there is a task - there is a conveyor in a 3d game - resources move along the conveyor - the question is how to make the resources stop if there is already a resource in front of them - I need some kind of raycast check, but I can’t configure raycsat to work on all copies of objects - I tried to use the distance to the object, but it also checks around in all directions - using 3D physics is not an option - any ideas?