Disclosed are object detection systems for automated compartment closure assemblies, methods for operating such systems, and motor vehicles with a power liftgate assembly and foreign object detection capabilities. A method is disclosed for detecting objects obstructing the path of an automated closure assembly. The method includes receiving a command signal to move the closure assembly to an open or closed position, and receiving gesture-sensitive sensor signals with a location and velocity of an object within a supervision field. Responsive to the object being inside a protected zone within the supervision field or the object's velocity being towards the protected zone, commanding an automated driving mechanism to: slow the closure assembly's speed; if the object is still located inside the protected zone after a calibrated period of time, stop the closure assembly; and if the object moves outside the protected zone, increase the closure assembly speed to a default speed.