Beam Motion Detector Is It Possible To Fool A Motion-sensing Beam?

Is it possible to fool a motion-sensing beam? - beam motion detector

You know what you want "thieves looking for," do not travel with acrobatic skills beam motion detection. Would it be possible for a device, the beams do not recognize in that it is broken construct deceive. What are peoples thoughts? the only criterion is the device must be portable enough to easilly done