In the field of physical augmentation, researchers have attempted to extend human capabilities by expanding the number of human appendages. To fully realize the potential of having an additional appendage, supernumerary appendages should be independently controllable without interfering with the functionality of existing appendages. Herein, we propose a novel approach for controlling supernumerary appendages by exploiting upper limb redundancy. We present a headphone-style visual sensing device and a recognition system to estimate shoulder movement. Through a set of user experiments, we evaluate the feasibility of our system and reveal the potential of independent control using upper limb redundancy. Our results indicate that participants are able to intentionally give commands through their shoulder motions. Finally, we demonstrate the wide range of supernumerary appendage control applications that our novel approach enables and discuss future prospects for our work.