Visual Cryptography for Detecting Hidden Targets by Small-Scale Robots

The last few years have seen a growing use of robots to replace humans in dangerous activities, such as inspections, border control, and military operations. In some application areas, as the latter, there is the need to hide strategic information, such as acquired data or relevant positions. This paper presents a vision based system to find encrypted targets in unknown environments by using small-scale robots and visual cryptography. The robots acquire a scene by a standard RGB camera and use a visual cryptography based technique to encrypt the data. The latter is subsequently sent to a server whose purpose is to decrypt and analyse it for searching target objects or tactic positions. To show the effectiveness of the proposed system, the experiments were performed by using two robots, i.e., a small-scale rover in indoor environments and a small-scale Unmanned Aerial Vehicle (UAV) in outdoor environments. Since the current literature does not contain other approaches comparable with that we propose, the obtained remarkable results and the proposed method can be considered as baseline in the area of encrypted target search by small-scale robots.