We want to exploit sunlight to allow objects to communicate information. Communication with light can be achieved by turning the light source ‘on’ and ‘off’ (like with a flashlight), but we cannot turn the sun ‘on/off’.

Our goal is to enable objects to exploit light sources, such as the sun, to transmit information in a sustainable (no batteries) and privacy-preserving manner (no cameras).

Since we cannot control the sun, we propose to exploit smart surfaces to convey information. Objects will sense data, but instead of communicating this information with a radio module they will adapt the reflective properties of their external surfaces according to the information they want to convey (like a chameleon). We want to cover objects with a new generation of smart materials that are able to change their reflectivity such as smart windows & clothes. The changes in reflection will modulate (turn on/off) light. Then, photoreceptors deployed in our environments will decode the reflected signals. This system could be seen as a barcode reader but to track and sense objects in our cities and buildings with zero energy costs.