While the western (and especially nordic countries) social etiquette already marks an unwritten physical distancing between unkown people interacting as being the length of the hand, the context of the Covid days points this type of approach as a global must, either in exterior or inside spaces where groups of people interact. But the correct physical distance from our fellows, in order to stay safe from the virus, is quite a provoking and hard to control thing to manage.
A solution that signals the optimal safe distance from the people you're phisically interacting with, without being forced to stay completely socially distanced from the rest of the community.
SPS (Safe Proximity Sensor) works as a signal gadget which informs you about the optimal distance between you and your fellow ones, in order to enhance protection by the possible risk of taking a virus. It works as an analogy from the cars object sensor detectors and can be either an add on for existing accessories, such as phone, headphones, or as a stand alone accessory, either as bracelet, or a necklace. Developed technology related to the idea: https://www.youtube.com/watch?v=xWJFBMBlVPA