Specialists working in the NASA Jet Propulsion Laboratory have developed the Pulse pendant, which is designed to help reduce the likelihood of coronavirus infection. As you know, there is a risk of infection if a person touches the eyes, nose or mouth with his hand, which previously touched the infected surface. The pendant warns the user with vibration if he notices that he is about to touch his face. The closer the hand is to the face, the stronger the vibrations.
The device includes an infrared proximity sensor, a vibration motor, a switch and a battery. All components are enclosed in a simple plastic case that can be printed on a 3D printer. A file for 3D printing, a list of components with links where you can buy them, assembly instructions – everything you need for making the pendant yourself is on the NASA website.