Each week, our friends at Backerjack bring us updates on some of the most successful gadget crowdfunding campaigns. Jolt Sensor The Jolt Sensor is a small device that lives on an athlete’s helmet, headband, or goggles. It’s white, discrete and hooks up via Bluetooth to smartphones. This smart head protectant is sensitive enough that it can detect when a concussion may have occurred based on the wearer’s head’s acceleration rate.