Former NASA engineer Mark Rober spent the past 3-years creating a robotic dartboard that almost guarantees a bullseye every throw, or at least if the conditions are met. His creation consists of a Vicon motion capture system with 6-cameras that track the dart using infrared LEDs and darts equipped with retro-reflectors attached, which are used determine its exact location in 3D space. The trajectory of the dart can be then calculated with physics to predict where it will hit with extreme accuracy. The dartboard itself is attached to two sliders with a system of six stepper motors to maneuver it around. Once the motion tracking system calculates the bullseye location, a computer then transmits instructions to move the board, and all of this happens in milliseconds. Click here to view the first image in today’s viral picture gallery. Continue reading for the five most popular viral videos today, including one of the world’s simplest electric train.