GPS and IMU Replacement Using Stereovision in Small Unmanned Aerial Vehicles GPS is not effective indoors, and measuring systems like LiDAR are too big to be used on some small Unmanned Aerial Systems (sUAS) according to the developers of the Centeye (Barrows, 2016, 0:01-0:28). The idea of the Centeye is to use two light cameras for stereo vision on all four sides of the quadcopter to create a full 360ยบ field of view on which measurements of objects can be made (Centeye, n.d.a). The cameras used on the visual system are less than a 1cm (0.4in) long and weight less than 0.2 grams (0.000441lbs), so they can be installed on Nano quadcopters weighting in at 38 grams (0.0838lbs) (Centeye, n.d.a). While the small format CMOS sensor (Centeye RockCreek™ vision chips) is the heart of the Centeye, the whole sensor is made up of two of the trademark light sen...