A method of using a drone that is equipped with a camera and an inertial measurement unit (IMU) to survey an environment to reconstruct a 3D map is described. A key frame location is first identified. A first image of the environment is captured by the camera from the key frame location. The drone is then moved away from the key frame location to another location. A second image of the environment is captured from the other location. The drone then returns to the key frame location. The drone may perform additional rounds of scans and returns to the key frame location between each round. By constantly requiring the drone to return to the key frame location, the precise location of the drone may be determined by the acceleration data of the IMU because the location information may be recalibrated each time at the key frame location.