Collections > UNC Chapel Hill Undergraduate Honors Theses Collection > An IMU-Enabled Camera Rig for Wide-Range Stereo Videography in the Field
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In stereo videography, two or more cameras are used to film the same scene from different positions, and then the information from those camera views is combined to reconstruct the 3D positions of objects in the scene. Previous stereo videography set-ups in biomechanics research have required that the cameras remain fixed and stationary throughout the duration of filming. We built a rig with two GoPro cameras mounted on a rotatable tripod that can be used to film in the field. Our rig can be rotated to follow animals or other moving objects in the scene and can record from a wide spatial area at better resolutions than previous set-ups. An inertial measurement unit (IMU) mounted on the rig records acceleration, magnetic field, and angular velocity. We use a Kalman filter to fuse data from these inertial sensors to determine orientation of the rig at every frame during video recordings. Using these orientations, we then transform 3D points from each frame onto a single set of global coordinates. Our rig enables us to rotate our cameras to film a wide area, and then remove that rotation from 3D information extracted from the video, giving us the 3D points a stationary observer would have seen.