title: Gimbal Influence on the Stability of Exterior Orientation Parameters of UAV Acquired Images.
abstract: In this paper, results from the analysis of the gimbal impact on the determination of the camera exterior orientation parameters of an Unmanned Aerial Vehicle (UAV) are presented and interpreted. Additionally, a new approach and methodology for testing the influence of gimbals on the exterior orientation parameters of UAV acquired images is presented. The main motive of this study is to examine the possibility of obtaining better geometry and favorable spatial bundles of rays of images in UAV photogrammetric surveying. The subject is a 3-axis brushless gimbal based on a controller board (Storm32). Only two gimbal axes are taken into consideration: roll and pitch axes. Testing was done in a flight simulation, and in indoor and outdoor flight mode, to analyze the Inertial Measurement Unit (IMU) and photogrammetric data. Within these tests the change of the exterior orientation parameters without the use of a gimbal is determined, as well as the potential accuracy of the stabilization with the use of a gimbal. The results show that using a gimbal has huge potential. Significantly, smaller discrepancies between data are noticed when a gimbal is used in flight simulation mode, even four times smaller than in other test modes. In this test the potential accuracy of a low budget gimbal for application in real conditions is determined.
authors.affiliation: Chair of Photogrammetry and Remote Sensing, Faculty of Geodesy, University of Zagreb, Zagreb 10000, Croatia. mgasparovic@geof.hr.
authors.forename: Mateo
authors.initials: M
authors.lastname: Gašparović
authors.affiliation: Chair of Photogrammetry and Remote Sensing, Faculty of Geodesy, University of Zagreb, Zagreb 10000, Croatia. ljurjevic@geof.hr.
authors.forename: Luka
authors.initials: L
authors.lastname: Jurjević
keywords: Inertial Measurement Unit (IMU); Unmanned Aerial Vehicle (UAV); exterior orientation parameters; gimbal; photogrammetry