Hannes Ovren

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We propose a technique for joint calibration of a wide-angle rolling shutter camera (e.g. a GoPro) and an externally mounted gyroscope. The calibrated parameters are time scaling and offset, relative pose between gyroscope and camera, and gyroscope bias. The parameters are found using non-linear least squares minimisation using the symmetric transfer error(More)
In this paper we introduce an efficient method to unwrap multi-frequency phase estimates for time-of-flight ranging. The algorithm generates multiple depth hypotheses and uses a spatial kernel density estimate (KDE) to rank them. The confidence produced by the KDE is also an effective means to detect outliers. We also introduce a new closed-form expression(More)
In recent years several depth cameras have emerged on the consumer market, creating many interesting possibilities for both professional and recreational usage. One example of such a camera is the Microsoft Kinect sensor originally used with the Microsoft Xbox 360 game console. In this master thesis a system is presented that utilizes this device in order(More)
High resolution 3D images are of high interest in military operations, where data can be used to classify and identify targets. The Swedish defence research agency (FOI) is interested in the latest research and technologies in this area. A drawback with normal 3D-laser systems are the lack of high resolution for long range measurements. One technique for(More)
Modern day cars are often equipped with a vision system that collects information about the car and its surroundings. Camera calibration is extremely important in order to maintain high accuracy in an automotive safety applications. The cameras are calibrated offline in the factory, however the mounting of the camera may change slowly over time. If the(More)
Simultaneous localization and mapping (SLAM) is the problem of mapping your surroundings while simultaneously localizing yourself in the map. It is an important and active area of research for robotics. In this master thesis two approaches are attempted to reduce the drift which appears over time in SLAM algorithms. The first approach tries 3 different(More)
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