Abstract
The output signals of inertial sensors and a camera are used to realise a pen-like human-computer interface with six degrees of freedom. The pen-like interface works over planar, structured surfaces. The pose estimation with a monocular camera has a high uncertainty on the rotation if the surface is unknown and no pre-known markers are used. A hybrid pose estimation method is used to improve accuracy. From output signals of three orthogonally placed accelerometers the absolute 2D tilt of the pen-like interface with respect to the gravitational field is calculated. This 2D rotation information is used to improve the robustness of the pose estimation using a modified homography calculation. Utilising three-dimensional detection of the pen’s pose several applications are possible, e.g. ergonomic humancomputer interfaces in 6D, image mosaicing applications or devices for handwriting input.