Method for optical pose detection

摘要

The tracking and compensation of patient motion during a magnetic resonance imaging (MRI) acquisition is an unsolved problem. A self-encoded marker where each feature on the pattern is augmented with a 2-D barcode is provided. Hence, the marker can be tracked even if it is not completely visible in the camera image. Furthermore, it offers considerable advantages over a simple checkerboard marker in terms of processing speed, since it makes the correspondence search of feature points and marker-model coordinates, which are required for the pose estimation, redundant. Significantly improved accuracy is obtained for both phantom experiments and in-vivo experiments with substantial patient motion. In an alternative aspect, a marker having non-coplanar features can be employed to provide improved motion tracking. Such a marker provides depth cues that can be exploited to improve motion tracking. The aspects of non-coplanar patterns and self-encoded patterns can be practiced independently or in combination.

主权项

1. A method for estimating the pose of an object, the method comprising:
disposing a marker on the object; providing two or more optical features on the marker, wherein the optical features are individually recognizable and have fixed positions on the marker, thereby defining a feature pattern having predetermined relative positions of the optical features; imaging part or all of the marker to provide an optical image including one or more of the features as optical imaged features, and determining a pose of the object using the feature pattern as seen in the optical image, in combination with a priori knowledge of the feature pattern.