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Hahn, Hernsoo

Publications and source records attributed to Hahn, Hernsoo.

Distributed Optoelectronic Proximity Sensor

Optoelectronic proximity sensor comprises seven identical units functioning together to provide partially redundant data on spatial relationship between sensor and nearby diffusely reflecting surface. Provides data on distance, relative orientation, and curvature of surface. Sensor called "Hexeye" because its units exhibit hexagonal symmetry when viewed along optical axes and mounted together in hexagonal close packing. Because all six arrays of photodetectors in unit measure essentially identical distributions of light in operating mode, each provides redundant information averaged to increase accuracy or used to verify operation of others. Malfunctioning photodector identified, and output ignored or replaced by interpolated value. Developed for use in such robotic applications as noncontact probing or scanning of surfaces, localization and recognition of objects, and guiding "smart" robot hands in grasping objects.

Lee, Sukhan

An optimal sensing strategy for recognition and localization of 3-D natural quadric objects

An optimal sensing strategy for an optical proximity sensor system engaged in the recognition and localization of 3-D natural quadric objects is presented. The optimal sensing strategy consists of the selection of an optimal beam orientation and the determination of an optimal probing plane that compose an optimal data collection operation known as an optimal probing. The decision of an optimal probing is based on the measure of discrimination power of a cluster of surfaces on a multiple interpretation image (MII), where the measure of discrimination power is defined in terms of a utility function computing the expected number of interpretations that can be pruned out by a probing. An object representation suitable for active sensing based on a surface description vector (SDV) distribution graph and hierarchical tables is presented. Experimental results are shown.

Lee, Sukhan