Dr. Johannes Heidenhain Gmbh

Franz Langrieger

Markus Meissner

Siegfried Reichhuber

Nikolas Tekles

Stefan Gilg

Alexander Schwanecke

A method for tracking a retroreflector that is movable in space includes emitting a measurement light beam toward the retroreflector. A tracking control signal is generated as a function of the position of the measurement light beam reflected by the retroreflector on a detector. A status determination is continuously made as to whether the measurement light beam is steerable to follow the retroreflector or whether the retroreflector has been lost. In a search mode based on it having been determined that the retroreflector has been lost, a trajectory estimation is performed based on measurement values to determine an estimated trajectory. A search pattern adapted to the estimated trajectory is created, and the measurement light beam is then moved along a corresponding search path using tracking control signals derived from the estimated trajectory and the search pattern. The search mode is terminated upon a tracking control signal being generatable again.

Method for tracking a retroreflector and device for carrying out such a method

A sensor assembly for measuring a torsion of a rotor blade of a wind turbine generator system includes a first light source configured to generate light and a first transmitter-side polarizer disposed downstream thereof in a direction of light propagation and configured to generate linearly polarized light as a first transmission light. A second light source is configured to generate unpolarized light as a second transmission light. First and second detector elements are arranged and adapted to receive the first and second transmission light. A first receiver-side polarizer is disposed upstream of the first detector element in the direction of light propagation and a second receiver-side polarizer is disposed upstream of the second detector element in the direction of light propagation. An orientation of a polarization plane of the first receiver-side polarizer and an orientation of a polarization plane of the second receiver-side polarizer are different from one another.

Growing community of inventors

Trostberg, Germany

Franz Langrieger