Dr. Johannes Heidenhain Gmbh

Johannes Heidenhain Gmbh

Markus Meissner

Wolfgang Holzapfel

Johann Mitterreiter

Joerg Drescher

Ralph Joerger

Bernhard Musch

Thomas Kaelberer

Jörg Drescher

Erwin Spanner

Franz Langrieger

Siegfried Reichhuber

Michael Stepputat

Robert Kraus

Robert Sturm

Alexander Schwanecke

Thomas Kälberer

Nikolas Tekles

Stefan Gilg

Robert Metzke

Robert Kellner

Ralf Bihr

Bernhard Pletschacher

Manuuel Scherer

Stefan Birnbacher

Markus Eberl

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.

Sensor assembly for measuring at least a first torsion of a rotor blade of a wind turbine generator system

An interferometric distance measurement device includes a multiple wavelength light source, supplying a light beam having at least three different wavelengths. An interferometer unit is provided, which splits the light beam into a measuring light beam and a reference light beam. The measuring and reference light beams reflected back by measuring and reference reflectors are superimposed in an interfering manner to form an interference light beam. The interference light beam is split via a detection unit such that, in each instance, a plurality of phase-shifted, partial interference signals result per wavelength. With the aid of a signal processing unit, an absolute position information item regarding the measuring reflector is determined from the partial interference signals of different wavelengths.

Device for interferometric distance measurement

An X-Y table with a position-measuring device includes a table which is disposed on a support and is movable on the support so that altogether the table is positionable in a plane parallel to an underlying stationary base. Two groups of scanning heads are disposed on the support. For position measurement in two directions, a respective one of the scanning heads directs light through a respective transmissive scale attached along an edge of the table such that a respective reflective scale, which is stationary relative to a processing tool disposed above the table, reflects the light through the respective transmissive scale back to the respective scanning head. In a central position of the table, the two groups are in positional correspondence with the transmissive scales, and, in either of two edge positions of the table, only one of the two groups is in positional correspondence with the transmissive scales.

X-Y table with a position-measuring device

A machine tool includes a stationary machine frame, a tool head, which is able to be positioned relative to the machine frame along three mutually orthogonal translation axes, and a motor-driven tool. The machine tool includes a swivel unit, which can be pivoted about a horizontal swivel axis relative to the machine frame and includes a workpiece positioning device, via which a workpiece can be rotated about an axis of rotation oriented perpendicularly to the swivel axis. The swivel unit is assigned a measuring frame, which is able to be rotated with the swivel unit and is arranged to be thermally and/or mechanically decoupled from the swivel unit and includes components of a first and second position measuring system. Additional components of the first position measuring system are disposed on the tool head, and further components of the second position measuring system are situated on the workpiece positioning device. The spatial position of the tool head in relation to the measuring frame is ascertained via the first position measuring system, and the spatial position of the workpiece positioning device in relation to the measuring frame takes place via the second position measuring system.

Machine tool

An interferometer includes a light source, a beam splitter, a reference reflector, a measuring reflector, a detection unit, and at least two transparent plane-parallel plates. The beam splitter splits a beam of rays into at least one measuring beam and at least one reference beam. Until being recombined, the measuring beam propagates in a measuring arm, and the reference beam propagates in a reference arm. The reference beam falls at least three times on the reference reflector located in the reference arm. The measuring reflector is disposed in the measuring arm and is joined to an object to be measured, which is movable along a measuring direction relative to the reference reflector. The measuring beam falls at least three times on the measuring reflector. At least one distance signal with regard to the position of the object to be measured is ascertainable from the interfering measuring and reference beams via the detection unit. The plane-parallel plates are disposed parallel to each other in the beam path between the light source and the detection unit. At least the measuring reflector is movable relative to the plane-parallel plates along the measuring direction. The plane-parallel plates each include a plurality of optical elements that exert such an optical effect on the measuring beam and the reference beam that they propagate parallel to each other in the direction of the measuring reflector and reference reflector, respectively.

Interferometer having two transparent plates in parallel for making reference and measurement beams parallel

In an optical position measuring device for detecting the relative position of a first measuring standard and a second measuring standard, movable relative to each other along at least one measuring direction, at a splitting grating, a beam bundle emitted by a light source is split up into at least two partial beam bundles. When passing through scanning beam paths, the partial beam bundles undergo different polarization-optical effects. After the differently polarized partial beam bundles are recombined at a combination grating, a plurality of phase-displaced, displacement-dependent scanning signals is able to be generated from the resulting beam bundle. No polarization-optical components are arranged in the scanning beam paths of the partial beam bundles between the splitting and recombination. To generate the different polarization-optical effects on the partial beam bundles, a conically incident illumination beam bundle impinges upon the splitting grating, the incident illumination beam bundle extending in a plane perpendicular to the measuring direction at an angle other than 0&#xb0;, the plane of incidence being defined by the grating normal to the splitting grating and the direction of incidence of the illumination beam bundle. The scanning beam paths of the partial beam bundles are arranged in mirror symmetry with respect to the plane of incidence between the splitting and recombination.

Optical position measuring device

An interferential position-measuring device determines a position of an object which is disposed to be movable along a measurement direction. A light source is configured to emit a beam which is split into two sub-beams. One of the sub-beams impinges on an optical functional element on the object. The sub-beams are subsequently superimposed and interfered at a superposition location and a resulting signal beam propagates toward an evaluation unit configured to generate a position-dependent measurement signal from the resulting signal beam. A switching element is disposed in the signal path downstream of the superposition location and upstream of a signal-digitizing device. The switching element is configured to define a specific sampling point in time.

Interferential position-measuring device and method for operating an interferential position-measuring device

An optical position-measuring device includes a measuring standard as well as a scanning unit movable relative to it along at least one measuring direction, a scanning beam path being formed between the measuring standard and scanning unit and being used to generate displacement-dependent signals. A protective cap is disposed in a manner allowing movement along an axis perpendicular to the measuring-standard plane such that in at least one operating mode, the protective cap for the most part surrounds the scanning beam path between the scanning unit and measuring standard.

Optical position-measuring device

A position-measuring device for detecting the position of two objects movable relative to each other, includes a measuring standard that is joined to one of the two objects, as well as a scanning system for scanning the measuring standard, the scanning system being joined to the other of the two objects. The scanning system permits a simultaneous determination of position along a first lateral shift direction and along a vertical shift direction of the objects. To that end, on the part of the scanning system, two scanning beam paths are formed, in which a group of phase-shifted signals is able to be generated in each case at the output end from interfering partial beams of rays. In addition, via the scanning system, at least a third scanning beam path is formed, by which it is possible to determine position along a second lateral shift direction of the objects. The beam from a light source is able to be supplied to the scanning system via a first light guide and coupling-in optics in common for all three scanning beam paths. The interfering partial beams of rays produced in the three scanning beam paths are able to be coupled via common coupling-out optics, into a second light guide which supplies these beams of rays to a detector system.

An optical position measuring instrument including a first scale having a first graduation, wherein the first scale is disposed movable in a first measuring direction, and at a first defined position in the first measuring direction, the first scale includes a spatially limited first marking that differs from the first graduation. The optical position measuring instrument further including a second scale having a second graduation, wherein the second scale is disposed movable in a second measuring direction, and at a second defined position, the second scale includes a second reference marking that is usable for generating at least one reference signal at a reference position of the second scale only if the first scale is located in the first defined position.

Optical position measuring instrument

A position-measuring device, as well as a system having such a position-measuring device, is used for determining the position of a first object relative to a second object, the first and the second object being movable relative to one another along at least two measuring directions. The position-measuring device has an optical unit that is linked to one of the two objects and includes at least one light source, a detector system, as well as further optical elements in a defined configuration. In addition, the position-measuring device includes a measuring standard-reflector unit, which is provided on the other object, and has at least two differently formed regions in one track that are optically scannable by the optical unit for position sensing. The different formation of the regions makes switching among the various measuring directions possible during position sensing, and positional signals can be generated by the optical unit relative to the relative movement of the two objects for each measuring direction.

Position-measuring device and system having such a position-measuring device

An optical position-measuring device is adapted to detect the position of an object in several spatial degrees of freedom. The object is disposed in a manner allowing it to move at least along a first direction of movement and along a second direction of movement. The position-measuring device includes at least one light source and at least one first and second measuring standard which are located on the object, extend along a first extension direction and a second extension direction and include graduation regions disposed periodically along the first and second extension directions. In addition, a scanning plate is provided, into which at least first and second retroreflector elements are integrated, the first retroreflector element extending parallel to the first extension direction and the second retroreflector element extending parallel to the second extension direction, and via which, sub-beams that fall on them from the first and second measuring standard, are reflected back in the direction of the respective measuring standard. From superposed sub-beams, a detector system is able to generate position signals at least with respect to the movement of the object along the first and second direction of movement.

In position-measuring devices and a systems having a plurality of position-measuring devices for determining the position of an object in several spatial degrees of freedom, the plurality of optical position-measuring devices scan the object from a single probing direction, and the probing direction coincides with one of the two main axes of motion.

Position-measuring device and system having a plurality of position-measuring devices

An interferometer includes a light source and a beam splitter, via which the beam of rays emitted by the light source is split into a measurement beam and a reference beam. The measurement beam propagates in a measuring arm extending in a first direction between the beam splitter and a measuring reflector. The measuring reflector brings about an offset perpendicular to the direction of incidence between the measurement beam falling on it and the measurement beam reflected back by it. In a reference arm extending in a second direction, the reference beam propagates between the beam splitter and a reference reflector. In addition, the interferometer has a detector system, to which the superposed and recombined measurement beam and reference beam are able to be supplied, and via which a distance-dependent interference signal with respect to the position of the measuring reflector is able to be generated. The measuring reflector in each case includes at least one transmission grating as well as a reflector element.

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Uebersee, Germany

Markus Meissner