WO2005071424A1

WO2005071424A1 - Detection of speed components

Info

Publication number: WO2005071424A1
Application number: PCT/EP2005/000515
Authority: WO
Inventors: Klaus Wolter
Original assignee: Klaus Wolter
Priority date: 2004-01-21
Filing date: 2005-01-20
Publication date: 2005-08-04

Abstract

The invention relates to a device for detecting a speed component, comprising a source (10), two paths (31,32) having different physical length and an evaluation device (11). The source is configured to feed coherent emission fractions into each path. Each path is configured to guide a fed emission fraction along the same route to a reflector (25, 26) closing the path and to the evaluation device after reflection by the reflector. The longer path (31) deviates from a direct connection between its beginning and the reflector (26) closing the path. The evaluation device is configured to detect any change in phase displacement between the emission fractions fed by the paths and phase displacement while the device is idle as the basis for determining a speed component. The invention also relates to a system comprising said device and a corresponding method for speed measurement.

Description

Detection of speed components

The invention relates to a device and a method for detecting a speed component. The invention also relates to a system which has at least one such device.

A wide variety of approaches can be used to measure components of the speeds of a device or system. Speed measurements are usually carried out relative to a reference system and therefore require external information. Independent speed measurements are also possible.

For the independent measurement of a speed component of a device, the device can have two paths of different physical lengths, into which wave-shaped signals are fed. Different physical lengths mean that the running time of the waves on the two paths is different when the device is idle. To determine a speed component, relative phase changes of the waves that leave the two paths, which are dependent on the speed of the device, can then be recorded and evaluated.

The relative phase changes can be recorded in particular by superimposing the signals emerging from the paths, so that the interference pattern that arises can be evaluated. To do this, the signals must be capable of interference. That means that

BESTATIGUNGSKOPIE Signals are emissions from a single source with a corresponding coherence length, or that the signals are emissions from multiple, suitably coupled sources.

The relative phase changes can result, for example, from effects according to Pizeau and Sagnac. However, relative phase changes are also caused by the second-order Doppler effect on which the present invention is based. It should be noted here that the phase shift due to the second-order Doppler effect is significantly less than the phase shift due to the Sagnac effect. The difference is on the order of v / c, where v is the speed of the device and c is the speed of light. When recording the relative phase changes, it must therefore be ensured that the Sagnac effect does not falsify the measurement result.

In the publication EP 0 220 378 AI speed measuring devices are described which are based on the second order Doppler effect.

In a basic form described, a light source emits a light beam, which is split via a beam splitter. A first partial beam strikes a first mirror and is reflected back to the beam splitter. This creates a first interferometer arm. A second partial beam hits a second mirror and is reflected back to the beam splitter. This forms a second interferometer arm. The length of the first interferometer arm is greater than the length of the second interferometer arm. The reflected

BESTATIGUNGSKOPIE Partial beams are superimposed on one another and fed to an evaluation device in which the phase difference between the two partial beams is determined. The length of the first interferometer arm in comparison to the length of the second interferometer arm determines the resolution of the measurement result. However, the length of the first interferometer arm is limited for a compact measuring device.

In a further embodiment, to extend the first interferometer arm, the first partial beam is not reflected back to the beam splitter, but is guided to a superimposition location via several mirrors. The beam splitter also feeds the second partial beam directly to this superposition location.

In the document EP 0 220 378 AI it is pointed out that during rotation a phase shift caused by the Sagnac effect additionally occurs if one or both of the interferometer arms are realized with optical fibers which enclose a closed surface. It is proposed to minimize the measurement error resulting from this by keeping the enclosed area small. However, this means that a residual error remains in any case.

As an alternative, it is proposed to measure the phase difference caused by the Sagnac effect using a suitable arrangement and to take it into account in the evaluation to determine the speed. However, this makes the setup more complex. In a further embodiment, two physically different light sources are used. In particular, a laser has two resonance spaces that are different from one another and excited via separate anodes, from each of which a laser beam is coupled out. The detection is carried out by measuring the difference between the frequencies of the outcoupled laser beams. However, the outcoupled laser beams are not coherent and therefore not capable of interference, which makes the evaluation impractical. In addition, the difference in length of the paths achieved is relatively small, which prevents high resolution.

Finally, it is stated in the document EP 0 220 378 AI that three of the measuring devices described are required for the independent measurement of a speed, with each of which a speed component is measured in different spatial directions.

The invention is based on the object of enabling an improved measurement of speed components.

The object is achieved by an apparatus for detecting a velocity component which at least a source, at least two paths of different physical length and an evaluation device ^comprises'. The at least one source is designed to feed coherent emissions into each of the at least two paths. There is therefore a fixed phase relationship between the emissions components fed in. Each is at least two paths trained to direct a fed-in emission component in the same way to a reflector closing the path, and after reflection by the reflector to the evaluation device. The longer of the at least two paths deviates from a direct connection between its beginning and the reflector closing the path. The evaluation device is also designed to detect a change in the phase shift between the emission components supplied by the paths compared to a phase shift when the device is at rest as a basis for determining a speed component.

The object is also achieved by a system for detecting a speed, which comprises one or more such devices.

Finally, the object is achieved by a method for detecting a speed component of a device. The method comprises feeding in coherent emissions in at least two paths of different physical lengths. The method further comprises forwarding a fed-in emission component on each of the at least two paths in the same way to a reflector that closes the path, and after reflection by the reflector to an evaluation device, the emission component on the longer path deviating from a direct connection between the Start of the longer path and the reflector that closes the path. Furthermore, the method comprises detecting a change in the phase shift between the emission components fed from the paths to the evaluation device compared to a phase shift when the device is at rest

BESTATIGUNGSKOPIE Basis for determining a speed component.

The invention is based on a device in which a change in the phase shift between the emission components spreading on two paths of different lengths is determined. The change in phase shift can be caused by the second-order Doppler effect as soon as the device moves. The invention is based on the consideration that the longer path to achieve a particularly long path length in a compact device can have deviations from a straight line. The invention is also based on the consideration that undesirable influences by the Sagnac effect can be prevented if there is a path to each path component in one direction of an emission component

Direction of propagation gives the same length of path in the opposite direction.

It is therefore proposed that, on the one hand, a non-rectilinear path is used, which, on the other hand, is closed off by a reflector, which ensures that an emission component that has traversed the path subsequently traverses the path in the opposite direction before it is fed to an evaluation device becomes. This avoids circular shares on the way of the emission shares.

The invention has the advantage that it enables reliable and independent speed measurement. It can be realized in the smallest space and is therefore particularly flexible and versatile. A separate compensation of the Sagnac effect in the case of a rotary movement is not necessary in order to filter out the second-order Doppler effect, since the Sagnac effect is completely compensated for by the construction of the device itself, and not only kept as low as possible as in EP 0 220 378 AI.

Advantageous embodiments of the invention result from the subclaims.

For a particularly efficient path extension, the longer path is at least twice as long as a direct connection between its starting point and the reflector closing the path due to its deviation from a straight line in one embodiment of the device according to the invention. The starting point of the longer path can be, for example, the source that provides an emission component for this path, but also, for example, the point at which an emission provided jointly for both paths is split into two emission components.

The at least one source can be designed in a wide variety of ways and provide different types of emission components. In particular, it can provide any emission components with a known wavelength. Wavelength is the universal physical wavelength that can be assigned to any object. The at least one source can comprise, for example, a light source, for example in the form of any LASER. Alternatively, the at least one source can also comprise, for example, a MASER or an electron beam source. The at least two

BESTATIGUNGSKOPIE Emission components supplied to paths can also be output simultaneously or at intervals. The only thing that matters is that the phase offset between the emission components on the two paths is known when the device is at rest. It goes without saying that a single source can generate a single emission, which is then appropriately split into the emission components. If, on the other hand, the at least one source generates several emissions, the respective emission component can also comprise a complete emission.

The paths used can also be designed in a wide variety of ways, as long as they are suitable for forwarding the emission components generated by the source. The paths can be made of the same material or different materials. A single path can also be homogeneous or inhomogeneous. It can consist of one material or consist of several parts made of different materials.

In an advantageous embodiment, at least the longer path is formed in a propagation medium by means of reflectors which repeatedly reflect an emission to lengthen the path back and forth before the emission is fed to a final reflector and which takes the same path back. Such path design can be used, for example, with a light source as the source. Compared to optical waveguides, path guidance in a propagation medium that does not limit the path via pure reflections has the advantage that entrainment effects that are present in conductors are prevented can prevent the required phase shift when the speed changes.

A change in the phase shift between the emission components spreading on the at least two paths due to a translational movement of the device can be achieved in that the emission components on the two paths take different lengths of time in the idle state of the device to traverse the path, i.e. due to different physical lengths of the paths. This can be achieved, for example, in that the geometric path length on one path is longer than on the other and / or in that the propagation speed on one path is longer than on the other, for example due to different refractive indices of different materials used. The greater the difference in transit time on the two paths, the greater the resolution of the recorded speed.

Furthermore, other influences of a rotary movement on the speed determination can be switched off in different ways.

For example, the paths can already. be designed in their geometric design in such a way that a rotational influence on the phase position of the emission components is prevented from the outset. This can be achieved in that each of the paths has essentially equally large parts of the path on opposite sides of a direct connection between its beginning and the end of the path

BESTATIGUNGSKOPIE Has reflector. The imaginary straight line usually corresponds to the measuring direction of the device.

In an advantageous embodiment of the invention, the device further comprises at least one acceleration sensor, with which a reference to the local gravitational normal can be made even without movement. This means that an acceleration sensor can be used to determine the orientation of the device in space in an initial state, from which the speed of the device is determined according to the invention.

Only a device according to the invention is required for a speed measurement in a single spatial direction. This device is then aligned in such a way that its measuring direction coincides with the desired spatial direction. In addition, the device can be rotated until a maximum change in the phase shift between the emission components is achieved. The direction of movement then corresponds to the measuring direction of the device in the position in which the maximum change is achieved.

For a simpler and faster detection of a speed in several directions, however, several of the devices according to the invention can be used in a system according to the invention, which simultaneously detect the speed in different spatial directions. Here, a single source can optionally be used simultaneously to generate emissions for several of the devices. For example, a light source can simultaneously emit a light signal in a plurality of suitably aligned paths

BESTATIGUNGSKOPIE feed. For the complete detection of translatory and rotary movements of a system, the system comprises at least six of the devices according to the invention. With a suitable arrangement of the measuring directions of the six devices, any movement can then be recorded in terms of size using mathematical calculations.

The accuracy of the measurements depends in particular on the wavelength of the emissions and on the differences in transit time on the at least two paths.

The possible repetition rate of the measurements depends in particular on the running time of the emission component on the path with the longer running time and on the time required for the evaluation.

A device according to the invention can be used to determine its own speed. In this case, the device itself can have further components and functions, in particular those for which the speed measurement is of interest. If the device is brought into a fixed relationship to another moving object, the speed of any objects can also be determined by means of a device according to the invention. The same applies to the system according to the invention.

The invention can be used in a wide variety of fields, for example for determining speed, location and position in a navigation system or for detecting the movements of a computer mouse.

BESTATIGUNGSKOPIE It goes without saying that the functions of structural features in the presented exemplary embodiments of the device according to the invention can accordingly also be used as functional features in exemplary embodiments of the method according to the invention and vice versa.

Embodiments of the invention are explained in more detail below on the basis of exemplary embodiments with reference to drawings. It shows:

Fig. 1 shows schematically an embodiment of the device according to the invention and Fig. 2 schematically shows an embodiment of the system according to the invention.

Figure 1 schematically illustrates an exemplary embodiment of the device according to the invention, which allows the detection of a speed component, i.e. the speed in a certain direction.

The device comprises a source 10 at an emission location and a phase comparator 11 with a detector (not shown separately) at a measurement location. The source 10 can be, for example, a LASER that emits a light signal.

The device further comprises a propagation medium 12 which is delimited at the top and at the bottom by smiling reflectors 21, 22. The source 10 is arranged on an imaginary, elongated straight line through the propagation medium 12 parallel and equidistant to the reflectors 21, 22.

BESTATIGUNGSKOPIE Between the source 10 and the propagation medium 12 there is a third reflector 23, which is permeable on one side, on the imaginary, extended straight line through the propagation medium 12. The phase comparator 11 is arranged below this third reflector 23.

Within the propagation medium 12, a radiation splitter 24, a fourth reflector 25 and a fifth reflector 26 are also arranged on the imaginary straight line, starting from the third reflector 23 in this order.

If the source 10 generates an emission, it first strikes the third reflector 23. The third reflector 23 allows the emission to pass, so that it enters the propagation medium 12.

On the one hand, the radiation splitter 24 in the propagation medium 12 allows a first emission component to pass without being deflected. The first emission component strikes the fourth reflector 25 perpendicularly, is reflected there and runs back to the third reflector 23. The third reflector 23 deflects the first emission component in the direction of the phase comparator 11.

On the other hand, the beam splitter 24 deflects a second portion of the emission generated by the source 10 upwards. This second emission component strikes the upper, first reflector 21, is reflected by this, strikes the lower, second reflector 22, is reflected by this, strikes the upper, first reflector 21, is reflected by the latter, etc. The deflection angle by the beam splitter 24 is so

BESTATIGUNGSKOPIE set that the second emission component is finally fed from the lower reflector 22 exactly to the fifth reflector 26. The second emission component strikes the fifth reflector 26 perpendicularly. The fifth reflector 26 consequently reflects the incoming second emission component in such a way that it takes the same path back via the second reflector 22 and the first reflector 21 to the third reflector 23. The third reflector 23 also deflects the second emission component in the direction of the phase comparator 11.

A first path 31 is thus formed between the beam splitter 24 and the fourth reflector 25 and a second path 32 is formed between the beam splitter 24 and the fifth reflector 26. The first path 31 has equal parts on opposite sides of the imaginary straight line, while the second path 32 has no parts that deviate from the imaginary straight line.

Since the paths 31, 32 are fed by the same source 10, emission components with the same phase position are fed into both paths 31, 32. Due to the different lengths of the paths 31, 32, however, the two emission components need a different time to cover the path formed by the respective path 31, 32.

At the measurement location, the emission components from the two paths 31, 32 are superimposed to form an interference signal. The phase comparator 11 evaluates the interference signal resulting from the two emission components. If the device is in an idle state, this results from the different path lengths

BESTATIGUNGSKOPIE certain phase offset between the emissions. If the device moves with a directional component that corresponds to the imaginary straight line, this phase shift changes. The phase comparator 11 determines the extent of the change and, based on this, the translatory speed of the device. The imaginary straight line also corresponds to the measuring axis of the device.

For example, a runtime of t _{x can} result on the path 31 in the idle state and a runtime of t ₂ on the path 32. The transit time t _x is greater than the transit time t ₂ , since the path 31 is longer than the path 32. As long as the device is not moving, an interference signal is thus formed at the measurement location at the times t ₀ and t ₀ + (tι -t ₂ ) generated emissions.

If the device now moves with one component in the direction of the measuring axis of the device, the propagation speed in the propagation medium 12 is reduced by v ² / c ² due to the second-order Doppler effect. Here v is the component of the speed of the device in the direction of the measuring axis and c is the speed of propagation in the propagation medium 12 when the device is stationary. A runtime of t _x -Δtι then results on path 31 and a runtime of t ₂ -Δt ₂ on path 32. Due to the different path lengths, Δti is greater than Δt ₂ , the extent of the difference depending on the speed of the device in the direction of the measuring axis. The phase shift between the two emission components at the measurement location also changes depending on the

BESTATIGUNGSKOPIE Speed of the device in the direction of the measuring axis.

The change in the phase shift between the emission components on the two paths 31, 32 results in a periodic interference signal consisting of emission components generated at times t ₀ and t ₀ + ((tι-Δt _x ) - (t ₂ -Δt ₂ )).

The phase comparator 11 determines the extent of the phase change on the basis of the interference signal and the translational speed v of the device in the direction of the measurement axis on the basis of this.

The general combination of source 10, paths 31, 32 and phase comparator 11 corresponds to the Kennedy-Thorndike interferometer.

The determined speed can then be used in any way, for example for an immediate display of the speed on a display unit or for calculations in a navigation system. The components required for the further processing of the determined speed can be integrated in the device 1 or connected externally to it, for example as part of another device.

A separate compensation of the Sagnac effect in the case of rotary movements is not necessary, since such effects are compensated for by the construction of the device itself. Figure 2 shows schematically an embodiment of the system according to the invention, which allows a measurement of any translational and rotational speeds.

The system is in the form of a cube. Each of the six sides of the cube comprises one of the devices according to FIG. 1. The measuring axis 50, 51, 52 of the respective device is indicated on the three visible sides of the cube 40, 41, 42. The three hidden sides of the cube each comprise a device with a measuring axis in opposite orientation compared to the measuring axis 50, 51, 52 of the device on the opposite side of the cube 40, 41, 42. A processing unit (not shown) evaluates the one recorded for the six directions Speed of the system and determines the total speed of the system, including translational and rotary

Speed components, and the direction or directions of movement.

A method or an apparatus which has already been proposed is described below. This method and / or this device for measuring speed vectors is based on the effects according to Fizeau, Sagnac and Doppier and is characterized in that there is at least one (and or more) emission location at least one (and / or more) source, the Emission itself on at least two paths, each with a known speed and a known wavelength (here the universal physical wavelength is meant that each object assignable) and spreads evaluable interferences in particular, but not necessarily only for the time of the respectively necessary measurement duration at one or more measurement locations, as well as at least one of the paths from the emission location (s) of this type to the location (s) Measuring location (s) in such a way that the phase position given on this path is shifted against that of another path by a translational event. The paths ^" are shown in such a way that a rotational event, a thermal or other non-translational influence does not result in a shift in the phase position between these paths, or these superposing events and influences are corrected by (= external) devices lying outside the paths The shift of the phase positions (= measurement signal) which the interference signal of these paths gives is then a measure of the speed. The direction results as ^' the spatial direction for which the measurement signal becomes maximum for the given paths (= path greatest difference). In particular, so, if a defined speed vector is specified, determine the measuring axis inherent in the device.

The paths described above do not necessarily have to be homogeneous, which means that they can also be composed of several different sections in each case.

The named effects and thus the measurement signal occur when the emission can spread unhindered on the planned propagation paths; in other words: the emission has the necessary degrees of freedom for its propagation and thus the necessary degrees of freedom for the

BESTATIGUNGSKOPIE Occurrence of the effects. Illustrated and thus put simply: Is z. B. a photon in an optical waveguide exists only in the longitudinal mode, there is only one degree of freedom in this mode and only in this degree of freedom there will be detectable effects. The selection of a preferred measuring direction can and is predetermined by the construction and physical properties of the sensor, that is to say by determining the degrees of freedom of the propagation.

In other words, the previously proposed method and / or the previously proposed device is characterized in that a source of whatever type is shown with emission locations for radiation that have a known phase relationship between the emission locations of the measurement process - these emission locations can have spatial and / or or have a time interval - and for each of which the paths (= paths) have a (as large as possible) shift in the phase positions with respect to a translatory movement.

The wavelength of the emission and the difference in transit time along the paths are decisive for the possible resolution of the previously proposed method and / or the previously proposed device. The capabilities of the phase comparator as well as the static and systematic errors are subordinate.

There are now a variety of preferred embodiments for the implementation, from which only a few are emphasized here, however, since these

BESTATIGUNGSKOPIE within the manifold represent special cases of the principle and other embodiments are modifications of this.

In one embodiment, the source is a light source. Generally a laser of any type (linear ring laser (this can of course still be used for angle measurements) solid-state, gas, and liquid lasers, just to present the generic terms. Techniques such as exotic physical effects such as quantum well and superfluorescence or similar must be probably not be listed individually). And so the known speed is the speed of light.

In a further embodiment, the source is any kind of burl.

In further embodiments, in particular, variations with materials in which the propagation speeds are different can be specified as solutions for the paths, as well as variations in path lengths as well as the combination of both approaches.

There are again several options for compensating for rotational phase shifts. One is the geometric design of the paths - the parts of a path outside the connecting line between the beginning and end must behave in such a way that each part on one side has an equally large part on the opposite side - another is the computational compensation by determine the rotation by means of z. B. laser gyroscope and a subsequent subtraction.

In all embodiments, the emission is divided between the paths and brought together again for interferometric evaluation.

The lock-in effect has an effect on the design of some embodiments (to put it simply: the fixation of a vibration node to an interfering part). In these cases, the lock-in effect is necessary for at least two of the three room dimensions. If it is not available for one spatial direction (e.g. laser gyroscope), the path of greatest difference must have a vector component orthogonal to this spatial direction in order to obtain a usable measurement signal. The reason for this is that in this case the Sagnac effect does not play a role in the movement in this lock - in free space dimension, but rather the shift of the phase due to the shift in the emission location due to the speed in interaction with the different transit times to the individual paths comes about. However, this result cannot be clearly assigned to this lock - in free direction of space, since a phase shift in this arrangement is also caused by a speed component in the direction of the path of greatest difference due to the Sagnac effect (see below) the speed in this area spanned by the path and the lock - in effect. A speed component normal to this area gives no signal. If this vectorial speed measure is linearly independent of this and with the measures of analogously determined vectorial speed measures

BESTATIGUNGSKOPIE combined at the same time linearly independently of other surfaces, the result for simple velocity calculation is the measure of the speed in space. On the other hand, in the case of a lock-in effect that is present for all spatial directions, there is no restriction and the Sagnac effect provides the shift.

In the event that the lock-in effect in these embodiments is present in all spatial directions, the two paths (path 1 have a signal propagation time of ti and path 2 have one of t ₂ and let t _x > t _2. Eg ti = a * t ₂ ) a signal with identical phase position is fed in at time t ₀ . If the device does not move, there is an interference signal at the measuring location formed from the signals emitted at times t ₀ and -t ₀ + (tχ-t2). Now the device with a

Velocity v = Δl / Δt moves, so the displacement due to this movement and the respective path add to both paths, i.e. the respective transit time becomes longer (Sagnac effect), namely for path 2 by Δt and for path 1 by a * At. This means that at the end of path 1 there is a phase that corresponds to the phase position of a path with the transit time ti + a * Δt and that there is a phase at the end of path 2, since the original phase was carried away by the lock-in effect, the the

Phase position of t ₂ + Δt corresponds. And this change in the difference in the phase positions as a function of the speed v by (a-1) * Δt results in a periodic interference signal.

BESTATIGUNGSKOPIE In the event that the lock-in effect does not exist for a spatial direction in these embodiments, the path greatest difference must have a vector component orthogonal to this spatial direction, as already described. For this vector component, there is a change in the phase difference by (a-1) * Δt in a manner similar to the one above.

The previously proposed method and / or the previously proposed device for measuring speed vectors captures all speeds / speed vectors in sum in the case of a three-dimensional measurement, e.g. starting from the speed of the Milky Way in the universe known to us, to the movement of the solar system with respect to of the galactic center, about the movement of the earth in the solar system, about the movement of the earth itself, as well as the movement of the earth's crust up to the self-movement of the object to be measured, such as the self-speed of the device itself. To determine the correspondingly considered vector component, the others must therefore be subtracted.

Another embodiment uses, for example, in particular a laser, a laser diode (consequently a linear gas, liquid or solid-state laser, as well as a ring laser of whatever type) as the source. From the light emission location of this laser, for example, a light waveguide (= fiber optic) split after a short distance now leads, one branch (= path) after the split is longer (in the sense of the one previously written) than the other and is brought together again for the purpose of interference formation. At the end there is an interference evaluation device (Phase comparator) attached, for example, with a photodiode as a sensor. There the phase position of the previously emitted (stored) light is then compared with that of the later emitted light. The optical fiber is now laid according to the requirement (see above) for selecting a spatial direction. Or a physically analog structure with reflectors and beam splitters is used. In particular, the light of the laser used here can be used at the same time for all of the further split optical waveguides for measuring further spatial directions.

Another preferred embodiment uses the structure of well-known fiber gyros in principle. The main difference here lies in the design of the sensor head (= paths). This does not consist of a wound fiber optic fiber, but of paths constructed according to the above regulations. In particular, the light of the laser used here can be used at the same time for all further appropriately arranged optical fibers for measuring further spatial directions. Instead of extending one part of the path by folding, the change in the speed of propagation in the medium can also be used to "lengthen" the path by using a material with a different refractive index. This of course also through and in combination of both forms. The following applies: the greater the difference, the greater the resolution, the more sensitive the execution.

In order to get an idea of the size of the measurement effect, the resulting shift is based on a

BESTATIGUNGSKOPIE typical walking speed of 3.6 km / h. clarified (3.6 km / h = 1 nm / nsec) with an assumed distance of the light emission locations of one light nanosecond (approx. 30 cm) and a wavelength of light of 400 nm, this results in a well controllable measurement variable.

The potentially possible repetition rate for measurements is essentially given by the duration of the emission on the longer path and the subsequent processing of the signal and is in the upper megahertz range.

Since the previously proposed method and / or the previously proposed device represents an inertial working system, a reference to another moving object is e.g. B. represents by a simple contact to this. Otherwise, the device shows the airspeed vector of itself.

In a further preferred embodiment, a path is used at least twice by the emission radiating through it in both (opposite) directions. The advantage of this is the saving of a path for one measuring direction in order to minimize the components and the reduction of thermal and other path conditions.

In a further preferred embodiment, this one path is replaced by two separate paths.

In a further preferred embodiment, for complete detection of a movement - translation and rotation - at least six of the devices represented by the above method are now distributed in space such that the

BESTATIGUNGSKOPIE Measuring signals of the measuring axes given by the method and / or the device can be unambiguously separated by a suitably chosen mathematical calculation rule into the space vectors characterizing a movement - translatory and rotational speed. The resolution of the rotational speed is improved by increasing the distances between the devices and thus the measuring axes. An example of the arrangement is the placement of six devices on the six faces of a cube.

In a further preferred embodiment, in which complete detection of a movement is not desired and / or required, measurement axes that are not required are omitted and / or replaced by other methods and or devices.

In a further preferred embodiment, the method and / or the device is supplemented by one or more acceleration sensors, so that a reference to the local gravitational normal can be established without any movement.

In a further preferred embodiment, the method and / or the device is replaced by one or more spirit levels or the like. added so that a reference to the local gravitational normal can be made without any movement.

The device according to the invention or the system according to the invention can be varied in many ways, including according to a method described below and a device described below.

BESTATIGUNGSKOPIE The method and / or the device according to the invention for detecting the degrees of freedom of movement in space differs from the embodiments and claims of the previously proposed method and / or the previously proposed device for measuring speed vectors only in that another, but by the factor v / c (v = own speed of motion; c = speed of light) smaller effect is used for the measurement of the speed vector components. This effect is the so-called second-order Doppler effect. This is filtered out of the signal range if the portion of the Sagnac effect is eliminated by appropriate feedback with the same path length. In 1986 Manfred Böhm made suggestions for interpretation and execution with sustainable errors in his essay “Inertial Navigation Without Accelerome ers * (M. Böhm, SEL - Standard Elektrik Lorenz AG, Lorenzstraße 10, D-7000 Stuttgart 40). The basic physical principles are also described there. As an essential prerequisite for the functionality, the necessity of the interference capability of the emissions used should be pointed out here again, which means that the emission comes from a source with a corresponding coherence length or, in the case of multiple sources, is coupled in such a way that this is guaranteed (e.g. by a Coupling the emission from one source to the other, as well as vice versa and corresponding coordination of the geometry and the excitation, to name just a few parameters).

To avoid these errors, the method and / or the device for detecting the

BESTATIGUNGSKOPIE Straight line of freedom of a movement in space presented. First of all, only the basic part of the method and / or the device, the signal transmitter, the measuring head in which the signal, ie the measure for the speed, is generated before the whole is shown in further preferred embodiments.

One of the essential errors, the indistinguishable superimposition of the desired translatory signal with a rotary component, can be seen directly from Figures 9.1a and 9.1b in Chapter 9 of the article by M. Böhm cited. Paths are constructed there which in both cases have circular parts or complete circles which produce a signal caused by the much stronger Sagnac effect in the event of rotation. Although the note in Figure 9.1b refers to the Sagnac effect, the drawings show that this only means the compensation of the Sagnac part of the translation, but not the Sagnac effect caused by the winding for the rotation has been. This is particularly evident from the fact that Böhm makes this equally wrong in both Figures 9.1a and 9.1b. This makes these devices unusable. Chapter 6 of his essay shows that Böhm is aware of the Sagnac effect of rotation, which also shows that he does not mean the Sagnac effect of rotation here. The version from Figure 9.2 of this article avoids circular parts or circles, however, has other shortcomings, one of which contains the paths described there for the small difference in length and another is described below. The order of magnitude for the meaning of the dimension factor is illustrated using an example (see

BESTATIGUNGSKOPIE Chapter 8, and especially the formula in Figure 8.1). It is a good assumption to set the geometry factor K to 1 (chap. 5), the length difference I01-I02 is preferably one meter, the wavelength λ is 500 nm, the speed v is 300m / s (speed of sound) and the speed of light c for the sake of simplicity, assume 3 ^* 10 ⁸ m / s. Then ΔΦ is very small at 0.2 10 ^"5 and becomes almost no longer measurable in an application that is interesting for universal handling. The laser would have at least the same extent at Δl of one meter in this representation as in 9.2. The measured variable would be ΔΦ at a speed v of 3 m / s by a factor of 10 ⁴ less, i.e. at 0.2 ^* 10 ^"9 .

By using a path now designed according to the older proposals, e.g. In the wound eight or the like, which do not allow any rotating components, the Doppler effect filtered out in this way becomes measurable (9.1 a / b) or only comes into a usable order, but still too small by v / c by extending one of the paths in Figure 9.2. The version from Figure 9.2 also differs fundamentally from those from 9.1 a / b, through the use of two physically different light sources, which leads to a lack of coherence and thus makes the structure impractical (see also the author's own argument in 9.1 b) , The solution to control coherence through appropriate measures, as suggested above, is no longer available at Böhm.

All of these now proposed for the method according to the invention and / or the device according to the invention for detecting the degrees of freedom of a movement in space

BESTATIGUNGSKOPIE Hiding the Sagnac effect is common to embodiments of the paths. This is achieved in that for each path component in one direction there is a path length in the opposite direction that is always of the same length with respect to the propagation duration, so that the Sagnac. - Effect is compensated. As already mentioned, in a preferred embodiment this is an optical waveguide which is wound in the form of an eight and which then has a mirror at one end in order to mask out the Sagnac effect for translation.

So-called paths are then brought together in further preferred embodiments in the manner of the Kennedy-Thorndike interferometer (Figure 8.1 of the cited article) using a suitable source (see above) and the necessary phase detector (Fig. 1).

All preferred embodiments that are suitable for detecting the degrees of freedom of a movement in space have already been described in the older versions and are adopted from there.

Areas of application are location and location determination of various objects and subjects or parts thereof, of which only a few are listed as examples:

Writing instruments such as Pen, ballpoint pen, computer, computer mouse, bicycle, motorcycle, automobile, special vehicles such as cranes, mobile bridges, construction and cargo vehicles, railways, transrapid, helicopters, guided missiles, aircraft, spacecraft, ships, submarines, military vehicles of all kinds, bullets , Grenade, rocket, household appliances such as Vacuum cleaners, lawn mowers, robots for household and industry, industrial devices such as rollers,

BESTATIGUNGSKOPIE Cranes, forklift trucks, transport pallets, mining and tunneling machines, such as drills, milling cutters, offshore applications such as platform stabilization, deep drilling rigs, toys such as dolls, animals, automobiles and sub-components thereof, as well as any object whose degrees of freedom of movement are to be determined and / or regulated.

Human, as well as parts of human, such as. B. fingers, hands, arms, legs, feet, head and trunk. Even internal parts such as the organs or their parts.

Animal, as well as parts of it (see man)

The described embodiments represent only selected from a large number of different possible embodiments of the method and the device according to the invention.

BESTATIGUNGSKOPIE

Claims

3E

P A T E N T A N S P R Ü C H E

Device for detecting a

Speed component, comprising at least one source (10), at least two paths (31, 32) of different physical lengths and an evaluation device (11), the at least one source (10) being designed, coherent emission components in each of the at least two paths (31, 32), wherein each of the at least two paths (31, 32) is designed, an input emission component in the same way to a reflector (26, 25) closing the path, and after reflection by the reflector (26, 25) to the To guide evaluation device (11), wherein the longer of the at least two paths (31) deviates from a direct connection between its beginning and the reflector (26) closing the path, and wherein the evaluation device (11) is designed to detect a change in the phase shift between the emission components supplied by the paths (31, 32) compared to a phase shift with the device at rest as the basis for the determinations tion of a speed component.

The apparatus of claim 1, wherein the longer path (32) through a plurality of reflectors (21, 22)

BESTATIGUNGSKOPIE and wherein the reflectors (21, 22) are arranged to transmit a first emission component provided by the source (10) by reflections on the longer path (32) before the first emission component from the reflector closing the longer path (32) (26) by reflection in the opposite direction is led back to the longer path (32).

3. The device according to claim 2, wherein the longer path (32) between the reflectors (21, 22) is formed in a propagation medium which does not delimit the path (32).

4. The device according to claim 1, wherein each of the at least two paths (31, 32) has substantially equal path components on opposite sides of a direct connection between its beginning and the reflector (26, 25) closing the path.

5. A system for detecting a speed, comprising at least one device according to one of the preceding claims, wherein the at least one device for measuring at least one speed component of the system is arranged.

6. System according to claim 5, comprising at least six devices according to one of claims 1 to 3, which are arranged in the system for measuring speed components of the system in six different spatial directions (70,71,72).

BESTATIGUNGSKOPIE A method for detecting a speed component of a device, comprising: feeding in coherent emission components in at least two paths (31, 32) of different physical lengths, forwarding a supplied emission component on each of the at least two paths (31, 32) in the same way to a reflector closing the path (26, 25), and after reflection by the reflector (26, 25) to an evaluation device (11), the emission component on the longer path (32) deviating from a direct connection between the beginning of the longer path (32) and is guided to the reflector (26) closing the path, and detecting a change in the phase shift between the emission components fed to the evaluation device (11) from the paths (31, 32) compared to a phase shift when the device is at rest as a basis for determining a speed component.

The method of claim 7, comprising determining a speed component in six different spatial directions (70, 71, 72) by at least six devices, and determining the translational and rotational speed of a system comprising the at least six devices from the speed components recorded for the respective device.

BESTATIGUNGSKOPIE