DE102013104009A1 - Carrier structure i.e. joint, for measurement of two-dimensional bend in e.g. daisy-chain-circuitry in conductor film, has recess with axial spacing and/or orthogonal spacing bridged by sensor in measurement-technical manner - Google Patents

Abstract

The structure has a recess with an axial spacing to the structure so that alteration of the axial spacing and/or orthogonal spacing is carried out during bending of the structure. The axial spacing and/or the orthogonal spacing are bridged by a sensor e.g. path sensor and pressure sensor (8), in a measurement-technical manner. The sensors are connected with each other by a bus system in supply-technical, measurement technical, control-technical and/or information-technical manner. The sensors are connected in a helical or meander-shape. Independent claims are also included for the following: (1) a device comprising a carrier structure (2) a daisy-chain-circuitry.

Description

The invention relates to a support structure for measuring a bending, wherein the support structure has a first recess with an axial spacing and / or a second recess with an orthogonal spacing, so that upon bending of the support structure substantially a change of the axial spacing and / or the orthogonal spacing takes place, and a device having the support structure.

It is difficult to measure bending of a cable centerline or the midplane of a flat elastic body. Although film-laminated bending sensors are available. However, these measure deflections only in one dimension and are rigid in the remaining dimensions. So they can not be used for a two-dimensional bending measurement in the cable cross-section.

If no bending sensors can be accommodated directly in the cable core, sensors must be accommodated in an outer measuring layer. These then measure a compression or expansion of the outer layer relative to the center line. All sensor systems that measure a distance for this have the problem that they must be fixed in the measuring layer at two axially offset points. In order to allow bending of the cable, the measuring layer of the cable must also be flexible (elastic or plastic). It then becomes difficult to determine if the sensing path of the sensor is moving or the flexible regions around the sensor mounting.

The object of the invention is to improve the prior art.

The object is achieved by a support structure for measuring bending, wherein the support structure has a first recess with an axial spacing and / or a second recess with an orthogonal spacing so that upon bending of the support structure there is substantially a change of the axial spacing and / or the orthogonal spacing , wherein the axial spacing and / or the orthogonal spacing is metrologically bridged by a sensor, in particular a displacement sensor or a pressure sensor.

Thus, a support structure can be provided, the location / expression in the room is directly detectable. In particular, this can be implemented by incorporating the support structure into a flexible spatial structure or enclosing / enveloping the spatial structure with the support structure.

In particular, the spatial structures may be lines, cables, hoses, cables or flat elastic bodies, such as foam mats or textiles.

In addition, the location - determining the spatial position - of components is feasible. Implementations are, for example, machine parts that are not connected to other links via simple mechanical connections (bearings, joints, linear guides) (for example, multi-link or sliding guides with complex gangway paths) and whose position can not be detected with simple sensors (rotary encoder, linear sensor).

Parts of handling equipment can also be monitored. For example, e.g. extra personnel are required to operate the delivery crane for operating concrete pumps. It would be simpler if the worker on the concrete outlet hose could control the crane directly by specifying the hose position.

Also vehicle connections can be located, e.g. between motor vehicle and trailer. Thus, various questions can be answered: Is the trailer in a critical situation? Is there a risk of dizziness? Should the vehicle stop? Should the speed be reduced? Should the connection be broken? Should the trailer brake automatically?

Furthermore, hoses can be located by fuel dispensers. It can be determined if the fuel nozzle is on the ground or if the hose is stretched too much, e.g. if it was forgotten to take it off. In both cases, the delivery pump of the pump can switch off immediately.

Other feasible scenarios include cameras in TV studios. With the implementation, a model of the distribution of the cameras is available at any time. In the direction could be displayed on an overview map, which cameras where can be selected and which images they deliver. Likewise, headlights can be located.

Especially interesting is the location of the structures in rescue or disaster scenarios, as, for example, fire hoses and the operating forces are locatable - even if poor visibility conditions are given and in buildings no exact position determination by radio is possible. Also, robots can be located in disaster scenarios - even if poor visibility conditions are given and in rubble no exact position determination by radio is possible.

A localization can also be made for documentation purposes. For example, photos with a local spatial reference could be created if the receiving camera is connected to a location sensor and the scene objects. This can be useful, for example, when documenting complex machines. Likewise, complex piping can be documented from the inside.

Also, a cable end or a part of the support structure can be used as an input device for machine control. Classically, machines are controlled manually via so-called joysticks. Movement directions for machine parts, e.g. Set robotic or excavator arms and then integrated by the movements over time to positions. With a cable that is held in the hand with one end and that constantly provides three position coordinates and three angles of inclination across the cable end, end positions of such machines can be specified directly. The machine control can then itself determine an optimal sequence of movements of the machine parts, which in total can achieve the desired end position.

Likewise, a cable end or a part of the support structure can be used as an input device for computers. For example, for navigation in virtual worlds, for interaction in game scenarios or for designing graphical models.

For use as an input device, buttons can be integrated into the hand-held end, allowing further interactions. In particular, a key can be used to connect and disconnect the coupling of the coordinate system of the input device with the coordinate system to be controlled. Thus, the interaction area can be expanded intuitively, as it is e.g. is also realized when implementing a computer mouse.

The cable end can also be used like a virtual modeling tool. You could do it e.g. like holding a carving knife in hand to remove parts from virtual models. In the other hand, you could hold the end of another cable sensor. This can represent the virtual model. Three complex positioning tasks are now completely intuitive: first, the orientation of the workpiece (the virtual model), second, the position of the (virtual) tool relative to the workpiece, and third, the effective direction of the tool relative to the workpiece.

In addition to the pre-location of the end position with three position coordinates and three angles of inclination, with the cable sensor these coordinates and angles can also be determined for each cable section. Thus, a continuous shape determination is possible. On this data further evaluations can be made. In particular, whether a critical shape is given, cable parts reach critical positions or critical speeds are given.

This can be used in particular to monitor machines carrying cable tows. This can e.g. Welding, painting or washing robots but also cranes and trolleys. Again and again these machines have the problem that their cable tows entangle / knot or catch other objects in it. By monitoring the cables and stopping the machines before they break your connections, expensive downtime can be avoided.

In the same way it is possible to monitor whether electric bones risk destroying their own cables. In particular, e.g. Electric chain saws, hedge trimmers, grass trimmers or lawn mowers are stopped before they cause damage.

In principle, with the invention, shape determination of cable-like objects can be realized. These include the current position of endoscopes or pipe robots. For example, the following questions can be clarified:
Which way did the cable-like connection take? What is the spatial shape of the tube or the intestine, for example? How is that located, what is being considered? For example, where is a defective part that has been identified via an industrial endoscope in an aircraft engine? How should tools be positioned to intervene?

A flexible conduit may be flowed through by e.g. Solid particles, a viscous fluid, light or sound waves. Depending on the bends of the line this current varies. When a shape sensor is attached to or around this lead, the impairment of the current can be modeled. It can then be made monitoring and compensation measures. In particular, for a laser welding system, which transmits the laser light through a light guide, which is guided by a mehrgliedigen robot arm, the intensity can be readjusted. It can also be monitored how often bends have been made in which areas of the pipe. Thus, it can be predicted precisely when and at which points the line will exhibit material fatigue phenomena. It is then no longer necessary to exchange the line at regular intervals. For safety reasons, these intervals are often much shorter than the actual achievable lifetime

For creating virtual wiring and piping, the sensor can be used as an input device. In particular, such sensor cables can be fed into machines or bodyshells of, for example, cars or aircraft. Thus, the virtual model of the device can be expanded with virtual cables and tubes. Thus, problems can be identified and avoided at an early stage of development.

The shape recognition can be used for optimization of transmitting and receiving devices with flexible antenna systems. This is particularly interesting if the transmission and reception characteristics are also utilized for a localization measurement. In particular, towed antennas of watercraft change their shape as a result of the course and the flow. If the shape of the towed antenna is known, the transmission channels can be modeled more precisely.

Shape detection using a sensor cable can be used to measure flexible objects. In particular, bearing characteristics of skeletons can be measured. This can e.g. provide physiotherapy with valuable information about the extent to which individual limbs are movable in relation to others. Legs, arms, fingers and in particular the spine can be measured so precisely.

In addition to the cable-like structures and surface shape sensors can be realized. For this purpose, the cable-like structures can be arranged in parallel or support structures and measuring sections can also be realized in a two-dimensional arrangement. In general, machines that use flexible flat parts can be monitored. In particular, such shape detection can be used if other shape detection methods (e.g., optical) are poorly possible, technically too expensive, or too expensive.

With surface shape sensors, a shape detection of seats, upholstery and beds can be done. Seat and couch profiles can be accommodated and furniture made for special users. Adaptive furniture and especially travel seats in cars, trains and airplanes can automatically adjust to the user.

Also, capturing profiles for ergonomics improvement and monitoring is feasible, e.g. Paralyzed or demented patients can be monitored who can no longer rotate themselves in bed regularly. In particular, decubitus prophylaxis for sitting and lying equipment can be realized.

For equitation, a flat back measurement of a horse can be done. Based on this data, an optimized saddle can then be manufactured. Since the sensor also provides information about the back and saddle shape during riding, a finished saddle can be further optimized and configured.

Furthermore, a planar shape sensor can be used as an input device for computers, e.g. in game scenarios or to design graphical models. In particular, directly three-dimensional shapes can be specified in order to use them in a CAD development can. So one could e.g. directly specify the shape of a fender. The three-dimensional models can run simultaneously in a flow simulation. This results in an intuitive access to functional properties of the modeling. In the example of the fender, it would be possible to see how the flow situation around the entire vehicle changes if one makes (manually) local changes to the fender. With interactions via a computer mouse, which can only change sequential local geometry points, this would be much more involved and not so intuitive.

The planar shape sensor can also be used to detect deformations. In particular, when used in crash test scenarios can be tracked, which parts have deformed in which sequence as. This also applies to areas that can not be meaningfully detected by a camera, e.g. in Holmen or generally between closely installed parts.

In principle, furthermore, an arrangement of shape sensors along sub-objects can be realized with the invention. Thus, monitoring of inflatable objects and machines using inflatable bodies can be monitored. As an example, here are emergency slides for aircraft or liferafts of ships, where each can be determined whether they have unfolded properly or may need to be countered in heavy weather. In general, besides the shape, it is also possible to determine force distributions in elastic surfaces.

For sails or paragliders, the shape can be determined at different flow conditions. This information can be used to further optimize their shapes during manufacture and also to adjust the guiding parameters during use in such a way that optimal conditions result.

In addition, a monitoring of clothing can be done. The realizable applications include, in particular, the so-called motion capturing, which is more precise than the classical one Point-based motion capture, as it can be realized, for example, for curved back sections. In addition, there would be no problems with occlusion (as with optical sensors), disturbance of the magnetic field geometry (as with flock of birds techniques) and no problems with drift (as with inertial sensors). It is particularly advantageous that monitoring of work suits (diving suits, safety suits, Waldarbeiterkombis) can be realized. So-called tracking and monitoring of body parts is possible (is the worker still moving?). When using related Waldarbeiterkombis can be determined, for example, where a saw is relative to the body and, if necessary, the saw can be stopped.

The following concept is explained:
A "support structure" is constructed such that upon bending, the material forming the support structure remains substantially unaffected. During bending, the support structure follows bending, with bending in particular affecting the "recesses". In simple terms, bending affects the recesses, but not the material forming the structure of the support structure. It should be noted that, of course, the material of the support structure or the support structure itself can also be changed by bending, but this is negligible compared to the effects on the recesses, since these effects on the recesses are at least five times, more preferably ten times greater than on the material of the support structure or the support structure - for example, by radial torsion - itself.

The support structure behaves rigid with respect to compression and expansion in the axial direction. These changes are only made by the surrounding material. Therefore, the support structure can also be guided relative thereto and in particular also be formed by a Bowden cable. The support structure corresponds to u.a. the inner of the Bowden cable. The surrounding material corresponds to the outer part of the Bowden cable.

A simple form implementation of the support structure is a coil spring. The helical shape is made by a bent steel wire. Between individual helical arches are the recesses. Opposite Helikalbögen form in particular a "Axialbeabstandung" from. If the helical spring is bent about a central axis, the steel remains substantially unaffected and the bending substantially affects the distances of the opposing helical arches (axial spacing), whereby the radial torsion of the helical spring profile is negligible. So some helical arches move closer together - there is a compression - and 180 ° offset helical arches further apart, so that an expansion takes place. Instead of the steel wire, a wound film can form the helical shape.

The support structure may in particular follow a two-dimensional bend. In particular, both dimensions are formed by two linearly independent axes oriented orthogonal to the central axis.

Through the location (on the central axis) and thus a linear axis and the two linearly independent axes, a point in space can be uniquely determined by means of a Cartesian coordinate system.

The "orthogonal spacing" is in particular a (partial) distance of a component of the support structure in the direction of the central axis or opposite to this direction. Using the example of a helical support structure, the orthogonal spacing is, in particular, the shortest distance of a helical arc from the center line, and thus the orthogonal spacing corresponds in particular to a radial spacing. Also fractions of this shortest distance are included. In addition, the orthogonal spacing may describe a distance having an angle to the axial direction.

By the term "Axialbeabstandung" also fractions, but also larger distances are included.

In "metrological bridging", the axial spacing and / or the orthogonal spacing are determined. The distances can be determined directly - by means of displacement sensors - or indirectly - by means of pressure sensors. Displacement sensors are preferably used to determine the axial spacing, pressure sensors preferably being used to determine the orthogonal spacing. Pressure sensors may also be used for determining the axial spacing and displacement sensors for determining the orthogonal spacing.

In order to determine a spatial course, the support structure may have two, three, four or more sensors. In addition, by the multiple attachment of sensors, the two-dimensional extent can be determined. Thus, two sensors can be mounted offset 90 ° to each other to allow this determination in principle.

In order to determine both the strains and compressions and to correct measurement errors, four sensors can be arranged offset by 90 ° to each other.

In order to enable a spatial resolution of the bend, a corresponding number of sensors can be arranged along the central axis.

In particular, the support structure can be arranged around a polygonal "soul" so that, for example, cables with a circular or oval cross-sectional area can be formed. Polygonic souls include triangular, quadrangular, or polygonal cross-sectional faces. In this case, for example, the soul can be made hollow.

In one embodiment, the two, three, four or more sensors, supply technology, metrology, control technology, control technology and / or information technology, in particular by means of a bus system, connected to each other. As a result, an optimized evaluation and supply of the individual sensors can be ensured. In addition, a space-saving energy supply and information evaluation can thus be realized.

In the "bus system" in particular serial bus systems are preferred. For example, an RS-232, RS-485, SPI, I ² C or CAN bus can be used to transmit and evaluate information (data and / or signals).

In order to ensure a supply of the sensors despite the bending, the connection between two or more sensors can be configured helically or meandering. In both cases, the loops given by the helical or meandering form, despite stretching, allow for a supply of energy or the transfer of data. In addition, the support structure itself may have helical or meandering components.

In another embodiment, one of the sensors is a resistive, capacitive, inductive, optical and / or pressure-sensitive sensor. As a result, different sensor types can be used. In addition, according to the measurement requirements, certain sensors can be selected according to accuracy or cost.

• – Resistiv: Zwischen zwei Elektroden kann ein Material eingefügt werden, welches bei einer Längenänderung eine Widerstandsänderung zeigt. Sollen Messungen im Millimeter- bis einige Zentimeterbereich erfolgen, kann man zum Beispiel mit Metallpulver, Metallfäden oder Graphit versetzte Elastomere oder Schäume einsetzen. Gegenüber den klassischerweise zur Bestimmung von Längenänderungen eingesetzten Dehnungsmessstreifen hat das den Vorteil, dass nicht nur Längenänderungen im Mikrometerbereich gemessen werden können.
• – Kapazitiv: Wenn der Abstand zwischen zwei gegenüberliegenden Elektroden oder die Dichte des dazwischen liegenden Dielektrikums verändert wird, ändert sich die Kapazität dieses Aufbaus. Die Auswertung kann über klassische Brückenschaltungen erfolgen.
• – Induktiv: Dabei werden magnetische Felder ausgewertet, welche von einem Sender (z.B. Elektromagnet) ausgesandt werden. Die Intensität der empfangenen Signale hängt vom Abstand ab. Bei dieser Art der Messung können die Kabel abgeschirmt werden, damit externe Magnetfelder das Messsignal nicht verfälschen.
• – Optisch: Die zu messenden Abstände liegen im Millimeter- bis einige Zentimeterbereich. In diesem Bereich kann ausgenutzt werden, dass typische Sendedioden (z.B. IR oder UV) oder LASER eine weitwinkelige Strahl-Charakteristik besitzen, die einen starken Gradienten der Intensität in der Ausbreitungsrichtung zeigen. Dies kann im Nahbereich ausgenutzt werden, um mit Photodioden oder -transistoren die von der Weglänge abhängige Intensität zu empfangen und auszuwerten. Über Serienwiderstände kann eine Spannung abgeleitet werden, die direkt einer Analog/Digital-Wandlerstufe zugefügt werden kann. Die Abhängigkeit dieser Spannung von der Abstandsveränderung kann in engen Bereichen als proportional genähert werden. Wird eine größere Genauigkeit gewünscht, können die Werte mit Funktionen korrigiert werden, deren Parameter sich aus dem Kalibriervorgang ergeben. Der Intensitätsgradient in Ausbreitungsrichtung wird noch vergrößert, wenn die Messschicht komplett mit einem flexiblen Material gefüllt wird, dass optisch diffundierend wirkt, wie z.B. Polyurethan oder Silikon mit z.B. Titanoxid versetzt. Durch die homogene Füllung wird insbesondere die Herstellung eines Sensorkabels vereinfacht und es ergeben sich von außen betrachtet relativ homogene Kabeleigenschaften. Durch ein Verwenden eines opaken Mantels, ist die optische Übertragung sehr robust gegenüber äußeren Störeinflüssen und Bauteile sowie Aufbau ermöglichen eine hohe Langzeitstabilität der Sensoreigenschaften.

The following conceptual is explained:

• - Resistive: A material can be inserted between two electrodes, which shows a resistance change when changing the length. If measurements are to be made in the millimeter to a few centimeters range, it is possible to use, for example, elastomers or foams mixed with metal powder, metal threads or graphite. Compared to the strain gages traditionally used to determine changes in length, this has the advantage that not only changes in length in the micrometer range can be measured.
• - Capacitive: If the distance between two opposite electrodes or the density of the intervening dielectric is changed, the capacity of this structure changes. The evaluation can take place via classical bridge circuits.
• - Inductive: Magnetic fields are evaluated, which are emitted by a transmitter (eg electromagnet). The intensity of the received signals depends on the distance. In this type of measurement, the cables can be shielded so that external magnetic fields do not distort the measurement signal.
• - Optical: The distances to be measured are in the millimeter to a few centimeters range. In this area, it can be exploited that typical transmitting diodes (eg IR or UV) or LASER have a wide-angle beam characteristic which shows a strong gradient of the intensity in the propagation direction. This can be utilized in the near range in order to receive and evaluate the intensity dependent on the path length with photodiodes or transistors. Via series resistors, a voltage can be derived, which can be added directly to an analog / digital converter stage. The dependence of this voltage on the change in distance can be approximated in narrow ranges as proportional. If greater accuracy is desired, the values can be corrected with functions whose parameters result from the calibration process. The intensity gradient in the direction of propagation is further increased when the measuring layer is completely filled with a flexible material that acts optically diffusing, such as polyurethane or silicone mixed with eg titanium oxide. The homogeneous filling in particular simplifies the manufacture of a sensor cable and, viewed from the outside, results in relatively homogeneous cable properties. By using an opaque shell, the optical transmission is very robust against external interference and components and structure allow high long-term stability of the sensor properties.

• – Drucksensitiv: Dieser Sensortyp vermisst nicht wie die oben genannten Sensoren direkt eine Wegstrecke, sondern die Kräfte in der Kabelquerschnittsfläche, die durch Stauchung oder Dehnung hervorgerufen werden. Auch diese Sensoren können, wie alle zuvor beschriebenen Sensortypen, direkt auf einer helikalen oder mäanderförmigen Leiterfolie (Material der Trägerstruktur) aufgebracht werden. Diese könnte insbesondere Zungen oder Ausbuchtungen besitzen, die derart abknickbar sind, dass ihre Flächennormalen parallel zur Kabelmittelinie zeigen (siehe 4). Sie können aber auch wie die optischen Messstrecken angeordnet sein. In diesem Fall kann der Bereich, der sonst die Strecke zwischen Sender und Empfänger umgibt, mit einem anderen Elastomer gefüllt sein, das mit Metallfäden oder Graphit versetzt ist.

Other optical measuring methods are possible, eg TOF (Time of Flight), FPI (Fabry-Pérot interferometer) or FBG (Fiber Bragg grating).

• - Pressure-sensitive: This type of sensor does not directly measure a distance like the sensors mentioned above, but the forces in the cable cross-sectional area that are caused by compression or expansion. Like all sensor types described above, these sensors can also be applied directly to a helical or meander-shaped conductor foil (material of the carrier structure). This could in particular have tongues or bulges which are bendable in such a way that their surface normals parallel to the cable center line (see 4 ). But they can also be arranged as the optical measuring sections. In this case, the area which otherwise surrounds the distance between the transmitter and the receiver may be filled with another elastomer which is mixed with metal filaments or graphite.

Other measuring sections can be used: piezoelectric, acoustic, in particular ultrasound, magnetic inductive, in particular Hall sensors, microwaves, interference measurements, in particular laser interference measurements, pulse transit time measurements, pulse phase measurements, magnetostrictive distance measurement.

To determine or describe bends over a greater distance, the support structure may have two, three, four or more recesses. The narrower the recesses and the larger the number of recesses, the better the bending can be determined and thus resolved.

In a further embodiment, the sensor has a transmitter and a receiver, wherein in particular the receiver is a spatially resolving receiver. Depending on the location-resolving receiver used (e.g., PSD Photo Sensitive Device), the bend can be described mathematically. In the simplest form, the receiver detects only a signal (or no signal) and thus makes a statement as to whether the support structure is bent or not. Photodiodes, phototransistors or CCD detectors can also be used on the receiver side. At the transmitter side, diodes (e.g., IR or UV) or LASER can be used. It is also possible to use ultrasound transmitters and ultrasound receivers for path determination.

In a further embodiment, a single sensor has a microcontroller which evaluates a sensor signal, or the carrier structure has a plurality of sensors, which each have a microcontroller, which respectively evaluate sensor signals. Thus, the signals measured by the sensors can be directly evaluated and / or transported.

To reduce the number of microcontrollers, multiple sensors may have a common microcontroller. This is advantageous in particular when the microcontroller has a plurality of A / D converters and / or when the sensors are multiplexed to an A / D converter.

In a further embodiment, a single sensor has a signal conditioning or several sensors each have a signal conditioning. Thus, the signals of the sensors can be evaluated without providing external signal conditioning.

In order to realize the signal conditioning microcontroller side, the microcontroller may have an analog-to-digital converter. Thus, compact designs can be realized.

In another embodiment, two microcontrollers form a daisy-chain chain. Thus, the respective other microcontroller can be controlled, regulated and / or read out via a microcontroller.

To minimize line effects, a microcontroller can be placed close to the transmitter and receiver. In addition, transmitter characteristics such as latency can be affected.

In a further embodiment, a distance measured by the displacement sensor is less than 5.0 cm and greater than 0.001 cm, in particular the measured distance is less than 3.0 cm and greater than 0.003 cm, the distance corresponding in particular to the recess width.

To provide an alternative embodiment of the support structure, the support structure may be configured as a hinge. Thus, not only continuous bends can be detected, but also wrinkles, which take place via a joint.

In particular, the joint may consist of two segments of hollow balls of different radii. The radii of the hollow spheres can be chosen so that elements can be put on each other, so that a chain can be formed (see 5 ). The stacked balls act like a ball joint between two elements. Bends can be approximated along the chain. The balls can be equipped with groove guides in the axial direction to prevent torsion and to specify a maximum bending radius.

In each element can be mounted between the balls a board whose surface normal points in the axial direction of the element chain. On this board, the components for the realization of the measuring section are applied. Each on one side transmitter and on the other side receiver elements. Thus, measuring distances are realized by the balls. The boards can also carry additional components for the line connection.

The measuring sections can be bridged with different sensor technology (see previous versions). In contrast to the above example variant, in particular the measuring sections are longer here (with similar sensor properties). They are especially in the millimeter to centimeter range. When measuring without a hollow sphere, the measuring range can be up to 10 meters and more. Preferably then laser beams are used and for measuring PSD (Position Sensitive Device).

The measurement of a bend (also a bend) may be in the axial centerline. In an optical measuring system then suffices as a transmitter a single LED. As a receiver, a position sensitive photodiode (PSD) can be used. Since, with small ball sizes, the proximity effect (described above) can still be exploited, significantly cheaper photodiodes or transistors can also be distributed on the receiver side. These can subdivide the board into receiving sectors to distinguish bends in different directions. Since no compressions or expansions occur due to the rigid ball joints, two orthogonally arranged receiving sectors suffice to detect spherical distortions in the corresponding dimensions.

If more sensors are used, the additional information can be used to compensate for measurement inaccuracies. In order to keep the length of the measuring sections small, the transmitting diode can protrude from the circuit board and protrude further into the spherical center. If this projects beyond the center of the sphere, a lever results which increases the mechanical deflection of the diode. As a result, the measurement accuracy can be increased.

If more transmitting diodes are used, the axial center line of the elements can become free for a soul of a cable that can be equipped with various utility functions. This works especially when the bending radii are relatively small and so the soul does not protrude into the measuring sections.

If several laser beams are used for transmission, they can be guided in parallel in particular. To distinguish the different laser lines, these can be switched on and off with a time delay or have different wavelengths. If PSD elements are used on the receiver side, an axial torsion can be determined in addition to the bending.

In order to map the course in space for elongated structures, the support structure may have two, three, four or more joints.

In a further embodiment, one of the joints is guided, wherein in particular the guide is effected by means of a groove guide. Thus, torsion can be avoided and the number of sensors can be reduced.

In order to detect not only the shape of line-like objects but also the shape of area-like objects, the sensor cable may be in a sequence orthogonal to the axis. In particular, the sensors can be arranged in parallel.

For the measurement of sheet-like objects, the device can be realized as a grid in a further embodiment. This is especially in a plane when there is no bend. The support structure is also distributed in this plane and has recesses. The support structure is relatively rigid, so that bends and in-plane distortions in the plane change, in particular, the spacing of the recesses.

The support structure is divided into different areas that can move independently of each other. The connections for power supply and information exchange can again meander and helically connect these areas (see 6 above). Above the recesses there are measuring sections in the above mentioned possibilities (see 6 Center). Not every carrier structure area has to carry a microcontroller. Lines for driving and reading the measuring sections can be grouped so that they can address in combination a particular area of the support structure. In particular, given a Cartesian grid, leads can be routed as columns and rows.

As with the sensor cable described above, this arrangement can be used to measure bends when a reference plane is introduced which is parallel to the measurement plane and does not allow distortion of the grating structures. The sensor cable is the same as the distortion-free cable centerline. Bends then cause a leverage that shifts individual areas of the carrier layer against each other. The disadvantage here is that with a distortion-free reference plane only one global bending direction can be allowed (as in a metal sheet).

In another embodiment, the regions of the carrier layer are freely displaceable. Thus any deformations can be detected. If, in particular in the case of an optical measurement, the rotation of the transmitter and receiver components is not relevant metrologically by the wide-angle characteristic of the components and the diffusion effect of the potting medium, in particular the spacings between the carrier structure regions are measured. From the measured spacings, a three-dimensional model of the shape of the shape sensor can be calculated. However, this calculation is underdetermined because it can not be deduced from the data whether differences in the direction of the surface normal of the sensor point in its direction or in the opposite direction. This requires additional information, which can be detected in particular by angle sensors. Angle information can also be detected, for example, by a second measuring path, which is arranged offset in the direction of the surface normal of the sensor (see 6 below). In order to form a simple and practical form of the support structure, the support structure can be designed as a helix or meander shape.

In a further aspect of the invention, the object is achieved by a device which has a previously described support structure. In this case, the support structure can be wrapped around a structure or be manufactured part of the device.

To use the invention as widely as possible, the device may be configured as a cable, a hose, a conductor foil, an endoscope, a garment, a tire, a cloth, a fabric, a grid or a pad. With all these devices, the position in space can be determined.

In particular, the structure may be formed as a polygon "soul" so that, for example, cables with a circular or oval cross-sectional area can be provided. Polygonic souls include triangular, quadrangular, or polygonal cross-sectional faces. In this case, for example, the soul can be made hollow and lead more cables or fluids.

In a further embodiment, the device or the support structure has a supplementary sensor, in particular an inertial sensor, gyrosensor or compass sensor. Thus, supplementary position data can be determined for comparison.

In order to determine additional information about position and movement, the device or the support structure may additionally comprise an inertial sensor, gyrosensor or compass sensor.

As additional sensors for further sizes, the device or the support structure may be u.a. Sensors for measuring the (outer) light intensity - including infrared and also as camera image information, the (external) printing properties, the sizes for operating proximity sensors, the electromagnetic field strengths, the vibrations, the pH, and / or the temperature. In particular, the temperature is an important information that can be used to compensate for the temperature dependencies of the measuring sections. Typically, such a sensor is provided in the microcontrollers so that regional measurements can be made.

In a further embodiment, the device or the carrier structure has an actuator. Thus, not only the position (in space) can be determined, but it can additionally be a controlled / regulated changing the bending in space by means of the actuator. Multiple actuators can be used to bend in both dimensions. If these are then also used repeatedly in axial length or in the surface, complex shapes can be adjusted in the room.

In order to protect the device against axial torsion, parts other than the support structure may be made torsionally rigid. This can be done, in particular, by designing the core of a cable such that torsions are not possible, e.g. by cardan joints for each winding / meander section. Furthermore, the sheath of a cable can be designed so that torsions are not possible, e.g. by a braid of metal or plastic, an expanded metal shell, a corrugated tube made of metal or plastic or by the previously described ball elements (joint support structure). In addition, the cable can be sewn or welded into other materials so that a torsion is no longer possible or the torsion is constant or known and can be taken into account in the evaluation.

In another embodiment, the axial torsion is detected and modeled explicitly. This can be done by a special torsion sensor. In particular, by additional measuring sections, which are arranged along the cable profile and measure torsion there.

In particular, a skew of the measuring section can be used to measure both an axial distance and a distance in the profile. For modeling, both directions should be separated from the information. In particular, additional measuring sections may be given in another inclined position. In particular, an orthogonal arrangement of paired measuring sections.

In order to avoid over-bending of the sensor, a restriction of the bending freedom can take place in the middle of the cable. In particular, ball or cardan joints may have a stop limit. Due to the greater leverage effect, however, a bending radius limitation is to be accommodated more material-efficiently in the jacket. Even there limit stops can be realized. In particular, interlocking profiles may be used, e.g. Agraffprofile.

In order to use the device in dusty or other inhospitable conditions, the sensor and / or the microcontroller and / or the joint dust, water and light can be configured.

The spatial structures of the electrical circuit of the sensor have a complex character, e.g. helical or meandering. Conventional measures can be taken to make the arrangement fail-safe, in particular a low-impedance termination of the bus system. Bus drivers can be used for longer cable lengths. The interior space can be kept field-free with respect to external electric fields by using an electrically conductive sheath.

In a further aspect of the invention, the object can be achieved by a daisy-chain circuit, which in particular has a previously described carrier structure, with a first microcontroller and a subsequently arranged second microcontroller, wherein the two microcontrollers are connected via a bus, above also can be addressed directly and at least one sensor is connected to the microcontroller, wherein the first microcontroller controls or regulates the downstream microcontroller.

Thus, on a support structure, a circuit arrangement can be applied, which is easy to read and which is easy to program.

In order to provide a daisy chain circuit over the entire extent of the carrier structure, further microcontrollers which are respectively connected to the previous microcontroller and which each control or regulate subsequent microcontrollers can be provided. It can be communicated in both directions. In particular, when the microcontrollers are connected via tri-state ports, both may be configured as an input port by default. Only when information is to be transmitted is one of the ports reconfigured as output.

In a further refinement, the sensor has a transmitter and a receiver, wherein the transmitter can be switched on and off in a microcontroller-controlled manner. As a result, an energy-saving daisy-chain circuit can be provided. In particular, the driving behavior of a transmitter can be taken into account. The transmitters do not have to be constantly in operation, but can be switched on for local measurements - and then off again to save energy. The (analog) receiver elements need some time after switching on the transmitter to reduce transients. With temporal properties of selected components, it is thus sufficient if the transmitters are turned on by the upstream microcontroller and then turned off again in the next but one cycle.

For devices with support structure that is very favorable, because there transmitter and receiver can be on different turns / meanders of the conductor foil (support structure) - or on different boards. Thus, the transmitter can be placed in the vicinity of the switching microcontroller and it can be omitted lines along the conductor foil.

In order to realize an optimized programming of the microcontroller on the carrier structure, the microcontroller can be reprogrammed by means of the controller.

The programming of the microcontroller can be done before the assembly on the printed circuit boards or boards. However, if the function is to be optimized later, it is imperative that the microcontrollers can also be programmed when installed. Parallel programming is not possible with marketable microcontrollers because they send individual feedback to the programming device. The programming then takes place individually sequentially. The activation of the programming mode can be done by the respective upstream microcontroller, which receives the information on the signal transmission again. The data is then written by a central programmer over the serial bus (which is otherwise used for data output) to the microcontroller. For this programming method, the manufacturer-side programming is still extended to the selection process.

In a further aspect of the invention, the object is achieved by a conductor foil, which has a previously described daisy-chain circuit. The conductor foil can be wound, for example, around a structure or run meandering on the structure.

In a further embodiment, the conductor foil is rigid and / or flexible. A rigid form is, for example, a joint, a flexible is a flexible film or the support structure described above.

To effectively provide previously described devices, the conductor foil is part of a previously described device.

In a further embodiment, the temperature in the vicinity of the measuring sections is detected by each microcontroller. This is especially important because many of the above-mentioned meter versions are temperature dependent and so compensation can be made.

In a further aspect of the invention, the object is achieved by an optical sensor for determining a distance, the sensor having a transmitter and a receiver and the transmitter having a sufficiently wide-angle radiation characteristic, the distance being from 0.01 cm to 5.00 cm, in particular from 0.01 cm to 3.00 cm or in particular from 0.03 cm to 1.50 cm, and the transmitter is designed in particular as a light-emitting diode.

Thus, a novel displacement sensor can be provided. The wide-angle radiation characteristic results in a strong intensity gradient of the light along the measurement path. This can be used to make a distance measurement. Furthermore, in a relevant embodiment, the measuring path has a diffusion layer which further increases the wide-angle radiation characteristic of the optical transmitter and provides an even greater intensity gradient. In particular, in devices described and in support structures, the respective measuring sections may be filled with a material (e.g., polyurethane or silicone mixed with titanium oxide) which forms the diffusion layer. The illumination and reception cones can be set so wide that low rotations of a transmitter or receiver element makes no significant difference in measurement. This independence is important because bends in one plane cause rotations of the gauge elements in the other bending plane. These can be neglected with this displacement sensor.

When bending a portion of the diffusion mass is pushed out of the range of the measuring section in compressed areas, while stretching part of the surrounding diffusion mass is drawn into the region of the measuring section. Both support the effect of the intensity gradient during movement.

So that not only distances can be measured with the displacement sensor, but also bends, it is essential that a bend with a lever effect is translated into a change in distance. In the case of the sensors described, this is done by the radial and / or orthogonal distance with respect to an ideal center line or a reference plane.

In a further aspect of the invention the object is achieved by a device, in particular a cable-like structure, wherein a position of the device is determined by measurement in a room, wherein the information for the position within the device is determined.

Thus, in the case of a cable, the position information in the soul or within the measuring layer is determined. Measurement information outside the shell is not required.

The described cable sensors detect three-dimensional bearing characteristics by detecting bends in two planes. For certain evaluation, it may be sufficient to detect bends in only one plane, e.g. for detecting wing bends.

Furthermore, the invention will be explained with reference to exemplary embodiments. Show it

1 a schematic representation of a cable with a measuring layer,

2 a schematic representation of a cable with a wrapped support structure and optical transceiver devices,

3 a schematic representation of a bent cable with wrapped (curved) support structure,

4 a schematic representation of a cable with incorporated support structure and orthogonally arranged pressure sensors,

5 a schematic sectional view of a ball joint with optical transmitting and receiving unit,

6 a schematic representation of a surface shape sensor with two-dimensional support structure with connections and measuring sections (top), distance measurement with a measuring section (center), distance measurement and angle measurement with two measuring sections (below) and

7 a schematic block diagram of an evaluation.

In addition, the invention of the structure of a cable by means of 1 to 4 explained in more detail.

Basically, a cable is symmetrical about a centerline 1 built up. In the middle is the so-called soul 2 which comprises, for example, the optical conductor in an optical waveguide. According to the invention, a measuring layer follows from the inside to the outside 3 , which paraxial to the center line 1 runs. To avoid axial torsions is a steel braid 4 fits. The outer coat 5 consists of an agraff profile, which A bending radius limitation allows and ensures that even under mechanical stress, the cable profile always remains circular. The outer layers 4 and 5 are made of metal and thereby prevent the emission of electric fields or the interference of an external electric field.

In the following the measuring layer becomes 3 explained in more detail. The support structure is through a wound conductor foil 6 educated. The shape of the conductor foil 6 is helical. The interstices are covered with a transparent elastomer 3 filled with diffusion particles of titanium oxide. On both sides of the spaces are a light emitting diode 7 ( 2 .) And a phototransistor 9 ( 2 .) arranged. The measuring distance 8th ( 2 .) of light emitting diode 7 ( 2 .) and phototransistor 9 ( 2 .) corresponds approximately to the gap. led 7 ( 2 .) and phototransistor 9 ( 2 .) form an optical sensor. Such a sensor is provided every 90 °, so that for each degree of freedom both a compression information and a strain information is determined. Such a quad array of sensors is mounted multiple times along the entire cable.

The geometry of a curved conductor foil 6 is in 3 to see. The unwound conductor foil has the width L. The pitch angle γ of the winding results in an axially effective conductor foil width: l = L / cos γ. A segment s should consist of the effective conductor foil width l and a distance a: s = a + l. Since the segments should be small compared to the bending radius r, all axial lengths are approximated with arc lengths along the bending curvature, which reduces the computational effort.

Should a finer modeling be necessary, also effects of compression and elongation are considered.

The arc length of a segment is given by: s = φr. Here φ describes the included angle in radians. The arc length at the inner bending side is s _i = φ (r - D / 2) and at the outer bending side: s _a = φ (r + D / 2). D describes the coil diameter. With an ideal sensor setup, the distance along the center line remains unchanged: a ₀ = s ₀ -l. For the distance at the inner bending side we get: a _i = φ (r - D / 2) - l and at the outer bending side: a _a = φ (r + D / 2) - l. The distance therefore absorbs all length changes of a segment during bending, since the effective foil length remains constant.

This is applied so that the measuring section 8th ( 2 .) of the cable when bending changes. This is done by measuring the distance of the measuring section 8th ( 2 .) along the entire cable. The individual data and values are transmitted to a computing unit on a bus system and, starting from a known point of the cable, the orientation in space is modeled.

The bending of the cable is alternatively pressure-sensitive by means of a pressure sensor 8th ( 4 .). The forces in the cable cross-sectional area, which are caused by compression or expansion, are determined. Also these pressure sensors 8th ( 4 .) are placed directly on the wound conductor foil 6 applied. These have tongues / bulges 7 ( 4 .), which are bent so that your surface normal parallel to the cable middle line 1 demonstrate.

Another alternative is in 5 shown. There, a kink in a ball joint is determined. The ball joint consists of two segments of hollow balls 1 different radii. The radii of the hollow spheres 1 are chosen so that ball joints can be put on each other, so that a chain is formed.

Bends can be approximated along the chain. The hollow spheres 1 are with guide pins 2 and groove guides 3 equipped in the axial direction, so that a torsion is prevented. In each ball joint is between the hollow balls 1 a circuit board 4 fastened, the surface normal in the axial direction of the ball joint chain shows. On this board 4 are stations 7 and receiver 6 applied to the displacement sensor, wherein the displacement sensor, the distance of the measuring path between the transmitter 7 and receiver 6 certainly.

Thus, measuring distances are realized by the balls. Alternatively, the boards have additional components 5 for the line connection. These are designed as a bellows or alternatively elastic to accommodate the bend. They pick up or keep the connection lines between the boards outside the measuring range. The compounds are helical or alternatively meandering in or outside the component 5 guided.

The measuring distances between the transmitters 7 and the recipients 6 can be determined with all described displacement sensors, wherein in the present case an optical sensor is used. The resolution of the optical sensor is in the millimeter to centimeter range.

In the present case, the optical detection will be described. The measurement takes place in the axial center line. The transmitter is a single LED 7 used. The receiver is a position-sensitive photodiode (PSD). Since the proximity effect (distribution of the LED beam characteristic) is exploited for small ball sizes, they are used alternatively the receiver side also significantly cheaper photodiodes or transistors 6 distributed. These then divide the board X into receiving sectors to distinguish bends in different directions.

The LED is mounted so that it reaches just before the receiving elements. The connections then extend transversely through the ball housing and thus form a lever that causes a large movement in front of the receiving elements in response to the ball joint rotation.

Since no compressions or expansions occur due to the rigid ball joints, two orthogonally arranged receiving sectors suffice to detect spherical distortions in the corresponding dimensions.

If multiple sensors are used, the additional information is used to compensate for measurement inaccuracies.

When using several transmitter diodes 7 , the axial center line of the elements becomes free for a soul equipped with various utility functions. This works because with relatively small bending radii the soul does not protrude into the measuring sections.

Another alternative is in 6 shown. There is the carrier structure 1 given in a grid shape. The individual areas are with meandering tracks 5 flexibly connected. A distance measurement between the areas is done with measuring distances 3 realized, being a transmitter 2 is given on a support structure and a receiver 4 on the opposite area of the support structure. In addition to the optical measuring sections, other previously described measuring sections can be used, in particular resistive.

The data from the distance measurements does not completely determine the three-dimensional shape. In addition, information is still necessary in which direction a bend exists. These can be provided with a second measuring path, which is provided below the support structure. The height offset of the components results in each case a lever relative to the plane of the support structure. The illumination characteristics are again shown here as narrow cones. In fact, they are much more angular. Together with the effect of the diffusion mass results in virtually no change when a (transmitter or receiver) element is rotated slightly. Essential are the distances that can be precisely measured with this arrangement. For each of the two transmitting diodes two length measurements can be made to the opposite elements. If there were no lateral offset of the support structure regions, the calculation of the two-dimensional arrangement would already be overdetermined with these four measurements. Thus, the three-dimensional information must be calculated from a regional model.

The electronic interconnection of the components described is in 7 shown as a block diagram. There is a (host) computer 1 which may be part of the desired application. It converts the data of the measuring sections into the desired information. In particular, local bending angles are calculated in an intermediate step. This information is then available for the entire axial length.

In particular, the bending angles are used to visualize the spatial characteristics. This is done with conventional visualization environments such as e.g. DirectX or Java3D, which make it possible to represent (sub) segments of the support structure in a virtual space. At the end, a new coordinate system is assigned to which the following (sub-) segment is bound. The coordinate systems are then parameterized with the associated local bending angles. This makes an overall presentation easy.

For monitoring applications, the values of the local bending angles are monitored. In particular, this is possible in a simple case by specifying local threshold values. In a further embodiment, any combinations of bending angle characteristics are monitored. The default is typically done by pattern combinations with the desired output result. In order for the system to produce similar outputs even for bend angle combinations that are only similar to the pattern combinations, conventional pattern recognition techniques, such as those described in U.S. Pat. SVM (Support Vector Machines) are used, which realize these desired generalization properties.

The (host) computer 1 is via a serial connection 24 with the programmer 2 connected. Alternatively, this can also be another (host) computer, which then runs the development environment for the microcontroller. The microcontrollers are programmed via a serial bus 7 eg by SPI. Each of the three microcontrollers shown 4 - 6 is on the bus 7 with the taps 11 - 13 connected.

For programming, most microcontrollers use a dedicated input port, which is set active for this purpose. In the present case, this does not take place via the connecting lines of the carrier structures since a separate connection would have to be realized for each microcontroller. This input port for programming is operated directly by the upstream microcontroller. That's what the wires are for 15 . 16 and 17 intended. The upstream microcontroller "knows" from a special memory configuration, which is written into the module during programming, that it itself has just been programmed and now the next microcontroller is to be programmed. In order for the programming device to set the right time, there is also a global signaling line 14 with the taps 21 - 23 , To initiate all programming is done by microcontroller 3 a switch 15 actuated.

microcontroller 3 has a special job. Via the data bus 7 he reads the readings of the local microcontroller 4 - 6 and submit it to the (host) computer 1 over the serial connection 25 further. He also takes over the control of the selection of the measuring microcontroller. This is done via the selection lines 18 - 20 , which allows a read-out function in the daisy-chain method. In this variant, the transmitters of the measuring sections are also the same via these lines 8th and 9 activated. In this embodiment, they are connected by the selection signal of the upstream microcontroller. The measuring sections then have to reduce transient time before the actual measurement. In another embodiment, the transmitters are also connected to an output port of a local microcontroller. Is an evaluation cycle eg of the microcontroller 5 If so, it notifies the next microcontroller 6 about the connection 20 , The global clock is determined by the microcontroller 3 via the programming line not required at runtime 14 and their taps 21 - 23 , In another embodiment, this is also done via a separate connection.

An evaluation cycle involves the conversion of the sensor values of the measuring sections 8th and 9 from analog to digital values and passing on this information via the taps 11 - 13 on the bus line 7 to microcontroller 3 that you (host) computer 1 about the connection 25 provides. This connection is a typical computer interface, such as USB, Firewire, Ethernet. The circuit in 6 is continued to the right of other microcontrollers, their wiring and function of the microcontrollers 5 and 6 equivalent.

Claims (10)

Support structure for measuring a bending, wherein the support structure has a first recess with an axial spacing and / or a second recess with a Orthogonalbeabstandung, so that upon bending of the support structure substantially a change of the axial spacing and / or the Orthogonalbeabstandung occurs, characterized in that the Axialbeabstandung and / or the Orthogonalbeabstandung metrologically by a sensor, in particular a displacement sensor or a pressure sensor is bridged. Support structure according to claim 1, characterized by two, three, four or more sensors. Support structure according to claim 2, characterized in that the two, three, four or more sensors, supply technology, metrology, control technology, control technology and / or information technology, in particular by means of a bus system, are interconnected. Support structure according to claim 3, characterized in that the connection between two or more sensors is designed helical or meandering. Support structure according to one of the preceding claims, characterized by two, three, four or more recesses. Support structure according to one of the preceding claims, characterized in that the sensor comprises a transmitter and a receiver, wherein in particular the receiver is a spatially resolving receiver. Support structure according to one of the preceding claims, characterized in that the support structure is designed as a joint or has a joint. Support structure according to claim 7, characterized in that two, three, four or more joints. Support structure according to one of claims 1 to 8, characterized in that the support structure is designed as a helix or meandering. Device having a support structure according to one of the preceding claims.

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