ENVELOPING BODY AND METHOD FOR DETECTING A CONTOUR OF AN AMPUTATION STUMP

Abstract

The invention relates to an enveloping body for at least partially recording a contour of a limb, wherein the enveloping body has a base body, and at least one sensor that is configured to record measurement data which can be used to determine a distance and/or relative position between two points in or on the base body.

Claims

1. An enveloping body for at least partially recording a contour of a limb, wherein the enveloping body has a base body, characterized in that the enveloping body has at least one sensor that is configured to record measurement data which can be used to determine a distance and/or relative position between two points in or on the base body.

2. The enveloping body according to claim 1, characterized in that the sensor has a transmitter for a measuring radiation and a receiver for the measuring radiation, which are arranged in such a way that the measuring radiation emitted by the transmitter is at least partially received by the receiver.

3. The enveloping body according to claim 2, characterized in that the transmitter and the receiver are located at a first point, the enveloping body further comprising a reflector for the measuring radiation which is located at a second point, or alternatively that the transmitter is located at the first point and the receiver at the second point.

4. The enveloping body according to claim 3, characterized in that the measuring radiation is electromagnetic radiation, in particular visible light, radar radiation and/or X-rays, magnetic radiation, for example in the form of an alternating magnetic field and/or sonic waves, such as ultrasonic waves.

5. The enveloping body according to claim 3, characterized in that the enveloping body comprises more than one receiver and/or more than one reflector.

6. The enveloping body according to claim 1, characterized in that the at least one sensor comprises a strain sensor, in particular a strain gauge, an electroactive polymer and/or a fiber Bragg element.

7. The enveloping body according to claim 1, characterized in that the at least one of the sensor is a shape sensor.

8. The enveloping body according to claim 1, characterized in that the enveloping body features a communication interface by means of which the measurement data recorded by the at least one sensor can be transmitted to an electronic data processing device, in particular a micro-processor.

9. The enveloping body according to claim 1, characterized in that the base body is made from an elastic material.

10. The enveloping body according to claim 1, characterized in that the enveloping body is a prosthesis liner and the base body is made of a liner material.

11. A method for at least partially recording a contour of a limb, wherein the method comprises the following steps: mounting an enveloping body according to claim 1 on the limb, recording measurement data by means of the at least one sensor, determining distances and/or relative positions between two points in or on the base body in an electronic data processing device.

12. The method according to claim 11, characterized in that a manipulation of a shape of the limb occurs during at least a part of the process of recording the measurement data.

13. The method according to claim 11, characterized in that distances and/or relative positions between at least 10 points, at least 20 points, at least 50 points, or at least 100 points are detected.

14. The method according to claim 11, characterized in that the recording of the measurement data is continuous or triggered automatically when the enveloping body is deformed from the outside.

15. An enveloping body for at least partially recording a contour of a limb, wherein the enveloping body includes: a base body; at least one sensor; and a communication interface; wherein the sensor further comprises a transmitter and a receiver, the sensor being configured to record measurement data which can be used to determine a distance and/or relative position between first and second points in or on the base body of the enveloping body, and wherein the communication interface further comprises an electronic data processing device.

16. The enveloping body of claim 15, wherein the transmitter and the receiver are arranged on the enveloping body such that a measuring radiation emitted by the transmitter is at least partially received by the receiver.

17. The enveloping body of claim 16, wherein the transmitter and the receiver are located at a first point on the enveloping body, and wherein the enveloping body further includes a reflector located at a second point on the enveloping body.

18. The enveloping body of claim 16, wherein the measuring radiation emitted by the transmitter is electromagnetic radiation, visible light, radar radiation and/or X-rays, magnetic radiation, and/or sonic waves, such as ultrasonic waves.

19. The enveloping body of claim 15, wherein the enveloping body includes more than one receiver and/or more than one reflector.

20. The enveloping body of claim 15, wherein the at least one sensor is a strain sensor, such as a strain gauge, an electroactive polymer and/or a fiber Bragg element.

Description

[0037] In the following, some examples of embodiments of the present invention will be explained in more detail by way of the attached figures: They show:

[0038] FIGS. 1 to 4—various embodiments of an enveloping body according to an example of an embodiment of the invention as a prosthesis liner, and

[0039] FIGS. 5 to 8—various embodiments of an enveloping body according to an example of an embodiment of the invention as a bandage.

[0040] FIG. 1 shows an enveloping body 1 according to a first example of an embodiment of the present invention in the form of a prosthesis liner. It has a main body 2 made of a liner material. The liner material contains several optical fibers 4 into which fiber Bragg sensors 6 are incorporated. The optical fibres 4 converge at a distal end 8 of the liner and can be exposed to light by an interrogator 10. This is preferably done one after the other. The individual fiber Bragg sensors 6 exhibit characteristic behaviour as optical interference filters. They absorb light of a certain wavelength, this wavelength depending on the strain or mechanical tension of the fiber Bragg sensor 6, as previously explained. In particular, in the event that the individual fiber Bragg sensors 6, which are interconnected by a single optical fibre 4, are designed differently and have different absorption spectra, they can be interrogated successively or even simultaneously. To this end, it is advantageous, for example, if the fiber Bragg sensors 6 that are closer to the interrogator 10 do not absorb electromagnetic radiation that is absorbed by fiber Bragg sensors 6 that are connected by the same optical fibre 4 but further away from the interrogator 10. If the fiber Bragg sensors are subjected to mechanical stress or strain, the center frequency in particular, which is also known as the Bragg frequency, is displaced in a known manner so that the strain can be inferred. Since the order of the individual fiber Bragg sensors 6 along the optical fibers 4 cannot change, the different strains can also be used to infer the contour of an amputation stump which is located within the prosthesis liner but is not shown in FIG. 1.

[0041] The interrogator 10 interrogates the individual fiber Bragg sensors 6 and transfers the measured data to an electronic data processing device 12 in which the actual evaluation takes place.

[0042] FIG. 2 shows a different configuration of the prosthesis liner 1. There is a transmitter 14 in the vicinity of the distal end 8 which emits a measuring radiation. In the example shown, these are ultrasonic waves. These are reflected by reflectors 16 and travel along arrows 18 back to the sensor, which also contains a receiver. The measurement data is then transferred to the electronic data processing device 12 and evaluated.

[0043] The advantage of ultrasonic waves in particular is that they are coupled by the transmitter 14 into the soft tissue of the amputation stump and expand in it. It is not necessary to ensure that the ultrasonic waves propagate through the liner material, which can be an elastic silicone material, for example. The transmitter 14 can, for example, transmit in continuous operation or emit its measuring radiation in the form of pulses. A rotating transmitter 14 can also be used, wherein the transmitter 14 itself does not necessarily have to rotate; rather, only the emitted measuring radiation is emitted in different angular ranges, which preferably rotate. The measuring radiation, i.e. the ultrasonic radiation in this example, strikes the reflectors 16 and is reflected back by them and reaches the receiver, which is not shown separately in FIG. 2. In this way, the distances of the individual reflectors 16 from the transmitter 14 can be determined via time-of-flight measurements. However, it is disadvantageous that ultrasonic signals in particular can be reflected at boundary surfaces and bony components of an amputation stump also provide a signal.

[0044] FIG. 3 shows another configuration of the prosthesis liner 1. There is a transmitting coil in the area of the distal end 8, said transmitting coil being supplied with alternating current and emitting an alternating magnetic field 20. This is also preferably designed to rotate, so that the main transmission direction of the transmitter 14 also changes. Inside the liner material of the base body 2 of the prosthesis liner are receivers 22 in the form of receiving coils, which are connected to the distal end 8 via electrical lines 24. The alternating magnetic field 20 induces an electric current and an electric voltage in the receivers 22, which can be tapped and measured via the electrical line 24. The magnitude and phase of the electric current and/or voltage induced in the receivers 22 depends on both the distance of the receivers 22 from the transmitter 14 and the orientation and direction of the receiver 22 relative to the transmitter 14. This measurement data is then transferred to the electronic data processing device 12 and evaluated.

[0045] FIG. 4 shows another embodiment of the prosthesis liner 1 in which strain sensors in the form of strain gauges 26 are arranged in the form of a mesh. In the example of an embodiment shown, they form a square grid with intersection points 28, wherein a strain gauge 26 is located between every two intersection points 28. An enlargement of this arrangement is shown in the right-hand area of FIG. 4. If the prosthesis liner is now pulled over an amputation stump, it stretches in some places more than others, depending on the shape of the amputation stump. Electrical lines 24, which are shown in the right-hand part of FIG. 4, can be used to apply electrical current and/or voltage to the individual intersection points 28. An electronic data processing device 12 controls this process. By applying an electrical voltage, the strain gauge 26 located between the two specified crossing points 28 is measured and the measurement signals thus obtained are evaluated by the electronic data processing device 12. Since the neighbourhood relations of the different strain gauges 26 and also the intersection point 28 are known and cannot change, a detailed picture of the contour of the prosthesis liner can be determined from the knowledge of the respective distances between two neighbouring intersection points 28. The denser and tighter the mesh, the more detailed and better the image of the contour.

[0046] FIGS. 5 to 8 depict various embodiments of the enveloping body 1 in the form of a bandage. The function of the bandage according to FIG. 5 corresponds to that of the prosthesis liner according to FIG. 3. The distal area again shows the transmitting coil that emits the alternating magnetic field 20. Again, there are receivers 22 inside the main body 2, which are connected to a distal end of the bandage via electrical lines 24. The alternating magnetic field 20 induces an electric current and an electric voltage in the receivers 22, which can be tapped and measured via the electrical line 24.

[0047] The function of the bandage according to FIG. 6 corresponds to that of the liner according to FIG. 4. The bandage shown in FIG. 6 also has a network of strain gauges 26 arranged between intersection points 28. Electrical wires 24 which cross at the intersection points can apply an electrical current or voltage to the individual strain gauges 26.

[0048] The function of the bandage according to FIG. 7 corresponds to the function of the prosthesis liner according to FIG. 1. Fiber Bragg sensors 6 are interconnected by optical fibres 4, which are brought together at a distal end 8.

[0049] The function of the bandage according to FIG. 8 corresponds to that of the liner in FIG. 2. The transmitter 14 is situated in the vicinity of the distal end 8, wherein said transmitter emits the measuring radiation, which in the example of an embodiment shown may be ultrasonic waves, for example. These are reflected along the arrows 18 by reflectors 16, which in the example of an embodiment shown represent interfaces between two different materials, and conveyed back to the transmitter. Since the transmitter also contains a receiver, measurement data can be evaluated and transferred.

REFERENCE LIST

[0050] 1 enveloping body [0051] 2 base body [0052] 4 optical fiber [0053] 6 fiber Bragg sensor [0054] 8 distal end [0055] 10 interrogator [0056] 12 electronic data processing device [0057] 14 transmitter [0058] 16 reflector [0059] 18 arrow [0060] 20 alternating magnetic field [0061] 22 receiver [0062] 24 electrical line [0063] 26 strain gauge [0064] 28 intersection point