SENSOR DEVICE

Description

[0001] The invention relates to a sensor device comprising at least two sensors and a base body with an upper part and a lower part and at least one elastic element arranged between the upper part and the lower part.

[0002] Such sensor devices are known from the prior art, for example, EP 2 341 410 A1. WO 2020 / 041491 A1 describes, for example, such an arrangement that is installed in an orthotic device, such as a connecting element for joining two prosthetic components. The device has an upper part on which a conventional pyramid adapter for connecting to another prosthetic component is located. The lower part is designed as a plate-shaped element and is connected to the upper part via a centrally located bridge. This allows the upper part to tilt relative to the lower part if the central bridge is deformed. Sensors are arranged at the outer edges of the upper and lower parts, respectively, which can measure the distance between the upper and lower parts. This allows the angle between the upper and lower parts to be determined.This angle is caused when different forces act on opposite sides of the bridge. A disadvantage is that the small deflection necessitates very precise sensors, and the deflection limits are reached quickly.

[0003] A similar device is known from WO 2021 / 040998 A1. It features a frame that is inherently deformable when forces are applied to it. This device is also intended for use in orthotic devices. It has a base that supports the pyramid adapter for connecting to other prosthetic components and forms the lower part. This base has a medially to laterally extending projection on which the frame forming the upper part rests. Anterior and posterior to this projection, there is a small gap between the upper and lower parts, allowing the upper part to move under the influence of forces, with this movement causing deformation of the upper part. In this design, only forces that lead to deformation of the upper part can be determined.

[0004] US Patent 8,746,080 B2 discloses a connection device for orthotic devices that includes a pyramid adapter with a cavity. Under high loads, this causes deformation of the adapter and thus of the cavity, which can be measured by distance sensors. Here too, the forces must cause deformation of the upper part, formed by the top of the adapter, in order to be measured.

[0005] The invention is therefore based on the objective of eliminating or at least reducing the disadvantages of the prior art.

[0006] The invention solves the stated problem by means of a sensor device according to claim 1.

[0007] Unlike prior art embodiments, in the embodiment according to the invention the upper part can also be displaced relative to the lower part along the preferred direction, preferably without deformation of the upper part. The at least two sensors are configured to determine a distance between the upper and lower parts, and this occurs at two different locations. In advantageous embodiments, more than two, preferably more than three, and particularly preferably more than four sensors are provided, each determining a distance between the upper and lower parts. The positions at which this occurs are preferably arranged such that they do not lie in a straight line.

[0008] The sensors do not need to be able to quantitatively determine the distance between the upper and lower parts, although this is a preferred embodiment. For the invention to function, it is sufficient if each sensor is able to determine whether or not there is a gap between the upper and lower parts at its position. Therefore, such a sensor can, for example, be designed as a contact sensor or pressure sensor, or be another type of sensor that can detect whether the upper part is in contact with the lower part.

[0009] Preferably, the size of the distances between the upper and lower parts is known for each individual sensor in the unloaded state. This corresponds to a zero position. The individual distances do not need to be the same for all sensors in the unloaded state. However, it is advantageous if they are. If a force now acts on the upper and / or lower part, causing movement of the upper part relative to the lower part, at least some, but usually all, of the distances between the upper and lower parts measured by each sensor will change. If all distances change equally, this means that the upper and lower parts have moved towards each other without the orientation of the upper part relative to the lower part changing. This is therefore a displacement along the preferred direction.

[0010] However, if the distances between the upper and lower parts change in different ways at different positions, the orientation of the upper part relative to the lower part also changes. This is consequently a tilting about the tilting axis. Of course, superpositions of the two movements are also possible, for example, if all distances between the upper and lower parts detected by sensors decrease, but by different amounts.

[0011] In the inventive embodiment of the sensor device, unlike in the prior art, it is not the upper or lower part that is deformed, but preferably an elastic element arranged between them. Preferably, more than one elastic element, for example two, three, or four elastic elements, are present, which are deformed when the upper part moves relative to the lower part. It is not necessary for all elastic elements to be deformed with every movement. The elastic elements are arranged such that the magnitude and type of deformation that has occurred in the elastic elements can be determined from the measurement result of the sensors that determine the distance between the upper and lower parts. The spring constants, i.e., the relationship between the deformation of an elastic element and the force resulting from it, are preferably known for all spring elements.This relationship is also called the spring constant even if the relationship is not linear. Knowing all these quantities, the magnitude and direction of the force acting on the sensor device can then be determined.

[0012] The use of at least one elastic element allows for greater displacements and / or tilting of the upper part relative to the lower part across the force and / or moment range to be measured than is possible with prior art designs. This also allows the use of sensors with lower resolution and measurement accuracy, which are generally more cost-effective. Sufficient mechanical stability of the sensor assembly is preferably ensured by end stops, upon reaching which large forces and / or moments can be transferred from the upper part to the lower part without subjecting the at least one elastic element to excessive stress.

[0013] In In a preferred embodiment, at least one elastic element offers a different resistance to a tilting of the upper part relative to the lower part in a first tilting direction than to a tilting in a second tilting direction. This is advantageous, for example, when the expected forces and / or the resulting and generated torques differ in magnitude in different tilting directions.

[0014] Preferably, the upper part is displaceable relative to the lower part along a plane of symmetry of the base body, more preferably a plane of symmetry of the sensor device. The sensor device is preferably used in an orthotic device, for example, an orthosis or a prosthesis, to determine the forces and torques occurring there. The plane of symmetry of the base body, or preferably the plane of symmetry of the sensor device, is then preferably arranged such that it corresponds to a frontal or sagittal plane of the wearer of the orthotic device. The preferred direction along which the upper part is displaceable relative to the lower part and which lies in the plane of symmetry, then preferably extends from proximal to distal.

[0015] Preferably, the tilting axis lies in the plane of symmetry. The plane of symmetry is then preferably defined by the tilting axis and the preferred direction.

[0016] Advantageously, the at least two sensors are located on opposite sides of the plane of symmetry and preferably at the same distance from this plane. This makes it particularly easy to calculate the forces acting on the sensors from their distance measurements. If the tilting axis does not lie in the plane of symmetry, but is, for example, tilted relative to it, it is advantageous for the sensors to be at the same distance from the tilting axis.

[0017] Advantageously, the upper part is connected to the lower part by at least one connecting link. This at least one elastic element then has hinges, preferably film hinges, through which the connecting link is connected to the upper and lower parts. If the upper part moves relative to the lower part, the positions of the hinges change. In order to keep the connecting links connected to the upper and lower parts, the hinge must also move and assume a different angle. The hinge, particularly a film hinge, opposes this movement with an elastic force. The movement of the hinge therefore corresponds to the deformation of the elastic element. Depending on the design of the hinges, especially the film hinges, the force required to deform the elastic elements can vary in magnitude.

[0018] In a preferred embodiment, at least one connecting web is located on each side of the plane of symmetry and / or the pivot axis. Each hinge has two elements that are rotatable or pivotable relative to each other, referred to as tabs or lugs. One of these tabs of each hinge is connected to the connecting web, while the other of the two tabs is connected to the upper or lower part. If the hinge is designed as a film hinge, the two tabs are preferably formed integrally. In a particularly preferred embodiment, the upper part, the lower part, the connecting webs, and the hinges are formed integrally.

[0019] Preferably, the sensor device has at least two stops that limit the tilting of the upper part relative to the lower part in each direction. This prevents overstressing and overloading of the elastic elements. However, this means that torques causing the upper part to tilt relative to the lower part in the respective direction can only be measured or determined up to a maximum value.

[0020] Preferably, the stops are arranged on the lower part, and the upper part comes into contact with these stops as soon as it has been pivoted sufficiently far in the respective direction relative to the lower part. A contact element, for example in the form of a hardened plate, can be arranged on the upper part for this purpose. Of course, the reverse arrangement, i.e., the stop on the upper part and the contact element on the lower part, can also be used. In a particularly preferred embodiment, one of the at least two sensors is located in the contact element or in one of the stops.

[0021] Preferably, the sensor device has at least one additional stop that limits the displacement of the upper part relative to the lower part. The additional stop is preferably located between the two stops. Particularly preferably, the additional stop is located in the preferred direction. Most preferably, the additional stop is located in the plane of symmetry of the base body, preferably in the plane of symmetry of the sensor device. In principle, the displacement of the upper part relative to the lower part is also limited by the two stops, which also limit the tilting. If one of the stops is in contact with the respective contact element, further tilting in that direction is no longer possible. If both stops are in contact with their respective contact elements, further displacement of the upper part relative to the lower part is no longer possible.However, it is then impossible to distinguish whether, in addition to the large force, a potentially smaller torque is also acting on the upper part or the sensor device. This is achieved with an additional stop. The additional stop is preferably designed such that, even when the contact element of the additional stop is in contact with it, tilting of the upper part relative to the lower part is still possible.

[0022] Preferably, the additional stop has a rolling contour, allowing the upper part to roll on the lower part or vice versa. This facilitates further tilting, even if further displacement is already prevented by the additional stop. Naturally, the additional stop can also be located on the upper part or the lower part, with the respective contact element on the other component of the base body.

[0023] In a preferred embodiment, the sensor device has an additional sensor arranged in the plane of symmetry and configured to determine the distance between the upper and lower parts. This additional sensor is preferably located in the auxiliary stop or its contact element.

[0024] Advantageously, the at least two sensors and / or the additional sensor include at least one Hall sensor and / or at least one optical sensor. With the at least two sensors and / or the additional sensor, it is possible to measure the distance without contact.

[0025] In a preferred embodiment, a permanent magnet is arranged on either the upper or lower part of the base body. At least two Hall sensors are positioned on the other part such that they are located within the magnetic field of the permanent magnet. When a force is applied to the upper part of the base body, this results in a displacement and / or tilting of the upper part, which in turn causes the permanent magnet to move relative to the two Hall sensors. Preferably, the two sensors are arranged such that a simple displacement of the upper part relative to the lower part results in the same change in the distance between the permanent magnet and the two Hall sensors. The sensors then detect a change in the magnetic field, and this change is also the same for both Hall sensors.This allows detection that the movement is solely a displacement of the upper part relative to the lower part, i.e., a longitudinal movement. If the force acting on the upper and / or lower part also causes the upper part to tilt relative to the lower part, the distance between the permanent magnet and the two Hall sensors will not change uniformly, but differently for each sensor. This also results in different changes to the magnetic field detected by the two sensors. In this way, the tilt angle around a specific axis can be determined.

[0026] This design of at least two sensors has the advantage that it directly measures a tilting and / or displacement of the upper part relative to the lower part, independent of the structure of the base body. An elastic element is advantageous, but not necessary.A sensor device comprising at least two Hall sensors and a base body with an upper part and a lower part, wherein the Hall sensors are arranged on the upper part and a permanent magnet on the lower part, or the Hall sensors on the lower part and the permanent magnet on the upper part, and wherein the sensor device is characterized in that the upper part is displaceable relative to the lower part from a zero position along the preferred direction and is tiltable about a tilting axis perpendicular to the preferred direction, wherein the at least two Hall sensors are each configured to determine a distance between the upper part and the lower part, so that a displacement and / or tilting of the upper part relative to the lower part from the zero position can be determined, therefore constitutes an invention of its own.This invention can be combined with all other features described herein that do not relate to the at least one elastic element.

[0027] Preferably, the at least two Hall sensors are positioned symmetrically to the plane of symmetry of the base body, and preferably symmetrically to the plane of symmetry of the entire sensor assembly. In a particularly preferred embodiment, at least three, and more preferably at least four, Hall sensors are provided, which are not positioned along a single straight line. In this way, a tilt about any axis can be detected, resulting in varying degrees of change in the detected magnetic fields of the Hall sensors used.

[0028] Preferably, the at least two sensors and / or the additional sensor include at least one contact sensor, one pressure sensor, and / or one capacitive sensor. Such a sensor is preferably arranged and configured to detect whether there is a gap between the upper and lower parts or whether the upper and lower parts are in contact.

[0029] With the aid of the accompanying figures, some exemplary embodiments of the present invention are explained in more detail below. They show Figures 1 to 3 schematic representations of functionalities implemented in the present invention, Figures 4 to 7 schematic representations of a basic body under various force influences and Figures 8 to 10 The schematic side view, sectional view and sensor positioning of a basic body.

[0030] Figure 1Figure 1 schematically shows a function implemented in a sensor device according to an embodiment of the present invention. A top part 2 and a bottom part 4 of a base body are shown schematically. Between the two is an elastic element 6, which in the schematic representation is designed as a spring. If a force 8, represented by the arrow, is applied in the direction corresponding to the arrow, the elastic element 6 is compressed. Due to the design and direction of the force 8, the top part 2 is displaced relative to the bottom part 4 along the direction of the applied force 8. Figure 1 illustrates the situation in which only a displacement takes place between the upper part 2 and the lower part 4.

[0031] In this situation, two stops 10 are present, which limit the maximum possible displacement. This occurs when the upper part 2 abuts the stops 10. A sensor 12 is shown between the upper part 2 and the lower part 4, through which the distance between the upper part 2 and the lower part 2 can be measured.

[0032] Figure 2 illustrates a situation in which only a tilting of the upper part 2 relative to the lower part 4 is possible. Instead of the single elastic element 6, which is in Figure 1 arranged in the middle, are in Figure 2 Two elastic elements 6 are shown. In the middle is an additional stop 14 on which the upper part rests. This representation was chosen to allow only a tilting, but not a displacement of the upper part 2 relative to the lower part 4. The stops 10 are again present on both sides. Unlike in Figure 1, in which, due to a displacement of the upper part 2, this could only come into contact with both attacks 10 together, can be in Figure 2 The upper part 2 only comes into contact with one of the two stops 10. This is possible when a torque 16 acts, which is represented by the curved arrow. The arrow is only meant to indicate that a torque is acting. The direction of the arrow does not define the direction of the torque.

[0033] The in Figure 2 The arrangement shown has two sensors 12, each configured to determine the distance between upper part 2 and lower part 4 at its respective position. The angle of the upper part 2 relative to the lower part 4 can be determined from the different distances between the upper part 2 and lower part 4, as well as from the position of the sensors 12. From this, the acting torque can be determined from the known force profiles of the elastic elements 6. It can be seen in Figure 2already that an elastic element 6 can also come out of engagement with the upper part 2 if this occurs, for example, through a pivoting caused by a torque 16. In Figure 2 This is the case for the right-hand of the two elastic elements 6.

[0034] In Figure 3 is the combination of the two situations Figure 1 and Figure 2This corresponds functionally to a sensor device according to an embodiment of the present invention. In this case, three elastic elements 6 are positioned between the upper part 2 and the lower part 4. These are compressed to varying degrees when a force 8 and / or a torque 16 is applied. In the illustrated embodiment, the two lateral elastic elements 6 are not yet in contact with the upper part 2. However, this is not necessarily the case. Designs in which the lateral elastic elements 6 are always in contact with the upper part 2 can also be advantageous in certain situations.

[0035] The in Figure 3 The embodiment shown has the two stops 10, the two sensors 12 and the additional stop 14.

[0036] Figure 4Figure 1 shows an embodiment of a base body 18 for a sensor device according to an exemplary embodiment of the present invention. The base body has a pyramid adapter 20, which is part of the upper part 2. The lower part 4 has the additional stop 14. Between the upper part 2 and the additional stop 14 of the lower part 4 are Figure 4 two connecting bridges 22 are shown, whose in Figure 4 The outer end is connected to the upper part 2 via a film hinge 24. This is in Figure 4 The inner end of the connecting webs 22 is connected to the additional stop 14 of the lower part 4 via a further film hinge 26.

[0037] Figure 5 shows the design from Figure 4Under the influence of a force 8, it can be seen that the upper part 2 was displaced downwards relative to the lower part 4, so that the connecting webs 22 are no longer parallel to each other and no longer parallel to the lower part 4. To achieve this position, the film hinges 24, 26 were elastically deformed. In this case, they form the elastic elements 6. The displacement of the upper part 2 relative to the lower part 4, caused by the force 8, ended the moment the upper part 2 abutted the additional stop 14.

[0038] Figure 6 The situation shows Figure 5 , where the force 8 is different than in Figure 5 The force no longer acts centrally, i.e., along the axis of symmetry of the base body 18, but offset from it. This also creates a torque 16, which, however, is not shown graphically. The upper part 2 is affected by the force acting from the Figure 4The resting position shown has been both shifted and pivoted. The upper part rests against the additional stop 14 and the stop 10 located on the left. In this example as well, the film hinges 24, 26 have been deformed and form the elastic elements. Figure 7 The correspondingly reversed situation is shown, in which the force 8 is not as in Figure 6 not to the left of the axis of symmetry, but to the right of the axis of symmetry of the base body 18. This is particularly evident in the Figures 5 and 6 , that the upper contact surface of the additional stop 14 is bent and designed as a rolling surface, so that the upper part 2 can be tilted particularly easily even when it is already in contact with the additional stop 14.

[0039] Figure 8 shows a side view of a basic body 18, as already described in Figure 4 was depicted. Figure 9 In contrast, a cross-sectional view through the basic body 18 shows Figure 8Measuring channels 28 can be identified, beginning in the lower part 4. A central measuring channel 28 runs through the additional stop 14 and is open upwards towards the upper part 2. The two lateral measuring channels 28 also begin in the lower part 4 and extend through openings in the connecting web 22.

[0040] Figure 10 shows the enlarged view from Figure 9The measuring channels 28 and the openings 30 in the connecting web 22 are visible. A permanent magnet 32 ​​is located at the bottom of the central measuring channel 28, and its magnetic field extends particularly through the central measuring channel 28. Two Hall sensors 34 are arranged on the side of the upper part 2 facing the lower part 4. These measure the magnetic field of the permanent magnet 32 ​​very precisely and can thus detect changes in the distance between the upper part 2 and the lower part 4 very accurately. Additionally, due to their arrangement, they can determine if the change differs in magnitude at the two respective positions of the Hall sensors 34. From this, a tilt can be calculated. Additionally or alternatively, sensors can also be arranged in the lateral measuring channels 28. Reference numeral list

[0041] 2 Top part 4 Bottom part 6 Elastic element 8 Force 10 Stop 12 Sensor 14 Additional stop 16 Torque 18 Base body 20 Pyramid adapter 22 Connecting bridge 24 Film hinge 26 Film hinge 28 Measuring channel 30 Opening 32 Permanent magnet 34 Hall sensor

Claims

1. A sensor device to determine forces and toques in an orthopedic device, comprising - at least two sensors (12) and - a main body (18) with an upper part (2) and a lower part (4) and at least one elastic element (6) arranged between the upper part (2) and the lower part (4), wherein the upper part (2) can be tilted from a zero position relative to the lower part (4) about a tilt axis perpendicular to a preferred direction, wherein at least one elastic element (6) is deformed and the at least two sensors (12) are each configured to determine a distance between the upper part (2) and the lower part (4), characterized in that the upper part (2) can be displaced relative to the lower part (4) along the preferred direction and that the sensors (12) determine the distance such, that a displacement and tilt of the upper part (2) relative to the lower part (4) from the zero position can be determined.

2. The sensor device according to claim 1, characterized in that the at least one elastic element (6) opposes a tilt of the upper part (2) relative to the lower part (4) in a first tilt direction with a different resistance to a tilt in a second tilt direction.

3. The sensor device according to claim 1 or 2, characterized in that the upper part (2) can be displaced relative to the lower part (4) along a plane of symmetry of the main body (18), preferably a plane of symmetry of the sensor device.

4. The sensor device according to claim 3, characterized in that the tilt axis lies in the plane of symmetry.

5. The sensor device according to claim 3 or 4, characterized in that the two sensors (12) are on opposite sides of the plane of symmetry and are preferably at the same distance from said plane of symmetry.

6. The sensor device according to one of the preceding claims, characterized in that the upper part (2) is connected to the lower part (4) by at least one connecting bar (22) and the at least one elastic element (6) comprises hinges, especially film hinges (24,26), by means of which the connecting bar (22) is connected to the upper part (2) and the lower part (4).

7. The sensor device according to one of the preceding claims, characterized in that the sensor arrangement has at least two end stops (10) each of which limits a tilt of the upper part (2) relative to the lower part (4) in one direction.

8. The sensor device according to one of the preceding claims, characterized in that the sensor arrangement has at least one additional end stop (14) by means of which the displacement of the upper part (2) relative to the lower part (4) is limited.

9. The sensor device according to claim 8, characterized in that the additional end stop (14) has a rolling contour on which the upper part (2) can roll on the lower part (4).

10. The sensor device according to one of the claims 3 to 9, characterized in that the sensor device has an additional sensor that is arranged in the plane of symmetry and configured to determine the distance between the upper part (2) and the lower part (4).

11. The sensor device according to one of the preceding claims, characterized in that the at least two sensors (12) and / or the additional sensor include at least one Hall sensor (34) and / or at least one optical sensor.

12. The sensor device according to one of the preceding claims, characterized in that the at least two sensors (12) and / or the additional sensor include at least one contact sensor, a pressure sensor and / or at least one capacitive sensor.