DEVICE AND METHOD FOR ADAPTING THE CONTOUR OF A BACK ELEMENT TO THE POSTURE OF A PERSON

Abstract

A device and a method for adapting a contour of a back element to a posture of a person. The device includes a seat element and aback element connected to the seat element in a tiltable way, for accommodating a person, and a control unit. A bearing pressure sensor is configured for measuring an actual bearing pressure distribution exerted by the person. The back element includes a first actuating element for changing the contour of the back element. The control unit selects a predetermined posture and a characteristic target posture parameter matching the predetermined posture, calculates an actual posture parameter from the actual bearing pressure distribution and compares the actual posture parameter with the target posture parameter, and when the actual posture parameter and the target posture parameter match, actuates the first actuating element to adapt the contour of the back element to the posture of the person.

Claims

1-18. (canceled)

19. A device comprising: a seat element and a back element connected to the seat element in a tiltable way, for accommodating a sitting or lying person and for adapting a contour of the back element to a posture of the person, and a control unit, wherein the seat element includes at least one bearing pressure sensor connected to the control unit for measuring an actual bearing pressure distribution exerted by the person, wherein the back element includes at least one first actuating element connected to the control unit for changing the contour of the back element, and wherein the control unit is programmed: to select a predetermined posture and at least one characteristic target posture parameter matching the predetermined posture, to calculate an actual posture parameter from the actual bearing pressure distribution measured by the bearing pressure sensor and to compare the actual posture parameter with the target posture parameter, and if the actual posture parameter matches the target posture parameter, to actuate the first actuating element in such a way as to adapt the contour of the back element to the posture of the person.

20. The device according to claim 19, wherein the at least one target posture parameter is a pelvic rotation angle about the transverse, sagittal and/or longitudinal axis.

21. The device according to claim 19, wherein the control unit is further programmed to issue instructions for the person to adopt the predetermined posture.

22. The device according to claim 19, further comprising a seat angle sensor connected to the control unit, wherein the seat angle sensor is configured for measuring the seat angle between the seat element and the back element and wherein the control unit is further programmed to select the predetermined posture depending on the seat angle.

23. The device according to claim 19, wherein the seat element includes a second actuating element connected to the control unit for changing the contour of the seat element.

24. The device according to claim 19, wherein the at least one bearing pressure sensor is a surface sensor, with at least one bearing pressure sensor being arranged in the area of the seating surface of the seat element.

25. The device according to claim 24, wherein the control unit is programmed to run an iterative algorithm that maps a Mandelbrot set in order to limit the measuring range for the actual bearing pressure distribution on the bearing pressure sensor.

26. The device according to claim 23, wherein the first and/or second actuating element has one or several air chambers with associated valves, the air chambers being connected to at least one pump and the control unit being programmed to open and close the valves.

27. The device according to claim 26, wherein the control unit is programmed to fill or, respectively, vacuum-seal the air chambers independently of each other by actuating the valves and the pump.

28. The device according to claim 26, wherein the air chambers comprise a loose, particulate filling material, which is freely displaceable in the filled state of the air chambers and is fixed in its position in the vacuum-sealed state of the air chambers.

29. A method of adapting a contour of a back element to the posture of a person, wherein a person is accommodated in a posture on a seat element connected to the back element, especially in a tiltable way, comprising the following steps: a) selecting a predetermined posture and at least one characteristic target posture parameter allocated to the predetermined posture, b) measuring the actual bearing pressure distribution, c) determining an actual posture parameter from the actual bearing pressure distribution, d) comparing the actual posture parameter with the selected target posture parameter, e) repeating steps b)-d) until a match of the actual posture parameter with the target posture parameter is determined, and f) if the actual posture parameter matches the target posture parameter: adapting the contour of the back element to the posture of the person.

30. The method according to claim 29, wherein the seat angle between the seat element and the back element is determined prior to step a), and that the predetermined posture and the characteristic target posture parameter are selected in step a) depending on the seat angle.

31. The method according to claim 29, wherein, between steps a) and b), instructions are issued for the person to adopt the predetermined posture and/or to correct the posture of the person.

32. The method according to claim 29, wherein, in step e), one or several air chamber(s) that are independent of each other and can be shut off by one or several valve(s) are pre-filled with a selected air pressure by opening the valve(s) and are subsequently fixed by closing the valve(s) in order to adapt the contour of the back element, with the selected air pressure corresponding to a degree of hardness of the air chambers.

33. The method according to claim 29, wherein the contour of the back element is changed and/or modulated at predetermined time intervals after the contour of the back element has been adapted to the posture of the person.

34. The method according to claim 29, wherein the method is performed using a device comprising: a seat element and a back element connected to the seat element in a tiltable way, for accommodating a sitting or lying person and for adapting a contour of the back element to a posture of the person, and a control unit, wherein the seat element includes at least one bearing pressure sensor connected to the control unit for measuring an actual bearing pressure distribution exerted by the person, wherein the back element includes at least one first actuating element connected to the control unit for changing the contour of the back element, wherein the control unit is programmed: to select a predetermined posture and at least one characteristic target posture parameter matching the predetermined posture, to calculate an actual posture parameter from the actual bearing pressure distribution measured by the bearing pressure sensor and to compare the actual posture parameter with the target posture parameter, and if the actual posture parameter matches the target posture parameter, to actuate the first actuating element in such a way as to adapt the contour of the back element to the posture of the person.

35. A piece of seating furniture with a seating surface and a backrest, comprising a device according to claim 19, with the seat element being integrated into the seating surface and the back element being integrated into the backrest.

36. A seat cover for being placed on a piece of seating furniture, comprising a device according to claim 19.

Description

SHORT DESCRIPTION OF THE FIGURES

[0078] Preferred embodiment variants of the invention are illustrated in further detail below with reference to the figures. Therein:

[0079] FIG. 1 shows a schematic view of a device for adapting the contour of the back element according to a first embodiment variant of the invention with a person in an upright sitting posture,

[0080] FIG. 2 shows a schematic view of a device for adapting the contour of the back element and the seat element according to a second embodiment variant of the invention with a person in an upright sitting posture,

[0081] FIG. 3 shows a schematic view of a device for adapting the contour of the back element and the seat element according to a third embodiment variant of the invention with a person in an upright sitting posture,

[0082] FIG. 4 shows a schematic view of the device of FIG. 1 with a person in an inclined sitting posture,

[0083] FIG. 5 shows a schematic view of the device of FIG. 1 with a person in a reclining posture,

[0084] FIG. 6a shows a first actual bearing pressure distribution of a person in an upright sitting posture,

[0085] FIG. 6b shows a second actual bearing pressure distribution of a person in an upright sitting posture,

[0086] FIG. 6c shows a third actual bearing pressure distribution of a person in a backwards inclined sitting posture,

[0087] FIG. 6d shows a fourth actual bearing pressure distribution of a person in a backwards inclined sitting posture,

[0088] FIG. 6e shows a fifth actual bearing pressure distribution of a person in a reclining posture, and

[0089] FIG. 6f shows a sixth actual bearing pressure distribution of a person in a reclining posture.

WAYS OF IMPLEMENTING THE INVENTION

[0090] FIG. 1 shows a schematic view of the device 100 according to the invention, on which a person 1 is positioned in an upright sitting posture. In this case, the device 100 comprises a back element 2 and a seat element 3, which are interconnected in a tiltable way and include a seat angle 4. The person 1 thereby places a load on the seat element 3 with their pelvis or, respectively, the two ischial tuberosities 21.

[0091] According to a further embodiment variant, which has not been depicted in further detail in the figures, the back element 2 can also be connected rigidly to the seat element 3 rather than being tiltable relative to it.

[0092] In the rear area of the seat element 3, a bearing pressure sensor 5 is provided which measures the actual bearing pressure distribution exerted by the person 1 on the seat element 3. The bearing pressure sensor 5 is preferably designed as a surface sensor or, respectively, as a surface pressure sensor, wherein the surface sensor can simultaneously measure the bearing pressure at different points and can thus determine the bearing pressure distribution directly in the plane of the seat element 3. In an alternative embodiment variant, the bearing pressure sensor 5 can also be distributed over the entire seat element 3, although this has not been depicted any further in the figures.

[0093] In addition, the back element 2, as shown in the embodiment variant of FIG. 1, comprises a second bearing pressure sensor 5a, which is arranged in the lower area of the back element 2 and essentially connects directly to the first bearing pressure sensor 5. The device 100 can thus enable complete detection of the bearing pressure distribution even in case of high seat angles 4, e.g., in an inclined sitting posture 20a or a reclining posture 20b, as illustrated in FIGS. 4 and 5.

[0094] In an alternative embodiment variant, which is not depicted either in the figures, the bearing pressure sensor can extend across the entire seat element 3 and across the entire back element 2.

[0095] In the back element 2, at least one first actuating element 6 is provided, which is designed for changing the contour 7 of the back element 2. In this case, the actuating element 6 is preferably arranged in the area 8 of the lumbar spine and in the transition zone to the thoracic spine of the person 1 so that the actuating element 6 constitutes a support, in particular in the form of a lumbar support, after the adaptation to the posture of the person 1 has occurred.

[0096] According to a first embodiment variant of the invention, the first actuating element 6 comprises two air chambers 9 which are connected to a pump 11 via fluid lines 10. In addition, in all fluid lines 10, one valve 12 is provided in each case, which can selectively separate or establish the connection between the respective air chamber 9 and the pump 11. When the valves 12 are closed, the air chambers 9 are closed and the trapped air cannot escape from the air chambers 9. By appropriately opening and closing the valves 12, the individual air chambers 9 can be filled with different pressures, whereby an arbitrarily adjustable actuating element 6 is obtained.

[0097] According to the invention, the air chambers 9 are filled with air. In alternative embodiment variants, the air chambers 9 can also be filled with other fluids, such as, for example, various gases or liquids. In this case, the air chambers 9 are designed for receiving any fluids.

[0098] In FIG. 2, a device 101 according to a second embodiment variant is shown. In this case, the first actuating element 6a has three air chambers 9a, which partially overlap each other. Again, as already described previously for FIG. 1, the air chambers 9a are connected, in this case, to a pump 11, in each case via fluid lines 10, with valves 12 always being provided in the fluid lines 10 between the pump 11 and the air chambers 9a.

[0099] In the seat element 3, the device 101 in FIG. 2 additionally comprises a second actuating element 6b, which is designed for changing the contour 7a of the seat element 3. The second actuating element 6b also has an air chamber 9b, which is connected to a pump 11a by means of a fluid line 10 via a valve 12. In this case, the pumps 11, 11a are designed for simultaneously filling and vacuum-sealing the air chambers 9a, 9b.

[0100] As indicated in FIG. 2, the air chambers 9a, 9b in the device 101 are filled with a loose, particulate filling material 13. In this case, the filling material 13 is freely displaceable when the air chambers 9a, 9b are filled with air, whereby the air chambers 9a, 9b can adapt particularly easily to the posture of the person 1. If the air chambers 9a, 9b are now vacuum-sealed, the air chambers 9a, 9b permanently retain their shape, which has been imprinted by the individual back or spine profile or, respectively, by the thigh, and can thus reliably adapt the contour 7 of the back element 2 and/or the contour 7a of the seat element 3 to the posture of the person 1.

[0101] Moreover, the features described above and below with reference to FIG. 1 apply mutatis mutandis to the device 101 according to the second embodiment variant, unless otherwise described.

[0102] In FIG. 3, a device 102 according to a third embodiment variant is shown. In this embodiment variant, the actuating element 6c only has a single air chamber 9c, with the actuating element 6c and the air chamber 9c being arranged essentially over the entire back element 2. In this case, the air chamber 9c is filled with a particulate filling material 13, as already described previously for the air chamber 9a in FIG. 2. By vacuuming-sealing the air chamber 9c by means of the pump 11, the filling material 13 can be fixed in its position and the contour 7 of the back element 2 can thus be adapted to the posture of the person.

[0103] With regard to the further features of FIG. 3, reference is made to the above description of FIGS. 1 and 2.

[0104] In an alternative embodiment variant, which, however, has not been depicted in any further detail in the figures, all air chambers 9, 9a, 9b, 9c are connected, in each case, to a separate pump 11, 11a via a valve 12. In this way, all air chambers 9, 9a, 9b, 9c can be filled simultaneously with different pressures or can be vacuumed-sealed independently of each other, which allows the actuating elements 6, 6a, 6b, 6c to be adjusted in a complex and versatile manner.

[0105] The device 100, 101, 102 according to the first, second and third embodiment variants in FIGS. 1 to 3 furthermore comprises a seat angle sensor 14 for measuring the seat angle 4 between the seat element 3 and the back element 2.

[0106] The device 100, 101, 102 comprises a control unit 50, which is connected to the pumps 11, 11a, the valves 12, the seat angle sensor 14 and the bearing pressure sensor 5, 5a via control lines 15. In an alternative embodiment variant, instead of the control lines 15, wireless connections can also exist between the control unit 50 and the pumps 11, 11a, the valves 12, the seat angle sensor 14 and the bearing pressure sensor 5, 5a.

[0107] According to a further embodiment variant, the device 100, 101, 102 can also comprise an inclination sensor connected to the control unit 50, which measures the inclination of the seat element 3 to the horizontal, which, however, has not been depicted in any further detail in the figures.

[0108] The control unit 50 is programmed to perform a method 200 of adapting the contour 7 of the back element 2 to the posture of the person 1. In one embodiment variant, the control unit 50 is thus programmed as follows: [0109] to select a predetermined posture and a characteristic target posture parameter matching the predetermined posture, in particular depending on the seat angle 4, [0110] to preferably issue instructions for adopting the selected predetermined posture, [0111] to determine an actual posture parameter from the actual bearing pressure distribution measured by the bearing pressure sensor 5 and to compare the determined actual posture parameter with the target posture parameter, [0112] if the actual posture parameter and the target posture parameter match, to actuate the actuating elements 6, 6a, 6c in such a way as to adapt the contour 7 of the back element 2 to the posture of the person 1.

[0113] In a further embodiment variant, the control unit 50 is furthermore programmed to run an iterative algorithm that maps the Mandelbrot set in order to limit the measuring range on the bearing pressure sensor 5, 5a (surface sensor) for measuring the actual bearing pressure distribution. By mapping the Mandelbrot set onto the measuring surface of the bearing pressure sensor 5, 5a, the measuring range can be reliably restricted to the measuring range which is relevant for determining the actual bearing pressure distribution. In this connection, reference is made to the statements in the introductory part of the above description.

[0114] The preferred embodiments of the device 100, 101, 102 are subsequently illustrated based on the method 200 according to the invention and FIGS. 1 to 5. In this case, the method 200 according to the invention can preferably be performed using a device 100, 101, 102. The control unit 50 of the device 100, 101, 102 is thus always programmed to perform the method 200 accordingly.

[0115] In the preferred embodiment variant, the method 200 according to the invention of adapting the contour 7 of the back element 2 to the posture of a person 1 thus comprises the following steps (in a specific order): [0116] a1) measuring the seat angle 4 between the seat element 3 and the back element 2; a) selecting a predetermined posture and at least one characteristic target posture parameter allocated to the predetermined posture, in particular depending on the seat angle 4; [0117] b1) issuing instructions for the person to adopt the predetermined posture; [0118] b) measuring the actual bearing pressure distribution; [0119] c) determining the actual posture parameter from the actual bearing pressure distribution; [0120] d) comparing the determined actual posture parameter with the selected target posture parameter, [0121] e) repeating steps b1)-d) until a match of the actual posture parameter with the target posture parameter is determined, [0122] f) if the actual posture parameter matches the target posture parameter: adapting the contour 7 of the back element 2 to the posture of the person 1.

[0123] In this case, steps a1) and b1) are optional and can optionally be omitted independently of each other, according to further embodiment variants.

[0124] The seat angle 4 is measured in step a1) using the seat angle sensor 14, and, in step b), the actual bearing pressure distribution is measured using the bearing pressure sensor 5.

[0125] The output of instructions to the person 1 in step b1) preferably occurs via a display 70 of a computer or a smartphone 60, which is preferably connected wirelessly to the control unit 50. The instructions can thereby be indicated aurally and/or visually so that the person 1 can easily correct any incorrect postures and can adopt the predetermined posture correctly.

[0126] As shown in FIGS. 1, 2 and 3, the person 1 adopts an essentially upright posture 20, which corresponds to a physiologically correct sitting posture. In this posture 20, only the ischial tuberosities 21 rest on the seat element 3; in this case, there is no contact of the coccyx 22 or sacrum 23 with the seat element 2, or, respectively, no significant pressure transfer to the bearing pressure sensor 5, 5a through the coccyx and sacrum 22, 23 can be detected.

[0127] In FIG. 4, the device 100 is again shown, with the person 1 adopting a backwards inclined sitting posture 20a. Therein, both the ischial tuberosities 21 and the coccyx and sacrum 22, 23 are in contact with the seat element 2.

[0128] Finally, the device 100 is shown in FIG. 5, with the person 1 adopting a reclining posture 20b. In this case, both the ischial tuberosities 21 and the coccyx 22 no longer have any contact with the seat element 2. The body section weight of the person 1 in the area of the pelvis is now supported exclusively by the sacrum 23.

[0129] In all postures 20, 20a, 20b, the pelvis of the person 1 is always aligned physiologically correctly, whereby the lumbar spine forms a lordosis in the area 8. In order to avoid pelvic rotations that are not adjusted to the seating system, the contour 7 of the back element 2 is adapted to the respective posture 20, 20a, 20b so that the actuating element 6, 6a, 6c can serve as a permanent support, can counteract fatigue of the posture-stabilizing muscles and can thus prevent damage associated with poor posture.

[0130] As shown in FIGS. 1 to 5, the postures 20, 20a, 20b match, in each case, the predetermined postures selected by the method 200. If there is a deviation from the respective predetermined posture, e.g., if the pelvis is rotated and the lumbar spine forms either a hyperlordosis or a kyphosis, an instruction to correct the posture can then be issued via the control unit 50 and via the smartphone 60 connected to the control unit 50 or via a computer or the like. If the posture 20, 20a, 20b is adopted correctly, the control unit 50 can additionally issue instructions to maintain the correct posture 20, 20a, 20b, while the actuating elements 6 are adapted to the person's posture.

[0131] In a preferred embodiment variant of the method 200, for adapting the contour 7 of the back element 2, the valves 12 to the air chambers 9 are opened in step f), and the air chambers 9 are pre-filled with a selected air pressure. This pre-filling can also take place with the valves 12 open throughout the entire method 200 until the posture has been adopted correctly and the valves 12 are finally closed for fixing the air chambers. The air pressure during pre-filling can be preset or adjusted according to a desired degree of hardness. For example, the degree of hardness can be adjusted by the person 1 during the method 200 via the smartphone 60 in connection with the control unit 50.

[0132] In FIGS. 6a to 6f, actual bearing pressure distributions 30, 31, 32, 33, 34, 35 are shown, which each are measured by the bearing pressure sensor 5 and each correlate with different postures 20, 20a, 20b of the person 1 on the device 100, 101, 102.

[0133] In this case, the bearing pressure distribution 30 in FIG. 6a corresponds to an upright posture 20, as it is illustrated in FIGS. 1-3. A pelvic rotation angle about the transverse axis of approximately 0 can thereby be determined as the actual posture parameter. The bearing pressure distribution 30 is thus characterized by two peak sitting pressures 36a, 36b which are at a distance from the pelvic centre line 38 and correspond to the bearing pressures exerted by the ischial tuberosities 21. Bearing pressure from the coccyx or sacrum 22, 23 is not detected in this case.

[0134] In FIG. 6b, however, a bearing pressure distribution 31 of the same upright posture 20 as in FIG. 6a is shown, but with a pelvic rotation to be corrected. In addition to the peak sitting pressures 36c, 36d exerted by the ischial tuberosities 21, a peak sitting pressure 37a can also be identified from the actual bearing pressure distribution 31 which is exerted by the coccyx or sacrum 22, 23 and indicates the rotation of the pelvis deviating from the predetermined upright posture. The pelvic rotation angle derivable from the bearing pressure distribution 31 is therefore not 0, as specified by the target posture parameter, but approximately 25. In the course of the method 200, instructions can now be issued for the person 1 to correctly adopt the predetermined posture or, respectively, to reduce the pelvic rotation angle , or the actuating elements can be actuated appropriately for correction.

[0135] The bearing pressure distribution 32, as shown in FIG. 6c, corresponds to a backwards inclined sitting posture 20a, as it is illustrated in FIG. 4. In this case, the pelvic rotation angle is approximately 32. The bearing pressure distribution 32 shows peak sitting pressures 36e, 36f which are exerted by the ischial tuberosities 21, like previously the bearing pressure distribution 30 and 31. Moreover, a peak sitting pressure 37b exerted by the coccyx or sacrum 22, 23 is visible.

[0136] In FIG. 6d, a bearing pressure distribution 33 corresponding to a backwards inclined sitting posture with a pelvic rotation angle of approximately 45 is in turn shown. The peak sitting pressures 36g, 36h emanating from the ischial tuberosities 21 are reduced in intensity compared to the bearing pressure distributions 31, 32 in FIGS. 6b and 6c and are shifted forward towards a higher pelvic rotation angle . The peak sitting pressure 37c exerted by the coccyx or sacrum 22, 23, however, is located around the 45 point on the pelvic centre line 38.

[0137] In FIG. 6e, a bearing pressure distribution 34 is shown which corresponds to a flatly reclining posture 20b, as it is illustrated in FIG. 5. What is noticeable first of all is that the bearing pressure distribution 34 does not show any peak sitting pressures that are exerted by the ischial tuberosities 21. By contrast, a dominant peak sitting pressure 37d exerted by the person's sacrum 23 is visible. In this case, the pelvic rotation angle is approximately 90. Furthermore, it can be seen in FIG. 6e that, in addition to a pelvic rotation angle about the transverse axis of the pelvis, a pelvic rotation angle about the sagittal axis of the body can also be identified. The pelvic rotation angle thereby manifests itself as a deviation of the peak sitting pressure 37d from the pelvic centre line 38.

[0138] Finally, in FIG. 6f, a bearing pressure distribution 35 is shown which corresponds to a flatly reclining posture of a person 1, with the lordotic curvature of the lumbar spine being eliminated progressively. This leads to further rotation of the pelvis, which ultimately manifests itself in a pelvic rotation angle of over 90. In the specific case, a peak bearing pressure 37e which is exerted by the sacrum 23 and is located approximately at the position of the pelvic rotation angle of 101 can be seen in the bearing pressure distribution 35. In addition, a pelvic rotation angle can again be identified as a deviation of the peak bearing pressure 37e from the pelvic centre line 38. With a larger pelvic rotation angle , the pelvis is increasingly stressed.

[0139] The purely kinematic consideration of the pelvic and spinal structures (2 ischial tuberosities, coccyx and sacrum) as a functional unit during the transmission of contact force allows a generalized coordinate to be selected within a configuration space defined via the Mandelbrot set or, respectively, the geometric relationships derived therefrom in order to describe their change of position in all three body levels. In this case, the pelvic centre line 38 defines the pelvic rotation angle in the bearing pressure distributions 30-35 of FIGS. 6a-6f as a generalized coordinate along a straight line on the bearing pressure sensor 5 or 5a. When a peak sitting pressure 37b exerted by the coccyx and sacrum 22, 23 is measured for the first time, as shown in FIG. 6c, the position of the 11.25 point of the pelvic rotation angle can be found as half the distance between the peak sitting pressure 37b and a connecting line of the peak sitting pressures 36e and 36f. The individual position of the 11.25 point in relation to the peak sitting pressures of the ischial tuberosities, which remains geometrically constant over a pelvic rotation angle range , thereby emerges apparently as an anatomical law, wherein deviations and, respectively, correction factors, for example depending on gender, age, weight, etc., can be taken into account. Thus, by determining the position of the 11.25 point and calculating the distance of the peak sitting pressures 36e and 36f at the point in time of detecting the peak sitting pressure 37b, the entire scaling of the pelvic rotation angle along the pelvic centre line 38 can be calculated, with the 0 point being shifted by 11.25 towards a smaller pelvic rotation angle . The length from 0 to 11.25 is thereby defined via the relationship 0.250.5C, with the radius of the base circle C of the Mandelbrot set being calculated via twice the distance between the ischial tuberosities 21 (represented by the peak sitting pressures 36c, 36d) and representing a pelvic rotation angle of 90 in total. As soon as the scaling is performed based on 3 peak pressure ranges, hence, depending on the pelvic rotation angle , either all 3 ranges can be combined in a reliable manner (sitting postures that are inclined backwards), or 2 ranges (upright sitting positions) or only 1 range (lying positions) can be used for evaluating the actual bearing pressure distribution, especially since, for example, the degree of hardness and/or the installation position of a sensor can significantly influence the pressure transmission and detection, respectively.

[0140] According to an embodiment variant of the invention, the method 200 can include a further step of calibrating the actual posture parameter. If, in this case, the actual posture parameter is, for example, a pelvic rotation angle , the calibration can be performed as described in the previous paragraph by identifying a backwards inclined posture 20a for the first time, measuring the peak sitting pressure 37a from the coccyx and sacrum for the first time, and inferring the 11.25 point therefrom.

[0141] According to a further embodiment variant of the device 100, 101, 102, the controller 50 can also be designed for performing the above-described steps.

[0142] Furthermore, in FIG. 1, a piece of seating furniture 300 with a seating surface 303 and a backrest 302 is shown, the piece of seating furniture 300 comprising the device 100. In this case, the seat element 3 is integrated into the seating surface 303 of the piece of seating furniture 300, and the back element 2 is integrated into the backrest 302.

[0143] According to FIG. 3, the device 102 is shown as a seat cover 400 which can be placed on a piece of seating furniture 500 without any structural changes.