Vehicle seat with time-path optimisation of weight capturing

Abstract

The proposed solution relates to a vehicle seat (1) comprising a seat sub-assembly (10), a backrest sub-assembly (11), a floor assembly (13) which supports at least the seat sub-assembly (10), an adjustment apparatus (12) for adjusting the seat sub-assembly (10) and / or the backrest sub-assembly (11) relative to the floor assembly (13) using a drive device (3), and a control system (14) which is coupled to the drive device (3) and is designed to carry out the following steps: performing a long measurement by: activating the drive device (3) in order to bring about a first adjustment of the seat sub-assembly (10) and / or the backrest sub-assembly (11) relative to the floor assembly (13) for a predefined first adjustment duration and / or for a predefined first adjustment path; capturing at least one value of a parameter of the adjustment apparatus (12) and / or of the drive device (3) during the first adjustment; and determining a weight acting on the vehicle seat (1) on the basis of the at least one value of the parameter captured during the first adjustment; and performing a short measurement by: activating the drive device (3) in order to bring about a second adjustment of the seat sub-assembly (10) and / or the backrest sub-assembly (11) relative to the floor assembly (13) for a predefined second adjustment duration and / or for a predefined second adjustment path, wherein the second adjustment duration is shorter than the first adjustment duration and / or the second adjustment path is shorter than the first adjustment path; capturing at least one value of the parameter of the adjustment apparatus (12) and / or of the drive device (3) during the second adjustment; and determining the weight acting on the vehicle seat (1) on the basis of the at least one value of the parameter detected during the second adjustment.

Description

[0001] Brose Fahrzeugteile SE & Co.

[0002] Limited partnership, Coburg

[0003] Max-Brose-Str. 1

[0004] 96450 Coburg

[0005] 2024 175 WO

[0006] Vehicle seat with time-distance optimization of weight measurement

[0007] Description

[0008] The proposed solution involves a vehicle seat, a process, a corresponding computer program product, and a non-volatile, computer-readable storage medium.

[0009] Several functions in modern vehicles rely on seat occupancy detection. If a vehicle seat is occupied, the vehicle's control units regularly check whether the corresponding seat belt is fastened. Furthermore, airbag deployment can be linked to seat occupancy. In some cases, these and other functions can be improved by not only detecting whether the vehicle seat is occupied in any way, but also by quantifying the weight acting on the seat. For example, an unfastened seat belt alarm can be omitted if the vehicle seat is occupied by an object (e.g., a bag) but not by a passenger. Airbag deployment can also be adjusted to the passenger's weight to achieve optimized restraint.

[0010] In practice, for example, so-called Biddle mats or piezoelectric elements can be embedded in a seat to detect seat occupancy and provide an approximate weight measurement. Page 2

[0011] to carry out. However, such components require installation space and make manufacturing complex, partly due to the additional wiring.

[0012] DE 10 2006 061 669 A1 describes a method for determining the occupancy weight of a vehicle seat, wherein a seat element of the vehicle seat is adjustable by means of a drive unit, comprising the following steps: providing at least one measurement signal representing a state of the drive unit; controlling the drive unit for at least a predetermined duration; during the control period, acquiring the measurement signal; determining a load torque from the measurement signal according to a motor model; and determining the occupancy weight of the seat element as a function of the load torque. An electric drive unit may be provided for adjusting the seat height. However, it has been shown that the accuracy of the measurement could be improved.

[0013] DE 10 2017 217 331 A1 describes a method for operating an electromechanical massage device of a seat, in particular of a motor vehicle, which includes a massage drive with an electric motor, in which the electric motor is energized, a torque of the electric motor is detected and a reference value is determined from this, and on the basis of the reference value an occupancy of at least one section of the seat is determined.

[0014] German patent DE 10335734 A1 relates to a method for seat occupancy detection in a motor vehicle with at least one actuator for seat adjustment. The electrical power supply to the actuator(s) for seat adjustment is recorded during their operation and evaluated as a measure of seat occupancy. However, the accuracy of this measurement also has potential for improvement.

[0015] German patent DE 10 2004 047 907 A1 describes how to control one or more electric motors in such a way that, starting from the occupant's current seating position, a vehicle seat is moved beyond a target position. Shortly after exceeding the target position, the direction is reversed, and the seat moves back to the target position. The degree of movement beyond the target position is chosen so that the vehicle occupant is moved beyond the target position for only fractions of a second. The movement in the opposite direction then occurs in a comparable timeframe. This provides sufficient upward or downward movement to reliably classify the vehicle occupant without the need for acceleration curves.

[0016] 2024 175 WO page 3

[0017] or of the object on the vehicle seat using the measurement signals of the electric motor(s).

[0018] EP 1 000327 B1 describes a device and a method for detecting the weight of an object and / or an occupant on a vehicle seat. The weight measurement is repeated at defined intervals during vehicle operation in order to detect changes in the weight force acting on the vehicle seat.

[0019] The known solutions only provide satisfactory measurement accuracy with a comparatively long measurement duration.

[0020] The task is to improve weight measurement in vehicle seats.

[0021] This problem is solved by an object having the features of claim 1.

[0022] A vehicle seat comprises a seat assembly, a backrest assembly, a base assembly supporting at least the seat assembly (e.g., the seat assembly and the backrest assembly), and an adjustment device for adjusting the seat assembly and / or the backrest assembly relative to the base assembly, with a drive device. The vehicle seat further comprises a control system coupled to the drive device (e.g., communicatively and / or electrically), configured to perform the following steps: Performing a long measurement by: activating the drive device to effect an initial adjustment of the seat assembly and / or the backrest assembly relative to the base assembly for a predetermined initial adjustment duration and / or for a predetermined initial adjustment range; acquiring a value of a parameter of the adjustment device and / or the drive device during the initial adjustment;and determining a weight acting on the vehicle seat based on the parameter value recorded during the first adjustment; and performing a brief measurement by: activating the drive device to effect a second adjustment of the seat assembly and / or the backrest assembly relative to the floor assembly for a predetermined second adjustment duration and / or for a predetermined second adjustment range, wherein the second adjustment duration is shorter than the first adjustment duration and / or the second adjustment range is shorter than the first adjustment range; recording a value of the parameter of the adjustment device and / or the drive device during the second adjustment; and determining the force acting on the;

[0023] 2024 175 WO page 4

[0024] Vehicle seat weight acting on the vehicle seat based on the parameter value recorded during the second adjustment.

[0025] This method achieves high accuracy through the longer measurement, while only a short measurement is required for each subsequent measurement. Since weight typically does not change during vehicle use, except when, for example, a seat is vacated, a greater degree of inaccuracy can be tolerated for the second measurement. In some modern vehicles, seat occupancy and / or weight information is queried regularly, sometimes even every second, so the shorter duration of the second measurement(s) can have a particularly significant impact. The shorter measurement reduces wear on the adjustment mechanism and the drive system. It also reduces power consumption. Furthermore, the measurement is faster. Thus, the described method improves weight measurement in vehicle seats.

[0026] The control system can be configured to establish a relationship between the long and short measurements, and, during the short measurement, to determine the weight acting on the vehicle seat based on at least one parameter value and the relationship recorded during the second adjustment. This enables a particularly robust short measurement.

[0027] Furthermore, the control system can be configured to establish the relationship between the long measurement and the short measurement by determining at least one parameter value for a portion of the long measurement corresponding to the length of the short measurement. This allows a precise basis for the short measurement, or multiple short measurements, to be created from a single long measurement.

[0028] In one embodiment, the control system is configured to determine the relationship between the long measurement and the short measurement as the ratio between at least one value of the parameter for the long measurement, or a value derived therefrom, and at least one value of the parameter for the part of the long measurement corresponding to the length of the short measurement, or a value derived therefrom. This enables a particularly robust yet simple evaluation.

[0029] It may also be provided that the control system is configured to define the relationship between the long measurement and the short measurement as the ratio between at least one value of the parameter of the long measurement, or one of them.

[0030] 2024 175 WO page 5

[0031] to determine the derived value and at least one value of the parameter from a short measurement (e.g., the aforementioned short measurement or another short measurement), or a value derived from it. This allows for a particularly precise comparison.

[0032] The parameter can be an electrical parameter, in particular a current, voltage, or power. Alternatively or additionally, the parameter can specify a torque. Alternatively or additionally, the parameter can specify a rotational speed (e.g., of the drive device), in particular the maximum speed reached during adjustment. These parameters allow for easy conversion to a weight, e.g., using a conversion formula and / or a lookup table (LUT). The parameter can relate to one or more drive motors of the drive device. Optionally, the control system is configured (e.g., for each of two directions) to measure the voltage and / or current of the drive device starting from a base value (e.g.,The parameter (zero) is increased until a component of the height adjustment device, in particular a drive motor of the drive unit, is set in motion from a standstill. The value of the parameter is then, for example, the current or voltage reached. The control system can also be configured to stop the drive unit as soon as it registers the movement. This allows weight measurement to be achieved with only minimal movement. The adjustment in the first and second directions is therefore minimal and hardly noticeable or imperceptible to a seat user. Alternatively (or additionally), the parameter (or another parameter) can specify an adjustment path traveled within a certain (in particular, predetermined) time, in particular the length of this adjustment path, or an adjustment time required for a certain (in particular, predetermined) adjustment path.These parameters also allow for easy conversion into a weight, e.g. using a conversion rule and / or a LUT.

[0033] In one embodiment, at least one value of the respective parameter is the current integral of the current supplied to a drive motor of the drive device over the respective adjustment duration and / or over the respective adjustment range. This enables a particularly precise measurement.

[0034] The long measurement can encompass the first number of revolutions of a motor shaft in the drive device, and the short measurement can encompass a smaller, second number of revolutions of the motor shaft. This allows for a simple comparison of the parameter values.

[0035] 2024 175 WO page 6

[0036] Specifically, it can be stipulated that the first number is a multiple of the second number. This allows for a particularly simple yet robust calculation of the weight based on the second measurement.

[0037] Alternatively or additionally, it may be provided that the first adjustment path is a multiple of the second adjustment path and / or that the first adjustment time is a multiple of the second adjustment time.

[0038] In one embodiment, the first adjustment path comprises a distance in a first direction and the same distance in an opposite, second direction. The second adjustment path can alternatively or additionally comprise only the distance in the first direction or only the distance in the second direction. This enables high accuracy of the second measurement.

[0039] It may be planned that after a long measurement, several short measurements are carried out at intervals, particularly periodically. This allows for high accuracy to be achieved through the long measurement, while the short measurements permit regular confirmation of the measured value, even with a high repetition frequency.

[0040] The control system can be configured to check whether a predetermined condition is met and, in response to this, to perform another long measurement after one or more short measurements. The predetermined condition might be, for example, a deviation of the weight determined in a short measurement from a reference value that exceeds a threshold, such as a deviation from the reference value of more than + / - 10%. The reference value could be, for example, the weight determined in the (or one of the) preceding long measurement, or the weight determined in the first short measurement within or after the last long measurement. This allows the system to determine whether the weight determined in the short measurements is still plausible. If not, a new long measurement can be performed to precisely re-measure the weight.

[0041] The control system can be configured to perform the short measurement at a time after the long measurement.

[0042] 2024 175 WO page 7

[0043] The adjustment device can be a height adjustment device for adjusting the distance between the seat assembly and the base assembly. This allows for particularly precise weight measurements.

[0044] The control system can be configured to determine the weight acting on the seat assembly based on the measured values ​​of the parameter from the adjustment in both directions. This is based on the idea that a height adjustment motor generates a torque during adjustment, which corresponds to a current. This current can be measured by the control system (which may include electronics located on the vehicle seat and / or a central vehicle control unit) and used to evaluate the load. Furthermore, this is based on the understanding that friction and tolerances can affect the accuracy of the weight measurement, but that measuring in both adjustment directions allows such influences to be compensated for. Thus, a particularly precise weight determination can be achieved with a very simple setup.The control system can be configured to activate the drive device for a predetermined time and / or over a predetermined adjustment range (e.g. measured by the number of motor rotations) in the first direction and in the second direction.

[0045] The control system can include a storage medium containing, for example, a model that assigns a corresponding value of an applied weight to each parameter value, specifically to each possible parameter value. Using this model (e.g., in the form of a learning load table), the weight can be determined in a particularly simple manner. The model can also be a machine learning model that has been trained, for example, with various weight loads. Optionally, the model assigns a value of an applied weight to each parameter value (specifically, each possible parameter value) for several possible settings of the height adjustment device. This takes into account that, due to the kinematics of the height adjustment device, the same torque is not required for adjustment in every setting.

[0046] Optionally, the model assigns a value for an acting weight to each parameter value (specifically, each possible value of the parameter) with respect to an adjustment in the first direction on the one hand, and with respect to an adjustment in the second direction on the other (independently of each other). This further improves the accuracy of the measurement. For example, the control system is configured to determine the acting weight separately based on the detected parameter value for each direction.

[0047] 2024 175 WO page 8

[0048] The first direction is determined, and the second direction is determined based on the recorded parameter value. Optionally, the control system is also configured to calculate the weight acting on the seat assembly from the two weight values ​​obtained in this way, for example, by calculating an average. In particular, a weighted average can be calculated, for which each of the two individual values ​​is multiplied by a weighting factor.

[0049] The control system can be configured to record the parameter values ​​for calibration purposes when no weight is acting on the vehicle seat. This can be done as described above, i.e., by activating the drive device to adjust the distance between the seat assembly and the base assembly in the first direction and recording the value of the drive device parameter during this adjustment; and, optionally, by activating the drive device to adjust the distance between the seat assembly and the base assembly in the second direction and recording the value of the drive device parameter during this adjustment. Since the weight acting on the seat assembly is known (0 kg), the recorded values ​​can be stored as a reference and / or used for calibration, e.g., of the model. Calibration can correct aging-related effects, e.g.,Changes in efficiency, friction, etc., over the lifespan of the vehicle seat are taken into account. Optionally, the control system can be configured to automatically repeat the calibration at predefined intervals. This ensures consistently high accuracy in weight determination.

[0050] The drive device can include a brushless DC motor. Such motors allow for particularly precise adjustment of the adjustment speed by adjusting the rotational speed. Generally, the adjustment speed can be determined by the rotational speed.

[0051] The control system is optionally configured to receive seat occupancy data from a camera or other detection device (such as radar). This data can include camera images or other information that the control system analyzes, for example, to determine the height of a passenger and / or their position in the seat. This data can be used in conjunction with the calculated weight. Furthermore, the calculated weight can be corrected based on the seat occupancy data; for example, the passenger's position in the seat can be used to correct an underestimated weight.

[0052] 2024 175 WO page 9

[0053] The control system can include a memory in which a model is stored that establishes at least one relationship between the weight acting on the seat assembly and the input values ​​of adjuster position and the value of the measured parameter. This enables fast and reliable evaluation.

[0054] It can be advantageous if the control system is configured so that the acquisition of at least one parameter value in the first direction and / or in the second direction occurs within one complete revolution of a gear stage of the height adjustment device and / or the drive unit. This allows for the compensation of irregularities due to gear modulation, resulting in a more accurate measurement.

[0055] The features described above can also be used to further develop the method and / or system described and / or claimed herein.

[0056] According to one aspect, a method is provided for determining a weight acting on a vehicle seat, in particular on a vehicle seat according to any embodiment described herein. The vehicle seat comprises a seat assembly, a backrest assembly, a base assembly supporting at least the seat assembly, and an adjustment device (e.g., a height adjustment device) for adjusting (e.g., a distance) the seat assembly and / or the backrest assembly relative to the base assembly by means of a drive device. The method comprises the following steps: Performing a long measurement by: Activating the drive device to effect an initial adjustment of the seat assembly and / or the backrest assembly relative to the base assembly for a predetermined initial adjustment duration and / or for a predetermined initial adjustment range;Capturing at least one value of a parameter of the adjustment device and / or the drive unit during the first adjustment; and determining a weight acting on the vehicle seat based on the at least one value of the parameter captured during the first adjustment; and performing a short measurement by: activating the drive unit to effect a second adjustment of the seat assembly and / or the backrest assembly relative to the floor assembly for a predetermined second adjustment duration and / or for a predetermined second adjustment range, wherein the second adjustment duration is shorter than the first adjustment duration and / or the second adjustment range is shorter than the first adjustment range; capturing at least one value of the parameter of the;

[0057] 2024 175 WO page 10

[0058] Adjustment device and / or drive unit during the second adjustment; and determining the weight acting on the vehicle seat based on at least one parameter value recorded during the second adjustment. Regarding the advantages, please refer to the above information on the vehicle seat.

[0059] The procedure can include steps from the various configurations of the control system described above.

[0060] According to one aspect, a computer program product is specified, comprising instructions which, when executed by one or more processor(s) (e.g., of the control system described above), cause them to execute the procedure described above.

[0061] According to one aspect, a non-volatile, computer-readable storage medium is specified on which instructions are stored which, when executed by one or more processor(s) (e.g., of the control system described above), cause them to execute the procedure described above.

[0062] The underlying concept of the invention will be explained in more detail below with reference to the exemplary embodiments shown in the figures. The figures show:

[0063] Fig. 1 shows a schematic view of a vehicle seat with a height adjustment device which is supported by a base assembly, the base assembly being exemplified as a longitudinal adjustment device;

[0064] Fig. 2 shows a view of a seat assembly of a vehicle seat;

[0065] Fig. 3 shows a top view of the arrangement according to Fig. 2;

[0066] Fig. 4 shows a partially enlarged view of the arrangement according to Fig. 2, depicting a drive device on a swivel element for connecting the seat assembly to a floor assembly in the form of a longitudinal adjustment device;

[0067] Fig. 5 shows an alternatively designed drive device for the vehicle seat according to Fig. 1;

[0068] 2024 175 WO page 11

[0069] Fig. 6 shows a method for determining a weight acting on the vehicle seat according to Fig. 1; and

[0070] Fig. 7 shows the current of a drive motor against the position of a component adjusted by it.

[0071] Fig. 1 shows a vehicle seat 1, which can be arranged, for example, as a front seat or as a rear seat in the second or third row of a vehicle. The vehicle seat 1 has a seat assembly 10, to which a backrest assembly 11 is attached in a tilt-adjustable manner and which is connected via a height adjustment device 12 to a base assembly 13 in the form of a longitudinal adjustment device for longitudinally adjusting the vehicle seat 1 along a longitudinal direction X.

[0072] The longitudinal adjustment device 13 typically has, as can be seen in Fig. 1 in conjunction with Figs. 2 and 3, two pairs of guide rails 130A, 131A, 130B, 131B, each arranged on one side of the seat assembly 10 and spaced apart from each other along a transverse direction Y perpendicular to the longitudinal direction X. The lower guide rails 131A, 131B are fixedly connected to a vehicle floor 2 and can be fixedly connected to it in a pre-assembly state. The upper guide rails 130A, 130B, on the other hand, are coupled to pivot elements 120A, 121A, 120B, 121B of the height adjustment device 12. The floor assembly 13 is connected to the seat assembly 10 via the height adjustment device 12.

[0073] The pivot elements 120A, 121A, 120B, 121B together with the upper guide rails 130A, 130B and side frame parts 100A, 100B of the seat assembly 10 form two pairs of four-bar linkages. The pivot elements 120A, 121A, 120B, 121B are each pivotally connected at one end to the respective upper guide rail 130A, 130B and at the other end to the seat assembly 10, e.g., to a cross tube 102 extending pivotably between the frame parts 100A, 100B of the seat assembly 10 (or to another part of the seat assembly 10) such that by pivoting the pivot elements 120A, 121A, 120B, 121B, the height of the seat assembly 10 can be changed along a height direction Z (perpendicular to the longitudinal direction X and transverse direction Y). This changes the distance between the seat assembly 10 and the floor assembly 13.The height adjustment device 12 is thus designed to adjust a distance between the seat assembly 10 and the floor assembly 13. To effect a.

[0074] 2024 175 WO page 12

[0075] The adjustment includes the height adjustment device 12 (at least) a drive device 3 (with one or more drive motors).

[0076] The floor assembly, in this case the longitudinal adjustment device 13, supports the seat assembly 10. The seat assembly 10 supports the backrest assembly 11.

[0077] The height adjustment device 12 is an adjustment device for adjusting the seat assembly 10 (and, because the backrest assembly 11 is mounted on the seat assembly 10 in the example shown, also the backrest assembly 11) relative to the floor assembly, i.e. here to the longitudinal adjustment device 13, with the drive device 3.

[0078] The vehicle seat 1 further comprises a control system 14 operationally coupled to the drive device 3, which is configured to perform the following steps:

[0079] Performing a long measurement by:

[0080] o Activating the drive device 3 to effect a first adjustment of the seat assembly 10 and / or the backrest assembly 11 relative to the floor assembly 13 for a predetermined first adjustment duration and / or for a predetermined first adjustment path;

[0081] o Recording at least one value of a parameter of the adjusting device 12 and / or the drive device 3 during the first adjustment; and

[0082] o Determining a weight acting on vehicle seat 1 based on at least one value of the parameter recorded during the first adjustment; and

[0083] Perform a short measurement by:

[0084] o Activating the drive device 3 to effect a second adjustment of the seat assembly 10 and / or the backrest assembly 11 relative to the floor assembly 13 for a predetermined second adjustment duration and / or for a predetermined second adjustment path, wherein the second adjustment duration is shorter than the first adjustment duration and / or the second adjustment path is shorter than the first adjustment path;

[0085] 2024 175 WO page 13

[0086] o Capturing at least one value of the parameter of the adjusting device 12 and / or the drive device 3 during the second adjustment; and

[0087] o Determining the weight acting on vehicle seat 1 based on at least one value of the parameter recorded during the second adjustment.

[0088] The control system 14 is configured to establish a relationship between the long measurement and the short measurement. The control system 14 is also configured to determine the weight acting on the vehicle seat 1 during the short measurement, based on at least one value of the parameter and that relationship recorded during the second adjustment. The relationship between the long measurement and the short measurement is specified, for example, by a factor. If the value of the parameter (which is, for example, a current integral) is measured from the short measurement, it can be calculated by the factor, for example, by multiplying it, to obtain a value corresponding to the long measurement. Alternatively, for example, the value of the long measurement can be calculated from the value of the short measurement (each in the form of an average current) using a known profile (see Fig. 7), which is, for example,resulting from differences in kinematics.

[0089] In the present example, the control system 14 is designed to determine the relationship between the long and short measurements by calculating a parameter value for a portion of the long measurement whose length corresponds to the length of the short measurement. An exemplary embodiment is explained below in connection with Fig. 7. Furthermore, it is conceivable to perform a plausibility check of the value of the short and / or the long measurement. For example, it is checked whether the value of the short measurement lies within a predefined interval. For comparable quantities, such as average currents, a maximum deviation of + / - 20% around a predefined value can be tolerated. In this way, errors during the short measurement can be detected.

[0090] Furthermore, it is exemplified that the control system 14 determines the relationship between the long measurement and the short measurement in the form of a ratio between the value of the parameter of the long measurement (or a value calculated therefrom) M and the value of the parameter for the part of the long measurement corresponding to the length of the short measurement (or a value calculated therefrom) N, i.e., for example, as M / N or as N / M.

[0091] 2024 175 WO page 14

[0092] Instead of using a portion of the long measurement as a reference, the control system 14 can also determine the relationship between the long measurement and the short measurement as the ratio between the value of the parameter of the long measurement (or a value derived from it) and the value of the parameter of another short measurement (or a value derived from it). For this purpose, a long measurement and a short reference measurement can first be performed, followed by the actual short measurement(s).

[0093] As shown in Fig. 1, an adjustment in a first direction R1 increases the distance between the seat assembly 10 and the base assembly 13, while an adjustment in the opposite, second direction R2 decreases the distance between the seat assembly 10 and the base assembly 13. Only a minimal adjustment range is required for weight determination, e.g., a few mm in relation to the distance between the seat assembly 10 and the base assembly 13.

[0094] The drive unit 3 can be activated at different adjustment speeds and has a minimum and a maximum adjustment speed. The control system 14 is configured to activate the drive unit 3 at the minimum adjustment speed, e.g., first in the first direction R1 and then in the second direction R2, or alternatively at an adjustment speed lower than the maximum adjustment speed (or an adjustment speed for a regular setting). This ensures that the weight measurement is barely or not at all perceptible to a seat user.

[0095] The parameter in question is an electrical parameter, e.g., the current of at least one drive motor 31 of the drive device 3, e.g., the total current drawn by it or the current of one phase of the drive motor 31. Alternatively or additionally, the applied power can also be used as a parameter. The current corresponds to a respective torque (of the drive motor(s)) of the drive device 3. Depending on the magnitude of the acting weight, for example, from a passenger, a greater or lesser torque must be applied by the drive device 3 for an adjustment, e.g., by a predetermined adjustment range. Therefore, a predetermined relationship between the current (generally the parameter) and the acting weight (possibly the torque of the passenger) can be established.The weight is determined based on the current adjustment position of the height adjustment device 12) by the control system 14. By performing the measurement in both adjustment directions R1 and R2, inaccuracies that have different effects in the different directions can be factored out.

[0096] 2024 175 WO page 15

[0097] For example, by calculating an (optionally weighted) average of weight values ​​determined separately for the two directions R1 and R2. Inaccuracies due to friction, tolerances, wear, and the like can be factored out using measurements taken with the vehicle seat 1 unoccupied. For instance, the difference between the current (generally: parameter values) measured in a downward direction with the seat unoccupied and a downward direction with the seat occupied is calculated and then multiplied by a first factor to determine the weight in the downward direction measurement. Similarly, the difference between the current (generally: parameter values) measured in an upward direction with the seat occupied and a measurement taken with the seat unoccupied is calculated and then multiplied by a second factor to determine the weight in the upward direction measurement. The first and second factors can be different or the same.The weight is then determined, for example, by the sum of the two weight values.

[0098] The current (generally: the parameter value) for a given direction can be determined as the average value over a given adjustment range. Alternatively, the integral of the current over the adjustment duration can be used as the parameter. Optionally, the start-up phase of the drive motor can be excluded.

[0099] The parameter can also specify, for example, a maximum speed reached during adjustment, an adjustment path traveled within a certain time, or an adjustment time required for a specific adjustment path.

[0100] The predefined relationship between the parameter value and the weight is stored, for example, in a storage medium 140 of the control system 14. This relationship can be a model that assigns a value of an acting weight to each possible value of the current integral, the current intensity, or another parameter. Because these relationships depend on the adjustment direction in the example shown, the model also assigns a value of an acting weight to each possible value of the current intensity with respect to an adjustment in the first direction R1 and with respect to an adjustment in the second direction R2, independently of each other. And because these relationships also depend on the adjustment position in the example shown, the model assigns a value of an acting weight to each possible value of the current integral, the current intensity, or other parameter for all possible setting positions of the height adjustment device 12.The model can include a LUT and / or a trained machine learning model.

[0101] 2024 175 WO page 16

[0102] To create the LUT and / or the training data for the machine learning model, test masses (e.g., 0 kg, 10 kg, 20 kg, 40 kg, and 80 kg, optionally with finer subdivisions) with various known weights can be placed on the seat assembly 10, and the parameter values ​​(especially at multiple adjustment positions) can be determined as described above. This allows for the creation of a table of factors that assigns a weight value to each parameter value (e.g., current) at each adjustment position. This table can be stored on the memory medium. Interpolation can be performed between any two entries in the table.

[0103] To compensate for changes in efficiency and due to friction, etc., the control system 14 is designed to perform calibration runs (e.g., regularly). For this purpose, the control system 14 is configured to record the parameter values ​​for calibration when no weight is acting on the vehicle seat 1.

[0104] A camera 4 (or another detection device such as radar) is aimed at vehicle seat 1 to capture the size, position, or other characteristics of a passenger seated in vehicle seat 1 in camera images. Camera 4 is directly or indirectly connected to the control system 14, so that the control system 14 receives data from camera 4 regarding the occupancy of vehicle seat 1. This data can be in the form of captured images or as pre-processed information on weight, position, or other characteristics. By combining the determined weight with information on size and position, seat occupancy can be determined with particular precision. Furthermore, an inaccurate weight reading, for example, due to an offset seating position, can be corrected in this way. For this purpose, a correction table can be stored in the memory medium, which assigns correction factors to different seating positions (e.g., further forward, further back).Since occupant cameras are increasingly installed in modern vehicles, such a measure is particularly easy to implement. The control system 14 is designed to receive the seat occupancy data based on the camera images, e.g., via a dedicated interface 141.

[0105] The exemplary design of the height adjustment device 12 is explained in more detail below with reference to Fig. 2-4.

[0106] The frame parts 100A and 100B of the seat assembly 10 are connected to each other at one rear end via the cross tube 102. The cross tube 102 is (in this example) pivotable.

[0107] 2024 175 WO page 17

[0108] mounted on the frame parts 100A, 100B and carries the associated rear pivot elements 121 A, 121 B.

[0109] In a front area, a seat pan 101 is arranged on the frame parts 100A, 100B to form a seat surface of the seat assembly 10.

[0110] In the illustrated embodiment, the drive device 3 of the height adjustment device 12 is arranged, for example, on the rear pivot element 121A on the side of the guide rail pair 130A, 131A, as can be seen in Figures 2 and 3 in conjunction with Figure 4. The drive device 3 is designed as a spindle drive and serves to introduce an adjusting force into the pivot element 121A, so that by pivoting the pivot element 121A, the pivot elements 120A, 121A, 120B, 121B can be pivoted as a whole, thereby adjusting the height of the seat assembly 10, i.e., changing the distance between the seat assembly 10 and the base assembly 13.

[0111] At a set seat height, the seat assembly 10 is held in position on the swivel element 121A by the drive device 3. The drive device 3 is designed to be sufficiently robust to absorb and dissipate forces acting on the seat assembly 10.

[0112] Referring now to Figs. 2 to 4, the drive device 3 has a spindle 30 which is pivotably connected at one end to the associated guide rail 130A via a bearing element.

[0113] The swivel element 121A is coupled to an attachment connected to the guide rail 130A and is pivotably mounted on the guide rail 130A (here via a bearing bolt).

[0114] The spindle 30 extends substantially perpendicularly from the end connected to the guide rail 130A, with a threaded shaft 300 on which an external thread is formed. An adjustment mechanism 32 is operatively connected to the spindle 30 such that, by driving the adjustment mechanism 32, it can be adjusted longitudinally along a longitudinal direction L relative to the spindle 30. This allows the length of an end of the spindle 30, which is pivotably mounted between the adjustment mechanism 32 and the end pivotably mounted on the guide rail 130A, to be changed, thereby transmitting an adjustment force to the pivoting element 121A.

[0115] 2024 175 WO page 18

[0116] to initiate and thus adjust the distance between the seat assembly 10 and the floor assembly 13.

[0117] The adjusting gear 32 has a spindle nut and a drive element in the form of a drive worm, which engages with an external toothing of the spindle nut via a worm gear. The drive element is driven by a drive motor 31, so that the spindle nut can be set into rotation by the drive motor 31 and via a motor shaft 310 of the drive motor 31. The spindle nut engages with the external thread of the spindle 30 via an internal thread such that, by rotating the spindle nut, it rolls along the spindle 30 and is thereby adjusted longitudinally along the longitudinal direction L relative to the spindle 30.

[0118] Optionally, the height adjustment device 12 includes a further drive motor 31, which can be arranged, for example, in a mirror image to the drive motor 31 on the rear pivoting element 121B on the side of the guide rail pair 130B, 131B. This is illustrated schematically in Fig. 3. Based on the values ​​of the parameters of both drive motors (e.g., the sum), the acting weight can be determined with particular accuracy.

[0119] The drive motors 31 are brushless direct current motors (BLDC motors) whose speed and torque can be adjusted with particular precision.

[0120] The adjustment gear 32 is pivotally mounted on the pivoting element 121A. During an adjustment movement in which the length of the section of the spindle 30 extending between the adjustment gear 32 and the rail-side end is changed, the adjustment gear 32 can pivot on the pivoting element 121A. In this way, a change in the position of the pivoting element 121A relative to the base assembly 13 can be compensated for.

[0121] The drive motor 31 is pivotably mounted on the swivel element 121A via the adjustment gear 32. When the swivel element 121A is moved, the drive motor 31 and the adjustment gear 32 move together with the swivel element 121A.

[0122] Fig. 5 shows an example of an alternatively designed drive device for the vehicle seat according to Fig. 1, which has a drive motor 31 mounted on the seat assembly 10, which drives a pinion 33 via a gearbox. The pinion 33 meshes with a curved

[0123] 2024 175 WO page 19

[0124] Tooth segment 34, which is attached to the upper guide rail 130A. Otherwise, its operation is as described above.

[0125] Fig. 6 shows a method for determining a weight acting on the vehicle seat 1, the method comprising the following steps:

[0126] Step S10: Perform a long measurement by following these steps:

[0127] Step S100: Operating the drive device 3 to effect a first adjustment of the seat assembly 10 and / or the backrest assembly 11 (here the seat assembly 10 and the backrest assembly 11) relative to the floor assembly 13 for a predetermined first adjustment duration and / or for a predetermined first adjustment path.

[0128] Step S101: Reading in at least one value of a parameter of the adjustment device 12 and / or the drive device 3 (here, for example, the current integral of the drive motor 31) during the first adjustment.

[0129] Step S102: Determining a weight acting on vehicle seat 1 based on at least one value of the parameter recorded during the first adjustment.

[0130] Step S11: Perform a short measurement by following these steps:

[0131] Step S110: Activating the drive device 3 to effect a second adjustment of the seat assembly 10 and / or the backrest assembly 11 (here, the seat assembly 10 and the backrest assembly 11) relative to the floor assembly 13 for a predetermined second adjustment duration and / or for a predetermined second adjustment path. It may be provided that the second adjustment duration is shorter than the first adjustment duration and / or the second adjustment path is shorter than the first adjustment path.

[0132] Step S111: Recording at least one value of the parameter of the adjustment device 12 and / or the drive device 3 (here again, by way of example, the current integral of the drive motor 31) during the second adjustment.

[0133] Step S112: Determining the weight acting on vehicle seat 1 based on at least one parameter value recorded during the second adjustment.

[0134] 2024 175 WO page 20

[0135] Regarding specific implementations of the procedure, reference is made to the above and following information on control system 14 to avoid repetition. The procedure may include corresponding procedural steps that correspond to the functionality of control system 14 described herein.

[0136] The storage medium 140 contains a computer program product comprising instructions which, when executed by one or more computers, in particular when executed by the control system 14 (e.g. by its processor 142), cause it to carry out the procedure described above.

[0137] The single setpoint input can be the first setpoint. The control system might, for example, input a second setpoint along with the first. Alternatively, the control system 14 can first input the first setpoint and then input the second setpoint at a later time.

[0138] Since measuring a large weight at a lower rotational speed can be more accurate than at a higher rotational speed (and conversely, measuring a small weight at a higher rotational speed can be more accurate), the control system 14 can be configured to set an adjustment speed based on an input value, e.g., based on a previously determined weight acting on the vehicle seat 1. Alternatively, e.g., if such a measurement is not (yet) available, another measuring device can be used, e.g., as already described, the camera 4 or the like. With an initial estimate of the weight, an adjustment speed optimal for that weight can be used. For example, the storage medium 140 stores a corresponding adjustment speed for each possible weight value or a functional relationship that outputs a corresponding adjustment speed for an input weight.

[0139] Other conditions can also influence the optimal adjustment speed, such as temperature. Therefore, the ambient temperature, for example, can be used by a component of the height adjustment device 12 or the drive unit 3 as a preselection parameter for the adjustment speed. At low temperatures, the adjustment current increases significantly. At low temperatures (e.g., below a predefined threshold), the rotational speed can be reduced, resulting in a lower phase voltage. A temperature measurement, provided to the control system 14, for example, by a temperature sensor 35 to measure the temperature of the drive unit 3 (see Fig. 1), is then used, for example, to read in a corresponding adjustment speed (e.g., via a tabular or functional relationship between the two).

[0140] 2024 175 WO page 21

[0141] Therefore, it can generally be provided that the control system 14 sets the variable adjustment speed based on an input value.

[0142] Optionally, the starting current (i.e., at different speeds during a speed ramp) can be excluded from the measurement. Alternatively, this starting current can be included in the measurement.

[0143] Fig. 7 illustrates an exemplary current profile of the drive device 3. Specifically, Fig. 7 shows the current amplitude of the phase current of the drive motor 31 of the drive unit 3 against the adjustment path. The position is represented on the x-axis as the number of motor revolutions. One complete revolution of the motor shaft corresponds to one motor revolution.

[0144] The diagram in Fig. 7 shows that within a single motor revolution, the current fluctuates between a maximum and a minimum, resulting in a wavy current profile over several revolutions. If the mean (or integral) current is calculated for each motor revolution (or other moving window), these fluctuations per revolution can be factored out. These mean values ​​are illustrated by a dashed line. However, it is also evident that the mean values ​​exhibit a variable pattern. A repeating pattern is discernible, extending over a fixed number of motor revolutions and then repeating. This pattern is illustrated by vertical lines and labeled as the first measurement range A. This pattern results, for example, from...from the design of the drive device 3 and / or the adjustment unit, in particular from the design of the adjustment gear 32.

[0145] As can be seen in Fig. 7, the individual sections, each containing a complete pattern, also differ from one another. For example, the pattern in the center of the diagram has a higher overall average current than the pattern to its left and a lower average than the pattern to its right. Furthermore, the maximum deviation of the current within a pattern—that is, the difference between the lowest and highest current values ​​within a pattern—can vary between the individual sections. This difference is illustrated for the central pattern in Fig. 7 by a double vertical arrow.

[0146] 2024 175 WO page 22

[0147] The applied weight can be determined from the displayed measurements, for example, by calculating the weight from the average current of a sample using a predetermined conversion rule (e.g., a LUT). For instance, the conversion rule assigns a weight value to a current value in each position of the height adjustment device 12. The accuracy of the measurement can be determined from the maximum deviation.

[0148] For example, the value of the respective parameter is the current integral of the current supplied to the drive motor 31 (for one phase or in total over all phases) of the drive device 3 over the respective adjustment duration and / or over the respective adjustment path.

[0149] For the long measurement, the parameter can be measured, for example, over the first measuring range A. For the short measurement, the parameter is determined, for example, over a portion of the first measuring range A, such as the second measuring range B illustrated in Fig. 7. The second measuring range B is smaller than the first measuring range A. In this case, the second measuring range B is a portion of the first measuring range A. In the example shown, the second measuring range B comprises the last n motor revolutions (n=3 in this example) of the m motor revolutions of the first measuring range A (m=39 in this example). The long measurement comprises a first number of revolutions of the motor shaft 310 of the drive device 3, and the short measurement comprises a comparatively smaller second number of revolutions of the motor shaft 310. In this case, the first number is a multiple of the second number. Different ratios are conceivable.A multiple of 13 is shown, but this can also be chosen higher, e.g., up to 50, or lower, e.g., 2 or between 2 and 13. Consequently, the first adjustment range is a multiple of the second adjustment range, and the first adjustment time is a multiple of the second adjustment time. However, it is not strictly necessary to use integer multiples of the motor revolutions for this. The second measuring range can correspond to a multiple of a gearbox or motor modulation period.

[0150] Specifically, a long measurement is performed over the first measuring range A. The weight is then calculated from the determined current integral. A second current integral for the second measuring range B is also recorded. Later, a short measurement is performed, which has the same length as the second measuring range B. The (third) current integral of this second measurement is determined. Based on any deviation from the second current integral, it can be determined whether the weight has changed or not.

[0151] 2024 175 WO page 23

[0152] No. Furthermore, the weight can be calculated by comparison. If a large deviation is found, a new, longer measurement can be initiated.

[0153] The length of the long measurement and / or the short measurement can also be varied, e.g. depending on the measured temperature of the drive, the electronics or the ambient temperature (e.g., a shorter measurement is taken at a higher temperature than at a lower temperature).

[0154] As mentioned above, a measurement can also have a portion in the first direction R1 and a (e.g., equally long) portion in the second direction R2. For example, the first adjustment path of the long measurement might include a distance in the first direction R1 and an equally long distance in the opposite, second direction R2. The second adjustment path of the short measurement might include, for example, only the distance in the first direction R1 or only the distance in the second direction R2.

[0155] After the long measurement has been performed and the relationship to the short measurement established, several short measurements can be carried out, e.g., at intervals, particularly at regular intervals. Furthermore, the first measurement can be repeated cyclically, e.g., after a predetermined time or a predetermined number of short measurements.

[0156] The length of the first measurement can be adjusted to achieve a predetermined accuracy. The longer the measurement is performed, the more accurate the calculated weight becomes (until maximum accuracy is reached).

[0157] The control system 14 comprises the computer-readable storage medium 140 in which a model is stored with which at least one relationship is established between the weight acting on the vehicle seat 1, in particular on the seat assembly 10, and the adjuster position and / or the value of the measured parameter (e.g. the current of the drive motor, e.g. of one of several phases or the currents of all phases).

[0158] 2024 175 WO Page 24 Reference List

[0159] 1 vehicle seat

[0160] 10 Seat component assembly

[0161] 100A, 100B frame part

[0162] 101 Seat tub

[0163] 102 Cross tube

[0164] 11 Backrest assembly

[0165] 12 Height adjustment device

[0166] 120A, 120B Swivel element

[0167] 121A, 121B Swivel element

[0168] 13 Floor assembly (longitudinal adjustment device) 130A, 130B Guide rail

[0169] 131A, 131B Guide rail

[0170] 14 Control system

[0171] 140 storage medium

[0172] 141 Interface

[0173] 142 processor

[0174] 2 Vehicle floor

[0175] 3 Drive device

[0176] 30 spindle

[0177] 300 threaded shaft

[0178] 31 Drive motor

[0179] 310 Motor shaft

[0180] 32 adjustable gearboxes

[0181] 33 sprockets

[0182] 34 tooth segment

[0183] 35 Temperature sensor

[0184] 4 cameras

[0185] L Longitudinal direction

[0186] R1, R2 direction

[0187] A first measuring range

[0188] B second measuring range

[0189] X Longitudinal direction

[0190] Y transverse direction

[0191] Z Altitude direction

[0192] 2024 175 WO

Claims

Page 25 Claims 1. Vehicle seat (1) comprising a seat assembly (10), a backrest assembly (11), a base assembly (13) supporting at least the seat assembly (10) and an adjustment device (12) for adjusting the seat assembly (10) and / or the backrest assembly (11) relative to the base assembly (13) with a drive device (3), characterized by a control system (14) coupled to the drive device (3) and configured to perform the following steps: Performing a long measurement by: o Activating the drive device (3) to effect a first adjustment of the seat assembly (10) and / or the backrest assembly (11) relative to the floor assembly (13) for a predetermined first adjustment duration and / or for a predetermined first adjustment path; o Recording at least one value of a parameter of the adjustment device (12) and / or the drive device (3) during the first adjustment; and o Determining a weight acting on the vehicle seat (1) based on the at least one value of the parameter recorded during the first adjustment; and Perform a short measurement by: o Activating the drive device (3) to effect a second adjustment of the seat assembly (10) and / or the backrest assembly (11) relative to the floor assembly (13) for a predetermined second adjustment duration and / or for a predetermined second adjustment path, wherein the second adjustment duration is shorter than the first adjustment duration and / or the second adjustment path is shorter than the first adjustment path; o Recording at least one value of the parameter of the adjustment device (12) and / or the drive device (3) during the second adjustment; and o Determining the weight acting on the vehicle seat (1) based on the at least one value of the parameter recorded during the second adjustment.

2. Vehicle seat (1) according to claim 1, characterized in that the control system (14) is configured to establish a relationship between the long measurement and the short measurement and to determine the short measurement 2024 175 WO page 26 of the weight acting on the vehicle seat (1) based on at least one value of the parameter and the relationship recorded during the second adjustment.

3. Vehicle seat (1) according to claim 2, characterized in that the control system (14) is configured to establish the relationship between the long measurement and the short measurement by determining at least one value of the parameter for a part of the long measurement corresponding to the length of the short measurement.

4. Vehicle seat (1) according to claim 3, characterized in that the control system (14) is configured to determine the relationship between the long measurement and the short measurement as the ratio between the at least one value of the parameter of the long measurement, or a value derived therefrom, and the at least one value of the parameter for the part of the long measurement corresponding to the length of the short measurement, or a value derived therefrom.

5. Vehicle seat (1) according to claim 2, characterized in that the control system (14) is configured to determine the relationship between the long measurement and the short measurement as the ratio between the at least one value of the parameter of the long measurement, or a value derived therefrom, and the at least one value of the parameter of a short measurement, or a value derived therefrom.

6. Vehicle seat (1) according to claim 4 or 5, characterized in that at least one value of the respective parameter is the current integral of the current supplied to a drive motor (31) of the drive device (3) over the respective adjustment duration and / or over the respective adjustment path.

7. Vehicle seat (1) according to one of the preceding claims, characterized in that the long measurement comprises a first number of revolutions of a motor shaft (310) of the drive device (3) and the short measurement comprises a smaller, second number of revolutions of the motor shaft (310).

8. Vehicle seat (1) according to claim 7, characterized in that the first number is a multiple of the second number. 2024 175 WO page 27 9. Vehicle seat (1) according to one of the preceding claims, characterized in that the first adjustment path is a multiple of the second adjustment path and / or the first adjustment time is a multiple of the second adjustment time.

10. Vehicle seat (1) according to one of the preceding claims, characterized in that the first adjustment path comprises a distance in a first direction (R1) and the same distance in an opposite, second direction (R2), while the second adjustment path comprises only the distance in the first direction (R1) or the distance in the second direction (R2).

11. Vehicle seat (1) according to one of the preceding claims, characterized in that after a long measurement several short measurements are carried out at time intervals from each other.

12. Vehicle seat (1) according to claim 11, characterized in that the control system (14) is configured to check whether a predetermined condition is met and, in response to the fact that the predetermined condition is met, to perform a long measurement again after several short measurements, wherein the predetermined condition is, for example, a deviation of the weight determined in a short measurement from a reference value that exceeds a threshold value.

13. Vehicle seat (1) according to one of the preceding claims, characterized in that the control system (14) is configured to perform the short measurement at a time after the long measurement.

14. Vehicle seat (1) according to one of the preceding claims, characterized in that the adjusting device (12) is a height adjustment device for adjusting a distance between the seat part assembly (10) and the floor assembly (13).

15. Vehicle seat (1) according to one of the preceding claims, characterized in that the control system (14) has a storage medium (140) in which a model is stored which assigns to each possible value of the parameter a value of an acting weight, wherein the model assigns to each possible value of the parameter to several possible setting positions of the adjustment device (12) a value of an acting weight. 2024 175 WO page 28 16. Vehicle seat (1) according to one of the preceding claims, characterized in that the control system (14) is configured to record the values ​​of the parameter for calibration when no weight acts on the vehicle seat (1).

17. Method for determining a weight acting on a vehicle seat (1), the vehicle seat (1) comprising a seat assembly (10), a backrest assembly (11), a base assembly (13) supporting at least the seat assembly (10) and an adjustment device (12) for adjusting the seat assembly (10) and / or the backrest assembly (11) relative to the base assembly (13) with a drive device (3), in particular according to one of the preceding claims, the method comprising the following steps: Performing (S10) a long measurement by: o Activating (S100) the drive device (3) to effect a first adjustment of the seat assembly (10) and / or the backrest assembly (11) relative to the floor assembly (13) for a predetermined first adjustment duration and / or for a predetermined first adjustment path; o To detect (S101) at least one value of a parameter of the adjustment device (12) and / or the drive device (3) during the first adjustment; and o To determine (S102) a weight acting on the vehicle seat (1) based on the at least one value of the parameter detected during the first adjustment; and Perform (S11) a short measurement by: o Activating (S110) the drive device (3) to effect a second adjustment of the seat assembly (10) and / or the backrest assembly (11) relative to the floor assembly (13) for a predetermined second adjustment duration and / or for a predetermined second adjustment path, wherein the second adjustment duration is shorter than the first adjustment duration and / or the second adjustment path is shorter than the first adjustment path; o To detect (S111) at least one value of the parameter of the adjustment device (12) and / or the drive device (3) during the second adjustment; and o To determine (S112) the weight acting on the vehicle seat (1) based on the at least one value of the parameter detected during the second adjustment. 2024 175 WO page 29 18. Computer program product comprising instructions which, when executed by one or more processor(s) (142), cause the processor(s) to execute the method according to claim 17.

19. Non-volatile computer-readable storage medium (140) on which instructions are stored which, when executed by one or more processor(s) (142), cause them to execute the method according to claim 17. 2024 175 WO

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