WO2024083824A1

WO2024083824A1 - Method for determining a height of a movable device

Info

Publication number: WO2024083824A1
Application number: PCT/EP2023/078832
Authority: WO
Inventors: Thomas Block; Mathias Winberg; Kaustubh Gandhi; Sara Soltani
Original assignee: Robert Bosch Gmbh
Priority date: 2022-10-18
Filing date: 2023-10-17
Publication date: 2024-04-25
Also published as: DE102022211030A1

Abstract

The invention relates to a method for determining a height of a movable device, comprising the steps of providing the movable, in particular portable, device having a first pressure sensor for determining an air pressure of the environment of the device, providing a stationary second pressure sensor in an environment of the device, in particular on a wall or the like, providing a motion sensor, in particular in the form of an acceleration sensor, in the device, determining a motion state of the device on the basis of measured values from the motion sensor, measuring a first air pressure and a second air pressure by means of the first pressure sensor if a standstill of the device was determined as the motion state, a motion of the device having been determined between the two measurements, and determining a relative and/or absolute height at least on the basis of a difference between the measured air pressures.

Description

Title

Method for determining a height of a movable device

State of the art

The invention relates to a method for determining a height of a movable device.

The invention further relates to a movable device.

Although generally applicable to any mobile device, the present invention will be explained with reference to portable devices such as mobile phones or the like.

Although any application is generally conceivable, the present invention is explained with reference to an application for floor detection.

Disclosure of the invention

In order to estimate the floor of a building in which a user is located with his mobile device, it has become known to use a reference sensor in the form of a pressure sensor in the building and to compare the measured values of the same with the measured values of a pressure sensor in a mobile device and from this to determine the floor in which the user is located with his mobile device.

In one embodiment, the present invention provides a method for determining a height of a movable device, comprising the steps

Providing the movable, in particular portable, device with a first pressure sensor for determining an air pressure in the environment of the device, Providing a stationary second pressure sensor in an environment of the device, in particular on a wall or the like

Providing a motion sensor, in particular in the form of an acceleration sensor in the device,

Determining a motion state of the device based on measured values from the motion sensor,

Measuring a first air pressure and a second air pressure by means of the first pressure sensor if the state of movement of the device was determined to be stationary, whereby a movement of the device was determined between the two measurements, and

Determining a relative and/or absolute altitude based at least on a difference in the measured air pressures.

In a further embodiment, the present invention provides a system for determining a height of a movable device, comprising a movable, in particular portable, device, comprising

A first pressure sensor for determining an air pressure in the environment of the device, a motion sensor, in particular in the form of an acceleration sensor, a determination device designed to determine a state of movement of the device based on measured values of the motion sensor, a measuring device designed to measure a first air pressure and a second air pressure by means of the first pressure sensor if a standstill of the device was determined as the state of movement by means of the determination device, wherein a movement of the device was determined between the two measurements and an altitude determination device designed to determine an altitude based on a difference in the measured air pressures and a stationary second pressure sensor in an environment of the device, wherein the second pressure sensor is at least temporarily connected to the movable device. One of the advantages achieved is that high accuracy and reliability can be provided in determining the relative and absolute height. Another advantage is easy implementation.

Further features, advantages and further embodiments of the invention are described below or will become apparent thereby.

According to an advantageous development of the invention, the measured values of the first and second pressure sensors are compared at a common height to determine an absolute height. This allows the absolute height to be determined particularly precisely.

According to a further advantageous development of the invention, measured values from the motion sensor and/or the first and/or the second pressure sensor are processed, in particular filtered, before the height is determined. The advantage is that the accuracy of determining the height can be improved because, for example, outliers etc. are not taken into account when calculating the height.

According to a further advantageous development of the invention, the filtering is carried out using a filter with a finite impulse response, FIR filter, in particular a Gaussian FIR filter. Using FIR filtering, the variance can be reduced or the noise in the measured values of the first and/or second pressure sensor can be reduced or removed. The filtering can be used both when calibrating the two pressure sensors and during normal operation.

According to a further advantageous development of the invention, the filtering is carried out by means of a filter with infinite impulse response, IIR filter, in particular with a first-order IIR filter. The advantages of 11 R filtering are a reduction in the variance when estimating a calibration constant.

According to a further advantageous development of the invention, the filtering of the measured values of the pressure sensors is carried out using the FIR filter and then the filtered measured values are filtered using the II R filter. Advantage The advantage of this is that a particularly accurate estimate of a calibration constant can be achieved. In particular, 11 R filtering is only used during the calibration of the two pressure sensors, whereas Fl filtering is used both during operation and during calibration.

According to a further advantageous development of the invention, the motion sensor detects a movement of the device in the z-direction, vertical direction, to determine the movement state. The advantage of this is that measurements are essentially only taken in one spatial direction, which simplifies the calculation and determination of the movement state.

According to a further advantageous development of the invention, the movement state is determined by comparing the measured values of the motion sensor with a threshold value. This ensures a quick and simple determination of the movement state with sufficient accuracy.

According to a further advantageous development of the invention, the second pressure sensor is connected wirelessly to the movable device for transmitting measured values, in particular via mobile radio, WLAN, Bluetooth or the like. The advantage of this is that changed measured values can be easily transmitted for the reference for height calculation, which overall improves the accuracy in determining the height of the movable device.

According to a further advantageous development of the invention, the absolute height is determined based on the determined height and the height of the second pressure sensor. This enables a simple, fast and sufficiently accurate absolute height determination of the movable device.

Further important features and advantages of the invention emerge from the subclaims, from the drawings and from the associated description of the figures. It is understood that the features mentioned above and those to be explained below can be used not only in the combination specified in each case, but also in other combinations or on their own, without departing from the scope of the present invention.

Preferred embodiments and embodiments of the present invention are shown in the drawings and are explained in more detail in the following description.

It shows in schematic form

Figure 1 is a flow chart of a method according to an embodiment of the present invention;

Figure 2 shows a movement diagram of a movable device according to an embodiment of the present invention;

Figure 3 Measured values of the pressure sensors according to the movement scheme of Figure 2

Figure 4 shows the determined relative height difference of the movable device for the movement scheme of Figure 2;

Figure 5 shows the determined absolute height of the movable device for the movement scheme of Figure 2;

Figure 6 is a flow chart of a calibration method according to an embodiment of the present invention;

Figure 7 shows a flow chart of a measuring method according to an embodiment of the present invention; and

Figure 8 shows a system according to an embodiment of the present invention. Figure 1 shows a flow chart of a method according to an embodiment of the present invention.

Figure 1 shows a flow chart of a method for determining a floor.

The basis for the flow chart is a building with several floors in which a user carries a mobile device in the form of a mobile phone, as shown, for example, in Figure 8.

In order to determine the current floor on which the user is located with his mobile device, firstly, measured values from an acceleration sensor of a movable device (step S1), a pressure sensor of the movable device (step T1) and a pressure sensor arranged stationary in the building (step VI) are read out. The respective measured values are processed, in particular filtered (steps S2, T2, V2).

Based on the filtered measured values of the two pressure sensors, an altitude is calculated (step TV3).

A movement of the mobile device is also calculated based on the filtered measured values of the acceleration sensor (step S3). The determined value for the movement is then compared with a threshold value (step S4). If this is above a threshold value (step S5), step S4 is carried out again. If this is below a threshold value, i.e. the mobile device is stationary, the floor on which the mobile device is located is determined based on the determined height (step TV3).

In particular, the movement can only be based on a movement in the z-direction, ie in the vertical direction, since a movement of the mobile device in one plane, ie on the same floor, does not allow a change of floor. With regard to the acceleration sensor, this can measure an acceleration of the mobile device in all three spatial directions. A threshold value can be specified in each spatial direction, from which a movement of the mobile device is then "recognized" or not. Figure 2 shows a movement diagram of a movable device according to an embodiment of the present invention.

Figure 2 shows an example of a vertical movement VB of a mobile radio device M over various parallel planes E1-E4 (reference number 202) over time 201. The mobile radio device here comprises a pressure sensor and a three-dimensional acceleration sensor. The planes El-E4 are chosen to be equidistant with a distance of 20 cm. However, any other desired distance is also conceivable.

The movement pattern of the mobile device M according to Figure 2 passes through the planes E1-E4 in the following sequences, whereby a horizontal movement of the mobile device takes place in a respective plane E1-E4.

El, E2, E3, E4, El, E3, El, E4 and more

E4, E2, E3, El, E2, E4, El.

In the following figures 3-5, only the first sequence is examined in more detail (to the left of the vertical broken line). Figure 3 shows measured values of the pressure sensors according to the movement pattern in Figure 2, Figure 4 shows a determined relative height difference of the movable device for the movement pattern in Figure 2 and Figure 5 shows the determined absolute height of the movable device for the movement pattern in Figure 2.

Figure 3 shows the already filtered measured values 302 of the pressure sensor in the unit hPa in the mobile device - curve Ml - and the measured values of the stationary pressure sensor - curve M2 over time 301 - here as "sample no.". Figure 4 shows the relative heights 402 calculated from the filtered measured values in the unit meters over time 401 - here as "sample no.". The vertical flanks represent vertical movements VB of the mobile device, the horizontal curves horizontal movements HB. Figure 5 shows the Absolute heights 502 calculated from the filtered measured values in the unit meters over time 501 - here as "sample number." - are shown. The vertical flanks represent vertical movements VB of the mobile device, the horizontal courses horizontal movements HB. The different levels E1-E4 can be assigned to the respective horizontal movements HB where no movement occurs in the vertical direction.

Figure 6 shows a flow chart of a calibration method according to an embodiment of the present invention.

Figure 6 shows a calibration procedure for comparing the measured values of the two pressure sensors. Both pressure sensors are arranged at the same height.

To carry out the calibration procedure, the respective measured values of the pressure sensors are first read out (steps Al, Bl) and then filtered, for example with an FIR filter. The difference between the filtered values is then calculated (step AB3) and filtered with an II R filter, in particular a first-order II R filter with filter constant a (step AB4) and a calibration constant C is determined (step AB5).

This calibration constant C is used to determine the absolute height. If only a relative height is determined, the calibration procedure can be omitted and the constant C can be set to 0. The calibration procedure is only carried out for a few seconds until a calibration constant that is stable over time is available. The variable "x" generally determines the location or position.

Figure 7 shows a flow chart of a method for determining an altitude according to an embodiment of the present invention.

To carry out the procedure, the respective measured values of the pressure sensors are first read out (steps Al, Bl) and then filtered, for example with an FIR filter. The difference between the filtered values is then taking into account the constant determined from the calibration process according to Figure 6 (step A3). In parallel, measured values from the acceleration sensor of the mobile device are used to determine whether there is movement (step CI) or not. If there is no movement (step A4), a height is determined based on the difference and a factor (step A5) and output (step A6)

Figure 8 shows a system according to an embodiment of the present invention.

Figure 8 shows a building H with five sections E1-E5. In the building H, a stationary pressure sensor D1 is provided on the ground floor El. In addition, a user N can move between the floors E1-E5 using an elevator A. The user N carries a mobile device M with him, which has a pressure sensor D2 and an acceleration sensor. The mobile device also has a computing device such as a processor and a memory, which comprise the following units: a determination device 10 designed to determine a state of motion of the device based on measured values from the motion sensor, a measuring device 11 designed to measure a first air pressure and a second air pressure using the first pressure sensor if a standstill of the device was determined as the state of motion using the determination device, and an altitude determination device 12 designed to determine an altitude based on a difference in the measured air pressures.

In summary, at least one of the embodiments of the invention can provide at least one of the following advantages and/or have the following features: accurate height estimation or calculation efficient filtering of measured values for height calculation high accuracy, especially in the cm range when determining height Applicable in many different areas such as

Fitness area, for game controllers or for floor detection

Claims

Expectations

1. A method for determining a height of a movable device (M), comprising the steps

Providing the movable, in particular portable, device (M) with a first pressure sensor (Dl) for determining an air pressure in the environment of the device (M),

Providing a stationary second pressure sensor (D2), in particular on a wall or the like.

Providing a motion sensor (B), in particular in the form of an acceleration sensor in the device (M),

Determining a motion state of the device (M) based on measured values (Cl, Sl) of the motion sensor (B),

Measuring a first air pressure and a second air pressure by means of the first pressure sensor (Dl) when the state of movement of the device (M) was determined to be stationary, wherein a movement of the device (M) was determined between the two measurements, and

Determining a relative and/or absolute altitude (A6, S6) based at least on a difference in the measured air pressures.

2. Method according to claim 1, wherein the measured values of the first and second pressure sensors (Dl, D2) are compared at a common height to determine an absolute height (A6, S6).

3. Method according to one of claims 1-2, wherein measured values of the motion sensor (B) and/or the first and/or the second pressure sensor (Dl, D2) are processed, in particular filtered, before determining the height (A6, S6).

4. The method according to claim 3, wherein the filtering (S2, T2, V2) is carried out by means of a finite impulse response filter, FIR filter, in particular with a Gaussian FIR filter.

5. Method according to one of claims 3-4, wherein the filtering (S2, T2, V2) is carried out by means of an infinite impulse response filter, IIR filter, in particular with a first order IIR filter.

6. Method according to claim 5 and 6, wherein the filtering (S2, T2, V2) of the measured values of the pressure sensors (Dl, D2) is carried out by means of the FIR filter and subsequently the filtered measured values are filtered by means of the IIR filter.

7. Method according to one of claims 1-6, wherein to determine the movement state the motion sensor (B) detects a movement of the device (M) in the z-direction, vertical direction.

8. Method according to one of claims 1-7, wherein the determination of the motion state is carried out by comparing the measured values of the motion sensor (B) with a threshold value.

9. Method according to one of claims 1-8, wherein the second pressure sensor (D2) is connected wirelessly to the movable device (M) for transmitting measured values, in particular via mobile radio, WLAN, Bluetooth or the like.

10. The method according to any one of claims 1-9, wherein the absolute altitude (A6, S6) is determined based on the determined altitude and the altitude of the second pressure sensor (D2).

11. System for determining a height of a movable device (M), comprising a movable, in particular portable, device (M), comprising

A first pressure sensor (Dl) for determining an air pressure in the environment of the device, a motion sensor (B), in particular in the form of an acceleration sensor, a determination device (10) designed to determine a motion state of the device (M) based on measured values of the motion sensor (B), a measuring device (11) designed to measure a first air pressure and a second air pressure by means of the first pressure sensor (D1, D2) when a standstill of the device (M) was determined as the state of movement by means of the determination device (10), wherein a movement of the device (M) was determined between the two measurements and an altitude determination device (12) designed to determine an altitude based on a difference in the measured air pressures, and a stationary second pressure sensor (D2), wherein the second pressure sensor is at least temporarily connected to the movable device (M).