EP3055841A1

EP3055841A1 - Device and method for determining a state of an object which is to be monitored

Info

Publication number: EP3055841A1
Application number: EP14758323.1A
Authority: EP
Inventors: Rolf Kaack; Sergej Scheiermann
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2013-10-07
Filing date: 2014-08-25
Publication date: 2016-08-17
Also published as: DE102013220176A1; WO2015051942A1; JP2016538625A; KR20160067111A; US20160231349A1; CN105612565B; CN105612565A; US10012669B2

Abstract

The invention relates to a device and a method for determining states of an object which is to be monitored, such as for example, a window or a door. The measurement values of several sensors, in particular a magnetometer and an acceleration sensor are consolidated and evaluated together. In order to determine a new state from a group of predetermined states, only actual possible state transitions are taken into account. State transitions which are not possible and/or which are not allowed are not taken into account.

Description

Description title

Device and method for determining a state of an object to be monitored

The present invention relates to an apparatus and a method for determining a state of an object to be monitored.

State of the art

Sensors for condition monitoring of doors and windows are known. These sensors are usually designed in two parts. A first part of the sensor consists of a permanent magnet. A second part of the sensor has a

Magnetic sensor, for example, a reed contact, by the

Permanent magnet in the first part of the sensor can be opened or closed. In this case, a part of the sensor on the movable frame of the monitored window or the door to be monitored must be attached and the other part of the sensor must au outside the movable frame, for example, on the wall, are attached. If the door or the window is closed, then the reed contact is triggered by the magnetic field of the permanent magnet. If the door or the window is opened, the reed contact is not triggered.

The German patent application DE 103 35 126 A1 discloses a device for condition monitoring of an object, in which a reed contact by a

Permanent magnets can be triggered. The device also has a transmitting unit, by which the detected state of the object or a

State change can be transmitted.

There is therefore a need for a one-piece device for

Condition monitoring of an object.

Disclosure of the invention According to a first aspect, the present invention provides a device for determining a state of an object to be monitored, comprising a magnetometer, which is designed to detect a magnetic field and to generate a first measured value

To provide dependence of the detected magnetic field; an acceleration sensor configured to detect an acceleration and to provide a second measured value as a function of the detected acceleration; and one

A processing device configured to detect a state of the object to be monitored using the state of the magnetometer and / or the magnetometer

Accelerometer provided readings from a plurality of

determine predetermined states.

Further, according to another aspect, the present invention provides a method of detecting a state of an object, comprising the steps of detecting a magnetic field and providing a first measurement value corresponding to the magnetic field; detecting an acceleration of the object to be monitored and providing a second measured value corresponding to the detected acceleration; and determining a state of the object to be monitored from a plurality of predetermined states using the first measured value corresponding to the detected magnetic field and / or to the detected one

Acceleration corresponding second measured value.

Advantages of the invention

The present invention is based on the idea of a device for

Condition monitoring of objects in one piece. This will be all

Components required for such condition monitoring are arranged in a common housing. In order to monitor the states, measurements are taken from sensors which can determine a movement and / or a change in position in space without additional aids, such as additional permanent magnets or the like. The measured values of several such sensors are fused together.

The device and the method for determining a state of an object further pursue the approach that the monitoring object can only be in a plurality of previously defined states. Thus, on the basis of the measured values provided by the sensors, in each case one of these predetermined states may be new State of the object to be selected. Thereby the reliability for the

Determination of a state can be further increased by each of the currently determined state of the object is included in the determination of the new state in the determination of a new state.

Furthermore, for the determination of a new state of the object, the possibility of state transitions from a current state to a new state can also be defined and restricted. Thus, allowed or not allowed

State transitions are defined. In this way, the reliability of the state determination can be improved because unauthorized state transitions are excluded from the outset.

Thus, an efficient and very secure condition monitoring of objects can be achieved with a one-piece sensor.

In one embodiment, the device further comprises a memory which is designed to store a state determined by the processing device and measurements corresponding to the specific state of the object from the magnetometer and / or the acceleration sensor. This stored data can not only be stored for logging purposes, but also serve in particular as data for a successive calibration of the condition monitoring. The stored specific states and the corresponding measured values can for example be limited to a predetermined number of data sets. In this case, preferably the oldest previously stored data record can be deleted when a further data record is added.

In one embodiment, the processing device determines the state of the object to be monitored using the states stored in the memory and the corresponding measured values. By using these data stored in the memory, the determination of the states of the object to be monitored can be continuously improved. In particular, this also makes it possible to permanently adapt and re-call state monitoring to changing external influences. Thus, the condition monitor can operate correctly even if the device is placed again on the object to be monitored or the device is placed on another object to be monitored. In one embodiment, the apparatus further includes a communication interface configured to transmit the condition determined by the processing device. Through this communication interface, the specific states and state changes can be passed. For example, it is possible to transmit the data of a specific state to a central building surveillance.

In one embodiment, the communication interface transmits that of the

Processing device certain state wirelessly. Such a wireless

Data transmission allows, in particular for moving objects, a very convenient transfer of the determined status data.

In one embodiment, the magnetometer and / or the acceleration sensor can be deactivated by the processing device. Thus, for example, a

State change of the object are initially monitored by only one sensor. As soon as this one sensor detects a possible state change, the further sensor can then be activated by the processing device. In this way, on the one hand a particularly energy-saving monitoring of the object is possible, while at the same time a reliable determination of changes in state can be performed by the demand-oriented activation of other sensors.

In one embodiment, the monitoring object is a door or a window.

Preferably, the predetermined states include the states opened, closed and tilted. Doors and windows are objects which, due to their clearly defined number of possible states, are particularly well suited for

condition monitoring according to the invention are suitable.

In one embodiment of the method for determining a state of an object, the step for determining a state for each predetermined state calculates a probability and then determines the state with the largest one

Probability. This way, an efficient and reliable determination of states and state transitions can be performed.

The present invention further comprises a building management system having a device according to the invention for determining a state of an object to be monitored. Brief description of the drawings

Other Embodiments Advantages of the present invention will become apparent from the following description with reference to the accompanying schematic drawings. Showing:

Fig. 1 is a schematic representation of a block diagram of an apparatus for

Determining a state of an object to be monitored according to a

embodiment;

FIG. 2 shows a schematic representation of a device for determining a state according to a further embodiment on an opened window; FIG.

3 shows a schematic representation of a device for determining a state according to a further embodiment on a tilted window; and

4 shows a schematic representation of a method for determining a state, such as another embodiment of the present invention

underlying.

Embodiments of the invention

Fig. 1 shows a schematic representation of a block diagram of a device 1 for determining a state of an object to be monitored according to a

Embodiment. The device 1 comprises a magnetometer 1 1 and an acceleration sensor 12, which are connected to a processing device 13. This processing device 13 is further provided with a memory 14 and a

Communication interface 15 connected. The magnetometer 11 is preferably a 3-axis magnetometer. Such a magnetometer detects a magnetic field in all three spatial directions. In particular, such a magnetometer is able to detect changes in the magnetic field in one or more spatial directions separately. Of the

Magnetometer 1 1 gives its measurement results in the form of measurement signals to the processing device 13 on. The magnetometer 1 1 can thus by

continuous monitoring of a static magnetic field, such as the Earth magnetic field, a movement of the magnetometer 1 1 recognize within this magnetic field.

The acceleration sensor 12 is also preferably a 3-axis acceleration sensor that can detect both positive and negative accelerations in all three spatial directions. The acceleration sensor 12 also outputs its measurement results in the form of measurement signals to the

Processing device 13 on. In order to reduce the energy consumption of the device 1 for determining a state, the processing device 13 can thereby deactivate one of the two sensors 11 or 12 in a standby state. For example, the first

Magnetometer 1 1 are disabled and the object to be monitored

monitored exclusively by means of acceleration sensor 12. Recognize the

Acceleration sensor 12 a movement and then passes a corresponding signal to the processing unit 13, then the magnetometer 1 1 is then activated and also supplies measured values to the processing unit 13th

Alternatively, it is also possible to first deactivate the acceleration sensor 12 and to evaluate only measuring signals from the magnetometer 11. In this case, the acceleration sensor 12 can be activated after a movement of the object to be monitored has been detected by the magnetometer 11, in order to evaluate the measuring signals of the acceleration sensor 12 together with the measuring signals of the magnetometer 11.

If the processing device 13 receives measuring signals from the magnetometer 11 and / or the acceleration sensor 12 which indicate a movement of the object to be monitored, these signals are evaluated by the processing device 13 and then a possible new state of the object to be monitored is determined. The measurement signals of the magnetometer 1 1 and the

Acceleration sensor 12 evaluated together.

The processing device 13 analyzes the measurement signals provided by the magnetometer 11 and the acceleration sensor 12 and then determines from a plurality of predetermined possible states of the object to be monitored using the provided measurement signals, a possible new state of the object to be monitored.

If, for example, the object to be monitored is a window, then this object can normally have three possible states: closed, opened or tilted.

FIG. 2 shows a window 2 in an opened state. In this case, a device 1 for determining a condition is attached to the window 2. To open the window 2, the window is thereby rotated on the hinges (not shown) about the Z-axis.

FIG. 3 further shows a window 2 in a tilted state. In this case, the window 2 is tilted on further hinges (also not shown) about the X-axis. The window shown in FIGS. 2 and 3 can therefore assume the three states of being opened, closed or tilted, it not being possible to move from each state directly to any other state. If the window 2 is in an open state, for example, then it is not possible to switch directly to the tilted state. Rather, it is imperative that the window 2 is closed before. Likewise, conversely, the transition from the tilted state is possible only in the closed state. Only then can the window 2 be opened.

The processing device 13 takes into account these additional constraints by which allowed or not allowed state transitions are defined. The

Processing device 13 will therefore in a known current state of the object to be monitored 2 using the provided measurement signals only determine those new states, which are also allowed in accordance with the predetermined constraints. Unauthorized state transitions, which rule out one or more of the predetermined states on the basis of the currently determined state, mean that the corresponding excluded predefined states can not be determined as new states.

The processing device 13 can for determining the new states of the monitoring object 2 for all predetermined states, preferably at least for all allowed predetermined new states based on the provided measurement signals each calculate a probability. For the

Calculation of the probabilities for the predetermined states can be analyzed, for example, the waveforms of magnetometer 1 1 and / or acceleration sensor 12 during a period of time. The signal curves for all spatial directions can be separated or if necessary also analyzed together. Also, an evaluation of the amounts of the waveforms for all spatial directions together or separately is possible. Furthermore, the processing device 13 can also only one

Evaluate changes in the measured values of magnetometer 1 1 and / or acceleration sensor 12. Here, too, an evaluation of the measured values for all spatial directions is possible together or separately. Likewise, it is possible to evaluate only the amounts of the measured values.

For example, in a state change from a closed window 2 to an opened window 2, an acceleration in the Y direction and X direction would be detected, while in the Z direction the acceleration is (almost) zero. By the magnetometer 1 1, a corresponding variation of the monitored geomagnetic field can be detected by the change in position of the device 1.

The processing device 13 can directly evaluate the measurement signals from the magnetometer 11 and the acceleration sensor 12 and then determine, based on predetermined rules, one in the predetermined states of the object 2 to be monitored.

Furthermore, it is also possible for the determination of the states of the object 2 to be monitored to have already been preceded measured values of magnetometer 11 and

To use acceleration sensor 12. For this purpose, the previous measured values of magnetometer 11 and acceleration sensor 12 can be stored in the storage device 14. The processing device 13 can read out these stored measured values and the corresponding state of the object from the memory device 14 and use them to determine a new state of the object.

For example, the measured values or signal profiles currently provided by magnetometer 11 and acceleration sensor 12 can be stored with previously stored data

Reference values are compared. For example, a correlation function or another analysis for comparing the current measured values with the reference values be calculated. For this purpose, the mean value of several reference values can also be compared with the current measured values.

For example, for each of the predetermined possible states of the

monitoring object 2 are stored a matrix X with measured values, as shown in the following formula:

where A _xi , A _yi and A _{zi are} respectively the measured values of the acceleration sensor 12 and M _xi , M _yi and M _{zi are} respectively the measured values of the magnetometer 11 in the respective spatial directions x, y and z. The counter i denotes the individual measurements. The term "state" stands for the individual predetermined states that the

can take over a waxing object. If the maximum storage capacity of the memory 14 is reached and a further measurement or state determination is made, preferably the line with the oldest measurement is deleted and all other lines are shifted down by one line, so that the most recent measurement can be inserted in the first line , Preferably, a separate matrix X (state) is created for each predetermined state of the object 2 to be monitored.

In this way, the device 1 for determining the state of an object during operation can calibrate itself. Thus, in advance, no specific

Adaptation of this device 1 to the respective site required. If the framework conditions change during operation, then the device 1 can adapt itself automatically to the changed framework conditions. Thus, for example, a metallic body placed nearby, for example a cabinet, would bring about changes in the earth's magnetic field detected by the magnetometer 11. Due to the successive automatic calibration, this disturbance can be compensated very quickly. Also possibly occurring

Wear phenomena in the joints along which the window 2 to be monitored moves, which can lead to variations in the acceleration when opening, closing and tilting a window 2, are thus compensated. The states of the object 2 to be monitored determined by the processing device 13 can be forwarded to a communication interface 15. The communication interface 15 then transmits the determined states or a determined state change to a suitable receiver. Basically, a wired data transmission is possible. In this case, the power supply of the device 1 can also take place simultaneously via the wired data transmission. Preferably, however, the data transmission from the communication interface 15 to the remote station will be via a wireless radio link. For example, the data transmission by means of a known protocol such as DECT, Bluetooth, WLAN, etc. take place. In this case, the device 1 is preferably powered by a battery.

The remote station can be, for example, a local radio receiver or preferably the receiver of a central building management system. Preferably, the radio signals of several devices 1 for determining states of objects to be monitored can be received and evaluated by the corresponding receiver. In this case, automatic networking of the individual devices 1 with one another and / or with the central receiving point is possible, in particular in the case of a wireless transmission.

FIG. 4 shows a schematic representation of the sequence of a method 100 for determining a state of an object to be monitored. In step 1 10, a magnetic field, preferably the earth's magnetic field, detected and one to the detected

Magnetic field corresponding measured value provided. In step 120, a

Acceleration of the monitored object detected and provided a corresponding to the detected acceleration second measured value. Subsequently, in step 130, a state of the monitoring object is selected from a plurality of

determined predetermined states using the first measured value corresponding to the detected magnetic field and / or the second measured value corresponding to the detected acceleration. In this case, the step 130 may preferably have a for each of the predetermined states

Calculate probability. Preferably, only probabilities for calculates the possible states that are possible based on the current state of the object as previously determined. Subsequently, in this case, the state is determined as a new state of the object to be monitored, which has the greatest probability.

In summary, the present invention relates to a device a method for determining states of an object to be monitored, such as a window or a door. The measured values of several sensors, in particular a magnetometer and an acceleration sensor, are fused and evaluated together. In order to determine a new state from a group of predetermined states, only actual state transitions are considered. Not possible or not allowed state transitions remain

unconsidered.

Claims

claims

1 . Apparatus (1) for determining a condition of an object (2) to be monitored, comprising: a magnetometer (11) adapted to detect a magnetic field and to provide a first measured value in response to the detected magnetic field; an acceleration sensor (12), which is designed to detect an acceleration and to provide a second measured value as a function of the detected acceleration; and a processing device (13) which is designed to determine a state of the object to be monitored using the measured values provided by the magnetometer (11) and / or the acceleration sensor (12) from a plurality of predetermined states.

A device (1) according to claim 1, comprising a memory (14) adapted to determine a condition determined by the processing means (13) and to be determined

State of the object corresponding measured values from the magnetometer (1 1) and / or the acceleration sensor (12) to store.

3. Device (1) according to claim 2, wherein the processing device (13) determines the state of the object to be monitored (2) using the stored in the memory (14) states and the corresponding measured values.

4. Device (1) according to one of claims 1 to 3, with a

Communication interface (15) adapted to receive from the

Processing device (13) to transmit certain state.

5. Device (1) according to claim 4, wherein the communication interface (15) wirelessly transmits the state determined by the processing device (13).

6. Device (1) according to one of claims 1 to 5, wherein the magnetometer (1 1) or the acceleration sensor (12) by the processing means (13) is deactivated.

7. Device (1) according to one of claims 1 to 6, wherein the object to be monitored (2) is a door or a window.

8. Building management system with a device (1) according to one of the preceding claims 1 to 7.

9. A method (100) for determining a state of an object to be monitored (2), comprising the steps of:

Detecting (1 10) a magnetic field and providing a first measured value corresponding to the detected magnetic field;

Detecting (120) an acceleration of the object to be monitored and providing a second measured value corresponding to the detected acceleration; Determining (130) a state of the object to be monitored (2) from a plurality of predetermined states using the first measured value corresponding to the detected magnetic field and / or the second measured value corresponding to the detected acceleration.

The method of claim 9, wherein the step (130) of determining a state for each predetermined state calculates a probability and determines the state of greatest likelihood.