U.S. patent application number 17/219090 was filed with the patent office on 2021-10-14 for method and system for determining at least one physical value.
The applicant listed for this patent is Balluff GmbH. Invention is credited to Albert Dorneich, Andrea Hiller-Brod, Stephan Langer, Jorg Maier, Martin Osterfeld, Roland Schafer, Jochen Streib.
Application Number | 20210318150 17/219090 |
Document ID | / |
Family ID | 1000005550679 |
Filed Date | 2021-10-14 |
United States Patent
Application |
20210318150 |
Kind Code |
A1 |
Osterfeld; Martin ; et
al. |
October 14, 2021 |
Method and System for Determining at Least One Physical Value
Abstract
The at least one value is respectively determined from at least
one measured value of the sensors (20-29) in a method for
determining at least one physical value in a space (10) in which
several sensors (20-29) are arranged which are set up to measurer
the at least one value, for several positions (30) in the space
(10) where there is no sensor (20-29). A system which is set up in
order to determine the at least one physical value in the space
(10) has several sensors (20-29) which are arranged in the space
(10). Furthermore, it has a database, in which information about
the space (10) is stored, and a computer which is set up in order
to determine the at least one value by means of the method.
Inventors: |
Osterfeld; Martin;
(Schlaitdorf, DE) ; Langer; Stephan; (Filderstadt,
DE) ; Schafer; Roland; (Rottweil, DE) ;
Dorneich; Albert; (Ostfildern, DE) ; Hiller-Brod;
Andrea; (Weilheim, DE) ; Maier; Jorg;
(Filderstadt, DE) ; Streib; Jochen; (Ostfildern,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Balluff GmbH |
Neuhausen a.d.f. |
|
DE |
|
|
Family ID: |
1000005550679 |
Appl. No.: |
17/219090 |
Filed: |
March 31, 2021 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G01D 21/02 20130101 |
International
Class: |
G01D 21/02 20060101
G01D021/02 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 8, 2020 |
DE |
102020109859.6 |
Claims
1. A method for determining at least one physical value in a space
(10) in which several sensors (20-29) are arranged, which are set
up to measure the at least one value, said method comprising:
wherein the at least one value is respectively determined from
measured values of the sensors (20-29) by means of interpolation
and/or extrapolation for several positions (30) in the space (10)
where there is no sensor (20-29) or the at least one value is
respectively determined from measured values of the sensors (20-29)
by means of a physical model or a logical model; the at least one
value determined by means of interpolation and/or extrapolation or
by means of a physical model or a logical model is compared to a
perturbation value or a range of a perturbation value which is
stored in the space (10) for its position or several different
values determined by means of interpolation and/or extrapolation or
by means of a physical model or a logical model are compared to a
perturbation pattern which is stored for this position; and wherein
an anomalous state is concluded depending on a result of the
comparison.
2. The method according to claim 1, wherein a 3D value map (55) is
compiled from several values.
3. (canceled)
4. The method according to claim 1, wherein at least one linear
function, polynomial function or spline function is used during the
interpolation and/or extrapolation.
5. (canceled)
6. The method according to claim 1, wherein the model contains
geometries of objects (11) in the space (10).
7. The method according to claim 6, wherein the model contains
material data of the objects (11).
8. The method according to claim 1, wherein the physical or logical
model contains data about sources and/or sinks of physical
parameters in the space (10).
9. The method according to claim 1, wherein the physical or logical
model contains data about the properties of a shell of the
space.
10. (canceled)
11. (canceled)
12. The method according to claim 1, further comprising a computer
program which is set up in order to carry out each step of the
method.
13. The method according to claim 12, further comprising a
machine-readable storage medium on which the computer program is
stored.
14. A system which is set up in order to determine at least one
physical value in a space (10), said system comprising: several
sensors (20-29) which are arranged in the space (10); a database
(41) in which information about the space (10) is stored; and a
computer (50) which is set up to determine the at least one value
by respectively determining at least one value from measured values
of the sensors (20-29) by means of interpolation and/or
extrapolation for several positions (30) in the space (10) where
there is no sensor (20-29) or the at least one value is
respectively determined from measured values of the sensors (20-29)
by means of a physical model or a logical model; comparing the at
least one value determined by means of interpolation and/or
extrapolation or by means of a physical model or a logical model to
a perturbation value or a range of a perturbation value stored in
the space (10) for its position or comparing several different
values determined by means of interpolation and/or extrapolation or
by means of a physical model or a logical model to a perturbation
pattern stored for this position; and an anomalous state is
concluded depending on a result of the comparison.
15. The system according to claim 14, comprising: an evaluation
unit (70) which is set up to conclude on an anomalous state from a
comparison of at least one value with a perturbation value or a
range of a perturbation value or several values with a perturbation
pattern; and an emitting unit (80), by means of which perturbation
values and/or perturbation patterns can be input into the
database.
16. The system according to claim 15, wherein the evaluation unit
(70) is set up in order to emit an error message (90).
17. The system according to claim 14, further comprising: a linking
unit (60) which is set up in order to link several of the values
determined by the computer (50).
Description
[0001] The present invention relates to a method for determining at
least one physical value in a space. Furthermore, the present
invention relates to a computer program set up to carry out each
step of the method, and a machine-readable storage medium, on which
the computer program is saved. Finally, the present invention
relates to a system by means of which the at least one physical
value can be determined.
PRIOR ART
[0002] In the food industry, process safety plays a primary role.
On the one hand, it is the prerequisite for compliance with
statutory regulations or guidelines, for example relating to
hygiene, and on the other hand that, during the manufacturing
process, food is treated in such a way that a desired or required
final quality can be achieved. This requirement leads to a
plurality of parameters of the food manufacturing process being
detected virtually completely by sensor technology. In order to
ensure comprehensive transparency and visibility of the state of a
system and thus to recognise anomalies in good time and, ideally,
to spatially isolate the cause of the anomaly, the use of a large
number of sensors is necessary.
[0003] EP 1 157 319 B1 describes a system and a method for
preparing food using a precise online controller for a heat
transfer process. The food preparation system comprises a heating
chamber and/or cooling chamber, a sensor and a controller. During a
phase of the remote transfer process, the chamber transfers heat to
or from the food. The sensor detects the actual temperature in the
heating chamber and/or cooling chamber in real time. The controller
controls the heating chamber and/or cooling chamber according to a
planned time/temperature profile. The method simulates the internal
temperature of the food in real time based on the actual
temperature of the chamber. The calculation of the internal
temperature is based on the finite-element method.
[0004] An object of the present invention is to enable the
determination of at least one physical value even for spaces with
complex geometry at positions where no sensor is provided for
measuring the at least one value. A further object of the invention
is to provide a system which makes it possible to carry out the
method.
DISCLOSURE OF THE INVENTION
[0005] In one aspect of the invention, this object is solved by a
method for determining at least one physical value in a space in
which several sensors are arranged. These sensors are set up to
measure the at least one value. This physical value can be, for
example, a temperature value or a value of humidity. Furthermore,
the physical value can be, for example, a brightness, a vibration,
a pressure or an inclination. For several positions in the space
where there is no sensor, the at least one value is respectively
determined from measured values of the sensors. This makes it
possible to provide virtual measurements for the positions and thus
to obtain information about the at least one value in different
positions inside the space without having to provide a sensor at
each of these positions.
[0006] If the method is to be used to determine several different
physical values, such as temperature and humidity, for example,
then it is preferred that the sensors each contain several sensor
elements, wherein each sensor element enables the measuring of one
of the values. In this way, a plurality of different physical
values can be determined without requiring a large number of
sensors to do so. In addition, this ensures that all different
values are respectively measured at the same positions.
[0007] Preferably, a 3D value map is compiled from several values.
This means that at least one value is allocated to each
three-dimensional position in the space. The three-dimensional
image, obtained in this way, of the value distribution can be
regarded as a virtual three-dimensional sensor. By means of a
regular retrieval of the 3D value map, anomalies can be recognised
in good time and can be spatially isolated using suitable methods.
Unusual states of the at least one physical value can also be
identified at locations where no sensor is attached and can thus
support the machine efficiency and process safety in the space.
[0008] In an embodiment of the method, the at least one value is
determined by means of interpolation and/or extrapolation from the
measured values. This makes it possible to simply determine the at
least one value with the aid of a mathematic model without further
information about the space having to be known for this.
[0009] In the interpolation or extrapolation, a linear function, a
polynomial function or a spline function is preferably used. The
function can be chosen, in particular, depending on the number and
arrangement of the sensors.
[0010] If a higher degree of accuracy is desired during the
determination of the at least one value, then it is preferred in
another embodiment of the method that the at least one value is
determined by means of a physical model or a logical model. Model
properties can be provided to a computer, for example, before the
start of the method via an interface, on which computer the method
is carried out. This can be carried out in the form of CAD data,
for example. In another alternative, it is possible to determine
the model properties by means of the sensors using a learning
method. This learning method can be carried out when the space for
this is brought into a defined state. For example, for this, a
machine arranged in the space can be heated to a defined
homogeneous temperature when the physical value is a temperature.
Various objects in the space can also be heated to different
defined temperatures. The model properties can then be determined
by means of predictions from the measured values of the sensors
(curve fitting). If the physical value is a humidity, a defined
state can be achieved, for example, by the space being ventilated
to achieve homogeneous humidity distribution.
[0011] It is preferred that the model contains geometries of
objects in the space. The objects can be, for example, walls which
delimit the space, windows which enable an air exchange with the
surroundings, fans which cause air movement, or heaters which emit
heat. In doing so, the influence of these objects on the
propagation of heat or humidity, for example, between two sensors
can be taken into consideration.
[0012] Furthermore, it is preferred that the model contains
material data of the objects. If the physical value is the
temperature, then the heat conductivity and the heat capacity of
the objects are material data relevant to the model. If the value
is the humidity, then the impermeability of the objects, for
example, is relevant in order to be able to determine the humidity
distribution in the space.
[0013] Furthermore, it is preferred that the model contains data
about sources and/or sinks of physical parameters in the space. On
the one hand, these physical parameters can be the value itself,
i.e. heat or humidity, for example, yet on the other hand,
parameters which influence the distribution of the value in the
space, such as air currents, for example.
[0014] The physical model can be, in particular, a numerical or an
analytical model. In an embodiment of the method in which a
numerical model is used, the space can be depicted in particular by
finite elements, the measurements of which being allocated to the
sensors as number values. At points where there is no sensor, the
values are then calculated numerically with the aid of the measured
sensor values by using the laws of physics. If the physical value
is the temperature, then the heat equation, for example, can be
used for this. If the physical value is the humidity, then the laws
of diffusion, for example, can be used.
[0015] In an embodiment of the method in which the model is an
analytical model, the spatial dependencies are depicted, in
particular by mathematical functions which contain freely
selectable parameters. The mathematical functions are the result of
the laws of physics. The mathematical functions can be polynomials,
for example. In this case, the freely selectable parameters are
coefficients of the polymers, for example. The parameters can be
determined based on the values measured by means of the sensors. At
positions where there is no sensor, the values can then be
calculated from the functions with the aid of known parameters.
[0016] In an embodiment of the method, the at least one value of a
position is compared to a perturbation value or a range of the
perturbation value, which is stored for its position in the space.
Depending on a result of the comparison, an anomalous state is
concluded. In this way, an anomalous state can be recognised in
good time when this is already obvious in the space at a certain
position because of a single value without a sensor having to be
applied at this position.
[0017] In another embodiment of the method, values are determined
for several positions in the space and compared with a perturbation
pattern which is stored for these positions. Depending on a result
of the comparison, an anomalous state can be concluded. This
embodiment of the method makes use of the fact that values can be
provided for a plurality of positions without requiring sensors at
these positions for this. Anomalous states can then also be
recognised, which do not become clear by means of a single value in
a single position, but rather only by a pattern of values at
different positions which refer to an anomalous state only in this
combination. Here, the pattern can consist both of several values
of the same physical quantity at different positions in the space
and of a combination of different physical quantities. Thus, the
method makes it possible to also recognise an anomalous state, for
example, which is characterised by a certain temperature at a point
in the space and a certain level of humidity at another point in
the space occurring at the same point in time.
[0018] Recognising anomalous states can be used, in particular, in
order to introduce immediate counter-measures. But this can also be
used, for example, in order to undertake a causal analysis by it
being considered, in the event of the anomalous state occurring
several times, whether this always occurs at certain points in
time.
[0019] In a further aspect of the invention, a computer program is
provided which is set up to carry out each step of the method, in
particular when it runs on a computer or electronic control unit.
It makes it possible to implement different embodiments of the
method on a computer without having to undertake constructive
changes on it. In order to install the computer program on the
computer, in yet another aspect of the invention, a
machine-readable storage medium is provided on which the computer
program is stored.
[0020] Moreover, in an aspect of the invention, the object is
solved by a system which is set up in order to determine at least
one physical value in a space. This system has several sensors
which are arranged in the space. Moreover, it has a database in
which information about the space is stored. Finally, it has a
computer which is set up in order to determine the at least one
value by means of the method.
[0021] The information about the space preferably comprises at
least at which position in the space each individual sensor is
arranged and which physical parameter it measures. When the
determination of the at least one value is provided in the method
by means of a physical model or a logical model, then it is further
preferred that physical properties of the media and materials lying
between the sensor positions are stored in the database. The
physical properties can be, in particular, mechanical or
thermodynamic properties, such as heat conductivity, for example.
Furthermore, it is preferred that the information includes
properties of a shell of the space. If the space is a building,
then these would be properties of the building shell, for
example.
[0022] In order to not only be able to determine the at least one
physical value by means of the system, but rather to also be able
to evaluate it to recognise anomalous states, it is further
preferred that the system has an evaluation unit, which is set up
in order to conclude an anomalous state from the comparison of a
value with a perturbation value or a range of a perturbation value
or several values with a perturbation pattern. Moreover, the
evaluation unit is preferably set up in order to emit an error
message. Furthermore, in this case, the system comprises an input
unit by means of which perturbation values and/or perturbation
patterns can be input into the database. Moreover, it is preferred
that the database contains information about machines that are
arranged in the space. Perturbation values and perturbation
patterns can be derived from tolerances, relating to the physical
value, of the individual machines. Moreover, physical properties of
the materials of which the machines consist can be stored.
[0023] Finally, it is preferred that the system has a linking unit
which is set up in order to link several values determined by the
computer. This linking can be used as the foundation for a quick
comparison of several values with a perturbation pattern. For this,
it is further preferred that linking rules for the combination of
several values are contained in the database.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Exemplary embodiments of the invention are depicted in the
drawings and explained in more detail in the description below.
[0025] FIG. 1 schematically shows a space in which a physical value
can be determined by means of a method according to an exemplary
embodiment of the invention.
[0026] FIG. 2 shows a value map which can be compiled by means of a
method according to an exemplary embodiment of the invention.
[0027] FIG. 3 schematically shows a system according to an
exemplary embodiment of the invention.
EXEMPLARY EMBODIMENTS OF THE INVENTION
[0028] In an exemplary embodiment of the invention, a machine 11 is
arranged in a space 10, on the surface of which machine ten sensors
20 to 29 are arranged. The sensors 20 to 29 are temperature
sensors. In a first exemplary embodiment of the method, the
temperature at all positions of the space 10 where none of the
sensors 20 to 29 are arranged is determined by means of a
mathematical model from the measurements of the sensors 20 to 29.
For example, the value of the temperature at position 30 can be
determined by interpolation from the measurements of the first
sensor 20 and the second sensor 21. When the first sensor 20
measures a temperature of 8.degree. C. and the second sensor 21
measures a temperature of 12.degree. C., then a temperature of
10.degree. C. at position 30 emerges as a result of linear
interpolation.
[0029] In a second exemplary embodiment of the method, four sensors
20 to 23 are arranged in the space 10. A 3D value map is generated
from the measurements of these four sensors, on which map a
temperature value is allocated to each position. FIG. 2 shows a
section along an x-y plane, through the 3D value map. Here, the
temperature T is visualised as a third coordinate via the
interface. In further exemplary embodiments of the method, the
temperature can be depicted by colour coding, for example as a
spectral course or hot-cold course or, as a number value, projected
into a three-dimensional image of the space 10 as a number cloud.
If this visualisation method were applied to the space 10 depicted
in FIG. 1, then a temperature value of 10.degree. C., for example,
would be projected at position 30 on the surface of the machine
11.
[0030] In a third exemplary embodiment of the method, a 3D value
map is compiled by means of a physical or logical model. To do so,
a system is used which is depicted in FIG. 3. This has a database
40 with several partitions 41 to 46. In the first partition 41, the
positions of all sensors of the system are stored in three
dimensions in the space 10. In this exemplary embodiment, the
system has four sensors 20 to 23. Furthermore, it is stored as to
which physical parameter is measured by these sensors. In this
exemplary embodiment, all sensors 20 to 23 measure the temperature.
The second partition 42 stores the heat conductivity between the
positions of the sensors 20 to 23. The third partition 43 contains
information about the heat conductivity and heat capacity of the
shell of the space 10. Information about machines and objects
arranged in the space 10 is stored in the fourth partition 44. The
fifth partition 45 contains linking rules for linking temperature
values of different positions in the space 10. The sixth partition
46 contains perturbation patterns for individual combinations of
temperature values and their correlation to known error
descriptions of the machines arranged in the space 10.
[0031] A computer 50 is provided in order to compile a 3D value map
55 of the temperature in the space by using the measurements of the
sensors 20 to 23 and the information from the first four partitions
41 to 44 and by using a physical or logical model. In the same way
as in the second exemplary embodiment, this can be visualised. A
linking unit 60 links individual values from the value map 55 to
form patterns by using the linking rules from the fifth partition
45. In an evaluation unit 70, these patterns are compared to
perturbation patterns from the sixth partition 46. If a sufficient
accordance between a pattern compiled by the linking unit 60 and
one of the perturbation patterns is recognised, then an error
message 90 is emitted, wherein the error linked to the perturbation
pattern in the sixth partition 46 is labelled. An emitting unit 80
makes it possible to add further perturbation patterns in the sixth
partition 46 as needed.
* * * * *