DE102014008939A1 - Method and device for determining the movement of a person - Google Patents

Abstract

In a method for determining a movement of a person (30) by means of a test track (21) with a test track beginning (22) and a test track end (23) results in a relatively simple, straightforward and cost feasibility, without the constant use of expensive service personnel required by the following method steps: detecting a mean speed of movement of the person (30) within the test track (21); - detecting steps of the person (30) within the test track (21); and determining an average stride length of the person (30) from the average travel speed and from the detected number of steps within the test route (21). Furthermore, the present invention relates to a corresponding device (1).

Description

The invention relates to a method and a device for determining a locomotion of a person or a subject along a test or measurement path.

The measurement of locomotion is playing an increasingly important role in clinical trials and epidemiological studies of both chronic degenerative diseases, such as multiple sclerosis or Parkinson's disease, as well as general clinical or medical observation of individuals. By "locomotion" is thereby the quality of locomotion in one or more gaits, such. As walking or running, understood. For example, when walking, important quantitative parameters for characterizing this quality are the (average) walking speed and the (average) stride length. A number of studies have shown that a decrease in walking speed in the elderly is an indication of the likelihood of expected falls and even mortality.

The walking speed is usually determined in the clinical environment by means of a stopwatch and a measured distance or with the aid of two light barriers or even more elaborate methods by means of 3D tracking or force plates in professional running laboratories.

From the US 5,952,585 Such a force plate is known, wherein a plurality of pressure sensor elements are arranged in an electronic doormat to detect the footprints of a subject as a function of time in cooperation with a process computer. Depending on the location of the respectively triggered sensor elements, the time-dependent detection provides information about the geometry of the respective footprint, the speed and the step length of the subject.

A disadvantage of this prior art, however, is that this device is relatively expensive due to the technically complex production and the device is cumbersome to handle, since a process computer for detecting the large amount of data supplied by the plurality of sensor elements is required and systemic addition to the device install. In addition, for the operation of the process computer and because of the necessarily required wiring of the plurality of sensor elements with the process computer, the presence of trained personnel in the implementation of the measurement method is necessary.

The DE 696 28 407 T2 describes a device ("pedometer") with which only the number of steps of a subject can be detected. Unsatisfactory here is that beyond the detection of the step number addition, by design, no further information about the speed of the subject with this device can be achieved.

Finally, out of the DE 10 2005 019 924 A1 an activity measuring device using acceleration sensors for determining the degree of disability of MS patients. Here, the activity measuring device is arranged on and / or in a belt buckle of a belt attachable to the body of the subject. Furthermore, the activity measuring device has acceleration sensors for acceleration detection in all three orthogonal spatial directions.

The prior art has the following disadvantages in particular. Walking speed measurements depend on a variety of factors, in particular the total length of the track (relative error becomes smaller with longer distance, but fatigue can affect the result, long distances are often impractical), the initial phase (acceleration) vs. start of measurement after start-up phase), the precision of the time measurement (interrater variability). Different intermediate results are often noted down manually, so that the measurement procedure and the subsequent data management is time-consuming and carries the risk of transmission errors.

There is therefore a need for an easily manageable, short-distance feasible, standardized or objective, valid, automatic measurement of the walking speed, the result of which can be electronically stored and transmitted, both for use in the clinic and, for example, in the field. At home or in a nursing home.

The invention is therefore based on the object of specifying or to provide a method and a device for determining the locomotion of a person, with which the determination of the locomotion of the person is relatively simple, straightforward and inexpensive feasible.

• – Erfassen einer mittleren Fortbewegungsgeschwindigkeit der Person innerhalb der Teststrecke;
• – Erfassen von Schritten der Person innerhalb der Teststrecke; und
• – Bestimmen einer mittleren Schrittlänge der Person aus der mittleren Fortbewegungsgeschwindigkeit und aus der erfassten Anzahl von Schritten innerhalb der Teststrecke.

The object is achieved in terms of process engineering in that the locomotion of a person is determined by means of a test track with a test track beginning and a test track end by the following method steps:

• - Detecting a mean speed of movement of the person within the test track;
• - detecting steps of the person within the test track; and
• Determining an average step length of the person from the average travel speed and from the detected number of steps within the test track.

The average rate of travel, or in the preferred case of walking, the average walking speed, is a suitable parameter for assessing the quality of a patient's locomotion. According to the invention, the mean travel speed is also used to determine the mean stride length, so that two relevant parameters for locomotion can be determined with a simple structure. It is therefore proposed a method that allows an objective measurement and evaluation of the locomotion of a person. Here, the constant use of expensive service personnel is not required. The detection of the speed of movement can also be automated.

Preferably, the length of a first part of the person step into the test track and the length of a last step of the person from the test track out in the determination of the average step length is disregarded. This makes the measurement of mean stride length much more accurate because only the "real" or complete steps are used to determine it. Also, an acceleration of the leg by the initial entry into the test track and a slowdown by leaving the test track is kept out of the measured data. Although the length of the test track should be relatively large (in relation to the average stride length) for reasons of measurement accuracy, this is space-consuming. However, if the length of the test track is therefore relatively small, the accuracy of determining the average stride length increases significantly.

According to an advantageous embodiment of the method according to the invention, this further comprises detecting a start time t _start when the person passes the test track beginning and detecting a stop time t _stop when the person passes the test track end. In this case, the average speed of travel v of the person within the test track is detected by calculation from the start time, the stop time and the length d of the test track. The calculation is done simply by the formula v = (t _stop - _start ) / d. Therefore, it is basically sufficient for the calculation of the average speed of movement, if only the difference between start and stop time is detected. For the detection of the temporal measuring interval, however, the individual recognition of the start and the stop time is advantageous, since in this way only steps within the test track can be selected for the determination of the average step length.

According to a structurally preferred variant of the invention, the steps are detected by at least one acceleration sensor attached to the person. It is preferred that an occurrence of the person on the test track is detected by the at least one acceleration sensor for detecting the steps. To detect N steps, therefore, an occurrence of the person is detected (N + 1) times. Advantageously, three acceleration sensors are used for all three spatial directions, the vertical acceleration being most important for the detection of an occurrence and thus of a step. This exceeds a threshold when a step is detected. The detection of the acceleration in the other two spatial directions has the advantage of even more accurate step detection, z. In a case where the acceleration sensors are not exactly aligned, d. H. whose arrangement is tilted or inclined.

Advantageously, when detecting steps of the person within the test track, the corresponding times of the steps are also recorded. Basically, it is sufficient for the present invention, if only the time of the first and last occurrence is detected, since only with these values together with the detected number of N + 1 appearances, i. H. N steps, an average for the stride length can be determined. Not only to determine the first and last step within the test track, the detection of all times is preferred, but also to adaptively make corrections to the threshold for the acceleration (s) triggering a step detection, if necessary.

According to an advantageous development of the invention, a step is detected as such only if a predetermined time period has passed after the immediately preceding detected step. In the first tests it has been found that in a single occurrence, an acceleration value exceeds a corresponding threshold several times, so that an occurrence can easily be counted several times, which then significantly distorts the determination of the step length. Therefore, it is preferable to detect a subsequent occurrence only after a preset period of preferably a few hundred milliseconds (for example, about 330 ms).

Preferably, the average stride length is determined from the mean travel speed and the length of the route between the first and last occurrences of the person detected within the test route. The route used for the Calculation of the mean stride length is therefore only a partial area of the entire test track, of which a start and end area is indeed used for the measurement of the average speed of movement, but not for the determination of the average stride length.

Finally, it is preferred that the mean step length s is determined according to the following formula: s = (d - v (t ₁ - t _start + t _stop - _{N + 1} )) / N where v is the average speed, N is the number of complete steps of the person within the test track, t _start the start time, t _stop the stop time, t _{1 is} the time of the first occurrence detected within the test track, t _{N + 1} , the time of the last within the test track detected occurrence, and where d is the length of the test track. The expression (d - v (t ₁ - t _start + t _{stop N + 1} )) / N represents the length of the distance between the first and the last occurrence within the test track. Dividing this value by the number of steps N, where N is a natural number greater than one, we obtain a value for the average step length s.

• – Mittel zum Erfassen einer mittleren Fortbewegungsgeschwindigkeit der Person innerhalb der Teststrecke;
• – Mittel zum Erfassen von Schritten der Person innerhalb der Teststrecke; und
• – Mittel zum Bestimmen einer mittleren Schrittlänge der Person aus der mittleren Fortbewegungsgeschwindigkeit und aus der erfassten Anzahl von Schritten innerhalb der Teststrecke.

Furthermore, the object is achieved in terms of device technology in that in order to determine a movement of a person by means of a test track with a test track beginning and a test track end, the device has the following:

• - means for detecting an average speed of movement of the person within the test track;
• - means for detecting steps of the person within the test track; and
• - means for determining an average step length of the person from the mean travel speed and the detected number of steps within the test track.

In one embodiment, the device according to the invention can be embodied as a measuring belt, which is carried by a person while he is moving in the test track. In this case, the measuring belt can have all the necessary means to carry out the method according to the invention. It is also possible for the device according to the invention to be part of a measuring system, for example part of a gear laboratory, which has a test section in which the device according to the invention performs a measurement and / or evaluation.

Measurement and evaluation can also be performed on different devices, such as a meter for detecting steps, counting steps and recording associated times. These measured values can be transmitted, for example, via a wired connection or a radio connection to another device, such as a mobile terminal, on which the received data are evaluated. For this purpose, for example, an application can be installed on the mobile terminal, which automatically provides an evaluation as a measurement result after receiving the measurement data. The measurement result, d. H. the determined locomotion of a person, for example, can be categorized, for example on the basis of an evaluation scale. This result can then be represented by a number within a scale or graphically on the mobile terminal. Furthermore, with the aid of the application on the terminal, a further device can be supplied with the measurement data and / or with the measurement result, for example a medical device which forwards the data centrally to a data store or which processes the data locally, for example in a patient file to save with further information about the subject. Furthermore, according to one exemplary embodiment, the device according to the invention can be configured such that raw acceleration data acquired by the device, which for example can only receive a time stamp, are transmitted by the device directly or indirectly via a further device to a central server, which then evaluates further measurement results.

In order to personalize the measurement data, it can be provided according to an exemplary embodiment of the device according to the invention that the device has or provides an identification which is stored together with the measurement data. Such an identification may be, for example, an identification number of the device according to the invention or an indication added by the test person, such as a name or a number.

Also, the identification of an application of the mobile terminal can be provided.

The measurement can be carried out semiautomatically by pressing a test person who carries the device according to the invention, for example as a measuring belt, a start button as soon as the beginning of the test track is passed. Furthermore, a stop button on the device can be pressed as soon as an end of the test track is passed. Between the start signal of the start button and the stop signal of the stop button, which can also be performed identically as a button, then runs automatically from a measurement. For example, in this simple embodiment, the test track start and the test track end may be a simple mark (eg, on the floor). This embodiment can be further improved by a fully automatic measurement provided. In this case, the start and stop signal of the measurement is automatically generated at the beginning of the test route or at the end of the test track, without the need for manual operation.

For recognizing the test track, in particular the test track beginning and the test track end, according to one embodiment, the device according to the invention can autonomously perform a measurement, for example using an RFID technology (RFID = Radio Frequency Identification, ie high-frequency identification). Here, the test track at their beginning and their end each with an active, d. H. equipped with an energy source, RFID chip are equipped. A transponder corresponding to the RFID chip, which is designed as a passive component and does not require a power supply, can detect the location of the RFID chip on the basis of a measured field strength or on the basis of an induced voltage in a coil of the transponder and from this the test route beginning and the test route end determine. Another alternative to defining the test track can be done with light barriers, in each case a light barrier at the beginning of the test track and a light barrier can be installed at the test track end. When passing the light barriers, in each case a signal, in particular a trigger signal, can be provided in order to start or stop the measurement for determining the locomotion of a person. In this case, it can be provided, for example, that the light barriers are installed in two pairs of barks, with two barks at the beginning of the test track and two barks at the end of the test track, which thus serve as delimiting elements for defining the beginning of the test route and the end of the test track by optical means for providing the two light barriers. In this case, the barges can form a mobile measuring laboratory, wherein the device according to the invention is used within the mobile measuring laboratory. In this case, the established barks can be part of a measurement evaluation device and a mobile measurement device part of a measured value acquisition. Thus, in one exemplary embodiment, a measuring belt can collect acceleration measurement data with the aid of at least one acceleration sensor and send it via a radio link to a measured value evaluation in one or more barks. In this case, an evaluation unit can be installed in the bark itself. Furthermore, it is also possible for the evaluation of the measurement data to take place by storing a mobile terminal in the bark, which provides the radio link for the bark and evaluates measured values with the aid of an installed application, which are then forwarded, if necessary, to a central database within the hospital or the internet.

The test track can be provided, for example, in a hallway of a building, as it occurs in hospitals. In general, the length of the test track should be short so that the measuring system can be used at all in a hospital or doctor's office. Furthermore, the measurement result can be falsified if the test subject fatigues within the test track and the nature of the steps changes. A preferred length of the test track is in the range of 5 to 15 meters. It can also be provided in an alternative embodiment that the test track is installed on an inclined plane, for example a ramp with a constant angle of inclination. In this case, a fatigue phenomenon caused by the slope while walking can be specifically caused and compared, for example, with a measurement on a straight line.

The measuring laboratory can be designed as a mobile gait lab, for example, by limiting elements to define the beginning of the test route and the test track end for measurements are installed and then removed again. The mobile measuring laboratory can then be designed as a measuring kit or measuring cuboid in the transport state by stowing the limiting elements with each other so that they can be transported together, for example, on a carrying belt. Further accessories of the measuring laboratory, such as a supply line for power supply, a measuring device for the test person or a measuring belt can be accommodated in a cavity of the limiting elements, so that the measuring laboratory can be transported compactly and can then be rebuilt as needed.

According to one embodiment, the limiting elements are designed as barks, which can also be supplied with electrical energy in order to emit signals or to operate a light barrier. In this case, limiting elements can be connected to the general power supply or operated with a separate energy source, such as an accumulator. Furthermore, one or more limiting elements can be used to store a mobile terminal, for example a smartphone, at the beginning or at the end of the test track. The mobile terminal can then give instructions about speech or graphics to prepare a measurement and provide measurement results. For example, the test person is informed in preparation for the measurement that the measurement can be started. Furthermore, the test person can be informed about the length of the installed test track and how many meters are still covered within the test track during the measurement. Furthermore, an interaction can also take place with the mobile terminal in that the test person or operator indicates which ones other parameters to be taken into account during the measurement, such as date and time, a previous medication, a name of the subject, etc. On the mobile device, a corresponding application is started before the measurement.

Further preferred embodiments of the invention are disclosed in the dependent claims.

The invention, as well as other features, objects, advantages and applications thereof, will be explained in more detail below with reference to a description of preferred embodiments with reference to the accompanying drawings. In the drawings, the same or similar reference numerals designate the same or corresponding elements. All described and / or illustrated features alone or in any meaningful combination form the subject matter of the present invention, regardless of their combination in the claims or their dependency.

In the drawings shows a schematic representation

1 a measuring belt according to an embodiment of the present invention;

2 a partial view of the measuring belt according to 1 in the area of the belt buckle;

3 a block diagram of the belt buckle in the 1 and 2 integrated device according to the invention for determining the locomotion of a person;

4 a schematic representation of an embodiment of a measuring arrangement for defining a test track;

5 a schematic diagram with a waveform of the field strength intensities of the test track of 4 ;

6 an exemplary schematic diagram with location of a measurement window and within half of the measurement window detected steps of a subject along the test track;

7 a highly schematic principle diagram for explaining a test track according to an embodiment of the present invention; and

8th an exemplary measurement diagram of the method according to the invention with acceleration measured values during a walking phase of a subject.

1 shows a measuring belt 1 in a plan view for determining a movement of a person according to an embodiment of the present invention. The measuring belt 1 can be attached to the body of a subject, with the measuring belt 1 is intended to be arranged around the waist of the subject. The measuring belt 1 has a belt buckle 2 on that on a belt band 3 is attached. Near the belt buckle 2 with a measuring and evaluation device incorporated therein 10 that in the 2 and 3 is described on the belt band 3 a belt area exists in which a receiving arrangement 4 or a case for receiving a mobile terminal 5 is arranged. A velcro closure 6 between the belt buckle 2 and the recording arrangement 4 serves to guide or hold an electrical connection cable 7 , When using a cable connection 7 to the terminal 5 There is the advantage that over the cable connection 7 the measuring and evaluation device 10 with energy for operating the measuring and evaluation device 10 can be supplied. This can be done, for example, via a USB cable with corresponding interfaces on the mobile terminal 5 and the belt buckle 2 happen.

Alternative to the connection cable 7 in 1 can also be another radio interface between the measuring and evaluation 10 in the belt buckle 2 and the mobile terminal 5 be provided, for example, a standardized NFC connection (NFC = Near Field Communication) with appropriate interfaces to the mobile terminal 5 and the measuring and evaluation device 10 , Such a connection can provide a transmission distance of a few centimeters and is therefore suitable for the distance between the belt buckle 2 and the recording arrangement 4 with the mobile terminal arranged therein 5 to overcome. Furthermore, energy can also be transmitted via induction, so that the measuring and evaluation device 10 no own power supply needed.

The mobile device 5 in 1 is for example a mobile phone or a smartphone that has a radio connection 8th with a peripheral device 9 how a server or the internet can establish a communication connection. The radio connection 8th can be a cellular connection that supports one or more technologies such as LTE or higher LTE generations. Also, the radio connection 8th a near field communication link, which over a few meters a communication link to a processing unit 9 as a peripheral device, such as Bluetooth technology.

Furthermore, it is possible that the mobile terminal 5 via a corresponding radio link with the measuring and evaluation device 10 is in communication connection while the mobile terminal 5 not on the belt band 3 is fastened but carried by the subject in a different way during the measurement, for example by storage in a trouser pocket. Furthermore, the mobile terminal 5 Also be far away from the subject and yet in communication with the measurement and evaluation device 10 be, for example, by storage in a bark of the measuring and evaluation device 10 , Regardless of the storage location of the mobile device 5 during the measurement, a program element or, for example, an application in the mobile terminal 5 be present, which accompanies the preparation and the measurement by voice, for example by announcing when the measurement can be started or by explaining in which direction the subject should go through the test track. Furthermore, a voice control can also be provided, so that the test person or another person performs the measurement by voice commands.

Furthermore, it is based on the embodiment of the 1 possible, the mobile device 5 as a data glasses, so that no attachment of a mobile terminal 5 on the belt band 3 necessary is. A data goggles can be worn by the subject during a measurement and can with the measuring and evaluation device 10 in the belt buckle 2 communicate via a radio link. In addition, has data glasses as a mobile device 5 the advantage that information in the field of view of the subject can be projected, such as the distance still to be reached until reaching the end of a test track or instructions for performing the measurement, as the direction of travel through the test track.

2 shows a partial view of the measuring belt 1 according to 1 in the area of the belt buckle 2 in which the measuring and evaluation device 10 integrated according to an embodiment of the invention. The measuring and evaluation device 10 is in 2 schematically as an integrated box within the belt buckle 2 shown. At the box 14 opposite end of the belt buckle 2 is a thorn 11 provided at which the free end of the measuring belt 3 by means of an opening provided there 12 for receiving the thorn 11 and to close the belt band 3 is hooked.

3 shows an exemplary block diagram of the measuring and evaluation device 10 as an electronic circuit, in the belt buckle 2 of the 1 and 2 is integrated. The measuring and evaluation device 10 is used to determine the movement of a person. The measuring and evaluation device 10 has a microprocessor 13 in the form of a microprocessor 13 on, whose processor clock frequency of a quartz crystal 14 is generated. The microprocessor 13 has a memory and is equipped with a three-dimensionally operating 3D acceleration sensor 15 electrically connected. The 3D acceleration sensor 15 is formed in one unit, but in an alternative embodiment may be composed of three individual acceleration sensors, each of the acceleration sensors covering one of the three spatial directions. Further, the microprocessor 13 electrically with a tilt sensor 16 , an analog-to-digital converter 17 and a transponder 18 electrically connected. In addition, the measuring and evaluation device has 10 an interface 19 to be able to forward the measurement data obtained to other devices, such as the mobile terminal 5 , Furthermore, the interface 19 Be formed bi-directionally, so that also data or information from the outside via the interface 19 to the measuring and evaluation device 10 can reach, for example, from the mobile terminal 5 ,

In the embodiment of the measuring and evaluation device 10 of the 3 acceleration forces are used to detect a person's steps. The detected steps are counted and each detected step is assigned to a point in time. The transponder 18 is used on the one hand to determine a start time and a stop time of the measurement and to allow identification of the person or the measuring belt. The microprocessor 13 Captures and processes the data from the 3D accelerometer 15 measured on the body of the person acceleration forces in all three dimensions of space. This is done by the tilt sensor 16 This is due to the fact that the component of the acceleration is taken into account in the measurement, which proceeds in the direction of gravity, from the three-dimensional acceleration forces. This direction of acceleration is used for recognizing a step, since an impact of a foot of the person on a ground means a strong acceleration. In this way, steps are recognized, even if the belt buckle 2 is not exactly aligned. However, the belt buckle sits 2 so on the body of the person that the acceleration of the feet or the impact of a foot on a surface up in the belt buckle 2 is clearly measurable. The analog of the 3D accelerometer 15 detected acceleration measurements are via an analog-to-digital converter circuit, for example integrated in the acceleration sensor 15 digitized and as digital measurement data to the microprocessor 13 directed. Further, the microprocessor indicates 13 a memory area in which an implemented program of the microprocessor 13 is present, that the Measured value acquisition and the evaluation of the measured data in the microprocessor 13 controls and for their transmission via the interface 19 to the mobile device 5 provides. Furthermore, in the belt buckle 2 an energy source may be integrated, for example a battery or a rechargeable battery, if not otherwise, such as via a USB interface or via an NFC interface from the mobile terminal 5 or another device energy for electrical power supply of the measuring and evaluation device 10 is transmitted.

4 shows a schematic representation of an embodiment of an arrangement for defining a test environment 20 or to provide a measuring laboratory 20 with a test track 21 the length d with a test patch start 22 and a test track end 23 , The test track beginning 22 comes with a first delimiter 24 and the test track end 23 with a second limiting element 25 established. The boundary elements 24 . 25 For example, they are designed as flat elements and in a corridor of a hospital on a wall 26 attached, for example, on a handrail. Alternatively, the boundary elements 24 . 25 be designed as barks or cones, the arbitrary on a wall 26 , a floor 27 or another device of a test environment 20 can be installed. The boundary elements 24 . 25 each have a device 28 . 29 to allow automated detection of a start time and a stop time. The start time is recorded as soon as a person 30 with a measuring belt attached 1 the test track beginning 22 passes. The stop time is recorded as soon as the person 30 the test track end 23 passes. This results in striking points or areas A, B, C, D and E, the test track 21 characterize. In area A there is still no time and / or step measurement, since this is the area before entering the test track 21 is. At point B, through the test track beginning 22 is set, the measurement is started to determine the locomotion of the person 30 started. Area C lies within the test track 21 , The point D is from the test track end 23 fixed, the measurement is terminated on it. The area E lies behind the test track 21 in which no time and / or step measurement takes place. The direction of going through the test track 21 can be arbitrary, so that the points B and D and the areas A and E can be reversed. This is possible, for example, if the limiting element 24 . 25 are formed identically with regard to their electronic signaling and both a test track beginning 22 and a test track end 23 can define.

In the present embodiment of 4 are the facilities 28 . 29 the boundary elements 24 . 25 as RFID devices, in particular as an active RFID part with a power supply and a transmitting and receiving device formed with the transponder 18 as a passive RFID part, which does not need a power supply, cooperate. The distance d, ie the length of the test track 21 , between the two boundary elements 24 . 25 with the respective RFID devices 28 . 29 For reasons of higher measurement accuracy or significance, it is preferably chosen such that the length d is significantly greater than an average step length s of the candidate person in question 30 is, and thus with the measurement and evaluation device according to the invention 10 the counting of several steps is possible. As a guide for the subject 30 are parallel to the wall 26 and close to the ground 27 one of consecutive marks 31 attached, thus visually the course of the defined test track 21 features. Runs the person 30 with the measuring belt 1 along the test track 21 in the arrow direction of the markings 31 , so are RFID signals of the delimiting elements 24 . 25 from the transponder 18 in the measurement belt 1 receive.

5 shows a schematic diagram with a waveform 40 the field strength intensities of the two RFID devices of the test environment 20 from 4 in which the intensity of the electromagnetic field strength is plotted on the y-axis and the x-axis represents the time.

Here is in 5 shown as an example, as the transponder 18 (or the respective boundary elements 24 . 25 ) in the measuring and evaluation device 10 of the 3 detected a waveform of the field strength. From the two RFID devices 28 . 29 with the respective limiting elements 24 . 25 In each case an electromagnetic field is emitted and as an overlay of the transponder 18 receive. 5 shows the field strength history when the person 30 with attached measuring belt 1 with measuring and evaluation device incorporated therein 10 along the markings 53 the test track 21 running. Approaching the person 30 the first limiting element 24 with integrated RFID device 28 , so decreases with decreasing distance to the first limiting element 24 at a position A, the field strength and thus the signal intensity to, from the transponder 18 (or from the first boundary element 24 ) is detected. A first maximum of the transponder 18 detected signal intensity arises when the person 30 at a time t _B at the shortest distance to the first limiting element 24 passes this at the position B. Does the person move? 30 continue in the direction of the second limiting element 25 with integrated RFID device 29 , at an intermediate position C, the detected signal intensity decreases to a minimum and then increases with constantly decreasing Distance to the second boundary element 25 continuously, until at the shortest distance to the second limiting element 25 a maximum of the detected signal intensity at the position D at a time t _D with t _D > t _{C is} reached, which in this case predominantly of the electromagnetic field of the second limiting element 25 is caused. With increasing distance to the second limiting element 25 the measured field strength sounds in the transponder 18 (or in the second boundary element 25 ) continues until the field strength in a position E has reached its minimum value.

In other words, it results in a non-constant field strength profile, that of the position of the measuring belt 1 in terms of the two limiting element 24 . 25 is dependent. Maximum field strength values 41 . 42 occur each time when the person 30 with the measuring belt 1 at point B and at point D the 4 located. In front of the test track 21 in area A, within the test track 21 in area C and behind the test track 21 in the area E the field strength values are lower or zero. The waveform 40 is in the measuring belt 1 over the transponder 18 captured with the microprocessor 13 further processed. With the Mikroprozezzor 13 become the maximum values 41 . 42 the waveform 40 Times t _B and t _start and t _D or t _stop assigned. At the time t _start which corresponds to the time t _B , a time measurement is started and at the time t _stop , which corresponds to the time t _D , the time measurement is stopped. In this case, counters or even a stopwatch functionality (for example, a smartphone) can be used. Alternatively, other possibilities, such. B. absolute time measurements and subsequent difference formation (s). In this way it can be determined, in which time the person the test track 21 has passed through the length d. In addition, the number of steps the person 30 with the help of the acceleration sensor 15 and the microprocessor 13 determined. The steps will be within the test track 21 counted so that t _start clears the step count and t _{stop completes} the step count. It therefore becomes a measurement window 50 , as in 6 shown, predetermined, in which the detected steps are counted.

6 shows an exemplary schematic diagram with a measurement window 50 , where on the x-axis of 6 the time and on the y-axis the number of steps or the event of a step at a certain time is plotted. The measurement window 50 exemplifies a time interval and begins at time t _start , which is the time t _B in 5 corresponds and ends at time t _stop , which is the time t _C in 5 equivalent. Within the measurement window 50 become detected steps of the person 30 along the test track 21 counted. This happens at the times t ₁ to t _{N + 1} , where N is the number of detected steps within the test track 21 is. With the measuring and evaluation device 10 as they are in 3 is shown, each detected step is assigned to a time. This happens within the time interval {t ₁ , t _{N + 1} } with the acceleration sensor 15 the circuit 10 using the detected steps of the person 30 by at any time within the time interval that of the microprocessor 13 continuously recorded acceleration measured values of the 3D acceleration sensor 15 be evaluated in real time.

An embodiment of the measuring principle according to the invention is based on 7 explained. In 7 is a test track 21 the length d given with a test track beginning 22 and a test end 23 , The determination of a locomotion of the person 30 is performed by a mean speed of movement of the person 30 within the test track 21 is detected. This happens, for example, with a measuring belt 1 as he is in 1 is shown. This is done with the transponder 18 of the measuring belt 1 the field strength along the test track 21 determined, so that at the maximum values of the field strength, a start time t _start and a stop time t _stop results, as exemplified in the 5 and 6 shown.

According to one embodiment, the passive RFID transponder takes 18 the measuring and evaluation device 10 if he's close enough to any of the RFID facilities 28 . 29 comes, as in 4 represented by a coil of the circuit 10 , as in 3 shown, energy from the radiated electromagnetic field on to the transponder 18 coupled microprocessor 8th to supply, without this would require its own power supply in the form of a battery. The measuring and evaluation device 10 at the time t _start, that upon reaching the shortest distance to the first limiting element 24 activated at the position B in accordance with a program then starting by a to the transponder 18 belonging internal capacitor charges, whereby the connected microchip or microprocessor 13 use this charge for its energy supply. This is the microprocessor 13 being able to start its program, wherein a time counter implemented in the program starts with setting the time t _start as the start value. This timer runs after its initialization until the person 30 with the applied measuring belt 1 and the measuring and evaluation device accommodated therein 10 in the influence of the electromagnetic field of the second limiting element 25 device and the microprocessor 13 at the position D upon detection of the highest field strength, the time _counter stops at the time t _stop . As long as the time counter remains activated in the time interval {t _start , t _stop }, the microprocessor 13 that of the accelerometer 15 measured values recorded in this measurement window {t _start , t _stop } are stored continuously and saved. By stopping the timer at time t _{N + 1} , the microprocessor closes 13 also the measurement window 50 , thus terminates the measuring procedure or the current measurements and then evaluates the recorded and stored measured values. Instead of a time counter, other means capable of storing times t ₁ to t _{N + 1} together with the event of a detected step may be used.

Furthermore, the test distance d is known. This happens, for example, by prior measurement of the distance d between the first limiting element 24 and the second limiting element 25 , The distance measurement is done for example by positioning the two boundary elements 24 . 25 at predetermined positions or by manually measuring the test line distance d. In an alternative embodiment, a predetermined distance d can be achieved by a common element, for example a band, on the two fastening elements 24 . 25 be specified. When installing the two boundary elements 24 . 25 The band is designed so that there is a straight connection between the two boundary elements 24 . 25 has and thus determines the distance d. In an advantageous embodiment, the measurement of the test track distance or test track length can be carried out automatically. For this purpose, the boundary elements 24 . 25 be configured accordingly, for example, with infrared sensors that can determine a distance due to reflections or transit time measurements.

From the distance d and the determined time 60 (in the schematic representation of 7 illustrated by a stopwatch) between t _start and t _stop can be an average speed of movement of the person 30 to be obtained. Further steps become 61 (in the schematic representation of 7 illustrated by a notepad with a stroke count) of the person 30 within the test track 21 detected. This happens, for example, with the acceleration sensor 15 of the measuring belt 1 of the 1 - 3 , Finally, the average stride length of the person 30 from the average speed of movement and a number of steps 61 within the test track 21 determined. This happens in the microprocessor 13 of the measuring belt 1 , To improve the measurement accuracy, the length of a first step of the person 30 into the test track 21 in and the length of a final step of the person 30 from the test track 21 out of consideration in determining the average stride length. This means that only whole steps within the range 62 be counted, sub-steps in the areas 63 . 64 stay unconsidered.

Furthermore, in 7 in detecting steps of the person 30 within the test track 21 also records each point in time of a step, so that when steps are detected, the corresponding points in time of the steps can be assigned. In this case, it is advantageously provided that a step is only detected as such if a predetermined period of time has elapsed after the immediately preceding step. This avoids that further acceleration signals are assigned to a step, although these acceleration signals belong to the already detected step. It may happen that, depending on the rolling of the foot on the floor several abrupt movements take place, so that a plurality of acceleration signals are recorded for the same step. Usually, the heel of a foot signals the impact of the foot on the floor, so that a relevant acceleration signal is measured at this impact of the heel. The corresponding signal can also be called an "heel strike" signal.

Overall, the average stride length can be calculated from the mean travel speed and the length of the trail in the area 62 be determined between the first and last recorded within the test route occurrence of the person. This means that in 7 the first step at t ₁ and the last step at t _{N + 1} and all steps in between are taken into account in the measurement. This results in a considered test track length in the range 62 from (d - v (t ₁ - t _start + t _stop - _{N + 1} )), where the ranges 63 . 64 disregarded by sub-steps. This results in the average step length s of the person 30 calculated as follows: s = (d -v (t ₁ -t _start + t _{stop -N + 1} )) / N, where v is the average speed, N is the number of complete steps of the person within the test track 21 , t _start the start time, t _stop the stop time, t ₁ the time of the first within the test track 21 detected occurrence, t _{N + 1,} the time of the last within the test track 21 recorded occurrence and d the length of the test track 21 is. The median stride is an indicator of how the person is 30 within the test track 21 moves.

8th shows an exemplary measurement diagram 70 of the method according to the invention with acceleration measurements during a walking phase of a person, wherein the y-axis represents the acceleration in units of the gravitational acceleration and the x-axis represents the time axis in units of seconds. In the measurement diagram 70 are the measured acceleration values of the person 30 along the measuring section 21 applied. A first measurement curve K1 shows the acceleration values detected in forward / backward direction. A second Measurement curve K2 shows the acceleration values detected in the vertical direction. A third measurement curve K3 shows the acceleration values detected in the lateral direction. In a fourth curve K4 is a preset threshold. It can be seen clearly that the curve K2 cuts the threshold curve K4 down several times, which indicates an occurrence of the test person. Threshold curve K4 is not a horizontal straight line, as the current threshold may incorporate certain stepping enhancement parameters, such as: B. Measured values of the curves K1 and K3. Vertical error bars indicate the actual detections of an occurrence. Shortly after cutting the curves K2 and K4, a step detection takes place.

Overall, with the present invention and its developments, the determination of an average step length can be carried out indirectly via the measurement of an average travel speed and the detection of steps. In this case, a step detection is preferably carried out with the aid of one or more acceleration sensors. An optional tilt sensor can be used to better correlate the direction of acceleration with respect to the direction of gravity. The accuracy of the location information determined by an amplitude analysis when using an RFID technology and the associated time recording is sufficient for the determination of an accurate speed, and in particular so accurate that an average step length can be determined. When using an RFID technology, in addition to a measurement of a signal field strength, an identification of the subject or the measuring device used can be made available. The invention makes it possible to provide a cost-effective measurement at any location in order to determine a movement of a person. The measuring device can also be operated by the person alone, without doctors or other auxiliary personnel are required.

Use cases of the present invention can be designed as follows:

- Clinical rapid tests - clinical routine or in clinical trials:

The patient or the test person receives a measuring belt and goes up and down several times on two barks erected as limiting elements of the test track in the corridor of a clinic. The values for walking speed and stride length are routed via a mobile terminal present in the vicinity of the test track with the aid of a Bluetooth interface to a central server and are available there for integration into the patient record.

- Surveillance in a nursing home (analogous to home monitoring in clinical trials):

Endangered residents living with a measuring belt 1 , such as in 1 are equipped, go more often a day at a equipped with RFID or photocells bark fixed route in the apartment or in the house over. The speed and step length measurements are sent along with timestamps via a short-range radio link to a central database. There, algorithms compare the current measurements with the usual patterns and inform the nursing staff about abnormalities via evidence-based decision support algorithms (eg no signal on the way bedroom kitchen before 10:00 h, otherwise the home residents always at latest 9:30 h in the kitchen is on). Bidirectional audio and video communications allow call center personnel to distinguish real alarms from false alarms.

- Use in epidemiological studies

For example, the invention may be used in research projects coupled with blood transfusion services. The mobile measuring electronics are brought to the recruiting station. Blood donors / patients can carry out the measurement on-site without great expenditure of time and space.

- Assistance in checking the effect size and sustainability in therapeutic interventions and rehabilitation measures:

The success of fitness and exercise programs can be checked objectively and automatically via the measurement and, if necessary, documented with payers.

- Use in telemedicine

Since exemplary embodiments of the method according to the invention and the device according to the invention can proceed fully automatically, use in telemedicine can be advantageous.

The invention has been explained in more detail above with reference to preferred embodiments thereof. However, it will be apparent to those skilled in the art that various modifications and changes can be made without departing from the spirit of the invention.

LIST OF REFERENCE NUMBERS

1

measuring belt

2

belt buckle

3

girdle

4

up assembly

5

mobile terminal

6

velcro fastener

7

connecting cable

8th

radio link

9

peripheral device

10

Measuring and evaluation device

11

mandrel

12

opening

13

microprocessor

14

quartz crystal

15

3D acceleration sensor

16

tilt sensor

17

Analog to digital converter

18

transponder

19

interface

20

test environment

21

test track

22

Test Plug beginning

23

Test track end

24

first limiting element

25

second boundary element

26

wall

27

floor

28

Facility

29

Facility

30

person

31

mark

40

waveform

41

maximum field strength value

42

maximum field strength values

50

measurement window

60

Time

61

steps

62

Area

63

Area

64

Area

70

measurement chart

K1

first trace

K2

second trace

K3

third trace

K4

Curve

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 5952585 [0004]
• DE 69628407 T2 [0006]
• DE 102005019924 A1 [0007]

Claims (17)

Method for determining a movement of a person ( 30 ) by means of a test track ( 21 ) with a test route beginning ( 22 ) and a test track end ( 23 ) comprising: - detecting a mean speed of movement of the person ( 30 ) within the test track ( 21 ); - Recording steps ( 61 ) the person ( 30 ) within the test track ( 21 ); and determining an average step length of the person ( 30 ) from the mean travel speed and from the recorded number of steps ( 61 ) within the test track ( 21 ). Method according to claim 1, characterized in that the length of a first substep of the person ( 30 ) into the test track ( 21 ) and the length of a final partial step of the person ( 30 ) from the test track ( 21 ) is disregarded in determining the average stride length. Method according to claim 1 or claim 2, characterized by - detecting a start time when the person ( 30 ) the test track beginning ( 22 ) happens; Detecting a stop time when the person ( 30 ) the test track end ( 23 ) happens; wherein the detection of the average speed of movement of the person ( 30 ) within the test track ( 21 ) by calculating from the start time, the stop time and the length of the test track ( 21 ) he follows. Method according to one or more of Claims 1 to 3, characterized in that the steps are carried out by at least one person ( 30 ) mounted acceleration sensor ( 15 ). A method according to claim 4, characterized in that for detecting the steps by the at least one acceleration sensor ( 15 ) an appearance of the person ( 30 ) on the test track ( 21 ) is detected. Method according to one or more of claims 1 to 5, characterized in that in detecting steps of the person ( 30 ) within the test track ( 21 ) the corresponding times of the steps are recorded. A method according to claim 6, characterized in that a step is only detected as such, if after the immediately preceding step detected a predetermined period of time has passed. Method according to one or more of Claims 1 to 7, characterized in that the average step length is determined from the average speed of travel and the length of the route between the first and last occurrences of the person detected within the test track ( 30 ) is determined. Method according to one or more of claims 1 to 8, characterized in that the mean step length s is determined according to the following formula: s = (d - v (t ₁ - t _start + t _stop - _{N + 1} )) / N where v is the average speed, N is the number of complete steps of the person ( 30 ) within the test track ( 21 ), t _start the start time, t _stop the stop time, t ₁ the time of the first within the test track ( 21 ) detected occurrence, t _{N + 1 is} the time of the last within the test track ( 21 detected occurrence, and where d is the length of the test track ( 21 ). Contraption ( 1 ) for determining a locomotion of a person ( 30 ) by means of a test track ( 21 ) with a test route beginning ( 22 ) and a test track end ( 23 ), comprising: - means ( 10 ) for detecting a mean speed of movement of the person ( 30 ) within the test track ( 21 ); - Medium ( 10 ) for detecting steps of the person ( 30 ) within the test track ( 21 ); and - means ( 10 ) for determining an average step length of the person ( 30 ) from the mean travel speed and from the recorded number of steps within the test track ( 21 ). Apparatus according to claim 10, characterized in that the length of a first substep of the person ( 30 ) into the test track ( 21 ) and the length of a final partial step of the person ( 30 ) from the test track ( 21 ) is disregarded in determining the average stride length. Device according to claim 10 or claim 11, characterized by - means ( 10 ) for detecting a start time when the person ( 30 ) the test track beginning ( 22 ) happens; - Medium ( 10 ) for detecting a stop time when the person ( 30 ) the test track end ( 23 ) happens; wherein for detecting the average speed of movement of the person ( 30 ) within the test track ( 21 ) Medium ( 10 ) for calculating the average travel speed from the start time, the stop time and the length of the test track ( 21 ) are provided. Device according to one or more of claims 10 to 12, characterized in that the means ( 10 ) for detecting steps at least one on the person ( 30 ) mounted acceleration sensor ( 15 ) exhibit. Apparatus according to claim 13, characterized in that the at least one acceleration sensor ( 15 ) an appearance of the person ( 30 ) on the test track ( 21 ) detected. Device according to one or more of claims 10 to 14, characterized by means ( 10 ) for detecting the times of the steps in detecting steps of the person ( 30 ) within the test track ( 21 ). Device according to one or more of claims 10 to 15, characterized in that means ( 10 ) for determining an average step length thereof from the mean travel speed and the length of the route between the first and the last within the test track ( 21 ) recorded occurrence of the person ( 30 ). Device according to one or more of claims 10 to 16, characterized in that means ( 10 ) for determining an average step length of the person ( 30 ) calculate the mean step length s according to the following formula: s = (d - v (t ₁ - t _start + t _stop - _{N + 1} )) / N where v is the average speed, N is the number of complete steps of the person ( 30 ) within the test track ( 21 ), _tstart the start time, t _stop the stop time, t ₁ the time of the first within the test track ( 21 ) detected occurrence, t _{N + 1 is} the time of the last within the test track ( 21 detected occurrence, and where d is the length of the test track ( 21 ).

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