WO2007137851A2

WO2007137851A2 - Sensor device and method for generating and visualising signals indicating the motor activity of a person walking

Info

Publication number: WO2007137851A2
Application number: PCT/EP2007/004837
Authority: WO
Inventors: Peter Lenhart
Original assignee: Peter Lenhart
Priority date: 2006-05-31
Filing date: 2007-05-31
Publication date: 2007-12-06
Also published as: WO2007137851A3; DE102006025447A1

Abstract

The invention relates to a sensor device and a method for generating signals indicating the motor activity and the motor co-ordination of the musculature of a person walking. The invention especially relates to the problems relating to the generation of signals for the analysis and evaluation of the walking kinematics of a person from a sports medicine, ergonomic or therapeutic point of view. The aim of the invention is to provide solutions which enable the kinematics of a person to be described and evaluated in a highly informative manner. To this end, a sensor structure is used to generate signals indicating the kinematics of a person, said sensor structure comprising a plurality of sensor devices which are used as such to supply signals indicating the local pressure or force exerted by a foot at a plurality of measuring points over a surface to which a foot is applied. In this way, information about the temporal variations of the foot surface pressure distribution can be recorded advantageously in real time as a person is moving along.

Description

Sensor device and method for generating and visualizing the running motor of a person indicative signals

The invention relates to a sensor device and a method for generating with regard to the running kinematics and the motor coordination of the running muscles of a person indicative signals.

The invention is concerned in particular with the problem of providing signals for analyzing and evaluating the running kinematics of a person under sports medicine, work ergonomic or therapeutic aspects.

The invention has for its object to provide solutions by which it is possible to describe the running kinematics of a person with high informative value and evaluate.

This object is achieved according to the invention by a sensor structure for generation with regard to the kinematics of a person indicative signals, wherein the sensor structure comprises a plurality of sensor devices are provided as such intended to provide indicative signals at several measuring points within a FußaufStandsfläche with respect to the local contact pressure or the local Aufstandskraft a foot ,

This advantageously makes it possible to record in real time during walking or walking a person information about the time course of the Fußflächenpressungsverteilung. On the basis of the signals obtained in this way, in particular the running characteristic and thereby also the instantaneous degree of fatigue of the user can be assessed. Based on this information, it is possible to analyze and optimize a running training of a user. Based on the history of the information thus obtained, a training state of the user can be determined.

On the basis of the signals obtained according to the invention, it is also possible to give the user real-time feedback about the instantaneous footprint pressure distribution. On the basis of this information, it can also be determined in particular how far the user currently carries out an optimal foot load. With this information, the user can perform a power scheduling for a still-to-be-processed race, e.g. make long distance runs.

The sensor device according to the invention can also be integrated into a step observation instrument or system which, as such, acts as a pedometer, whereby not only the number of steps with high reliability is determined, but also the characteristic of the steps can be assessed. In particular, a distinction can be made between walking and running and the dynamics of the respective steps can be evaluated. On the basis of the sensor signals obtained according to the invention, it is also possible to determine the suspension time of the user between the placement of the two feet.

According to a particularly preferred embodiment of the invention, the sensor structure comprises a first sensor which serves to detect the contact pressure in the heel area. The sensor signal collected by this sensor preferably serves as a reference signal for the further measurement signals collected for the respective step cycle. The sensor structure according to the invention preferably comprises at least one further sensor which serves to detect the contact pressure in the front area of the ball, in particular in the zones explained in greater detail below in conjunction with the figures.

It is possible to provide further sensors, in particular toe-pressure sensors, which make it possible to detect the contact pressure in the region of the contact surfaces of the toe.

According to a particularly preferred embodiment of the invention, the sensors are designed as pressure sensors. For this purpose, these sensors may comprise a flexible layer, for example of an electrically conductive foam material, the conductivity of which being changed by appropriate pressure on this flexible layer. This change in conductivity can be used as a measurement signal for calculating the compression pressure.

It is also possible to design the pressure sensors in such a way that the local pressure is detected on the basis of the capacitance change of a capacitor structure. This capacitor structure can be formed, for example, by two electrically conductive layers which are separated from one another by a compressible layer, in particular a foam material which acts as a dielectric. By appropriate compression of the Schaumstoffläge results in a change in the capacitance of the capacitor system thus formed. This change in capacity can be used as the signal-technical basis for determining the contact pressure. It is also possible to accomplish the pressure measurement through small pockets which are filled with a viscous medium, in which medium small pressure sensors, eg in piezo construction are embedded. It is also possible to form the sensors by a plurality of, for example, electrically or optically conductive layers, wherein the measuring arrangement is accomplished such that a signal indicative of the contact pressure is generated on the basis of a physical effect, which as such correlates with a compression of those layers.

The sensor structure according to the invention is incorporated in a shoe insert according to a particular aspect of the present invention. This shoe insert is preferably designed such that it forms a hermetically inherently self-contained structure, so that the pressure-measuring properties are not changed by influences beyond the pure load of the shoe insert, in particular under the action of moisture.

It is also possible to incorporate the sensor structure according to the invention directly into a shoe. In this case, in particular in the area of the shoe heel and the shoe sole, relatively large space sections are available for the arrangement of the sensor device and for the realization of corresponding conductor tracks and circuits. It is also possible to incorporate the sensor device into a stocking which is attracted by the user. This makes it possible to determine the running behavior of the user without shoe, or in a shoe. This makes it possible in particular to evaluate the quality of shoes.

It is also possible to realize the sensor device by means of a plurality of flat sensor elements that can be placed on the foot, in particular attachable to the foot.

According to a particularly preferred embodiment of the invention, a signal pre-processing circuit is provided which serves as such, a pre-evaluation and preferably Normalization of the pressure measuring signals generated via the respective sensor devices make. This signal preprocessing circuit is preferably designed such that it converts the pressure measuring signals into digital signals. The signal preprocessing circuit may be provided with an electronic storage device in which the currently determined measurement signals are stored. These signals are preferably addressed at a relatively high reading speed, eg, readable for the respective zones to be examined.

According to a particularly preferred embodiment of the invention, the signals indicative of the time course of the pressures in individual zones of FußaufStandsflächen be evaluated by an evaluation procedure. This evaluation procedure can be adapted to the respective analysis purpose. It is thus possible, in particular, to design the evaluation procedure in such a way that a standardization approach is enabled which, as such, enables an evaluation or comparison of temporally derived step cycles. On the basis of the detected and evaluated signals, it can be determined, for example, whether the kinematics of the particular user fulfills certain characteristics. It is also possible to provide feedback systems which, as such, allow the respective user to obtain information about the quality of the coordination or the activation of his running muscles directly while running. For example, the user can be notified acoustically if the sensor signals indicate that a certain degree of exhaustion has been reached. It is possible to use the recorded signals to document a training run and determine when certain changes in the running characteristics, in particular fatigue effects on the foot load occur. Preferably, evaluation results are generated for each step. This evaluator If necessary, results can be stored in compressed form for subsequent steps.

It is possible to compare the degree of correlation of the load pattern typical for the respective step with a reference pattern on the basis of the data relating to subsequent steps. For example, this reference pattern may be tuned to correspond to an average foot load pattern. The reference pattern may also be designed to represent an ideal foot load pattern.

These evaluations of the temporal characteristics of the foot load can be visualized using graphically designed user interfaces. These user interfaces can be designed in such a way that several evaluation criteria can be selected by a user based on this menu, so that the foot load measurement signals generated during a training run or an observation run can be evaluated and visualized according to various criteria.

Further details and features of the invention will become apparent from the following description taken in conjunction with the drawings. It shows:

FIG. 1 is a schematic diagram illustrating leg kinematics during a user's step;

FIG. 2 shows a sketch for illustrating a footrest surface which is subdivided into a plurality of pressure detection zones, FIG. 3 shows a schematic representation for explaining a sensor structure according to the invention which is realized as such in connection with a stocking,

FIG. 4 shows a simplified representation of a sensor structure according to the invention which is realized as such in interaction with a shoe insert,

FIGS. 5a, 5b are diagrams for illustrating the time profile of the pressure measurement signals collected during a step cycle;

Figure 6 is a diagram illustrating the change in the Fußabrollcharakteristik a user over a longer training run away.

In FIG. 1, the individual movement phases of the supporting leg during a step of a person are shown in a greatly simplified manner. During this step, first placing the foot on the ground on the heel area. After putting on the heel area, different zones of the ball area of the foot contact the ground with changing local surface pressure. Towards the end of FußaufStandsabschnittes there is a load on the toe area and then lifting the foot. Throughout the ground contact phase, the footing forces are introduced into the areas of the footrest area shown here as black areas.

In Figure 2, a typical Fußaufstands- flat A is shown greatly simplified. This footrest surface comprises a heel-up portion Fl, an out-of-stage support portion R2, and bale support portions Bl ... B5. The footrest area shown here also includes toe-toe cuts Zl ... Z5. By the sensor structure according to the invention, the pressure forces acting in the described Aufstandsabschnitten Fl, R2, Bl ... B5 and Zl ... Z5 detected at high clock frequency and converted into measurement signals.

As can be seen from FIG. 3, it is possible to integrate directly into the sensor structure a control circuit S1 provided for detecting the pressure measuring signals and converting them into digital data. In the exemplary embodiment illustrated in FIG. 3, the sensor structure is realized in interaction with a stocking. The control circuit S1 is in this case located at an upper edge region of the stocking 1. The control circuit S1 is preferably provided with a small energy storage device, in particular in the form of a button cell and further preferably comprises an interface, in particular a radio interface for transmitting the acquired data to a user in the area girdle or neck worn mainmemary circuit HS formed by, for example, a PDA, a mobile phone or other communication device equipped with a sufficient memory capacity. The main control circuit HS can be provided with a display device, via which individual step cycles, or even the time course of several step cycles can be visualized. The main control circuit can also be provided with a feedback device, for example in the form of an earphone 7, to give the user during the run an acoustic feedback for the control of the running kinematics.

As an alternative to the embodiment of the sensor device according to the invention described in connection with FIG. 3 in conjunction with a stocking, it is also possible to integrate these in a shoe sole or, in particular, as shown in FIG. 4 in a shoe insert. When integrating the sensor structure according to the invention into a shoe insert SE, it is possible to design the control circuit S1 as a printed circuit board and in particular to arrange it on the zone illustrated here, which supports the inner instep area of the foot. The sensor structure according to the invention can be designed so that it has fewer detection channels than previously described in connection with FIG. To monitor the foot kinematics, it may be sufficient to record information about the compressive forces in the area of the heel standing area F1 as well as in only two or three rebellion sections B1, B3 and B5.

FIG. 5 a shows, to a rough approximation, the pressure load for the footrest sections F1, B1, B3 and B5. These temporal pressure profiles recorded for the respective step can be classified by curve analysis criteria. In the example shown here, those points in time are marked in which the same area contents result under the pressure / time areas to the left of the respective marking and to the right of the respective marking.

As can be seen from FIG. 5b, it is possible to represent the temporal position of the points determined according to FIG. 5a as well as the average pressure load in the form of a polar diagram. In FIG. 5b, this diagram is shown by way of example for the series of measurements according to FIG. 5a. For subsequent steps SN, SN + 1, SN + 2, such polar diagrams can be generated.

As can be seen from FIG. 6, it is possible to process the measured values obtained for each step by a mapping function and to display the time profile of the evaluation results for the subsequent steps. On the basis of the graphic function on the basis of the graph according to FIG. 6, a warm-up phase P1, an optimum Running phase P2, a running phase P3 in which gradual fatigue is evident, a running phase P4 in which severe fatigue phenomena occur and a running phase P5 are detected with heavy exhaustion. By recording the running behavior for different training runs, it becomes possible to detect developments in running behavior and in particular training progress in the running technique. It is possible to optimize a therapy or a training concept on the basis of the running behavior analyzed according to selected evaluation concepts, in particular dynamic foot roll behavior.

It is preferably recorded in high data resolution, the time course of the surface pressure in selected zones of Fußaufsstandsflache for several steps. Information about the running characteristics is obtained from these data.

The sensor structure according to the invention is also suitable for observing the leg load during a convalescence phase. Thus, it is possible to estimate the load of the leg muscles on the FußaufStandskräfte and thus also the other loads on the leg muscles and the skeleton. The user can thus be communicated inadmissible in particular on acoustic loads. Furthermore, it becomes possible to determine whether sufficient movement work has been carried out for revitalization, or whether, for example, further movement exercises are required to fulfill a daily routine. The sensor structure according to the invention can also be incorporated into a support bandage.

Sensor structures according to the invention are preferably used in pairs, ie on the left and on the right foot. However, it is also possible to generate certain statements by using the sensor structure on only one foot. The sensor structure can also be designed such that it generates a measured value field for the entire potential foot print area with relatively high resolution-for example, in a hexagonal grid with a field-side spacing of 3 mm, preferably first group-based grouping of the measured values and assignment thereof to specific evaluation zones. These rating zones may then overlap. From such records, more in-depth statements about the foot load characteristics can be obtained. The scanning of the entire measuring surface is preferably carried out with a clock frequency of more than 80Hz. With this sensor structure, the quality of footbed systems can also be evaluated.

Claims

claims

1. Sensor structure for generating kinematics of a person indicative signals, wherein the sensor device comprises a plurality of sensor devices which are as such intended to provide indicative of local Aufstanddruckes or local Aufstandskraft indicative signals at several measuring points within a FußaufStandsfläche.

2. Sensor structure according to claim 1, characterized in that a first sensor is provided, which serves to detect the contact pressure in the heel area (Fl).

3. Sensor structure according to claim 1 or 2, characterized in that a second sensor is provided which serves to detect the contact pressure in the region (R2).

4. Sensor structure according to at least one of claims 1 to 3, characterized in that further sensors are provided for detecting the contact pressure in the areas M2 ... M5.

5. Sensor structure according to at least one of claims 1 to 4, characterized in that toe pressure sensors are provided for detecting the contact pressures in the footprints of the foot areas.

6. Sensor structure according to at least one of claims 1 to 5, characterized in that the sensors are designed as pressure sensors.

7. Sensor structure according to at least one of claims 1 to 6, characterized in that the sensors comprise a flexible layer and that the pressure is detected by the compression of each flexible layer.

8. Sensor structure according to at least one of claims 1 to 7, characterized in that the compression is detected by a change in conductivity.

9. sensor structure according to at least one of claims 1 to 8, characterized in that the compression is detected by a capacitance change of a capacitor structure.

10. Sensor structure according to at least one of claims 1 to

9, characterized in that the sensors are formed by a plurality of conductive layers, and that a signal indicative of the pressure is generated on the basis of a physical effect, which correlates as such with a compression of those layers.

11. Sensor structure according to at least one of claims 1 to

10, characterized in that the sensor devices are incorporated in a shoe insert.

12. Sensor structure according to at least one of claims 1 to

11, characterized in that the sensor devices are incorporated in a shoe

13. Sensor structure according to at least one of claims 1 to

12, characterized in that the sensor devices are integrated into a sock.

14. Sensor structure according to at least one of claims 1 to

13, characterized in that the sensor devices are designed as individually positionable on the foot sensor elements.

15. Sensor structure according to at least one of claims 1 to

14, characterized in that a signal preprocessing is provided for pre-evaluation of the generated via the sensor devices pressure measuring signals.

16. Sensor structure according to at least one of claims 1 to

15, characterized in that the signal preprocessing circuit converts the pressure measuring signals into digital signals.

17. Sensor structure according to at least one of claims 1 to

16, characterized in that the signals addressed are readable.

18. Sensor structure according to at least one of claims 1 to

17, characterized in that the signals are evaluated by an evaluation procedure.

19. Sensor structure according to at least one of claims 1 to

18, characterized in that via the evaluation procedure, a normalization approach is executed which, as such, allows an evaluation or a comparison of subsequent step cycles.

20. Sensor structure according to at least one of claims 1 to

19, characterized in that it is analyzed on the basis of the detected signals, whether the running kinematics met certain characteristics, and that feedback systems are provided which as such give the respective user of running information about the quality of the coordination of the activation of the running muscles.

21. Sensor structure according to at least one of claims 1 to

20, characterized in that based on the detected signals, the current degree of exhaustion of the user is determined.

22. Sensor structure according to at least one of claims 1 to

21, characterized in that a training run is documented on the basis of the detected signals.

23. Sensor structure according to at least one of claims 1 to

22, characterized in that evaluation results are generated for each step.

24. Sensor structure according to at least one of claims 1 to

23, characterized in that the evaluation results are stored for subsequent steps. the degree of correlation of the load pattern of each step is compared with a reference pattern.

25. Sensor structure according to at least one of claims 1 to

24, characterized in that the reference pattern is generated as an average load pattern.

26. Sensor structure according to at least one of claims 1 to

25, characterized in that the reference pattern is an ideal load pattern is used.

27. A method for detecting the walking behavior of a person in which by means of the respective foot associated sensor structures with respect to the contact pressure in selected zones of FußaufStandsfläche indicative signals are obtained and these signals are processed by an electronic data processing device.

28. The method according to claim 27, characterized in that the electronic data processing device is configured in such a way that the changes of the rolling characteristics can be visualized successively by them.

29. The method of claim 27, or 28, characterized in that the electronic data processing device comprises an interface for exporting the collected measurement data for further processing thereof.