GB2262810A

GB2262810A - Posture control device

Info

Publication number: GB2262810A
Application number: GB9226715A
Authority: GB
Inventors: David Brian Foden; Jeremy Robert Wilson
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-12-24
Filing date: 1992-12-22
Publication date: 1993-06-30
Also published as: GB9226715D0; GB9127360D0

Abstract

A posture control device comprising a flexible transducer strip 10 removably attachable to a belt (11) or vest (19) to be worn by the user, the transducer producing an electrical signal according to a change in physical configuration of the transducer strip brought about by a change in posture of the wearer. The electrical signal is fed to a receiving unit 1 having visible and/or audible and/or vibratory warning indicators to alert the user when the assumed correct posture is lost. A sensitivity switch 4 is provided to enable the sensitivity to be selected according to the users activity. The transducer may comprise a plurality of variable potentiometers or inductors. The electrical signal may be fed to the unit 1. The indicator may be a row lights 16 indicating curvature deviations 7, 8 in opposite directions. <IMAGE>

Description

A POSTURE CONTROL DEVICE THIS INVENTION relates to a posture control device. A common problem among many people is back pain, often due to prolonged periods of incorrect posture at home or at work.

Complaints either related to or referred from spinal disorders are growing in number. Spinal problems occur in the Lumbar Thoracic and Cervical regions. It is commonly known today that most hours are lost in industry due to back related problems.

Physiotherapists believe that measures taken towards posture correction can relieve and, in some instances, cure back and spine related problems.

Several devices have been used previously in an attempt to correct poor posture at home and in the work place, such as special cushions, back rests, corsets and other supportive devices.

These devices usually have the effect of suggesting to the user that correction is taking place, whereas what is perhaps happening is that they are simply supporting their back problem whilst physically not rectifying it. Back related problems may be eliminated or at least relieved by re-educating the critical areas of the spine to hold correct posture by use of a posture control device.

Good posture is instinctive in most infants. However the physical mechanics of the spine that maintain good posture are often abused or merely become redundant during our normal daily activities.

Thus the body's ability to hold good posture is lost. A re-education of the spinal structure is necessary for the correction and maintenance of correct posture.

An object of the present invention is to provide a device which enables the user to re-educate the spine to hold correct posture by physically strengthening the regions of the spine which maintain good posture.

According to the present invention, there is provided A posture control device comprising at least one flexible transducer strip the electrical characteristics of which change according to a change in the physical configuration of the or each strip, means for attaching the or each transducer strip to the body, and a receiving unit adapted to produce a visible and/or audible and/or vibratory indication responsive to an electrical signal generated as a result of a change in physical configuration of the or each transducer.

In certain working situations where bad posture is inherent in the use of a piece of equipment i.e. a computer terminal, the device may be used as a constant monitor of postural position.

Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figs. 1 and la illustrate a posture control device in accordance with the invention, incorporating a transducer, a receiver unit and a lumbar belt; Fig. 2 illustrates, in more detail, one form of transducer; Figs. 3a to 3c illustrate the flexural characteristics of the transducer; Fig. 4 is a block diagram showing a signal flow path of the receiver unit; Fig 5 is an electrical circuit diagram for the receiver unit; Fig. 6 illustrates correct posture alignment; Fig. 7 illustrates incorrect posture alignment; Figs. 8 and 8a illustrate a posture control device in accordance with another embodiment of the invention; Fig. 9 illustrates, in more detail, another form of transducer;; Figs. 10a to 10c illustrate the flexural characteristics of the transducer shown in Fig. 9; Fig. 11 is a block diagram showing a signal flow path of a modified receiver unit; Fig. 12 illustrates, in more detail, a further form of transducer; Fig. 13 illustrates, in more detail, a still further form of transducer; Fig. 14 is a block diagram showing a signal flow path of a further receiver unit; and Fig. 15 is a block diagram showing a signal flow path of a still further receiver unit.

With reference to Figs. 1 and la, this first example of a posture control device provides a single point measurement system including a transducer strip 10 in conjunction with a receiver unit 1 and a Lumbar belt 11.

Referring to Fig. 2, the strip 10 is composed of a flexible plastic strip 60 upon which is adhered a variable resistor 40.

The variable resistor 40 is a multi-turn "preset" type modified so that its resistor wiper may be freely moved laterally in and out of the resistor housing. This wiper is then attached to a length of 0.34 gauge piano wire 30. This wire is then passed through six nylon tubes 20 and attached firmly to an anchor point 12. All of the nylon tubes 20 are seated on and adhered to a strip of double sided adhesive rubber 50.

With reference to Figs. 3a and 3c, when the strip 10 is placed flat as in Fig. 3a, the resistor wiper will be in a central or null position. Bending the strip in the direction shown in Fig. 3b will cause the wire 30 to move into the resistor wiper into the resistor 40 giving a change in impedance therein. Bending the strip in the direction shown in Fig. 3c will draw the wire 30 out of the resistor to give an opposite change in impedance. These electrical changes are processed by the receiver unit of Fig. 1, as will be described.

The strip 10 is preferably sheathed in a fabric covering to which several fastener tabs 13 are fixed. The fasteners may be touch and close fasteners.

There are three connections required between the strip 10 and the receiver unit 1. These connections are fed from the strip via a flexible multi-core cable 14 and a Stereo mini jack 9.

With reference to Fig. la, the belt 11 is used to hold the strip 10 on the spine in the lumbar region. This belt is made from an elasticated material to which is attached a fastener strip 15 compatible with the fasteners on strip 10. The strip 15 is located in the centre of the belt 11 to allow attachment of the transducer strip 10. To each end of the belt 11 are attached further similar fasteners to allow easy fitment to users of various waist sizes. Referring again to Fig. 1, the receiver unit is comprised of a plastics or similar material housing case which conveniently occupies no more space than a small pocket calculator or radio pager, within which is contained the necessary electronics to allow the unit to function. Mounted on the side of the unit is a stereo mini jack socket 2 to allow the connection of the transducer strip via jack plug 9.

A power switch 3 enables the unit to be switched on and off.

A HI/LOW switch 4 allows the user to select the sensitivity of the device. A centre offset rotary control 5 allows the user to set a centre reading or null point of the device as will be described.

On a graduated scale indicator 16, an illuminated green centre marking 6 gives the user visual indication of a correct reading from the back strip 10.

An illuminated red marker 7 indicates movement of the back strip corresponding to hyper extension of the lower back, and a further illuminated red marker 8 indicates deflectional movement of the lower back.

Fig. 4 illustrates a signal flow path within the device 1.

With reference to the electronic circuit diagram Fig. 5, a Strip Input comprises connections for a fixed DC voltage, ground and wiper connections. The Wiper connection is fed to an operational amplifier A with fixed gain. Also fed into the amplifier A is an offset control comprising a positive and negative feed to either end of a potentiometer. The wiper of this potentiometer is then fed via a mix resistor into the first fixed gain amplifier. The resultant voltage of the transducer strip wiper and the Offset control 5 is then fed into a dual gain amplifier B having two gain settings altered by the sensitivity switch 4.

The resultant DC voltage from the second stage is fed into a 1096 19-segment LED 'dot' type driver C. The voltage from the strip therefore produces an indicated level on the display with integral offset control. Two comparators D each with adjustable level setting, provide limits for which a sounder E will be operated.

In operation, the transducer strip 10 is firmly attached inside lumbar belt 11 by means of the fastener strip 15.

The belt 11 is then pulled around the waist and fixed by the fasteners, making sure that the transducer strip 10 is approximately aligned with the centre of the spine in the lumbar region as illustrated in Fig. 6.

Once the belt is in position, the jack plug 9 from the sensing strip 10 may be plugged into socket 2 of the receiver unit 1.

The device is switched on using the power switch 3, and the user should assume the posture of "correct alignment" Fig. 6, and adjust the centre offset control 5 causing the display to illuminate the green marker centre position 6.

Movement towards bad posture, either backwards as in Fig. 6 or forwards as in Fig. 7, will, via the transducer strip 10, be registered by the receiver unit illuminating a red warning marker 7 or 8 respectively and by sounding an alarm beep.

This tells the user to return to the correct posture previously assumed, whereupon the display will re-centre and the alarm will stop.

The sensitivity of this alarm signal may be controlled by the sensitivity switch 4 in accordance with the user's physical activity or inactivity, e.g. walking, standing, lifting, typing, sewing or relaxing.

The sensitivity adjustment makes the device suitable for many day to day postural situations and activities.

With reference to Figs. 8 and 8a, in a second embodiment, the device includes a single transducer strip 11 as in the embodiment of Fig. 2 and also a double transducer strip 17 in conjunction with a dual receiver unit 18 and full body vest 19.

Due to the complex nature of movements in the cervical area of the spine, it may be necessary to use a double transducer strip.

Referring to Fig. 9 the strip 17 is composed of a flexible plastic strip 60 upon which is adhered two variable resistors 40.

The variable resistors 40 are of the multi-turn "preset" type but modified so that the resistor wiper may be freely moved laterally in and out of the resistor housing. These wipers are then attached to a length of 0.34 gauge piano wire 30 which is passed through four nylon tubes 20 and attached firmly to a central anchor point 12. All of the nylon tubes 20 are seated and adhered to a strip of double sided adhesive rubber 50.

With reference to Figs. 10a to 10c, when the strip is placed flat both resistor wipers will be in a central or null position.

Dual bending of the strip as shown in Fig. 10b will cause both of the resistor wipers to move giving changes in impedance. Dual bending of the strip as shown in Fig. 10c will give an opposite change in impedance on both resistors. These electrical changes may then be processed by the dual receiver unit 18.

The strip assembly may be sheathed in a fabric covering to which several fastener tabs are fixed.

There are five connections required to attach the strips to the receiver unit 18. These connections may be fed from the strip via a suitable flexible multi-core cable 20 and terminated to a five pin "Din" audio connector 21.

With reference to Fig. 8a, a full body vest 19 is used to hold both strips on the spine. This vest is made from elasticated material to which is sewn a fastener strip 22. This is located in the centre of the vest to allow attachment of the sensing strips. The single transducer strip 11 may be fitted in the Lumbar region of the vest 19. The double strip 17 is fitted to the Cervical region or the Thoracic region shown in Fig. 8a.

The dual receiver unit 18 is comprised of a plastics or similar housing case within which is contained the necessary electronics to allow the device to function. Mounted on the side of the case is a 5 pin "Din" audio socket 23 to receive the plug 21.

A power switch 3 enables the device to be switched on and off.

A HI/LOW switch 4 allows the user to select the sensitivity of the device.

An auto centre switch 26 allows the user to set the good reading of the unit as will be described.

Illuminated green upper and lower "good" indicators 27 give the user visual indication of correct posture readings from the transducer strips.

Illuminated red upper and lower bad indicators 28 indicate movements of the transducer strips corresponding to bad posture in the cervical and Lumbar regions respectively.

Figure 11 illustrates a signal flow path within the device.

In use, the single transducer strip 11 is firmly attached inside the Lumbar region of the vest 19 by touch and close fasteners.

The double transducer strip 17 is similarly attached inside the cervical region of the vest 19.

The full body vest 19 is worn like a normal vest, and the nature of the garment will ensure that the sensing strips 11 and 17 are approximately aligned on the centre of the spine.

Once the vest is in position the "Din" plug 21 from the strips 11 and 17 may be plugged into the receiving unit socket 23.

The receiving unit may now be switched on using the power switch 3, and the user may assume the correct posture as shown in Fig. 6. This also corresponds to the illustration 9 on the front panel of the unit 18 as shown in Fig. 8. The user then presses the Auto Centre switch 26, whereupon the two "good" indicators 27 will illuminate indicating good posture in both areas of the spine.

The two transducer strips 11 and 17 will monitor any deflection in the Lumbar and Cervical spine regions. Movement from correct posture in either of these regions will cause the corresponding "bad" indicator 28 on the receiving unit to illuminate and the sounder will produce an alarm beep.

The wearer must then re-assume good posture in the corresponding regions of the spine in order to turn off the sounder and re-illuminate the two "good" lights 27.

The sensitivity of this alarm signal may be controlled by means of the sensitivity switch 4 in accordance with the user's physical activity or inactivity e.g. walking, standing, lifting, typing, sewing or relaxing.

In addition, a stored setting may also be entered on the device. This setting may be stored by the user or by a treating physiotherapist. First it is necessary to ensure that the user is wearing the garment correctly. Upon assuming a correct posture the auto centre switch 26 is pressed and held down whilst a store switch 25 is pressed. This setting is then stored within the device for the user to recall when fitting the vest.

As previously described in relation to Figs. 8 to 11, it is possible to measure the curvature of specific regions of the spine.

However it is also possible to measure the complete spinal curve by use of a multi-part transducer strip as shown in Fig. 12.

This multi-part measurement system incorporates the same fundamental principles as the single and double systems, whereby multi-turn potentiometers 4 are fixed to a flexible strip 6. However, in this example each resistor wiper is attached to the preceding resistor housing by means of a short length of flexible rubber tube 37.

The completed strip may be used in conjunction with the "full body vest" as shown at 19 in Fig. 8a.

Each resistor wiper may then be electrically connected to a multiple-part receiver unit which operates as illustrated in the block diagram of Fig. 14.

The increase in quantity of information introduces the need for a micro processor which in turn enables accurate display of the curvature of the spine being measured on a small liquid crystal display.

Fig. 13 illustrates an alternative multiple-part measurement system which operates by proximity induction. Two inductors 48 are housed in electrical potting compound or suitable thermo-plastic 40 and are bonded to a flexible strip 6. The inductors 48 are connected in parallel to provide a source emission for measurement. Corresponding receiving inductors 49 are individually terminated to a multiple-part receiving unit which operates as illustrated in the block diagram of Fig. 15.

With all the aforementioned systems for postural measurement it is possible, with a suitable interface, to connect any of the transducer strips to a computer terminal. By the use of a small programme an audible and/or visual alarm may alert the computer user to any postural mis-alignment during normal work at the computer.

The most straightforward interface is the commonly used RS 232. This simple method of data transfer would be adequate for the amount of data that would pass between the device and a host computer. The serial data could then be de-coded and represented on screen for the user's attention at all times. It is most important that whilst this may be practical from a stand alone programme point of view, the programme which displays the information must be able to run in conjunction with most commonly used application software.

Preferably, the display programme should be present on screen (albeit a small symbol and sound alarm) at all times, and therefore must be memory resident and co-existent with usual applications using recognised programming structures and methods.

A dedicated interface can be designed which would fit within most types of computer having expansion slots available for such an interface.

The audible sounder may be replaced by a vibrating mechanism. This would allow the user to "feel" a loss of good posture and may be particularly useful if the device is to be used in an office environment.

A radio signal transmitting belt and associated reception electronics in the unit could replace the cable interface. Signals would need to be encoded if multiple units were used within a local working environment. It may be possible to use infra red as an alternative to radio signals.

A rechargeable battery pack may be incorporated into the unit. This would enable the unit to be manufactured with a water and tamper proof cabinet.

Alternative displays may be used. Several alternative right/wrong visual display methods may be incorporated into the unit with relatively small amounts of change to the overall design of the unit. For example, a single LED could be used. This would display nothing when the unit is "set" and the user remains within the tolerance window selected and then simply illuminate if either of the two trigger thresholds had been surpassed. Alternatively, a single multicolour LED may be used. Devices are available which display three different colours, such as yellow for hyper extension, green for correct and red for over extension. Yet again, a multi LED display may be used allowing degrees of good or poor posture to be displayed from a fixed centre point. Most or all of these methods of display could incorporate (as a dual function) a battery level indicator.

Claims

1. A posture control device comprising at least one flexible transducer strip the electrical characteristics of which change according to a change in the physical configuration of the or each strip, means for attaching the or each transducer strip to the body, and a receiving unit adapted to produce a visible and/or audible and/or vibratory indication responsive to an electrical signal generated as a result of a change in physical configuration of the or each transducer.

2. A posture control device according to Claim 1, wherein the transducer strip comprises at least one variable potentiometer and at least one elongate member attached to the slider of said potentiometer and anchored to the transducer strip at a position remote from the potentiometer such that bending movement of the transducer strip causes said elongate member to alter the position of the slider in the potentiometer.

3. A posture control device according to Claim 1 or Claim 2, wherein said transducer strip is adapted to be removably attached to a belt or garment to be worn by the user such that the transducer strip is positioned on or close to the spine at a selected level thereon, and wherein said transducer strip is connected by a flexible lead to the receiving unit.

4. A posture control device according to any preceding Claim, wherein the means for attaching the transducer to the body is a belt to be worn in the lumbar region.

5. A posture control device according to any one of Claims 1 to 3, wherein said means for attaching the transducer to the body comprises a vest having fastening means thereon to receive one or more transducer strips.

6. A posture control device according to any preceding Claim, wherein said means for attaching the or each transducer strip to the body comprises one or more strips of touch and close fastener.

7. A posture control device according to any preceding claim, wherein said receiving unit includes a plurality of indicator lights adapted to display conditions of correct and incorrect posture.

8. A posture control device according to any preceding claim, wherein said receiving unit comprises a centre offset control whereby the unit may be set up to display correct posture responsive to a signal representing a selected actual posture from the transducer.

9. A posture control device according to any preceding claim, wherein said receiving unit includes a sensitivity control such that a user may select a degree of sensitivity of the device according to an expected amount of change in physical configuration of the transducer.

10. A posture control device according to any preceding claim, wherein said transducer strip comprises a plurality of variable potentiometers and a plurality of elongate members attached respectively to the wipers of said potentiometers, each said elongate member being anchored at a position remote from its respective potentiometer.

11. A posture control device according to Claim 10, wherein each elongate member, being attached to the wiper of a respective potentiometer is anchored to a fixed casing member of another of said potentiometers.

12. A posture control device according to Claim 1, wherein said transducer comprises a flexible strip upon which are mounted a plurality of inductors connected in parallel to provide a source of emission for measurement, and a plurality of corresponding receiving inductors also mounted on the transducer strip in spaced relationship to the emission inductors such that flexural movement of the strip produces an output signal from said receiving inductors which is fed to said receiving unit.

13. A posture control device according to Claim 1, wherein said receiving unit includes an electronic memory whereby a stored setting may be imposed upon the receiving unit corresponding to an established correct posture.

14. A posture control device according to any preceding claim, in which said receiving unit includes a connection for an interface with a computer whereby a visible and/or audible indication may be displayed on screen during normal work at the computer.

15. A posture control device according to Claim 1, wherein the transducer strip and/or the receiving unit includes a vibrating mechanism actuated in response to said electrical signal from the transducer.

16. A posture control device according to Claim 1, in which said transducer strip includes a signal generator whereby radio or infra red signals may be transmitted to the receiving unit.

17. A posture control device according to any preceding claim, wherein the receiving unit includes a rechargeable battery pack.

18. A posture control device according to Claim 1, wherein said receiving unit includes a single multi-colour LED to produce said visible indication by means of a multi-colour display, each colour representing a predetermined posture condition.

19. A posture control device according to Claim 1, in which a visible indication is provided on said receiving unit by means of an array of LED adapted to indicate degrees of good or poor posture displayed from a fixed centre point.

20. A posture control device according to any preceding claim, in which said receiving unit includes a battery level indicator.

21. A posture control device substantially as hereinbefore described with reference to the various embodiments illustrated in the accompanying drawings.