CA2066802A1 - Custom seating simulator - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

A body shape simulator for sensing the shape of the human body and for producing a simulation of that shape which can thereafter be used to manufacture a body support having a customized shape conforming to the shape of the body, and in particular to a seating simulator for sensing the shape of the body when seated, and for subsequently manufacturing a chair customized to such shape.

Description

20~8~2 FIELD OF THE INVENTION
The invPntion relates to the manufacture of customized body supports such as seating, and to a body posture simulator, for use in such manufacture, and in particular to the manufacture of customi~ed seating for disabled personsO
BACKGROUND OF THE INVENTION
The human body is required to be supported on a variety of different supports for various different purposes from time to time. The most common support is a seat. However other supports such as beds, hospital operating tables and like must also be manufactured and adapted to support thP
body in particular positions.
In the case of seating, in some cases seats are required for persons having a particular physical incapacity, and they may also require arm rests, foot rests and head rests.
In all of these cases it is of course well understood that the size and shape of the human body varies widely from one individual to another and from one race to another.
However, in the great majority of cases the design of body supports does not at present lend itself to adaptation to such wide variations in proportions and shape~
The design and shapiny of chairs, for centuries past, has simply been based on an appro~imation of the needs of the average individualO Chairs were simply provided with a seating portion, a back portion, and some form of floor ' ~ ' ' ' ' , ~ ' , , 2~68~2 support. Chairs were lower, if they were required for so called lounge seating, and might be higher if they were required for work seating. Chairs might have various different features for work seating such as movable backs and the like so that they could in some way approximate to the body dimensions and seating position of the user.
However, beyond that very little has been accomplished to provide customized seating for individuals.
It is however becoming well-known by experts in ergonomics, that persons who for example may be required to work in a seated position for extended lengths of time, may be greatly affected by the comfort and design of the seat.
Almost invariably, after a length of time, seated persons ; will wish to get up and move around and "stretch their lags"
before again sitting down to work. In some cases, seating positions have been so poorly designed that they cause progressively poorer body postures, and may in fact impair ` the work capacity of the individuals.
However, when the situation of disa~led persons is considered, the situation is much more aggravated. A
disabled person is usually provided with a single wheeled chair, and such a person will spend almost their entire waking hours seated i:n~the one chair. It is not possible for them to get up and move~around. It is not possible for them to~move from one chair to another. In many cases it is simply not possible ~or them to even move within the chaix .

,, '''',' .'. ' '' 2 ~ 2 so as to periodically change their position.
It is in fact well-known in the medical profession that the standard designs of wheel chair offer significant disadvantages, and, like most solutions to the problems of seating, are based simply on an approximation of the needs of the average individual with the average disability, and do not take into account larger or smaller individuals, or individuals with specialized disabilities.
Studies suggest that between 40 to 70 % of wheelchair bound persons may be provided with seats of inadequate comfort and support. Various systems have been proposed including a modular fitting frame with segmented cushioning, pad matrix pressure profilers, dilation moulding frames, and foam deflection measurement using a potentiometer array.
Each of these has evaluated strategies for automation of production or carving of seat cushion contours and each has demonstrated improved tissue pressure distributions when ~eat contour is related to patient shape. Another proposal .;
suggests a system for 3D modelling and machining of wheelchalr cushions. Shape data capture is done by manual digitizing of selected grid points on a dilation seat after latex bags are consolidated to the shape of the client~ A
positive mould is then carved by NC machining and free rise foam is poured into this mould to form the cushion. These systems are unduly complex and expensive, and are not always completely effective.
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-` :` ' , '' ' '` ' ` ' 2~6~8~2 While the forgoing explanation has been particularly directed to the provision of a seating simulator for use in the production of customized seating, it will be appreciated, as e~plained above, that the invention is also applicable to the provision of other forms of body supporting devices such as beds, operating tables and the like.
For all of these reasons, it is therefore apparent that it is desirable to provide a system for the manufacturing of customized body supports, for example seating, and especially for manufacturing customized seating for disabled persons.
; However, in order to do so, some means must be provided for simulating the actual body shape, for example the seating position, of the individual, and then reproducing that simulation in the form of an actual body support, for ; example a seating unit.
~ BRIEF SUMMARY OF THE _NVENTION
:~. With the view to satisfying the various foregoing requirements, the invention comprises a body shape simulator, adapted to model the body shapa, for e~ample the seating position o~ an individual, and to record such a ~:; body shape for subs:equent manufacture of a~body supporting :
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~ : The:invent:ion further comprises a body shape simulator :
such as seating simulator wherein there:are a plurality of :
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206~g~2 contact bodies, and actuator msans for moving said contact bodies towards and away from a predetermined position, so that the contact bodies may be moved into optimal relationship with the body of an individual, thereby simulating and modelling the actual support which will eventually be required.
The invention further comprises a system of first of all modelling the seating position of an individual, and recording the same, and thereafter fabricating a mould lQ member conforming such simulated seating position, and thereafter fabricating a seating unit conforming to said mould member, whereby the seating unit will have a configuration specific to the indiqidual person.
Preferably, these functions are achieved in conjunction with electronic positional sensors, and memory means, and electrical operating means, whereby each individual actuator may be operated separately, to move its contact body towards . -and away from an individual, and to record the optimal position in electronic memory.
Preferably, the electronic controls will incorporate a visual display, visually displaying the actual appearance of the simulated seat for example upon which the p~rson is sitting, so that the individual may actually see movement of the seat:simulator and will be able to compare this with the comfort experienced by his, or her, body and thus optimize the end result. ~

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~"`' ' , ' ' ' , The various features of novelty which chara~t~ Q~
invention are pointed out with more particularity in th~
claims annexed to and forming a part of this disclosure.
For a better understanding of the invention, its operating advantages and specific o~jects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which there are illustrated and described preferred embodiments of -the invention.
IN THE DRAWINGS
Figure 1 is a perspective illustration of a saating simulator in accordance with the invention with a computer aided graphics design unit coupled thereto;
Figure 2 is an enlarged sectional illustration along line 2-2 of figure 1 of a single actuator and contact bod~;
Figure 3 is a perspective illustration showing a ~irst intermediate stage in the manufacture of an actual seating unit from the simulator;
Figure 4 is a perspective illustration of a second ~ method for the manufacture of such a seating unit, and, ; 20 Figure 5 is a perspective illustration of a cha r for a disabled person incorporating such a seating unit manufacturPd in accordance with the invention.
DESCRIPTION OF A SPECIFIC EMBODIMENT
Referring first of all *o Figure 1, it will be seen that what is illustrated here in general schematic form is the simulator unit designed for simulating an actual seating .

unit, and for adjustably varying the shape and con~oQr O~ ~ 2 the simulated seating unit, to suit the body of an individual.
For this purpose, the simulator comprises a seat module 10, and a back module 12, typically although not necessarily coupled together with hinge means 14, by means of which the angular position between the seat and the back may be varied. Each o~ the modules 10 and 12 comprises a back plate or base plate 16-18, and an intermediate bearing plate 20-22 spaced from, but parallel to, its respective back ; plate 16-18.
A large plurality of contact bodies 24-26 are provided extending upwardly from the sur~ace of the intermediate plate 20 and outwardly from plate 22. The contact bodies are in turn operated by actuators 28-30 (see Figure 2)~
The actuators are all individually operable in a manner to be described below, and are controlled through cable controls 32 and 34, and connecting cable 36, coupling the same to a CAD console 38.
:20 In order to provide a closer ~imulation to actualseating, a seating panel and back panel 40 and 42 .
respectively, preferably being comprised o~ a single integral piece o mat~erial are provided overlying the contact bodies 24 and 26. The~panel~ 40 and 42 are formed : ~ ~
of a~semi-ri:gid, seml-flexible ma~erial, typically;being : : comprised of a sandwich of synthetic materials having ~ 7 ; :

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2 ~ 0 2 various different properties.
The propertie~ of such panels 40 and 42 are such that the body o~ an individual seated on the panel 40 and resting on the panel 42, will have the same sensation as a person seated in a relatively hard chair. Preferably the properties of the panels 40 and 42 will be such that they span the spacing between the individual contact bodies 24 and 26 so that the person seated in the simulator is not conscious of the pressure of the individual contact bodies, but will merely sense variations in the actual contouring and shape of the panels 40 and 42 themselves. An additiona]
layer of foam material may be added to the surface to simulate cushioning of di~ferent densities.
As best shown in Figure 2, each of the actuators will be seen to comprise an elongated tubular sleeve 50, internally threaded as at 52, at one end. The sleeve 50 is adapted to slida to and fro in a longitudinal manner along a linear path, in the Iinear bearing 54. Bearing 54 is secured to its respective plate 20 (22), and to an intermediate support plate 55.
A threaded actuator rod 56 is supported in a rotary bearing 58 which is in turn mounted on its respective plate 16 (18).
A drive gear 60 is coupled to the screw 56, and is driven in turn by a driven gear 62, and stepper motor 64.
Separate stepper motors 64 are mounted together in . ' ' ' . ,, ' , : -': , .. . .

2~6~8~2 horizontal rows on support bars 66, so that complete rows of such stepp~r motors may be secured in position for operating a complete row of respective actuators.
Each of the individual stepper motors 64 is separately wired through wiring 32 (34) to connect to wire 36 which is in turn connected to the CAD terminal 38.
In this way, by the operation of the terminal 38 any one of the individual stepper motors 64 may be operated in either direction.
This will then cause the contact body connected thereto to move so that it either extends or retracts relative to its plate 20 (22).
-~ If desired, the hinge 14 may incorporate actuator mea~s 68 also connected to the CAD terminal 38, so that the angle of the seat and back may be changed relative to one another.
In operation, an individual will be seated on the seat and back modules 10 and 12, resting in fact on the surface of the panels 40 and 42, so that the person is out of , -i physical contact with the individual contact bodies 24, and is not in fact conscious of the individual pressure ~oints , .
crea~ed thereby.
An operator will then comm nce operating the various actuators, and the individual will give his or her reactions.
Eventually, the individual may wish to take over the ~ :
ine adjustment of the position and issue suggestions for 9_ :

' ' , ' ' ' 2~6802 the movement of individual actuators at various positions.
The assessment of the optimal shape may be aided by observations of the posture and bearing of the individual by a clinician, and by feedback from measurement instruments, including pressure transducers and the like, which may be placed on the surface of the seat or in the sub-surface, or which may be integral parts of the seat simulator system.
Eventually, assuming the individual is satisfied, the positions of all of the actuators is then recorded on electronic medium in the CAD terminal.
This will then enable the same actuator positions to be set up at a later date, for reasons to be described belowO
In ordar to effecti~ely treat a number of persons one after the other, the next person may then be seated, and the same operation commenced all over again, and the informatlon recorded once more.
; After the completion of a session of the seat simulation of the positions of a desired number of people, the manufacturing process of the actual chairs or seating units may then commence.
There are tWQ methods, one illustrated in Figures 1 and 3 and the other illustrated Figure 4.
Referring first of all to the method illustrated in Figures 1 and 3, the panel of material illustratad as 40-42 will be~replaced by a haated panel of thermoplastic material 40a-42a (Figure 3). The same reference numbers are used, , : ~:

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20~68~2 because the panel will be about the same size and shape, and all it would change is the nature of the material of which it is formed. The panel 40a-42a of thermoplastic material will first of all be hea-ted up, in any suitable heating device or o~en illustrated schematically in Figure 3 as 70, so that it becomes soft and malleable.
In this case, it will seen as shown in Figure 1 that the actuators are moved into a desired previously recorded position for a specified individual.
The panel 40a-42a of heated malleable thermoplastic material is then placed against the actuators, and is pressed into position, and is allowed to sit.
When removed, it is then used as the seating surface for a seat typically such as a wheelchair illustrated in Figura 5 as W.
In accordance with a further method of manufacture, as illustrated in Figure 4, an intermediate step is first of all performed.
- In this method, the contact bodies 24-26 are moved into positions which are a mirror image of the positions established for a particular individual. In other words those contact bodies which were extending outwardly are now retracted and those which were retracted are now extended outwardly. Panels of thermoplastic material indicated as 72-74 are placed over the contact bodies, and ridged back covers 76-78 are located over and secured to the panels 7~-;~ ~
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74, and define a hollow spaces. The back covers and parl21s are held in such position by any suitable means not shown.
By an injector mechanism indicat.ed as 78, foam plastic 80 is then in~ected into this space between the ridged back panel and the thermoplastic panel, thus forcing the thermoplastic panel to conform to the shape of the actuators.
The foam is then allowed to cure, and the seating and back units are then removed.
When removed with the back covers, the thermoplastic panel 72-74 will thus provide an accurate reflection of the position of the actuators, as originally set for a particular individual. This were a method of manufacture while being somewhat more costl~, may provide for a cushioned form of seating, which may be more desirable in some cases.
Given suitable manufacturing technigues, it is entigely possible and within the bounds of the state-of-the-art at present, to inject a sufficient quantity of foam to fill the cavity defined by the back cover, with an adequate quanti~
of foam to provide resilient but supportive cushioning for the seating unit.
;~ In the~final operation the se;at and back units are placed in a typical wheelchair W, Flgure 5, and is then ready for use by the individual for whom it was designed.
It will of cou~se be apprecla$ed that while these -12~

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2~6~2 operations have been described specifically in a~sociation with the manufacture of seating units for the disabled, the invention can equally well be applied to the manufacture of customized seating units for any individual who wishes to go to the expense of employing the techniques of the invention.
Thus executives, or any other persons such as computer terminal operators or business machine operators or the like may employ these techniques to provide customized seating.
It is also envisaged that customized seating will be provided in this way for automobiles, racing cars, aircraft, and the like, and the invention is not specifically confined either to seating units for the disabled, nor to seating units of any particular shape or size or use.
Furthermore the invention is equally well suitable for the provision of portions o~ seating units, or even for the provision o~ other forms of support such as reclining units, and specialized mattresses or beds.
Furthermore, the principles in the invention may also be applied to the provision of customlzed supports for injured portions of the body such as persons with broken limbs for example so that in this way customized supports may be provided to replace the conventional surgical cast usually used for this purpose.

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:' 2û~02 The invention i5 also helpful to designers of non customized seating who wish to obtain data on appropriate "average" seat shapes for markets or populations, targeted for particular seating products. The system can be used to produce, at least, prototype modes for such seating. Extra modules may be added and positioned appropriately to simulate a bed, or an operating table or other supportive surfaces, such as arm rests, head rests, foot rests and the like.
There may be advantages in providing a surgical operating table which actually incorporates tha simulating system o~ the invention. In this way, the actual shape and - configuratian of the operating table may be adjusted from ,.
one patient to another to hoth optimize patient comfort~ and also to assist in holding the patient in the optimum position for any particular operation being performed.

The foregoing is a description of a preferred embodiment of the invention which is given here by way of example only. The invention is not to be taken as limited to any of the specific features a~ dascribed, but - comprehends all such variations thereof as come within the scope of the appended claimsO

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Claims (9)

1. A seating simulator, adapted to model the seating position of an individual and to record such a seating position for subsequent manufacture.

2. A seating simulator as claimed in Claim 1 wherein there are a plurality of contact bodies, and actuator means for moving said contact bodies towards and away from a predetermined position, so that the contact bodies may be moved into optimal relationship with the body of an individual, thereby simulating and modelling the actual seat which will eventually be required.

3. A seating simulator as claimed in Claim 1 and including positional sensor means, and memory means, and electrical operating means, whereby each individual sensor may be operated separately, to move a respective contact body towards and away from an individual, and to record the optimal position in memory means.

4. A seating simulator as claimed in Claim 3 and incorporating a visual display visually displaying the actual appearance of the simulated seat upon which the person is sitting, so that the individual may actually see movement of the seat simulator and will be able to compare this with the comfort experience by his, or her, body and thus optimize the end result.

5. A posture simulator as claimed in Claim 2, and wherein said actuator means for said contact bodies comprise support rods upon which said contact bodies are mounted, bearing means for slidable bearing receiving said support rods for relative movement to and fro, threaded means engagable with said support rod means, and being rotatable whereby to move said contact bodies to and fro, and, individual motor means for driving rotating said threaded means, whereby each individual said contact body may be operated, by operation of its own individual motor means.

6. A posture simulator as claimed in Claim 5, and including front plate means, said slidable bearing being secured thereto said front plate means, and opening means in said front plate means whereby said contact body maybe located in front of said front plate means, and said support rod means may be located behind said front plate means and may be extendable and retractable with respect thereto, and further including back plate means, said threaded drive means extending through said back plate means, and said motor means being secured to said back plate means.

7. A posture simulator as claimed in Claim 2, designed for simulating a seating posture of an individual, and comprising a seating portion and a back portion, and movable means interconnecting said seating portion and said back portion, whereby the same may be moved relative to one another, and contact body means associated both with seating means and said back means, whereby to simulate the seating position of an individual when seated thereon.

8. A seating simulation system comprising the steps of first of all modelling the seating position of an individual, and recording the same, and thereafter fabricating a mould member conforming such simulated seating position, and thereafter fabricating a seating unit conforming to said mould member, whereby the seating unit will have a configuration specific to the individual person.

9. A method of simulating a posture as claimed in Claim 8 and including the steps of moving contact bodies into a preliminary posture position, positioning a person on said contact bodies, moving said contact bodies to simulate the actual posture of that person, and record the position of said contact bodies, for the subsequent manufacture of a body support therefrom.