Manufacturing of a Wheelchair Cum Stretcher for a Variety of Uses

Manufacturing of a Wheelchair Cum Stretcher for a Variety of Uses

1Assistant Professor, Mechanical Engineering Department, School of Management Sciences Lucknow, Uttar Pradesh, India

2B.Tech Mechanical Engineering Scholar, School of Management Sciences Lucknow, Uttar Pradesh, India

3B.Tech Mechanical Engineering Scholar, School of Management Sciences Lucknow, Uttar Pradesh, India

4B.Tech Mechanical Engineering Scholar, School of Management Sciences Lucknow, Uttar Pradesh, India

5B.Tech Mechanical Engineering Scholar, School of Management Sciences Lucknow, Uttar Pradesh, India

6B.Tech Mechanical Engineering Scholar, School of Management Sciences Lucknow, Uttar Pradesh, India ***

Abstract - In hospitals, airports, train stations, retail centers, etc., wheelchairs and stretchers are frequently utilized. Depending on the needs, this design is a modified wheelchair stretcher. According to the needs, this device can be utilized to transform a wheelchair into a stretcher. This can be manually accessed. When the levers are pulled, the chair becomes a stretcher. According to the patient's and the doctors' convenience, the stretchers can be removed from the main frame, making it simpler to carry and access the patient. With the help of the folding mechanism, it is simpler to store several stretchers in the shape of chairs in a comparably small amount of space. Every day, there are more patients in the world. Therefore, it is dangerous for patients to be transferred from a wheelchair to a stretcher, a bed to a wheelchair, or vice versa, in hospitals. A wheelchair cum stretcher is required to improve the mobility of impaired patients and to supply cutting-edge medical technology for usage in hospitals.

Key Words: Medical equipment, folding mechanism, stretcher, wheelchair, etc.

1. INTRODUCTION

Achairwithwheelsisawheelchair.Thedevicecomesin manydesignsthatallowforelectricpropulsionbymotorsor manualpropulsionbythesittingoccupantmanuallyturning therearwheels.Theseatfrequentlyhashandlesbehinditso thatsomeoneelsecanpushit.Peoplewhofinditdifficultor impossibletowalkduetoanillness,accident,orhandicap usewheelchairs.Awheelbenchisfrequentlyusedbypeople whohavetroublestandingandwalking.Theearliesthuman creationswerethewheelandthechair[1].Awheelchairisa wheeled mobility aid created specifically for people with disabilities.Themachinecanbemovedmanuallybyspinning the wheels by hand or automatically using a variety of systems[9].Peoplewhofinditdifficultorimpossibletowalk owingtoaphysicalorphysiologicalcondition,aninjury,ora handicap use wheelchairs. Early wheelchairs were solely designedtofacilitateadisabledperson'smovementfromone location to another, but today's wheelchairs are seen as a meansofbothtransportationandpersonalexpression.The

number of disabled people in India has significantly increased in recent years[3].Many people have congenital limitations,asmallfractionareaccidentvictims,andvarious typesofmobilityequipmentareanunavoidablepartoftheir dailylives.

Amobilityaidisatoolcreatedtoassistpersonswhohave mobility impairments in moving around or to generally improve their mobility. There are several walking devices thatcanhelppeoplewhohavetrouble walking,aswell as wheelchairsormobilityscootersforpeoplewhohaveamore severeimpairmentorwhoneedtotravelfartherthanthey normally would on foot[4].The white caneand guide dog have been used formanyyears bythose whoare blindor visually impaired. Other aids can be used to help with transfers or mobility inside a building or in areas where there are variations in level. The term "mobility aid" has typicallybeenusedtorefertolow-techmechanicaldevices. Thephrasecanalsobeseeninofficialpapers,suchasthose thatdiscussdifferenttypesoftaxbreaks.Itdescribesthose gadgets that allow for a degree of independence of movement akin to that of unsupported walking or rising fromachair.Wheelchairsthatcanbemanuallymovedbythe useroracompanion[2].Userscangoforwardandbackward at rates determined by how much force they can use by manipulatingthepushrims.Theycanalsoturnleftorright and pass over nearby dips and peaks. Four tiny wheels protrudefromasmallplatformonawheelbasechair,also calledascooter.Thekindofchairthatisputonthisplatform variesdependingontheuser'sdemandsanddisability;some areevenmadefromamoldoftheuserintheiridealsitting posture. The wheelbase chair's controls are attached to a frame that curves upward from the platform's front to a heightandpositionthatiscomfortablefortheuser.Thetop of the frame is coupled with a horizontal steering bar. A stretcherisamedicaltoolusedtocarrypatientsforabrief period of time. It features grips on either side of the stretcher'slengthtomakeiteasiertocarry[7].Astretcheris a mobile bed on wheels used to move patients who are unabletowalkorstandunaided.Peoplewhoareincritical condition and accident victims are transported from one location to another using stretchers. The design is

straightforward,supportingthepatientonametalbedatthe topandhavingametalframewithcasterwheels.Stretchers have been employed on battlefields and in emergency situations when rocky terrain makes wheeled vehicles impractical since antiquity. They typically consisted of a canvas sling with long sides that were stitched to one anothertocreatepocketsthroughwhichwoodenpolescould bepassed.Stretchersarenowmadeofarangeoflightweight materialsandhavefittingsthatallowthemtobeattachedto other devices. The term "mobility aid" has typically been usedtorefertolow-techmechanicaldevices.Thephrasecan also be seen in official papers, such as those that discuss differenttypesoftaxbreaks.Itdescribesthosegadgetsthat allowforadegreeofindependenceofmovementakintothat ofunsupportedwalkingorrisingfromachair.

Modernwheelchairsaremadeoflightweightmaterials and have much more advanced features that are microprocessorcontrolled.Today'swheelchairmarkethas undergonearevolution,drivenbyhumanneedsanddesires. Betterwheelchairoptionsareanticipatedinthefuturethat could accommodate human inventiveness and benefit the less fortunate[6].Several components make up the wheelchair's basic structure. It is merely a set of wheels mountedtoachair,toputitsimply.Therearesomeessential components that every wheelchair must have. To prevent fatiguefromsettingdownonaseatforanextendedperiodof time,itmustbecomfy.Itoughttohaveabackrestthatoffers enoughlumbarsupport.Itmusthaveafootrestaswellasan armrestattheidealheight.Themostcrucialneedisthatthe wheelshavebrakes.Thewheelchair'sdesignhasundergone numerousalterationssinceitwasfirstinvented.Thereare many different types of wheelchairs available today, includingfolding,rigid,electric,andself-propelledmodels. Other categories include standing wheelchairs, sports wheelchairs, mobility scooters, toilet wheelchairs, stairs climbingwheelchairs,etc.basedontheirintendeduse.The variety of wheelchairs reflects the requirement to accommodatedifferentneeds.

The objective of the work are.

 A developed stretcher or wheel chair allows a caregiverornursetotransferapatientconveniently fromabedtoastretcherandviceversa.Mobilityis relativelysimpleinbothconfigurations,bothona stretcherandinawheelchair.

 Providingadetachablestretchertomakeitsimple tomovethepatient.

 When the stretcher is removed, the base can be usedasawheelchair.

 Creating a prototype model with constrained suppliesandscarps.costdecreaseasaresult.

2. DESCRIPTION

Themajor component involved in the construction of theWHEELCHAIRCUMSTRETCHERare:

 Chassis

 Rearwheel

 Casters

 BoltandNut

 Mainbasestructure

 Bearing

 RackandPinionGear

A. Chassis

Thebaseisessentiallyaplatformorwhatisreferredtoas the assembly's support. Metal channels consisting of aluminum,mildsteel,stainlesssteel,etc.areusedtoformthe basis. This wheelchair's base is made up of a framework knownasaframethatiscomposedofmildsteel.

The individual cansit ona platform made ofmetal thatis fastenedtotheuppersurfaceoftheframe.Inessence,the weldingprocedureisusedtojointhesheettotheframe.Arc weldingisthetypeofweldingusedinthisdesign.Whenthe frame and sheet metal are connected, a hard structure knownasthefoundationiscreated.

B. Rear Wheels

Theshaftthatconnectstherearwheelstooneanotherkeeps them in alignment. The wheel has a 69mm diameter. This wheelwillsupporttheweightoftheentirebody,including thatoftheuser.

C. Casters

End bearings and bearing caps are used to secure the casterwheelstothechair'sframe.Thewheeliscomprisedof inch-diameterfiberwheels.Acaster(alsoknownasacastor) is an undriven single, double, or compound wheel that is intendedtobemountedtothebottomofabiggerobject(the "vehicle")tomakeiteasiertomove.Thematerialstheyare oftenmadeofincluderubber,plastic,nylon,aluminum,or stainlesssteel,andtheycomeinarangeofsizes.Foroptimal balancingandeasydirectionchanges,wehaveincludedtwo casterwheelsinthefrontofthisitem.

D. Principal framework

Theseatplatformislocatedonthis,whichisthemainbase. Here,thewheelshaftandbasearejoinedbywelding.Itis detachablebecausethenutsandboltsareusedtosecurethe wheels.Inordertokeepthebaselegremovableincasewe needtoreplacethecaster,thecastersarealsoattachedtoit.

E. Bearings

Because the bearings could break if they were hammered intotheshaft,theyarepressedintoplacesmoothly.Boththe bearingandthebearingcaparecomposedofsteel.Inorder toreducefrictionandpowerloss,ballandrollerbearingsare commonlyemployedintoolsandmachinery.Ballbearings havebeenaroundsinceatleastLeonardodaVinci,although their design and production have advanced significantly since then. It took years of research and development to bring this technology to its current degree of perfection. Whenitispossibletoemployastandardizedbearingofthe rightsizetype,theadvantagesofsuchspecialistresearchcan berealized.

E. Rack and Pinion arrangement:

The block, which holds the rack and pinion, is the crucial componentoftheapparatus.Thelinearmotionischanged into rotating motion by this block. Rotary motion is convertedintolinearmotionusinga rackandpiniongear arrangement. The line of action is perpendicular to the pinion,andtherack isa pieceofa gearwithinfinitepitch diameter.



Theprimaryissuewehadwasdecidingwhatkind ofmaterialtouse.Afterafewfailures,wecameto the conclusion that low weight and high strength materialshouldbeused.

 Thewheelchair'sbase'sframe'scapacitytosupport aheavybody.

 Thestretcher'sstructuralstrength.

 Howmanyconnections.

 Settingthemechanisminplace.

 Appropriate spacing to allow for design changes madeduringdevelopment.

 Mountingwheels.

 awheelchairtostretcherlockingsystem.

 Hingesandjoints.

B. DESIGN CALCULATION

MaterialUsedforDevelopment

1) M.S.hollowbaroftotallength15m

2) M.S.hollowbarofdiameter20mm

3) M.S.Lshape1”oflength6m

4) GACoatedM.Ssheetof2mmthickness3*(50*50).

5) M.S.Plateof2mm

6) Boltandnutof10mmdiameterand2inches’length

7) Caster–6pieces

8) OnepairofWheelsofdiameter69cm

9) Sponge(foam)

10) Leathercover

Load calculations

 Load on the wheels

WeightofBody=35kg

Weight of Body (Newton)=343.43N

WeightoftheHuman=120kg=1177.20N

WeightofRack&Pinion=3.4kg=33.354NForce =[343.43+33.354+1177.20]=1553.904N

Forceoneachwheel

ForceF1=F2=Force/4=1553.904/4=388.474N

 Load on Back Rest

 Link inclination = 20

egree Human weight = 40 kg

Weightoftheframe=10Kg

Force=(40+9.3)*9.81=483.63N

Forceactual=F*sin20=263N

 Load on Leg Rest Link inclination= 10 degree Human weight = 15kg Weight of the frame–10kg

Force=(40+10)M*9.81=490.5N

Forceactual=266.8254N

C. StressCalculation

 Stress on front casters

diameter(d1)=10mm

 Bending stressσb=My /I

Moment=Ff1*(L/2)=388.474*20=7769.48N.mm

Y=d1/2=5mm

I=( ) =490.8739mm4

σb=79.13927N/mm2

 Shearstress

τ=

Torque(T)=FF1*(L/2)=388.474*20=7769.48N.mm

R=d1/2=5mm

J=( ) =981.7478mm4

τ=39.56N/mm2

 Stress on rear wheel

Rearwheelshaftdiameter(d2)=10mm

 Bending stressσb=My/I Moment=Ff1*(L/2)=388.474*50=19423.7N.mm

Y=d1/2=5mm

I=( ) =490.8739mm4

σb=197.848N/mm2

 Shearstress

τ=

Torque(T)=FF2*(L/2)=388.474N *50

=19423.7N.mm

R=d2/2=5mm

J=( ) =981.7478mm4

τ=98.92N/mm2

D. Factor of Safety

F.O.S.= = =2.52

4. RESULTS AND DISCUSSIONS

The Traditional wheelchair and cum stretchersare pricey andhaveseveralflaws.Thewheelchairthatisavailablelacks astretcheroption.Therefore,thisnewformofwheelchair cumstretcheriscreatedtoaddressalloftheselimitations. The following is a list of the benefits of this design over traditionalwheelchairs.

 Detachablestretcherissupplied,providingcomfort whileshiftingthepatientfromonebedtoanother. •Easymaintenancemakesitmoreeffective.

 Thisdesigniseasytoconstruct;•Thebasecanbe utilizedasachairevenafterdetaching.

 Thestretcher'sadditionalwheelsmakeiteasierto useasatrolley.

 Compared to the market model, this one is less expensive.

5. CONCLUSIONS

Themechanismwasinventedanddesignedtolessenhuman weariness.Today,wheelchairsareseenasbothamode of transportation and a chance for its users to exhibit their uniquepersonalities.enablingthenurse'sassistanttohandle thepatientmoreeasilyinserioussituations.Transferringa patientfromabedtoawheelchairfromonelocationtothe hospital or another becomes highly challenging for the nursingstaff and the patientalike.Stressiscreatedin the patient'sbodyaswellasthenursingstaffasaresultofthe transitionfrombedtowheelchairorviceversa.Bycreatinga newdesignforthestretcherandwheelchairthatincludesa detachablestretcherthatcanbeoperatedeasilyandusedas a trolley when necessary, the aforementioned issues that arise when a patient is transferring from a bed to a wheelchaircanbeeliminated.Althoughthisdesignmaycost alittlemorethanastandardwheelchair,ithasmanymore functionsthatcanbenefitboththepatientandthenursing staff.Additionally,weareawarethatthereismuchroomfor improvementinthefuture.

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