1408 P a g e FOUR BAR MECHANISM

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1 Applications (IJERA) ISSN: Vol., Issue 5, Septeber- October 01, pp Design, Synthesis & Siulation Of Four Bar Mechanis For Guiing Wheel For Clibing Rahul R.Gurpue M.Tech Stuent Dr.R.D.Ashkhekar Dean K.D.K.C.E,nagpur ABSTRACT In the fiel of proviing obility for the elerly an isable the aspect of ealing with stairs continues largely unresolve. This paper focuses on presenting the evelopent of a stairclibing wheelchair echanis with high single step capability. The echanis is base on all four wheel clusters connecte to the base (chair) via powere linkages so as to perit the forwar irection, an high single step functionality. Also the big task is to calculate the iensions of four bar echanis as per require task,hence with the help of chebechevs equation an frauenstein s equation,several bunch of solution being obtaine epening on function on which siulation is carrie out but only one can support to require task i.e. to clib the stair of 0 height with respect to reference skeleton frae with respect to which final siulation being carrie out. INTRODUCTION As we enter the secon illenniu since the tie of Christ there is an increasing in fulness of the nee to focus technology on helping people. One specific area of nee is that of proviing increase freeo in ters of obility forthe elerly or isable. The reasons being to provie an optiu quality of life for the isable or elerly, an to reuce the loa on care workers, the two aspects being closely linke by thec onscious sense of being a buren. Autonoy in the area of obility has always been highly value, but is soe tie sipaire by soe for of isability. In any cases this results in reliance on soe for of external transport echanis. In this regar traitional wheelchairs an powere wheelchairscontinue to play a vital role. However wheelchairs to ate provie a high level of obility only inartificial or barrier free environents. That is there reains a significant gap between theobstacle negotiating ability of a wheelchair an that of the average able boie person. This aspect is perhaps ost apparent when consiering stairclibing. While oern architecture an new policies continue to ake newly built areas as accessible as possible to persons with awie variety of isabilities steps will always be a reality in the real worl.hence in the fiel of proviing obility for the elerly an isable the aspect of ealing with stairs continues largely unresolve. This thesis focuses on presenting the evelopent of a stair-clibing wheelchair echanis with high single step capability.the echanis is base on all four wheel clusters connecte to the base (chair) via powere linkages so as to perit the forwar irection, an high single step functionality for. Priary consierations were inherent stability, provision of a echanis that is physically no larger than a stanar powere wheelchair, aesthetics an being base on reaily available low cost coponents. Also the big task is to all acuate the iensions of four bar echanis as per require task,hence with the help of chbechevs equation an frauensteinsequationin which several bunch of solution being obtain epening on function on ehich siulation is carrie out but only one can support to require task i.e. to clib the stair of 0 height with respect to reference skeleton frae with respect to which final siulation being carrie out.alsocoparision carrie out epening upon existing techniques use for task previously. It escribes a esign of a echanis that ais a wheel to clib steps. The propose four-bar linkage can be installe on each wheel of a vehicle, which therefore can be capable to clib stairs with suitable cofortable otion. A straight-line trajectory for the centre of a wheelis ensure through an easily controlle otion, an the copactness of the echanisesign akes it suitable for staircase clibing wheelchairs for aiing people with isability FOUR BAR MECHANISM Out of which we will go for Frauenstein s equation because of avantage that all values are being arrange in analytical anner an also 1408 P a g e

2 Applications (IJERA) ISSN: Vol., Issue 5, Septeber- October 01, pp calculation are being arrange siple forulation hence will leas towars accuracy as copare to other ethos as that of graphical which will leas to an huge error in case of sall istakes. To solve resolving all forcces in x-irection & y- irection on aing both we have cos θ 1.cos θ 1 +sinθ 1.sin θ = k 1 cosθ 1 - k cos θ +k 3 cos( θ -θ 1 ) = k 1 cos θ 1 - k cos θ 1 + k 3 Where, k 1 = r 1 / r, k = r 1 / r 4, k 3 = r - r 3 + r 4 + r 1 / r.r 4 FORMULATION OF PROBLEM: Here we have to finalize iensions of four bar echanis,taking into consieration 3 precision point etho an fraueinsteins equation following proceure for ifferent functions such as y=1/x,y=x,y=x 3,y=In X, Y=log x,y=e x,y=sin x,y=cos x, y=tan x are ifferent types of functions being use an calculation are as follows 1)0<x<360 )Δθ=360 0, ΔФ=10 0 3)Фs=0 0,θs=0 0 4)Bychebchev spacing ΔXj=ΔX/(1-cos( (j- 1)/n)) 5) θj=δθ/δx (Xj-X1) 6) Фj=ΔФ/ΔY (Yj-Y1) 7)ByFrauensteins equation K 1 cosθ +K cosф+k 3 =- cos(θ-ф) 8) Calculate K 1,K,K 3 9)Assue any one linklength Z 1 =0 10)K 1 =Z 1 /Z 4, K =-Z 1 /Z 4, K3=Z 3 -Z -Z 1 - Z 4 /*Z *Z 4 CALCULATIONS FOR DIFFERENT FUNCTIONS: 3 precision point an frauensteins equation 0 0 <x<360 0 Δθ=360 0, ΔФ=10 0 Θs=0 0,Фs=0 0 1)For Function Y=X 5 By chebyshev spacing forula ΔXj=ΔX/*(1-cos( (j-1)/n)) ΔX=(Xn+1)-(X0)=360-0=360 For j=3.5,4.5,5.5 ΔX1=360/*(1-cos( (*3.5-1)/*3))=35 ΔX=360/*(1-cos( (*4.5-1)/*3))=45 ΔX1=360/*(1-cos( (*5.5-1)/*3))=55 Now, X 0 =0 Y 0 = X 1 =6 Y 1 =5.89*10 11 X =61 Y =1.1*10 1 X 3 =306 Y 3 =.68*10 1 X 4 =360 Y 4 =6.04*10 1 θj=δθ/δx(xj-x1) Фj=ΔФ/ΔY(Yj-Y1) Therefor, θ1=360/360*(0-0)=0 Ф1=10/6.04*10 1 ( - )=0 θ=360/360*(61-6)=35 Ф=10/6.04*10 1 *(1.1* *10 11 )= 50 θ3=360/360*(61-06)=45 Ф3=10/6.04*10 1 *(.68* *10 1 )= 55 θ4=360/360*( )=55 Ф4=10/6.04*10 1 *(6.04* *10 1 )= 65 Now by Fraueinsteins equations K 1 Cosθ 1 +K CosФ 1 +K 3 =-Cos(θ 1 -Ф 1 ) 0.81K 1-0.5K +K 3 = K K +K 3 = K K +K 3 =-0.96 Therefore K1=0.33,K=-0.37,K3=1.08 We have K 1 =Z 1 /Z 4 K =-Z 1 /Z K 3 =Z 3 -Z -Z 1 -Z 4 /*Z *Z 4 Assue Z 1 =0 Then Z 4 =7.9,Z=9,Z3=195 Basic link iensions on coparision for ifferent function as Y=X 5, Y=X 3 Y=X,Y=1/X Function Z1 Z Z3 Z4 Result Y=X Y=X Y=X Y=1/X siulae 536 Can be siulate 80.9 Can be siulate SIMULATION 1)Ientify the proble: First of all to calculate iensions require as per nee i.e. to forulate an calculate iension of echanis to clib the stair of height about 0 an calulation as shown in the syntesis forulation an table with forulation as follow Can siulate be 1409 P a g e

3 Applications (IJERA) ISSN: Vol., Issue 5, Septeber- October 01, pp Translate these conceptual oels to siulation software acceptable for. ) Forulate the proble: With following steps we can forulate the proble 1)0<x<360 )Δθ=360 0, ΔФ=10 0 3)Фs=0 0,θs=0 0 4)Bychebchev spacing ΔXj=ΔX/(1-cos( (j- 1)/n)) 5) θj=δθ/δx (Xj-X1) 6) Фj=ΔФ/ΔY (Yj-Y1) 7)ByFrauensteins equation K 1 cosθ +K cosф+k 3 =- cos(θ-ф) 8) Calculate K 1,K,K 3 9)Assue any one linklength Z 1 =0 10)K 1 =Z 1 /Z 4, K =-Z 1 /Z 4, K3=Z 3 -Z -Z 1 - Z 4 /*Z *Z 4 5) Valiate the oel: Copare the oel's perforance uner known conitions with the perforance of the real syste. 3) Collect an process real syste ata: Collect ata on syste specifications (e.g., banwith fora counication network), input variables, as well as perforance of the existing syste. 4) Forulate an evelop a oel: Develop scheatics an network iagras of the syste (How o entities flow through the syste?) P a g e

4 Applications (IJERA) ISSN: Vol., Issue 5, Septeber- October 01, pp ) Establish experiental conitions for runs: Aress the question of obtaining accurate inforation an the ost inforation fro each run. Deterine if the syste is stationary (perforance easure oes not change over tie) or non-stationary (perforance easure changes over tie). 9) Recoen course of action 7) Perfor siulation runs: 8) Interpret an present results: 1411 P a g e

5 Applications (IJERA) ISSN: Vol., Issue 5, Septeber- October 01, pp RESULT AND CONCLUSION: By synthesis of four bar echanis by frauensteins equation an chebchevs equation, four bunches of iension being obtaine by conciering ifferent function as follows Basic link iensions on coparision Function Z1 Z Z3 Z4 Result Y=X siulae Y=X Can be siulate Y=X Can be siulate Y=1/X Can be siulate On which the siulation is being calculate out of which all iension can be siulate bue the calculation gor function Y=X 5 being selecte because it is only iension which woul folloe the skeleton igra require for siulation reaning will give the eviation as shown below an final assebly been prouce. REFERENCES [1] A. Gonzalez, E. Ottaviano, M. Ceccarelli (008 A Generalise Perforance On the kineaticfunctionallity of a four-bar base echanis for guiing wheels in clibing steps an obstacles publishe in a journal Mechanis an Machine Theory [] R.Morales, V.Feliu, Kineatic oel of a new staircase clibing Mechanical an Kineatic Design Methoology of a New Wheelchair with Aitional Capabilities in a Journal Robotic reasearch book eie by : Maki K. Habib 007. [3] A. Gonzalez, p. Pintao, kineatic oel of new staircase clibing wheelchair an its experiental valiation in athe international journal of robotics reaserch vol. no.9 [4] Rafael orales, Antino Gonzalez- Roriguez, Angel g. Gonzalez-Roriguez, university of Jaen spainin echanical synthesis for easy an fast operation in clibing an walking Robot. [5] R. Morales, V. Feliu, A. González, P.PintaoCoorinate Motion of a New Staircase Clibing Wheelchair with Increase Passenger Cofort. [6] Siulation of software for four bar function genrator echanis by Suwarna B. Torgal, K.Tripathi&N.K.Nagar [7] Mechanis Design By Eran &Senor. 141 P a g e