A New Knee Prosthesis Design Based on Human Lower Limb Cinematic Analysis

Transcription

1 Poceedings of the old Congess on Engineeing Vol III CE July - London U.K. New Knee Posthesis Design Based on Human Lowe Limb Cinematic nalysis Cistian Copilusi ihnea ain and Ligia Rusu bstact In this pape a human lowe limb cinematic analysis is ealized by using a computeized method with a flexible chaacte easy to implement onto compute. hough this method we obtain the genealized coodinates motion laws of the knee cinematic joint fom the equivalent model of the human lowe limb. hese laws ae useful fo a new human knee posthesis design. Index ems cinematic knee posthesis human lowe limb. I. INRODUCION NY eseaches have been developed diffeent methods fo study the human lowe limb cinematic [] [] [] []. he cinematic methods aim is to study diffeent motion types of the human lowe limb in ode to impove the athletes pefomances o to design new human lowe limb posthesis. he cinematic analysis of a mechanical model consists in solving two impotant poblems: cinematic diect poblem and cinematic invese poblem. In the cinematic diect poblem s fame the displacements fom cinematic joint ae known and it will be detemined the positions oientation speeds and acceleations of the mechanism elements o some chaacteistic points onto the analyzed mechanism. In the cinematic invese poblem the cinematic paametes fo some chaacteistic points motion ae known and it will be detemined the cinematic paametes of the cinematic joints elative motions. ith these in the cinematic analysis context we identify many poblems such as: - Positional poblem - peed poblem - cceleations poblem. Each of these poblems pesents a diect o invese aspect. II. HUN LOER LIB CINEIC NLYI he method used in this pape has a flexible chaacte and assues an inteface fo dynamic analysis especially fo finite element modeling of spatial and plana mobile mechanical systems []. Fo the cinematic analysis the cinematic model pesented in figue will be consideed. he cinematic model analysis will be pefomed only fo walking activity fo a single gait. he cinematic paametes vaiation laws wee obtained by pocessing with the PLE softwae aid the mathematical models which ae defining the human lowe limb expeimentally cinematic analysis. Fom a stuctual viewpoint the cinematic chain it consists in otation joints. anuscipt eceived ach 9 evised ach 9. his wok was suppoted in pat by the Roumanian. Depatment of Reseach unde Gant CNCI PNII RU PD 9 code: /... C. Copilusi is with the Faculty of echanics Univesity of Caiova. Calea Bucuesti no.. Romania (coesponding autho to povide phone: + cistache@yahoo.co.uk).. ain is with the Faculty of echanics Univesity of Caiova. Calea Bucuesti no.. Romania ( mih_main@yahoo.com). L. Rusu is with the Faculty of Educational Physics and pot. Univesity of Caiova. Bestei steet. Romania ( ligiausu@hotmail.com). Fig.. he cinematic model equivalent with the human lowe limb he i position vectos in the i efeence coodinate system ae: IBN: IN: -9 (Pint) IN: -9 (Online) CE

2 Poceedings of the old Congess on Engineeing Vol III CE July - London U.K. L L L L L L L L L. he connectivity ode will be:c x Position calculus he position vectos ae: x y z x y z x y z x y z x y z x y z x y z x y z () () () () () () () () (9) x y z () hee: L L L L L L L L L. he vecto has the following expession: () () Changing the vesos base at cossing fom a efeence coodinate system to anothe (intoducing the coodinate tansfomation matices): () () () () () () (9) () By analyzing the ()... () elations we obseve that: () () () Based on ()... () elations we identify the coodinates tansfomation matices fo each cinematic joints with i i 9 and i. Point: B C D E F G H and positions in appot with coodinate system bounded to the coxae bone will be identified though elations: CX CX B CX C () () () () () (9) () CX D CX E CX F () () () IBN: IN: -9 (Pint) IN: -9 (Online) CE

3 Poceedings of the old Congess on Engineeing Vol III CE July - London U.K. G CX CX H CX B. peed calculus e follow to detemine the point speed in appot with efeence system. Fo this we diffeentiate successively the ()... () elations but fo achieve this calculus is necessay to build the anti symmetic matices fo each joint like this fom: () () () i i i i with i j () i j j Fo this: () (9) () () IBN: IN: -9 (Pint) IN: -9 (Online) () () () () Fo each: B C D E F G H and point we obtain: v B v C v () () v D v E v F v G () (9) () () () CE

4 H v () v () C. cceleation calculus hese will be obtained by diffeentiating successively the ()... (). Fo and B we will obtain the acceleations fom () and () elations. imilaly we obtain the acceleations of the following points: C D E F G H. he acceleation fo point is given by () elation. a () B a () a () III. NUERICL PROCEING Fo the cinematic analysis we conside known the geometical elements. he calculus algoithm was elaboated with the PLE softwae s aid. he geometical elements dimensions ae: L = mm L = mm L =mm L = mm L = mm L = mm L = mm L = mm L = mm. he genealized coodinate system vaiations fom the joints equivalent to the human lowe limb ae pesented in the cinematic diagams (figues: and ). In figue the human locomotion system s D vitual model is pesented. his was designed by and simulated with the C NRN softwae s aid. Fo vitual simulation we follow the pocedues fom [] and we implement the motion laws esulted fom the analysis developed peviously (figues and ) on a human subject without locomotion disabilities. e mention that the motion laws wee pocessed fo each joint individually in such a manne that the vitual model can pefom a single gait in the walking activity. Poceedings of the old Congess on Engineeing Vol III CE July - London U.K. IBN: IN: -9 (Pint) IN: -9 (Online) CE

5 Poceedings of the old Congess on Engineeing Vol III CE July - London U.K. Fig.. q vaiation angle [degees] coesponding with the equivalent hip joint Fig. q vaiation angle [degees] coesponding with the equivalent foot joint Fig.. q vaiation angle [degees] coesponding with the equivalent knee joint Fig.. D model designed and simulated with C NRN Fig.. q vaiation angle [degees] coesponding with the equivalent ankle joint IV. CINEIC REUL PPLICION ONO KNEE PROHEI ECHNICL YE Based on cinematic motion laws imposed fo a knee posthesis mechanism we design a D vitual model of cam mechanism posthesis with the CI V R aid. his mechanism is simila with a one designed fo human ankle posthesis []. e integated the FEO YR---C shock absobe in the posthesis esistance stuctue which enables some axial adjustments with a view to establishing the posthesis alignment. Figue shows the new knee posthesis design. his is whee we identify -femu component -cilindical joint - cam followe - cam - tibia component - FEO shock absobe -aditional shock absobe mechanism. fte simulating the vitual model and validating the cam mechanism though calculation we executed and adapted this posthesis in accodance with an amputee's needs and suggestions. In figue we pesent an aspect fom the new posthesis expeimental tests which wee pefomed with II otion s aid. IBN: IN: -9 (Pint) IN: -9 (Online) CE

6 Poceedings of the old Congess on Engineeing Vol III CE July - London U.K. posthetic centes. he knee mechanism functionality validates the cinematic analysis of the human lowe limb. Fig.. Vitual model of the posthesis used in human knee disaticulations Fig. 9. he new posthesis flexion/extension angula displacement vaiation depending on time CKNOLEDGEN he eseach wok epoted hee was made possible by Gant CNCI UEFICU poject numbe PNII RU PD 9 code: /... Fig.. he new knee posthesis and an aspect fom the new posthesis expeimental tests achieved with II otion softwae V. CONCLUION Fo cinematic modeling we use a method which is based on simple matices fomalism with the possibility to implement on a compute pogam fo the diect o invese cinematic analysis. his method is valid fo plana and spatial cinematic mechanisms with possibility to study the cinematic paametes in the absolute o elative motion mode. Fo the mathematical models pocessing coesponding to the cinematic analysis a pogam unde PLE pogamming language was elaboated. It was elaboated a cinematic scheme fo the human lowe limb equivalent mechanism based on some specialty liteatue efeences but also with pope obsevations mainly fo knee joint. athematical model wee elaboated fo position speeds and acceleations detemination fo some inteest points used fo expeimental modeling accoding with a new posthesis design fo knee joint. he novelty element which assues the posthesis models design is epesented by cam mechanisms. Based on an expeimental cinematic analysis of these postheses by using II otion softwae the angula amplitude developed by this mechanism is appopiate with the one developed by a healthy human subject. o fo the human knee joint eplacement mechanism the angula amplitude fo walking activity was degees (figue 9) and the one developed by a healthy subject was degees [9] []. he posthesis pesented in this pape is cheap in compaison with the ones manufactued by the specialized REFERENCE [] R.. Kiss L. Kocsis and Z. Knoll. Joint kinematics and spatial tempoal paametes of gait measued by an ultasound-based system. ed. Eng. Phys. vol. pp.. []. Heyn R. E. ayagoitia. V. Nene and P. H. Veltink. he kinematics of the swing phase obtained fom acceleomete and gyoscope measuements. th Int. Conf. IEEE Engineeing in edicine and Biology ociety Bidging Disciplines fo Biomedicine 99. [] ohl G.. and Bobow J. E. Recusive ultibody Dynamics and ensitivity lgoithm fo Banched Kinematic Chains. E J. Dyn. yst. eas. Contol _ pp [] ndeson F. C. and Pandy. G. Dynamic Optimization of Human alking. J. Biomech. Eng. _ pp. 9. [] Dumitu N. Nanu G. Vintilă D. echanisms and mechanical tansmissions. oden and classical design techniques. Didactic pinting house IBN Buchaest. [] Dumitu N. agine. odelling bases in mechanical engineeing. Univesitaia pinting house IBN Caiova - Romania. [] Copiluşi C. Dumitu N. Rusu L. ain. Cam echanism Cinematic nalysis used in a Human nkle Posthesis tuctue. old Congess on Engineeing.. London U. K. pp. -. [] Copilusi C. Dumitu N. Rusu L. ain. Implementation of a cam mechanism in a new human ankle posthesis stuctue. D Intenational Confeence Vienna 9 pp. -. [9] Copilusi C. Reseaches egading some mechanical systems applicable in medicine. PhD. hesis Faculty of echanics Caiova - Romania 9. [] illiams. Biomechanics of human motion..b. aundes Co. Philadelphia and London. 99. [] Vucina. Hudec. Kinematics and foces in the above knee posthesis duing the stai climbing. cientific pape OR Bosnia. [] ang C-Y. E. Bobow J. E. Reinkensmeye D. J. Dynamic otion Planning fo the Design of Robotic Gait Rehabilitation Jounal of Biomechanical Engineeing. Vol... [] ang C-Y. E. Bobow J. E. and Reinkensmeye D. J. winging fom the Hip: Use of Dynamic otion Optimization in the Design of Robotic Gait Rehabilitation. IEEE Intenational Confeence on Robotics and utomation pp.. [] Dumitu N. Checiu. lthalabi Z. heoetical and Expeimental odelling of the Dynamic Response of the echanisms with Defomable Kinematics Elements IFo Besancon Fance.. [] Hooman Dejnabadi Bigitte. Jolles Emilio Casanova Pascal Fua Kamia minian Estimation and Visualization of agittal Kinematics of Lowe Limbs Oientation Using Body-Fixed ensos. IEEE ansactions On Biomedical Engineeing Vol. No. pp. 9. IBN: IN: -9 (Pint) IN: -9 (Online) CE