DESIGN AND MANUFACTURING OF A SLIDING TABLE FOR A SIX AXIS SPINE TESTING MACHINE

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1 Volume 118 No , ISSN: (printed version); ISSN: (on-line version) url: ijpam.eu DESIGN AND MANUFACTURING OF A SLIDING TABLE FOR A SIX AXIS SPINE TESTING MACHINE 1 P.Susai Manickam, 2 S.Balamurugan, 3 D.Raja, 4 A.Vinoth, 5 Deepak jude denny, 6 Venkata koushik 1 Research Scholar, SRM Institute of science and Technology, Kattankulathur, Chennai, 2 Research Scholar, SRM Institute of science and Technology Kattankulathur, Chennai, 3 Research Scholar, SRM Institute of science and Technology Kattankulathur, Chennai, 3 Research Scholar, SRM Institute of science and Technology Kattankulathur, Chennai, 4 U.G.Student, SRM Institute of science and Technology Kattankulathur, Chennai, 5 U.G.Student, SRM Institute of science and Technology Kattankulathur, Chennai. 1 susairaphah@gmail.com Abstract: The present model of sliding table is an active type and it needs to be replaced with a passive type to analyse certain parameters associated with bone segments. The scope of this work is to create a passive sliding table to replicate the translations of the spine. For the passive sliding table the load calculations were done and in order to stimulate the loading conditions we created a finite element model of the passive sliding table. The static loading conditions was 300 N. Keywords: Spine, Sliding table, and finite element method 1. Introduction The spine is made up of 33 individual vertebra that interlock with each other and it forms the spinal column. This spinal column provides the main support for our body, allowing us to stand upright, bend, and twist. Effective treatments for spinal injuries and disease is one of the challenges facing the field of orthopedics society today. The six-axis spine testing machine is equipped with a active sliding table to replicate the translation of the spine the active table should be replaced as a passive table. The passive table should slide in two directions X and Z direction. During the flexion and extension, it should slide in x direction and for lateral bending it should slide on z direction. To simulate in x direction we considered two configurations namely slider in the initial position shown in the figure -1 of the table and the slider in the final position shown in the figure-2. The unique morphology of the spine segment provides the highest mobility and has challenged surgeons and clinicians to develop safe surgery protocol and rigid fusion constructs for the treatment of degenerative diseases and disc replacement. [3,4].Unconstrained translations are permitted by using linear bearing guide rails [5,6]. Figure 1. Six axis spine testing machine COURTESY: ttype/test-systems/simulation-systems/biomedicalwear-simulation/spine/index.htm COURTESY: cuments/library/dev_ pdf Figure 2. Six axis spine testing machine. 815

2 The first step of design involved designing of each component of the passive sliding table which includes from the kinematic arrangement. The next important and crucial step was to stimulate the components for the testing conditions under which they are supposed to be used i.e. the amount of load and moment applied on them at different configuration. Based on the analysis results which were done by assigning different material properties to every component the suitable material were selected like hard carbon steel for the rails; aluminium for base plates, specimen holding cup and base cup. After the above steps were completed based on the results obtained the passive sliding table was made but the most important factor to be determined was to whether the table was working as per the required specifications. The x and z direction are used to replicate the pure continuous moments in flexion extension, lateral bending, and axial rotation. [1]. In the disc replacement studies the sliding table can be used [2]. Figure 3. Sliding Table (Passive) 2. Materials and Methods The methodology followed for the building of the passive sliding table are as mentioned above and all these steps took place in a sequential order to ensure that the passive sliding table works perfectly.the most important part of the sliding table was to implement a design which can perfectly stimulate the translation of the spine segment along two mutually perpendicular axis, at the same time it should be able to withstand high loads so that factors like deflection will not tamper with the experimental results. Different designs were pitched and the final design was decided based on the proposed design of the other components. The first step of design involves designing of each and every component of the passive sliding table which includes from the kinematic arrangement to design of each and every component. The next important and crucial step was to stimulate the components for the testing conditions under which they are supposed to be used i.e. the amount of load and moment applied on them at different configuration. Based on the analysis results which were done by assigning different material properties to every component the suitable material were selected like hard carbon steel for the rails; aluminium for base plates, specimen holding cup and base cup. After the above steps were completed based on the results. obtained the passive sliding table was made but the most important factor to be determined was to whether the table was working as per the required specifications. The modelling of the components was done using CATIA V6 and the meshing and analysis was carried out using Ansys workbench Figure 4. Configuration -1 The intermediate plates used for joining mechanism were supposed to be light weight so aluminium plates were used. The rails are supposed to withstand high loads as well easy to machine so high carbon steel were used. The base cup and specimen holding cup are supposed to be of very light weight as well as strong enough the bear the weight of the entire model and load applied on it and so aluminium were used. Figure 5. Configuration

3 3. Result and Discussion The loading condition applied at the initial position is around 300 N and at the final position is 300 N. The bottom cup is fixed and a compression force of 300 N is applied at the top of the cup. In the configuration- 1 the specimen will be kept initial position and Von mises stress distribution across the whole structure is studied. In the initial position the stress distribute on was around N/mm 2 are shown in figure-6. Figure 8. Comparison of Configuration 1 and Configuration -2 In the comparison of Configuration 1 and 2 we concluded that the x and z table stresses are within the limits and it can replicate the motion of the spine. 4. Conclusion Figure 6. Von Mises stress for configuration 1 The configuration-2 the specimen will be in the end position of flexion, extension or lateral bending. In the final position the stress distribution was around N/mm 2 are shown in the figure-7. The existing sliding table was an active sliding table and it could not replicate the translation of the spine. So in order to overcome the existing problem the design of the passive table was done. The loading applied to the table was around 300 N and during the load the sliding table should replicate the motion of the spine at the same time the sliding table should not go for a deflection. References Figure 7. Von Mises stress for configuration 2 [1] Nicole Kallemeyn, Anup Gandhi, Swathi Kode, Kiran Shivana, Joseph Smucker, Nicole Grosland, (2010), Validation of a C2-C7 cervical spine finite element model using specimen-specific flexibility data, Elsevier, Medical Engineering and physics [2] Vijay K Goel, Ahmad Faizan, Vivek Palepu, Sanghita Bhattacharya, (2012), Parameters that effect spine biomechanics following cervical disc replacement, Springer,21 (Suppl5):S688-S699 [3] Ronald A. Lehman, Anton E. Dimitriev, Kevin W. Wilson, (2012), Biomechanical analysis of the C2 intralaminar fixation technique using a cross-link and offset connector for an unstable atlantoaxial joint, The spine journal Elsevier,Volume 12, [4] Anton E. Dmitriev, Norman W. Gill, Timothy R. Kuklo, Michael K. Rosner, (2008), Effect of multilevel lumbar disc arthroplasty on the operativeand adjacent-level kinematics and intradiscal pressures: 817

4 an in vitro human cadaveric assessment, The Spine Journal Elsevier, Volume 8, [5] Bryan W. Cunningham, (2004), Basic scientific considerations in total disc arthroplasty, The Spine Journal Elsevier, Volume 4, 219S-230S [6] Bryan W. C (2010)unningham, Nianbin Hu, Candace M. Zorn, Paul C. McAfee, Biomechanical comparison of single and two-level cervical arthroplastyversus arthrodesis: effect on adjacent-level spinal kinematics, The Spine Journal Elsevier, Volume 10, [7] T.Padmapriya and V.Saminadan, Utility based Vertical Handoff Decision Model for LTE-A networks, International Journal of Computer Science and Information Security, ISSN , vol.14, no.11, November [8] S.V.Manikanthan and V.Rama Optimal Performance of Key Predistribution Protocol In Wireless Sensor Networks International Innovative Research Journal of Engineering and Technology,ISSN NO: ,Vol-2,Issue Special March [9] Rajesh, M., and J. M. Gnanasekar. & quot; Congestion Control Using AODV Protocol Scheme For Wireless AD-HOC Network.& quot; Advances in Computer Science and Engineering 16.1/2 (2016): 19. [10] N.Prathima, K.Hari Kishore, Design of a Low Power and High Performance Digital Multiplier Using a Novel 8T Adder, International Journal of Engineering Research and Applications, ISSN: , Vol. 3, Issue.1, Jan-Feb.,

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