Vol 6, No 2 (2015) > Industrial Engineering >

Optimization and Improvement of Gas Spring Design in An Energy Storing Prosthetic Knee

Cucuk Nur Rosyidi, Rahmaniyah Dwi Astuti, Ilham Priadythama



In this
research, an optimization and improvement of gas spring design is discussed.
The gas spring is used as a suspension component of an energy storing
prosthetic knee. The gas spring replaces the quadricep muscles of transfemoral
amputee. A deterministic and a stochastic optimization is proposed in this
research. Both models are used to determine the optimal design variables of the
gas spring: cylinder diameter, cylinder length, extension stroke, and
compression stroke. The optimal design variables resulted from the deterministic
optimization model must be further analyzed to determine the effect of its
variation to the objective function. Monte Carlo simulation is used to
determine the effect of such variation and making improvement when necessary.
Process capability index (Cp) is used as a criteria to make such improvement
considering the contribution to variation of design variables to the objective
function. Stochastic optimization is proposed to find the optimal design
variables by taking into consideration the randomness of its parameters. The
objective function of the stochastic optimization is to maximize the capability
process. Both Monte Carlo simulation and stochastic optimization was solved
using Oracle Crystal Ball Software. From the simulation, the reduction of
compression stroke and extension stroke standard deviations resulted in 30%
improvement of energy storage standard deviation. The Cp is also improved about
70% from 0.99 to 1.44.  The stochastic
optimization resulted in extension stroke and compression stroke which are
shorter than deterministic optimization with 1.25 process capabilty.


Keywords: gas spring, improvement , stochastic optimization, Monte Carlo simulation

Full PDF Download


Arora J. S., (2004). Introduction to Optimum Design Second Edition, Elsevier Academic Press.

Azarm, S., dan Papalambros, P., (1982). An Interactive Design Procedure for Optimization of Helical Compression Springs, Research Report No. UM-MEAM-82-7.

Cherry, M. S., Choi, D. J., Deng, K. J., Kota, S., dan Ferris, D. P., Design and Fabrication of An Elastic Knee Orthosis-Preliminary Results, Proceedings of International Design Engineering Technical Conferences & Computers and Information in Engineering Conference, Philadelphia, USA.

Bergman, B., Demare, J., Loren, S., and Svensson, T., Robust Design Methodology for Reliability, John Wiley & Sons Limited, 2009.

Choi, S-K., Grandhi, R. V., and Canfield, R. A., Reliability-Based Structural Design, Springer-Verlag London Limited, 2007.

Cortesi, R. (2011), Gas Cylinder Spring. Available at http://roger-cortesi.com/ideas/public/gasspring.html. [12 March 2012].

Dictactor. Push Type Gas Springs. 2012. Dictactor Technik GMBH: Germany.

Delaney, K. D. and Phelan, P., Design Improvement ussing Process Capability Data, Journal of Materials Processing Technology, 209, pp. 619-624.

Haberman, A., (2008). Mechanical Properties of Dynamic Energy Return Prosthetic Feet, Master Thesis Queens University Kingston Ontario, Canada.

Hasegawa, H., Okaichi, A., Ikoma, M., dan Nishiwaki, F.(2002), A Study of A Linear Compressor with A Gas Spring, International Compressor Engineering Conference, School of Machenical Engineering Purdue University.

Kalaidjieva, M., Milusheva, S., dan Karastanev, S., (2009). Calculation and Design of Spring Elements for Ankle-Foot Orthosis, Proceedings of 11th National Congress on Theoretical and Applied Mechanics, Borovets, Bulgaria.

Krol, A., Wszolek, G., dan Czop, P. (2011), Optimization of Pneumatic Actuators with The Use of Design For Six Sigma Methoddology, Journal of Achievements in Materials and Manufacturing Engineering, Vol. 47, Issue 2,pp. 205-210.

Lift Support Technologies (2012). Gas Spring Principle, Available at http://www.lstechnologies.ca/principles.html. [24 April 2012].

Nelson II, S. A., Parkinson, M. B., dan Papalambros, P. Y., (2001). Multicriteria Optimization in Product Platform Design, Journal of Mechanical Design Vol. 123.

Nugraha, H. S., Jauhari, W. A., dan Rosyidi, C. N., (2011). Optimization for Helical Compression Spring of Lock Case with Maximum Reliability Criteria, Proceedings of Industrial Engineering and Service Science, Solo.

McQuail, K. and Reck, J., Prosthetic Knee Innovations: The XT9 ESPK and XT9 Air, University of Pittsburgh, Swanson School of Engineering, 2013.

Raychaudhuri, S., Introduction to Monte Carlo Simulation, Proceedings of the 2008 Winter Simulation Conference, pp. 91-99, 2008.

Rosyidi, C. N., Fitriawati, P., dan Astuti, R. D. (2012), Optimization Model for Gas Spring of Endoskeletal Prosthetic Leg with Maximum Energy Storage Criteria, Asia Pacific Industrial engineering and Management Systems Conference, Phuket, Thailand.

Savaresi, S. M., Poussot-Vassal, C., Spelta, C., Sename, O., dan Dugard, L. (2010), Semi-Active Suspension Control Design for Vehicles, Butterworth-Heinemann.

Stabilus (1995), Gas Spring Technical Information, Stabilus GmbH: Koblenz.

Symbiotechs USA (2006), XT9 Energy Storing Prosthetic Knee Technical Manual.

Tudose, L., and Jucan, D., (2007). Pareto Approach in Multi-objective Optimal Design of Helical Compression Springs, Fascicle of Management and Technological Engineering Volume VI (XVI, pp. 991-998.

Tudose, L., Morariu-Gligor, R. M., dan Haragas, S., (2009), Optimal Design of Helical Compression Springs from Tamping Rammers, Proceedings of The 2nd International Conference Advanced Engineering in Mechanical Systems, pp. 297-284.

Uhrmeister, B. (2000), Optimization of the Passive Shock Absorber of A Military Aircraft Symposium on “Active Control Technology for Enhanced Performance Operational Capabilities of Military Aircraft, Land Vehicles and Sea Vehicles”,Braunschweig, Germany.

Ultahar, A. (2011). Verifikasi Rancangan Prosthetic Knee Joint dengan Sistem Energy Storing bagi Penyandang Cacat Amputasi Trasfemoral. Skripsi S1 Jurusan Teknik Industri Universitas Sebelas Maret Surakarta.