نوع مقاله : مقاله کامل پژوهشی

نویسندگان

1 فارغ‌التحصیل دکتری، هسته‌ی علمی سامانه‌های پشتیبان در توسعه‌ی سلامت، دانشگاه یزد، یزد، ایران

2 استادیار، هسته‌ی علمی سامانه‌های پشتیبان در توسعه‌ی سلامت / گروه مهندسی مکانیک، دانشکده‌ی فنی و مهندسی، دانشگاه یزد، یزد، ایران

10.22041/ijbme.2020.121521.1568

چکیده

مرز تعادل روشی برای سنجش تعادل پویا در کلینیک و آزمایشگاه است که تحت تاثیر موقعیت و سرعت خطی مرکز جرم بدن قرار دارد. در این مطالعه عامل تعادل از طریق روش مرز تعادل محاسبه شده و از آن به عنوان تابع هزینه جهت برنامه­ریزی مسیر حرکت برخاستن استفاده شده است. برای محاسبه­ی کینماتیک حرکت، از نمای ساجیتال حرکت برخاستن 10 مرد جوان و سالم فیلم‌برداری شده و یک مدل دوبعدی و چهار سگمنتی بر اساس معادلات حرکت، برای محاسبه­ی موقعیت مرکز جرم، گشتاور مفاصل و انجام فرایند بهینه­سازی تعریف شده است. پس از محاسبه­ی مسیر تعادل آزمودنی­ها با استفاده از روش مرز تعادل، انتگرال زمانی مسیر تعادل (C1)، مقدار حداکثر و حداقل تعادل (C2) و انتگرال زمانی مربع مسیر تعادل (C3) به عنوان توابع هزینه تعریف شده است تا توسط الگوریتم ژنتیک به حداقل برسد. برای بررسی کیفیت مسیر پیش­بینی شده توسط مدل و مقایسه­ی آن با الگوی­ آزمودنی­ها نیز از خطای جذر میانگین مربعات استفاده شده است. طبق نتایج این پژوهش، مدلی که با استفاده از تابع هزینه­ی C3 بهینه­سازی شده، الگوی حرکتی آزمودنی­ها را به ترتیب با 19% و 40% خطای کم‌تر نسبت به C1 و C2 پیش­بینی کرده است. با این وجود پیش­بینی دقیق حرکت برخاستن توسط هیچ­یک از مدل­های پیشنهادی ارائه نشده است. در نهایت می­توان نتیجه گرفت که استفاده از تابع هزینه­ی مرز تعادل به تنهایی، انتخاب مناسبی برای برنامه­ریزی حرکات تمام بدن نمی‌باشد.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Optimization of Dynamic Stability Factor to Plan the Trajectory of Sit to Stand Movement

نویسندگان [English]

  • Mostafa Haj Lotfalian 1
  • Mohammad Hadi Honarvar 2

1 Ph.D., Center of Excellence for Support Systems in Health Development, Yazd University, Yazd, Iran

2 Assistant Professor, Center of Excellence for Support Systems in Health Development / Faculty of Mechanical Engineering, Yazd University, Yazd, Iran

چکیده [English]

Margin of stability is a method to assess the dynamic stability in the clinic and laboratory, which is influenced by position and linear velocity of the center of mass (CoM). In this study, the stability factor was calculated by the margin of stability (MoS) method and was used as a cost function to plan movement trajectory of sit to stand. 10 healthy young men were selected in this study and their sit to stand movement were filmed by Optitrack motion capture system. A two-dimensional and four-segment model was defined based on the governing equations of motion to calculate position of CoM, joints torque and using that in optimization process. After calculating the subject’s stability factor by MoS method, the time integral of MoS (C1), the maximum and minimum of MoS (C2) and the time integral of the square of MoS (C3) were defined as the cost functions. genetic algorithm was used to find the optimal model. To determine the quality of predicted trajectories and compare it with the subject’s pattern, root mean square error (RMSE) was used. According to the results of this study, a model which was optimized by C3, predicted the movement trajectory of subjects with 19 and 40 percent less error than C1 and C2 respectively.Nevertheless, none of the models could correctly reconstruct the subjects’ movement trajectory. In a nutshell, using MoS exclusively as a cost function, is not a good choice to predict and plane the trajectory of whole-body movements.

کلیدواژه‌ها [English]

  • Dynamic stability
  • Margin of Stability
  • Movement Trajectory
  • Sit to Stand
[1]   E.A. Wikstrom, M.D. Tillman, A.N. Smith, P.A. Borsa, “A new force-plate technology measure of dynamic postural stability: the dynamic postural stability index,” J Athl Train., vol. 40(4), pp. 305-309, 2005.
[2]   R.W. Sattin, “Falls among older persons: a public health perspective,” Annu Rev Publ Health., vol. 13(1), pp. 489-508, 1992.
[3]   M.M. Gross, P.J. Stevenson, S.L. Charette, G. Pyka, R. Marcus, “Effect of muscle strength and movement speed on the biomechanics of rising from a chair in healthy elderly and young women, ” Gait Posture., vol. 31; 8(3), pp. 175-185, 1998.
[4]   A. Shumway-Cook, M.H. Woollacott, “Motor control: theory and practical applications,” Lippincott Williams & Wilkins. Baltimore, MD.1995.
[5]   D.A. Winter, “ABC (anatomy, biomechanics and control) of balance during standing and walking,” Waterloo Biomechanics. Waterloo, Canada. 1995.
[6]   A.L. Hof, M.G. Gazendam, W.E. Sinke, “The condition for dynamic stability,” J Biomech., vol. 31; 38(1), pp. 1-8, 2005.
[7]   P. Sardain, G. Bessonnet, “Forces acting on a biped robot. Center of pressure-zero moment point,” IEEE Transactions on Systems, Man, and Cybernetics-Part A: Systems and Humans, vol. 34(5), pp. 630-637, 2004.
[8]   M. Fujimoto, L.S Chou, "Dynamic balance control during sit-to-stand movement: an examination with the center of mass acceleration." J Biomech, vol. 45(3), pp. 543-548, 2020.
[9]   A. Tarun, A. Oates, K. Lynd, K.E. Musselman, "Current state of balance assessment during transferring, sitting, standing and walking activities for the spinal cord injured population: A systematic review," J Spinal Cord Med, vol. 43(1), pp. 10-23, 2020.
[10]J. Nishii, Y. Taniai, “Evaluation of trajectory planning models for arm-reaching movements based on energy cost,” Neural Comput., vol. 21, pp. 2634-2647, 2009.
[11]J. Friedman, T. Flash, “Trajectory of the index finger during grasping,” Exp Brain Res., vol. 196, pp. 497-509, 2009.
[12]A. Biess, D.G. Liebermann, T. Flash, “A computational model for redundant human three-dimensional pointing movements: inte­gration of independent spatial and temporal motor plans simpli­fies movement dynamics,” J Neurosci., vol. 27, pp. 13045–13064, 2007.
[13]T. Flash, N. Hogan, “The coordination of arm movements: an experimentally confirmed mathematical model,” J Neurosci., vol. 1; 5(7), pp. 1688-1703, 1985.
[14]J. Kuželički, M. Žefran, H. Burger, T Bajd, “Synthesis of standing-up trajectories using dynamic optimization,” Gait Posture., vol. 21(1), pp. 1-11, 2005.
[15]M. Sadeghi, M. Andani, F. Bahrami, M. Parnianpour, “Trajectory of human movement during sit to stand: a new modeling approach based on movement decomposition and multi-phase cost function,” Exp Brain Res., vol. 229(2), pp. 221-234, 2013. 
[16]M. Hajlotfalian, A. Redaei, H. Sadeghi. “Biomechanical modeling of selected methods of load carriage to improve military capabilities of troops,” J Sport Biomech.  Accepted, 2016. (Persian).
[17]V. Bonnet, C. Mazzà, P. Fraisse, A. Cappozzo, “An optimization algorithm for joint mechanics estimate using inertial measurement unit data during a squat task, ” In Engineering in Medicine and Biology Society, Annual International Conference of the IEEE, pp. 3488-3491, 2011.
[18]A. KhazeniFard, F. Bahrami, M.E. Andani, M.N. Ahmadabadi, “An energy efficient gait trajectory planning algorithm for a seven linked biped robot using movement elements,” Iranian Conference on Electrical Engineering, pp. 1006-1011, 2015.
[19]M. Termeh, Mahdie, A. Ghanbarzadeh, M.H. Honarvar, K. Heidari Shirazi, "Dynamic balance Evaluation of the Seven-link Model in Single Support Phase of Walking based on probability of realization," Iran J Biomed Eng, vol. 13(4), pp. 375-387, 2020.
[20]D.A. Winter, “Biomechanics and Motor Control of Human Movement,” (2nd Edition Ed.), John Wiley and Sons Inc, pp. 82-107. 2009.
[21]M. Galli, M. Crivellini, F. Sibella, A. Montesano, P. Bertocco, C. Parisio. “Sit-to-stand movement analysis in obese subjects,” Int J Obes, vol. 24, pp. 1488–1492, 2000.
[22]M.R. Yeadon, M.A. King, C. Wilson, “Modeling the maximum voluntary joint torque/angular velocity relationship in human movement,” J Biomech, vol. 39, pp. 476–482, 2006.
[23]Y. Xiang, J.S. Arora, K. Abdel-Malek, “Physics-based modeling and simulation of human walking: a review of optimization-based and other approaches,” Struct Multidiscip O., vol. 42(1), pp. 1-23, 2010.
[24]M. Parnianpour, J.L. Wang, A. Shirazi-Adl, B. Khayatian, G. Lafferriere, “A computational method for simulation of trunk motion: towards a theoretical based quantitative assessment of trunk per­formance,” Biomed Eng., vol. 11, pp. 27–38, 1999.
[25]M.G. Pandy, B.A. Garner, F.C. Anderson, “Optimal control of non-ballistic muscular movements: a constraint performance criterion for rising from a chair,” J Biomech., vol. 117, pp. 15-25, 1995.
[26]D.A. Neumann. “Kinesiology of the musculoskeletal system-e-book: foundations for rehabilitation”. Elsevier Health Sciences, 2013.
[27]M.H. Honarvar, M. Nakashima. “A new measure for upright stability,” J Biomech., vol. 22; 47(2), pp. 560-567, 2014.