This paper presents the development and implementation of a pneumatic muscle actuator based on an idea proposed by a research group at the University of Warsaw. The muscle comprises a silicone rubber tube with plugs at the ends. The tube wall contains high-rigidity wires arranged parallel to the tube axis. Circular rings are present on the exterior of the tube. When air is introduced into the tube, the actuator becomes bulky and contracts. In order to establish a prediction model of muscle behavior, a finite element model was developed, and in this model, the Mooney-Rivlin formulation was implemented with two coefficients for rubber simulation and truss elements for the wires. Several prototypes were developed, and a test bench for the experimental characterization of muscle performance was set up. The results of comparison between prototype behavior and model prediction are presented. The finite element model can be used to design the actuator with different dimensions; hence, it was used to conduct a simulated test campaign to develop a quick actuator sizing procedure. Using dimensional analysis, few project parameters were identified on which the performance of the actuator depends. Through a complete simulation campaign using the finite element model, an abacus was constructed. It allows sizing the actuator as required based on the desired performances according to an established procedure.

1. [1] M. G. Antonelli, S. Alleva, P. Beomonte Zobel, and F. Durante, “A Methodology for the Development of an Active Ankle Prosthesis,” Int. J. of Mechanical Engineering and Technology, Vol.9, No.2, pp. 221-234, 2018.
2. [2] F. Durante, P. Beomonte Zobel, and T. Raparelli, “Development of an active orthosis for inferior limb with light structure,” Proc. of RAAD2017, July 21-23, Torino, Italy, 2012, pp. 783-791, 2012.
3. [3] N. Koceska, S. Koceski, F. Durante, P. Beomonte Zobel, and T. Raparelli, “Control architecture of a 10 DOF lower limbs exoskeleton for gait rehabilitation,” Int. J. of Advanced Robotic Systems, Vol.10, No.168, doi: 10.5772/55032, 2013.
4. [4] J. Fryman and B. Matthias, “Safety of Industrial Robots: From conventional to Collaborative Applications,” Proc. of ROBOTIK 2012, 7th Conf. on Robotics, May 21-22, Munich, Germany, 2012.
5. [5] A. Bicchi and G. Tonietti, “Fast and soft arm tactics: dealing with the safety-performance tradeoff in robot arms design and control,” IEEE Robotics and Automation, Vol.11, No.2, pp. 22-33, 2004.
6. [6] H. F. Schulte, “The characteristic of the McKibben artificial muscle,” National Academy of Sciences, National Research Council (Eds.), The Application of External Power in Prosthetics and Orthotics (Publication 874, Appendix H), Washington, DC: National Academy of Sciences, National Research Council, pp. 94-115, 1962.
7. [7] J. M. Winters, “Braided artificial muscles: mechanical properties and future uses in prosthetics/orthotics,” Proc. of the RESNA 13th annual conf., Washington, DC, June 15-20, pp. 173-174, RESNA Press, 1990.
8. [8] D. G. Caldwell, A. Razak, and M. J. Goodwin, “Braided pneumatic muscle actuators,” Proc. of the IFAC Conf. on intelligent autonomous vehicles, Southampton, April 18-21, pp. 507-512, Pergamon, 1993.
9. [9] C. P. Chou and B. Hannaford, “Measurement and modelling of McKibben pneumatic artificial muscles,” IEEE Trans. on Robotics and Automation, Vol.12, No.1, pp. 90-102, 1996.
10. [10] G. Belforte, G. Eula, A. Ivanov, T. Raparelli, and S. Sirolli, “Presentation of textile pneumatic muscle prototypes applied in an upper limb active suit experimental model,” The J. of Textile Institute, doi: 10.1080/00405000.2017.1368111, 2017.
11. [11] G. B. Immega, “ROMAC actuators for micro robots,” Proc. of micro robotics and teleoperators workshop, IEEE Robotics and Automation Council, Hyannis, MA, November 9-11, 1987.
12. [12] H. A. Baldwin, “Realizable models of muscle function,” Proc. of the first rock biomechanics symposium, New York, April 5-6, pp. 139-148, Springer, 1967.
13. [13] J. N. Marcinčin, J. Smrček, and J. Niznik, “Bioactuators – most efficient actuators for biomechanics,” Proc. of the 7th Int. IMEKO TC-13 on measurement in clinical medicine “Model Based Biomeasurement,” Stara Lesna, September 6-9, pp. 369-371, P. Kneppo and M. Tysler (Eds.), 1995.
14. [14] F. Daerden and D. Lefeber, “Pneumatic artificial muscles: actuators for robotics and automation,” European J. of Mechanical and Environmental Engineering, Vol.47, No.1, pp. 11-21, 2002.
15. [15] D. Villegas, M. Van Damme, B. Vanderborght, P. Beyl, and D. Lefeber, “Third-generation pleated pneumatic artificial muscle for robotic applications: development and comparison with McKibben muscle,” Advanced Robotics, Vol.26, No.11-12, pp. 1205-1227, 2012.
16. [16] T. Noritsugu, M. Takaiwa, and D. Sasaki, “Development of a pneumatic rubber artificial muscle for human support applications,” Proc. of the 9th Scandinavian int. conf. on fluid power, Linkoping, June 1-3, 2005.
17. [17] M. G. Antonelli, P. B. Zobel, P. Raimondi, T. Raparelli, and G. Costanzo, “An innovative brace with pneumatic thrusts for scoliosis treatment,” Int. J. of Design & Nature and Ecodynamics, Vol.5, No.4, pp. 1-14, 2010.
18. [18] G. Belforte, G. Eula, A. Ivanonv, and S. Sirolli, “Soft pneumatic actuators for rehabilitation,” Actuators, Vol.3, pp. 84-106, 2014.
19. [19] M. G. Antonelli, P. Beomonte Zobel, F. Durante, and F. Gaj, “Development and testing of a grasper for NOTES powered by variable stiffness pneumatic actuation,” Int. J. of Medical Robotics and Computer Assisted Surgery, doi: 10.1002/rcs.1796, 2016.
20. [20] A. Morecki, “Polish artificial pneumatic muscles,” Proc. of the 4th Int. Conf. on climbing and walking robot, Karlsruhe, September 24-26, 2001.
21. [21] N. Tsagarakis and D. G. Caldwell, “Improved modelling and assessment of pneumatic muscle actuators,” Proc. of int. conf. on robotics and automation, San Francisco, CA, April 24-28, pp. 3641-3646, IEEE, New York, 2000.
22. [22] M. Doumit, A. Fahim, and M. Munro, “Analytical modelling and experimental validation of the braided pneumatic muscle,” IEEE Trans. Robotics, Vol.25, No.6, pp. 1282-1291, 2009.
23. [23] F. Sorge and M. Cammalleri, “A theoretical approach to pneumatic muscle mechanics,” Proc. of IEEE/ASME int. conf. on advanced intelligent mechatronics, Wollongong, NSW, Australia, July 9-12, pp. 1021-1026, IEEE, New York, 2013.
24. [24] G. K. Klute and B. Hannaford, “Fatigue characteristic of McKibben artificial muscle actuators,” Proc. of int. conf. on intelligent robots and systems conf., Victoria, BC, Canada, October 13-17, pp. 1776-1781, IEEE, New York, 1998.
25. [25] D. A. Kingsley and R. D. Quinn, “Fatigue life and frequency response of braided pneumatic actuators,” Proc. of IEEE robotics and automation conf., Washington, DC, May 11-15, pp. 2830-2835, IEEE, New York, 2002.
26. [26] G. Belforte, T. Raparelli, and S. Sirolli, “A novel geometric Formula for Predicting Contractile Force in McKibben Pneumatic Muscles,” Int. J. of Automation Technology, Vol.11, No.3, pp. 368-377, 2017.
27. [27] S. Wakimoto, K. Suzumori, and J. Takeda, “Flexible artificial muscle by bundle of McKibben fiber actuators,” Proc. of IEEE/ASME int. conf. on advanced intelligent mechatronics, Budapest, July 3-7, pp. 457-462, New York: IEEE, 2011.
28. [28] T. Nozaki and Y. Noritsugu, “Motion analysis of McKibben type pneumatic rubber artificial muscle with finite element method,” Int. J. of Automation Technology, Vol.8, No.2, pp. 147-158, 2014.
29. [29] M. G. Antonelli, P. B. Zobel, F. Durante, and T. Raparelli, “Numerical modelling and experimental validation of a McKibben pneumatic muscle actuator,” J. of Intelligent Material Systems and Structures, doi: 10.1177/1045389X17698245, 2017.
30. [30] D. Sasaki, T. Noritsugu, and M. Takaiwa, “Development of Active Support Splint Driven by Pneumatic Soft Actuator (ASSIST),” J. of Robotics and Mechatronics, Vol.16, No.5, pp. 497-503, 2004.
31. [31] T. Noritsugu, D. Sasaki, M. Kameda, A. Fukunaga, and M. Takaiwa, “Wearable Power Assist Device for Standing Up Motion Using Pneumatic Rubber Artificial Muscles,” J. of Robotics and Mechatronics, Vol.19, No.6, pp. 619-628, 2007.
32. [32] H. Kobayashi, A. Takamitsu, and T. Hashimoto, “Muscle Suit Development and Factory Application,” Int. J. of Automation Technology, Vol.3, No.6, pp. 709-715, 2009.
33. [33] Y. Muramatsu, H. Kobayashi, Y. Sato, H. Jiaou, T. Hashimoto, and H. Kobayashi, “Quantitative Performance Analysis of Exoskeleton Augmentation Devices – Muscle Suit – for Manual Worker,” Int. J. of Automation Technology, Vol.5, No.4, pp. 559-567, 2011.
34. [34] H. Kobayashi, T. Hashimoto, S. Nakayama, and K. Irie, “Development of an Active Walker and its Effect,” J. of Robotics and Mechatronics, Vol.24, No.2, pp. 275-283, 2012.
35. [35] X. Li, T. Noritsugu, M. Takaiwa, and D. Sasaki, “Design of Wearable Power Assist Wear for Low Back Support Using Pneumatic Actuators,” Int. J. of Automation Technology, Vol.7, No.2, pp. 228-236, 2013.
36. [36] K. Nazarczuk, “Teorie sztucznych napedow miesniowych i jej zastosowanie do syntezy i sterowanie biomanipulatorow,” Ph.D. thesis, Warsaw Politecnical School, 1970.
37. [37] T. Nakamura, “Experimental Comparisons between McKibben Type Artificial Muscles and Straight Fibers Type Artificial Muscles,” Proc. of SPIE Int. Conf. on Smart Structures, Devices and Systems III, 2006.
38. [38] C. Ferraresi, W. Franco, and A. M. Bertetto, “Flexible Pneumatic Actuators: A comparison between the McKibben and the Straight Fibres Muscles,” J. of Robotics and Mechatronics, Vol.13, No.1, pp. 56-63, 2001.
39. [39] H. Tomori and T. Nakamura, “Theoretical Comparison of McKibben-Type Artificial Muscle and Novel Straight-Fiber-Type Artificial Muscle,” Int. J. of Automation Technology, Vol.5, No.4, pp. 544-550, 2011.
40. [40] T. Raparelli, P. B. Zobel, and F. Durante, “The Design of a 2-dof Robot for Functional Recovery Therapy driven by Pneumatic Muscles,” paper RD-078, RAAD 2001, 10th Int. Workshop on ROBOTICS IN ALPE – ADRIA – DANUBE REGION, Vienna, May 16-18, 2001.
41. [41] J. D. Ferry, “Viscoelastic Properties of Polymers,” John Wiley & Sons, Inc., New York, 1980.
42. [42] T. Raparelli, F. Durante, and P. Beomonte Zobel, “Numerical modelling and experimental validation of a pneumatic muscle actuator,” Proc. 4th JHPS Int. Symposium on Fluid Power, Tokyo ’99, November 15-17, 1999.
43. [43] T. Raparelli, P. B. Zobel, and F. Durante, “On the design of pneumatic muscle actuators,” 2nd Int. Fluidtechnisches Kolloquium, March 16-17, Dresda, 2000.
44. [44] T. Raparelli, F. Durante, and P. B. Zobel, “Una metodologia di progetto di attuatori a muscolo pneumatico,” XIV Congresso Nazionale AIMETA, Como, Italy, October, 1999.
45. [45] M. Zlokarnik, “Dimensional Analysis and Scale-up in Chemical Engineering,” Springer-Verlag, Berlin, 1991.