Publications

Ph. D. Thesis:

“Frictional Equilibrium Postures for Robotic Locomotion –
Computation, Geometric Characterization, and Stability Analysis”,
Supervised by Elon Rimon, Technion, May 2007 PDF
Awarded the Pnueli Prize of excellence, Faculty of Mechanical Engineering, Technion, 2008

Journals Papers:

  1.  Y. Or and E. Rimon, “Computation and Graphical Characterization of Robust
    Multiple-Contact Postures in Two-Dimensional Gravitational Environments”, Int. J. of
    Robotics Research, 25(11): 1071-1086, 2006 PDF
  2.  E. Rimon, R. Mason, J. W. Burdick and Y. Or, “A General Stance Stability Test
    Based on Stratified Morse Theory with Application to Quasi-Static Locomotion Planning”,
    IEEE Trans. on Robotics, 24(3):626-641, 2008 PDF
  3. Y. Or and R. M. Murray, “Dynamics and Stability of a Class of Low Reynolds
    Number Swimmers Near a Wall”, Physical Review E 79(4):045302, 2009 PDF,
    supplementary document PDF
  4. Y. Or and E. Rimon, “Analytic Characterization of a Class of 3-Contact
    Frictional Equilibrium Postures in 3D Gravitational Environments”,
    Int. J. of Robotics Research, 29(1): 3–22, 2010 PDF
  5. Darren G. Crowdy and Yizhar Or, “Two-dimensional point singularity model of a low Reynolds number swimmer near a wall”, Physical Review E 81(3):036313, 2010 PDF
  6.  Y. Or, “Dynamics and stability of Purcell’s three-link microswimmer near a wall”,
    Physical Review E 82(6):065302(R), 2010 PDF ; supplementary document PDF
  7.  Y. Or and A. R. Teel, “Zeno Stability of the Set-Valued Bouncing Ball”, technical note,
    IEEE Trans. On Automatic Control, 56(2):447-452, 2010.  PDF.
    A supplementary technical report with more details is available here.
  8. Y. Or and A. D. Ames, “Stability and Completion of Zeno Equilibria in Lagrangian Hybrid
    Systems”, IEEE Trans. On Automatic Control, 56(6):1322-1336, 2011 PDF
  9.  Y. Or, S. Zhang and R. M. Murray, “Dynamics and stability of low-Reynolds-number swimming near a wall”, SIAM J. of Applied Dynamical Systems, 10(3):1013-1041, 2011 PDF
  10.  Y. Or and E. Rimon, “Investigation of Painlevé’s paradox and dynamic jamming during mechanism sliding motion”, Nonlinear Dynamics, 67:1647–1668, 2012 PDF
  11. Y. Or, “Asymmetry and stability of shape kinematics in microswimmers motion”,
    Physical Review Letters 108:258101, 2012. Marked as “Editor’s Suggestion” PDF .
    Supplementary document available here.
  12. E. Passov and Y. Or, “Dynamics of Purcell’s three-link microswimmer with a passive elastic tail”, European Physical Journal E 35:78, 2012 PDF. Supplementary document available here.
  13.  Y. Or, “Painlevé’s Paradox and Dynamic Jamming in simple models of passive dynamic walking”, Regular and Chaotic Dynamics, 19(1):64-80, 2014. PDF
  14.  D. Alkaher, A. Moshaiov and Y. Or, “Guidance laws based on optimal feedback linearization peudo-control with time-to-go estimation”, AIAA Journal of Guidance, Control, and Dynamics,  37(4): 1298-1305, 2014. PDF
  15. E. Gutman and Y. Or, “Simple model of a planar undulating magnetic microswimmer”, Physical Review E 90:013012, 2014. PDF.
  16. B. Gamus and Y. Or, “Analysis of simple rigid-body models of dynamic bipedal walking under stick-slip transitions”, SIAM J. Applied Dynamical Systems, 14(2):609-642, 2015. PDF . Supplementary document available here.
  17. B. Jang, E. Gutman, N. Stucki, B. Seitz, P. García-Wendel, T. Newton, J. Pokki, O. Ergeneman, S. Pané, Y. Or, and B. J. Nelson,  “Undulatory locomotion of magnetic multi-link nanoswimmers”, ACS Nano Letters 15(7):4829-4833, 2015.
  18.  E. Gutman and Y. Or,  “Symmetries and gaits for Purcell’s three-link microswimmer model”, IEEE Transactions on Robotics 32(1):53-69, 2016. PDF
  19. M. Moravia and Y. Or,  “Analysis of foot slippage effects on an actuated spring-mass model of dynamic legged locomotion”, International Journal of Advanced Robotic Systems 13:69, 2016. PDF
  20. E. Gutman and Y. Or, “Optimizing an undulating magnetic microswimmer for cargo towing”,
    Physical Review E 93(6):063105, 2016. PDF
  21. O. Wiezel and Y. Or, “Optimization and small-amplitude analysis of Purcell’s three-link microswimmer model”, Proc. Roy. Soc. A, 472: 20160425, 2016. PDF
  22.  Y. Or and E. Rimon,  “Characterization of frictional multi-legged Equilibrium Postures on Uneven Terrains”, International Journal of Robotics Research, 36(1):105-128, 2017. PDF
  23.  O. Chakon and Y. Or, “Analysis of underactuated dynamic locomotion systems using perturbation expansion – the twistcar toy example”,  J. Nonlinear Science, 27(4):1215-1234, 2017. PDF, MOVIE
  24.  P. L. Varkonyi and Y. Or, “Lyapunov stability of a rigid body with two frictional contacts”, Nonlinear Dynamics 88(1),363-393, 2017. PDF
  25. R. Keren and Y. Or, “Energy performance analysis of a backpack suspension system with a timed clutch for human load carriage”, published online at Mechanism and Machine Theory (Elsevier) 120 (2018), pp. 250–264. PDF
  26. B. Gamus, E. Ben-Haim, L. Salem, A. D. Gat and Y. Or, “Interaction between Inertia, Viscosity and Elasticity in Soft Robotic Actuator with Fluidic Network”, IEEE Trans. Robotics, 34(1):81-90, 2018. PDF 
  27. A. Cohen and Y. Or, “Modelling the Dynamics and Control of Rehabilitative Exoskeleton with Robotic Crutches”, International Journal of Advanced Robotic Systems (Sage Publication),15(2), 1729881418761137, 2018. PDF  
  28. Y. Harduf, D. Jin, Y. Or, and L. Zhang, “Nonlinear parametric excitation effect induces stability transitions in swimming direction of flexible superparamagnetic microswimmers “, Soft Robotics 5(4):389-398, 2018. PDF 
  29. R. Keren and Y. Or, “Theoretical Analysis of a passive wearable spring-clutch mechanism for reducing metabolic energy cost during human walking”, ASME J. Mechanisms and Robotics, 10:061004, 2018. PDF 
  30. E. Virozub, O. Wiezel and Y. Or, “Multi-link swimmers: experiments and theoretical investigation using ‘perfect fluid’ Model”, Robotica, DOI: 10.1017/S0263574718001510.
    PDF. Supplementary Movie
  31. T. Yona and Y. Or, “The wheeled three-link snake model: Singularities in nonholonomic constraints and stick-slip hybrid dynamics induced by Coulomb friction.”, Nonlinear Dynamics, 95:2307-2324, 2019. PDF, MOVIE
  32. Jang, A. Hong, C. Alcantara, G. Chatzipripiridis, X. Martí, E. Pellicer, J. Sort, Y. Harduf,
    Y. Or, B. J. Nelson and S. Pané, “Programmable Locomotion Mechanisms of Hard-Magnetic Nanowires Near a Surface Boundary”, ACS Applied Materials & Interfaces, 11(3):3214–3223, 2019.
  33. I. Fouxon and Y. Or, Inertial self-propulsion of spherical microswimmers by rotation-translation coupling. Physical Review Fluids. 4(2), 023101, 2019. arXiv preprint arXiv:1710.10677.
  34. O. Wiezel, L. Giraldi, A. DeSimone, Y. Or and F. Alouges, “Energy-optimal small-amplitude strokes for multi-link microswimmers: Purcell’s loops and Taylor’s waves reconciled”. New J. Phys.21:043050, 2019. arXiv preprint arXiv:1801.04687.
  35. Salem, B. Gamus, Y. Or and A. D. Gat, “Leveraging viscous-peeling in fluid-driven soft-actuators and reconfigurable microchannel networks”.Soft Robotics, 7(1):76-84, 2020. arXiv preprint arXiv:1907.03286. Movie
  36. Ben-Haim, L. Salem, Y. Or and A. D. Gat, ” Single-input control of multiple fluid-driven elastic actuators via interaction between bi-stability and viscosity”, Soft Robotics 7(2):259-265, 2020. arXiv preprint arXiv:1903.04280
  37. B. Gamus, L. Salem, A. D. Gat and Y. Or, “Understanding Legged Crawling for Soft-Robotics”,IEEE Robotics and Automation Letters 5(2):1397-1404, 2020. arXiv preprint arXiv:1911.05227 . Movie
  38. Gamus, A. D. Gat and Y. Or, “Dynamic Inchworm Crawling: Performance Analysis and Optimization of a Three-link Robot”, IEEE Robotics and Automation Letters, 6(1), 111-118, 2020.‏ arXiv preprint arXiv:2006.01990, movie.
  39. J. Wu, B. Jang, Y. Harduf, Z. Chapnik,  X. Chen, J. Puigmartí-Luis, O. Ergeneman, B. J. Nelson, Y. Or and S. Pané, “Helical Klinotactic Locomotion of Two-Link Nanoswimmers with Dual-Function Drug-Loaded Soft Polysaccharide Hinges”, to appear in Advanced Science,
    DOI: 10.1002/advs.202004458.
  40. Y. Or and P.L. Varkonyi, “Experimental Verification of Stability Theory for a Planar Rigid Body with Two Unilateral Frictional Contacts”, IEEE Transactions on Robotics.  37(5): 1634-1648, 2021. DOI: 10.1109/TRO.2021.3064871, arXiv preprint, LINK to movie.
  41. O. Halvani and Y. Or, “Nonholonomic dynamics of the Twistcar vehicle: asymptotic analysis and hybrid dynamics of frictional skidding”, submitted. PDF
  42. Ben-Haim, D. Ilssar, Or, Yizhar, Y. Or and A. D. Gat, “Viscous flow-fields in hyperelastic Chambers”, submitted. arXiv:2105.10290 .
  43. L. Salem, A. D. Gat and Y. Or, “Fluid-driven traveling waves in soft robots”, submitted. arXiv:2108.07579 .
  44. Wiezel, S. Ramasamy, N. Justus, Y. Or and R. L. Hatton, “Geometric analysis of gaits and optimal control for three-link kinematic swimmers”. Submitted. arXiv preprint arXiv:2109.06511.‏
  45. Fouxon, A. Leshansky, B. Rubinstein, and Y. Or, “Lamb-type solution and properties of unsteady Stokes equations”, Submitted, arXiv preprint: arXiv:2110.00387 .

Refereed Papers in Conference Proceedings:

  1.  Y. Or and E. Rimon, “Robust Multiple-Contact Postures in a Two-Dimensional Gravitational Field”, Proc. of 2004 IEEE Int. Conf. on Robotics and Automation, pp. 4783-4788  PDF
  2. Y. Or and E. Rimon, “Computation and Graphical Characterization of Robust Multiple-Contact Postures in 2D Gravitational Environments”, Proc. of 2005 IEEE Int. Conf. on Robotics and Automation, pp. 247-252  PDF
  3.  Y. Or and E. Rimon, “Computing 3-Legged Equilibrium Stances in Three-Dimensional Gravitational Environments”, Proc. of 2006 IEEE Int. Conf. on Robotics and Automation, pp. 1984-1989  PDF
  4.  Y. Or and E. Rimon, “Geometric Characterization and Experimental Validation of Frictional 3-Contact Equilibrium Stances in Three-Dimensions”, Proc. of 2007 IEEE Int. Conf. on Robotics and Automation, pp. 193-198  PDF
  5.  D. Meltz, Y. Or and E. Rimon, “Experimental Verification and Graphical Characterization of Dynamic Jamming in Frictional Rigid-Body Mechanics”, Proc. of 2007 IEEE Int. Conf. on Robotics and Automation, pp. 580-585  PDF
  6.  Y. Or and E. Rimon, “On the Hybrid Dynamics of Planar Mechanisms Supported by Frictional Contacts. I: Necessary Conditions for Stability”, Proc. of 2008 IEEE Int. Conf. on Robotics and Automation, pp. 1213-1218  PDF
  7.  Y. Or and E. Rimon, “On the Hybrid Dynamics of Planar Mechanisms Supported by Frictional Contacts. II: Stability of Two-Contact Rigid Body Postures”, Proc. of 2008 IEEE Int. Conf. on Robotics and Automation, pp. 1219-1224 PDF
  8.  Y. Or and A. D. Ames, “Stability of Zeno Equilibria in Lagrangian Hybrid Systems”, Proc. IEEE Conf. on Decision and Control 2008, pp. 2770-2775 PDF
  9.  Y. Or and A. D. Ames, “Formal and Practical Completion of Lagrangian Hybrid Systems”, Proc. American Control Conference (ACC) 2009, pp. 4221-4226 PDF
  10.  Y. Or and A. D. Ames, “Existence of Periodic Orbits with Zeno Behavior in Completed Lagrangian Hybrid Systems”, Hybrid Systems: Computation and Control, Lecture Notes on Computer Science, Springer-Verlag, 2009, pp. 291-305 PDF.
    Technical report (long) PDF
  11.  Y. Or, J. Vankerschaver, S. D. Kelly, R. M. Murray and J. E. Marsden, “Geometric Control of Particle Manipulation in a Two-Dimensional Fluid”, to appear in Proc. IEEE Conf. on Decision and Control (CDC) 2009 PDF
    winner of Guan Zhao-Zhi Best Paper Award
  12.  S. Zhang, Y. Or and R. M. Murray, “Experimental demonstration of the dynamics and stability of a low Reynolds number swimmer near a plane wall”, in Proc. 2010 American Control Conference (ACC) pp. 4205-4210 PDF
    Supplemental video files can be found here
  13.  Y. Or and A. R. Teel, “Using the Set-Valued Bouncing Ball for Bounding Zeno Solutions of Lagrangian Hybrid Systems”, in Proc. 2010 IFAC Symposium on Nonlinear Control Systems (NOLCOS2010) pp. 801-806, PDF
  14.  J. Spitz, Y Or and M. Zacksenhouse, “Towards a Biologically Inspired Open Loop
    Controller for Dynamic Biped Locomotion”, Proc. 2011 IEEE conference on Robotics and
    Biomimetics (ROBIO), pp. 503-508, 2011. PDF
  15.  B. Gamus and Y. Or. “Analysis of dynamic bipedal robot locomotion with stick-slip transitions”,  Proc. 2013 IEEE Int. Conf. on Robotics and Automation (ICRA), pp. 3333-3340, 2013. PDF
  16. H. Ziso, Y. Or and M. Shoham. “Numerical model of magnetic bead chain for minimal radius of curvature passage based on linear programming”, Proc. 14th World Congress in Mechanism and Machine Science, pp. 606-611, Taipei, Taiwan, 25-30 October, 2015. PDF
  17.  O. Wiezel and Y. Or, “Using optimal control to obtain maximum displacement gait for Purcell’s three-link swimmer”, Proc. 2016 IEEE Conf. on Decision and Control (CDC), pp. 4463-4468. Las Vegas, USA, 12-15 December 2016. PDF
  18. W. Ma, Y. Or and A. D. Ames, “Dynamic Walking on Slippery Surfaces: Demonstrating Stable Bipedal Gaits with Planned Ground Slippage”, Proceedings of 2019 IEEE Int. Conf. on Robotics and Automation pp. 3705-3711, May 20-24, 2019, Montreal, Canada. PDF
  19. E. Ambrose, N. Csomay-Shanklin, Y. Or and A. D. Ames, “Design and Comparative Analysis of 1D Hopping Robots”, to appear in Proc. 2019 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), Nov. 4 – 8, 2019 Macao, China. PDF

Technical Reports:

  1. Y. Or and E. Rimon, “Computation and Graphic Characterization of Robust Multiple-Contact Postures in 2D Gravitational Environments”, 2004, PDF
  2. Y. Or and E. Rimon, “Computation of Multiple-Contact Frictional Equilibrium Postures in Three-Dimensional Gravitational Environments”, 2005  PDF
  3. Y. Or and E. Rimon, “New Results on Computing Frictional Equilibrium Stances in Three-Dimensional Gravitational Environments”, 2006  PDF
  4. Y. Or and A. D. Ames, “Stability of Zeno Equilibria in Lagrangian Hybrid Systems”, California Inst. of Technology, 2008, Technical report CaltechCDSTR:2008.002  PDF
  5. Y. Or and A. D. Ames, “Existence of Periodic Orbits in Completed Lagrangian Hybrid Systems with Non-Plastic Collisions”, 2008, Technical Report PDF
  6. Y. Or and A. R. Teel, “The Set-Valued Bouncing Ball”, longer version PDF.
  7. Y. Or and E. Rimon, “Computation of frictional multi-contact equilibrium stances and postures on 3D uneven tame terrains”, Technical Report PDF.