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  • Technical Review
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A concise guide to modelling the physics of embodied intelligence in soft robotics

Abstract

Embodied intelligence (intelligence that requires and leverages a physical body) is a well-known paradigm in soft robotics, but its mathematical description and consequent computational modelling remain elusive, with a need for models that can be used for design and control purposes. We argue that filling this gap will enable full uptake of embodied intelligence in soft robots. We provide a concise guide to the main mathematical modelling approaches, and consequent computational modelling strategies, that can be used to describe soft robots and their physical interactions with the surrounding environment, including fluid and solid media. We aim to convey the challenges and opportunities within the context of modelling the physical interactions underpinning embodied intelligence. We emphasize that interdisciplinary work is required, especially in the context of fully coupled robot–environment interaction modelling. Promoting this dialogue across disciplines is a necessary step to further advance the field of soft robotics.

Key points

  • Embodied intelligence is one of the main motivations for soft robotics.

  • Body compliance enables embodied intelligence and helps to simplify the control of robots for achieving the required tasks in complex environments.

  • A full mathematical description of the deformations of a soft robot, given by its internal interactions with actuators and by the external interactions with the surrounding environment, can be the tool for mastering body compliance and embodied intelligence.

  • Relevant modelling and computational techniques are within grasp, in an interdisciplinary effort.

  • Soft robotics can transition to a model-informed discipline, with embodied-intelligence-based design and control, that can pave the way towards soft-robot digital twins.

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Fig. 1: The three main components of a typical sensorimotor scheme, either for a robot or a biological system.
Fig. 2: Scope of this Technical Review in modelling the physics of embodied intelligence.
Fig. 3: Examples of practical simulations in the context of internal interactions.
Fig. 4: Examples of practical simulations in the context of external interactions.

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References

  1. Kim, S., Laschi, C. & Trimmer, B. Soft robotics: a bioinspired evolution in robotics. Trends Biotechnol. 31, 287–294 (2013).

    Article  Google Scholar 

  2. Pfeifer, R., Lungarella, M. & Iida, F. Self-organization, embodiment, and biologically inspired robotics. Science 318, 1088–1093 (2007).

    Article  ADS  Google Scholar 

  3. Blickhan, R. et al. Intelligence by mechanics. Phil. Trans. R. Soc. A 365, 199–220 (2007).

    Article  ADS  MathSciNet  Google Scholar 

  4. Niederer, S. A., Sacks, M. S., Girolami, M. & Willcox, K. Scaling digital twins from the artisanal to the industrial. Nat. Comput. Sci. 1, 313–320 (2021).

    Article  Google Scholar 

  5. Brunton, S. L. et al. Data-driven aerospace engineering: reframing the industry with machine learning. AIAA J. 59, 2820–2847 (2021).

    Google Scholar 

  6. Xavier, M. S., Fleming, A. J. & Yong, Y. K. Finite element modeling of soft fluidic actuators: overview and recent developments. Adv. Intell. Syst. 3, 2000187 (2021).

    Article  Google Scholar 

  7. Vanneste, F., Goury, O. & Duriez, C. in 2021 IEEE 4th Int. Conf. Soft Robot. 636–642 (IEEE, 2021).

  8. Duriez, C. & Bieze, T. in Soft Robotics: Trends, Applications and Challenges (eds Laschi, C. et al.) 103–109 (Springer, 2017).

  9. Goury, O. & Duriez, C. Fast, generic, and reliable control and simulation of soft robots using model order reduction. IEEE Trans. Robot. 34, 1565–1576 (2018).

    Article  Google Scholar 

  10. Hu, Y. et al. in 2019 Int. Conf. Robot. Autom. 6265–6271 (IEEE, 2019).

  11. Hiller, J. & Lipson, H. Dynamic simulation of soft multimaterial 3D-printed objects. Soft Robot. 1, 88–101 (2014).

    Article  Google Scholar 

  12. Cheney, N., MacCurdy, R., Clune, J. & Lipson, H. Unshackling evolution: evolving soft robots with multiple materials and a powerful generative encoding. ACM SIGEVOlution 7, 11–23 (2014).

    Article  Google Scholar 

  13. Dassault Systemes. Abaqus Unified FEA. 3DS https://www.3ds.com/products-services/simulia/products/abaqus/ (2021).

  14. Ansys. Ansys software. Ansys https://www.ansys.com (2021).

  15. COMSOL. COMSOL software. COMSOL https://www.comsol.com (2021).

  16. Altair. Altair software. Altair https://www.altair.com (2021).

  17. Turner, M., Peiró, J. & Moxey, D. Curvilinear mesh generation using a variational framework. Comput. Aided Des. 103, 73–91 (2018).

    Article  MathSciNet  Google Scholar 

  18. Mengaldo, G. et al. Industry-relevant implicit large-eddy simulation of a high-performance road car via spectral/hp element methods. SIAM Rev. 63, 723–755 (2021).

    Article  MathSciNet  MATH  Google Scholar 

  19. Cottrell, J. A., Hughes, T. J. & Bazilevs, Y. Isogeometric Analysis: Toward Integration of CAD and FEA (Wiley, 2009).

  20. Hoshyari, S., Xu, H., Knoop, E., Coros, S. & Bächer, M. Vibration-minimizing motion retargeting for robotic characters. ACM Trans. Graph. 38, 102 (2019).

    Article  Google Scholar 

  21. Adagolodjo, Y., Renda, F. & Duriez, C. Coupling numerical deformable models in global and reduced coordinates for the simulation of the direct and the inverse kinematics of soft robots. IEEE Robot. Autom. Lett. 6, 3910–3917 (2021).

    Article  Google Scholar 

  22. Antman, S. Nonlinear Problems of Elasticity (Springer, 2006).

  23. Meier, C., Popp, A. & Wall, W. A. Geometrically exact finite element formulations for slender beams: Kirchhoff–Love theory versus Simo–Reissner theory. Arch. Comput. Methods Eng. 26, 163–243 (2019).

    Article  MathSciNet  Google Scholar 

  24. Shabana, A. A. Continuum-based geometry/analysis approach for flexible and soft robotic systems. Soft Robot. 5, 613–621 (2018).

    Article  Google Scholar 

  25. Boyer, F., Lebastard, V., Candelier, F. & Renda, F. Dynamics of continuum and soft robots: a strain parameterization based approach. IEEE Trans. Robot. 37, 847–863 (2020).

    Article  Google Scholar 

  26. Boyer, F. & Renda, F. Poincaré’s equations for cosserat media: application to shells. J. Nonlinear Sci. 27, 1–44 (2017).

    Article  ADS  MathSciNet  MATH  Google Scholar 

  27. Renda, F. & Seneviratne, L. in 2018 IEEE Int. Conf. Robot. Autom. 1567–1574 (IEEE, 2018).

  28. Gazzola, M., Dudte, L., McCormick, A. & Mahadevan, L. Forward and inverse problems in the mechanics of soft filaments. R. Soc. Open Sci. 5, 171628 (2018).

    Article  ADS  MathSciNet  Google Scholar 

  29. Mathew, A. T., Hmida, I. B., Armanini, C., Boyer, F. & Renda, F. SoRoSim: a MATLAB toolbox for soft robotics based on the geometric variable-strain approach. Preprint at arXiv https://arxiv.org/abs/2107.05494 (2021).

  30. Fu, Q. et al. Lateral oscillation and body compliance help snakes and snake robots stably traverse large, smooth obstacles. Integr. Comp. Biol. 60, 171–179 (2020).

    Article  Google Scholar 

  31. Chirikjian, G. S. & Burdick, J. W. A modal approach to hyper-redundant manipulator kinematics. IEEE Trans. Robot. Autom. 10, 343–354 (1994).

    Article  Google Scholar 

  32. Kim, B., Ha, J., Park, F. C. & Dupont, P. E. in 2014 IEEE Int. Conf. Robot. Autom. 5374–5379 (IEEE, 2014).

  33. Suzumori, K., Iikura, S. & Tanaka, H. in Proc. 1991 IEEE Int. Conf. Robot. Autom. 1622–1623 (IEEE, 1991).

  34. Webster III, R. J. & Jones, B. A. Design and kinematic modeling of constant curvature continuum robots: a review. Int. J. Robot. Res. 29, 1661–1683 (2010).

    Article  Google Scholar 

  35. George Thuruthel, T., Ansari, Y., Falotico, E. & Laschi, C. Control strategies for soft robotic manipulators: a survey. Soft Robot. 5, 149–163 (2018).

    Article  Google Scholar 

  36. Kim, D. et al. Review of machine learning methods in soft robotics. PLoS ONE 16, e0246102 (2021).

    Article  Google Scholar 

  37. Wang, X., Li, Y. & Kwok, K.-W. A survey for machine learning-based control of continuum robots. Front. Robot. AI 8, 730330 (2021).

    Article  ADS  Google Scholar 

  38. Giorelli, M. et al. Neural network and Jacobian method for solving the inverse statics of a cable-driven soft arm with nonconstant curvature. IEEE Trans. Robot. 31, 823–834 (2015).

    Article  Google Scholar 

  39. Juang, J. N. Applied System Identification (Prentice Hall, 1994).

  40. Brunton, S. L. & Kutz, J. N. Data-Driven Science and Engineering: Machine Learning, Dynamical Systems, and Control (Cambridge Univ. Press, 2019).

  41. Benner, P., Gugercin, S. & Willcox, K. A survey of projection-based model reduction methods for parametric dynamical systems. SIAM Rev. 57, 483–531 (2015).

    Article  MathSciNet  MATH  Google Scholar 

  42. Peherstorfer, B. & Willcox, K. Data-driven operator inference for nonintrusive projection-based model reduction. Comput. Methods Appl. Mech. Eng. 306, 196–215 (2016).

    Article  ADS  MathSciNet  MATH  Google Scholar 

  43. Brunton, S. L., Proctor, J. L. & Kutz, J. N. Discovering governing equations from data by sparse identification of nonlinear dynamical systems. Proc. Natl Acad. Sci. USA 113, 3932–3937 (2016).

    Article  ADS  MathSciNet  MATH  Google Scholar 

  44. Loiseau, J.-C. & Brunton, S. L. Constrained sparse Galerkin regression. J. Fluid Mech. 838, 42–67 (2018).

    Article  ADS  MathSciNet  MATH  Google Scholar 

  45. Qian, E., Kramer, B., Peherstorfer, B. & Willcox, K. Lift & learn: physics-informed machine learning for large-scale nonlinear dynamical systems. Physica D 406, 132401 (2020).

    Article  MathSciNet  MATH  Google Scholar 

  46. Dowell, E. H. & Hall, K. C. Modeling of fluid-structure interaction. Annu. Rev. Fluid Mech. 33, 445–490 (2001).

    Article  ADS  MATH  Google Scholar 

  47. Hou, G., Wang, J. & Layton, A. Numerical methods for fluid-structure interaction — a review. Commun. Comput. Phys. 12, 337–377 (2012).

    Article  MathSciNet  MATH  Google Scholar 

  48. Souli, M. & Benson, D. J. Arbitrary Lagrangian Eulerian and Fluid–Structure Interaction: Numerical Simulation (Wiley, 2013).

  49. Mittal, R. & Iaccarino, G. Immersed boundary methods. Annu. Rev. Fluid Mech. 37, 239–261 (2005).

    Article  ADS  MathSciNet  MATH  Google Scholar 

  50. Taira, K. & Colonius, T. The immersed boundary method: a projection approach. J. Comput. Phys. 225, 2118–2137 (2007).

    Article  ADS  MathSciNet  MATH  Google Scholar 

  51. Goza, A. & Colonius, T. A strongly-coupled immersed-boundary formulation for thin elastic structures. J. Comput. Phys. 336, 401–411 (2017).

    Article  ADS  MathSciNet  MATH  Google Scholar 

  52. Dickinson, M. H. et al. How animals move: an integrative view. Science 288, 100–106 (2000).

    Article  ADS  Google Scholar 

  53. Lauder, G. V. Fish locomotion: recent advances and new directions. Annu. Rev. Mar. Sci. 7, 521–545 (2015).

    Article  ADS  Google Scholar 

  54. FLOW-3D. FLOW-3D software. FLOW-3D https://www.flow3d.com/products/flow-3d/ (2021).

  55. ADINA. ADINA software. ADINA http://www.adina.com (2021).

  56. Weller, H. G., Tabor, G., Jasak, H. & Fureby, C. A tensorial approach to computational continuum mechanics using object-oriented techniques. Comput. Phys. 12, 620–631 (1998).

    Article  ADS  Google Scholar 

  57. Renda, F. et al. A unified multi-soft-body dynamic model for underwater soft robots. Int. J. Robot. Res. 37, 648–666 (2018).

    Article  Google Scholar 

  58. Armanini, C. et al. Flagellate underwater robotics at macroscale: design, modeling, and characterization. IEEE Trans. Robot. 38, 731–747 (2021).

    Article  Google Scholar 

  59. Duraisamy, K., Iaccarino, G. & Xiao, H. Turbulence modeling in the age of data. Annu. Rev. Fluid Mech. 51, 357–377 (2019).

    Article  ADS  MathSciNet  MATH  Google Scholar 

  60. Brunton, S. L., Noack, B. R. & Koumoutsakos, P. Machine learning for fluid mechanics. Annu. Rev. Fluid Mech. 52, 477–508 (2020).

    Article  ADS  MATH  Google Scholar 

  61. Vinuesa, R. & Brunton, S. L. The potential of machine learning to enhance computational fluid dynamics. Preprint at arXiv https://arxiv.org/abs/2110.02085 (2021).

  62. Bar-Sinai, Y., Hoyer, S., Hickey, J. & Brenner, M. P. Learning data-driven discretizations for partial differential equations. Proc. Natl Acad. Sci. USA 116, 15344–15349 (2019).

    Article  ADS  MathSciNet  MATH  Google Scholar 

  63. Kochkov, D. et al. Machine learning accelerated computational fluid dynamics. Preprint at arXiv https://arxiv.org/abs/2102.01010 (2021).

  64. Wang, R., Walters, R. & Yu, R. Incorporating symmetry into deep dynamics models for improved generalization. Preprint at arXiv https://arxiv.org/abs/2002.03061 (2020).

  65. Li, Z. et al. Fourier neural operator for parametric partial differential equations. Preprint at arXiv https://arxiv.org/abs/2010.08895 (2020).

  66. Ling, J., Kurzawski, A. & Templeton, J. Reynolds averaged turbulence modelling using deep neural networks with embedded invariance. J. Fluid Mech. 807, 155–166 (2016).

    Article  ADS  MathSciNet  MATH  Google Scholar 

  67. Maulik, R., San, O., Rasheed, A. & Vedula, P. Subgrid modelling for two-dimensional turbulence using neural networks. J. Fluid Mech. 858, 122–144 (2019).

    Article  ADS  MathSciNet  MATH  Google Scholar 

  68. Novati, G., de Laroussilhe, H. L. & Koumoutsakos, P. Automating turbulence modelling by multi-agent reinforcement learning. Nat. Mach. Intell. 3, 87–96 (2021).

    Article  Google Scholar 

  69. Beetham, S. & Capecelatro, J. Formulating turbulence closures using sparse regression with embedded form invariance. Phys. Rev. Fluids 5, 084611 (2020).

    Article  ADS  Google Scholar 

  70. Beetham, S., Fox, R. O. & Capecelatro, J. Sparse identification of multiphase turbulence closures for coupled fluid–particle flows. J. Fluid Mech. 914, A11 (2021).

    Article  ADS  MathSciNet  MATH  Google Scholar 

  71. Taira, K. et al. Modal analysis of fluid flows: an overview. AIAA J. 55, 4013–4041 (2017).

    Article  ADS  Google Scholar 

  72. Loiseau, J.-C., Noack, B. R. & Brunton, S. L. Sparse reduced-order modeling: sensor-based dynamics to full-state estimation. J. Fluid Mech. 844, 459–490 (2018).

    Article  ADS  MATH  Google Scholar 

  73. Deng, N., Noack, B. R., Morzynski, M. & Pastur, L. R. Low-order model for successive bifurcations of the fluidic pinball. J. Fluid Mech. 884, A37 (2020).

    Article  ADS  MathSciNet  MATH  Google Scholar 

  74. Deng, N., Noack, B. R., Morzyński, M. & Pastur, L. R. Galerkin force model for transient and post-transient dynamics of the fluidic pinball. J. Fluid Mech. 918, A4 (2021).

    Article  ADS  MathSciNet  MATH  Google Scholar 

  75. Lee, K. & Carlberg, K. T. Model reduction of dynamical systems on nonlinear manifolds using deep convolutional autoencoders. J. Comput. Phys. 404, 108973 (2020).

    Article  MathSciNet  MATH  Google Scholar 

  76. Raissi, M., Perdikaris, P. & Karniadakis, G. E. Physics-informed neural networks: a deep learning framework for solving forward and inverse problems involving nonlinear partial differential equations. J. Comput. Phys. 378, 686–707 (2019).

    Article  ADS  MathSciNet  MATH  Google Scholar 

  77. Lu, L., Jin, P., Pang, G., Zhang, Z. & Karniadakis, G. E. Learning nonlinear operators via DeepONet based on the universal approximation theorem of operators. Nat. Mach. Intell. 3, 218–229 (2021).

    Article  Google Scholar 

  78. Shi, G. et al. in 2019 Int. Conf. Robot. Autom. 9784–9790 (IEEE, 2019).

  79. Johnson, K. L. & Johnson, K. L. Contact Mechanics (Cambridge Univ. Press, 1987).

  80. Vakis, A. I. et al. Modeling and simulation in tribology across scales: an overview. Tribol. Int. 125, 169–199 (2018).

    Article  Google Scholar 

  81. Dalvi, S. et al. Linking energy loss in soft adhesion to surface roughness. Proc. Natl Acad. Sci. USA 116, 25484–25490 (2019).

    Article  ADS  Google Scholar 

  82. Studer, C. & Glocker, C. Simulation of non-smooth mechanical systems with many unilateral constraints 1597–1606 (Eindhoven Univ., 2005).

  83. Acary, V. Projected event-capturing time-stepping schemes for nonsmooth mechanical systems with unilateral contact and Coulomb’s friction. Comput. Methods Appl. Mech. Eng. 256, 224–250 (2013).

    Article  ADS  MathSciNet  MATH  Google Scholar 

  84. Coevoet, E., Escande, A. & Duriez, C. Optimization-based inverse model of soft robots with contact handling. IEEE Robot. Autom. Lett. 2, 1413–1419 (2017).

    Article  Google Scholar 

  85. Collins, J., Chand, S., Vanderkop, A. & Howard, D. A review of physics simulators for robotic applications. IEEE Access 9, 51416–51431 (2021).

    Article  Google Scholar 

  86. Simulation Open Framework Architecture. SOFA framework. SOFA https://www.sofa-framework.org (2021).

  87. Xu, J., Aykut, T., Ma, D. & Steinbach, E. 6DLS: modeling nonplanar frictional surface contacts for grasping using 6-D limit surfaces. IEEE Trans. Robot. 37, 2099–2116 (2021).

    Article  Google Scholar 

  88. Xydas, N. & Kao, I. Modeling of contact mechanics and friction limit surfaces for soft fingers in robotics, with experimental results. Int. J. Robot. Res. 18, 941–950 (1999).

    Article  Google Scholar 

  89. Majidi, C., Shepherd, R. F., Kramer, R. K., Whitesides, G. M. & Wood, R. J. Influence of surface traction on soft robot undulation. Int. J. Robot. Res. 32, 1577–1584 (2013).

    Article  Google Scholar 

  90. Todorov, E., Erez, T. & Tassa, Y. in 2012 IEEE/RSJ Int. Conf. Intell. Robots Syst. 5026–5033 (IEEE, 2012).

  91. Deimel, R. & Brock, O. A novel type of compliant and underactuated robotic hand for dexterous grasping. Int. J. Robot. Res. 35, 161–185 (2016).

    Article  Google Scholar 

  92. Lipson, H. & Pollack, J. B. Automatic design and manufacture of robotic lifeforms. Nature 406, 974–978 (2000).

    Article  ADS  Google Scholar 

  93. Hiller, J. & Lipson, H. Automatic design and manufacture of soft robots. IEEE Trans. Robot. 28, 457–466 (2011).

    Article  Google Scholar 

  94. Coevoet, E., Escande, A. & Duriez, C. in 2019 2nd IEEE Int. Conf. Soft Robot. 739–745 (IEEE, 2019).

  95. Hwangbo, J. et al. Learning agile and dynamic motor skills for legged robots. Sci. Robot. 4 (2019).

  96. Golemo, F., Taiga, A. A., Courville, A. & Oudeyer, P.-Y. in Conf. Robot Learn. 817–828 (PMLR, 2018).

  97. Battaglia, P. et al. Interaction networks for learning about objects, relations and physics. Adv. Neural Inf. Proc. Syst. 29 (2016).

  98. Jiang, Y., et al. in Learn. Dyn. Control Conf. 378–390 (PMLR, 2022).

  99. Sundaram, S. et al. Learning the signatures of the human grasp using a scalable tactile glove. Nature 569, 698–702 (2019).

    Article  ADS  Google Scholar 

  100. Lipson, H. Challenges and opportunities for design, simulation, and fabrication of soft robots. Soft Robot. 1, 21–27 (2014).

    Article  Google Scholar 

  101. Calisti, M. & Laschi, C. Morphological and control criteria for self-stable underwater hopping. Bioinspir. Biomim. 13, 016001 (2017).

    Article  ADS  Google Scholar 

  102. Chenevier, J., González, D., Aguado, J. V., Chinesta, F. & Cueto, E. Reduced-order modeling of soft robots. PLoS ONE 13, e0192052 (2018).

    Article  Google Scholar 

  103. Full, R. J. & Koditschek, D. E. Templates and anchors: neuromechanical hypotheses of legged locomotion on land. J. Exp. Biol. 202, 3325–3332 (1999).

    Article  Google Scholar 

  104. Picardi, G. et al. Bioinspired underwater legged robot for seabed exploration with low environmental disturbance. Sci. Robot. 5 (2020).

  105. Bujard, T., Giorgio-Serchi, F. & Weymouth, G. D. A resonant squid-inspired robot unlocks biological propulsive efficiency. Sci. Robot. 6, eabd2971 (2021).

    Article  Google Scholar 

  106. Renda, F., Boyer, F., Dias, J. & Seneviratne, L. Discrete Cosserat approach for multisection soft manipulator dynamics. IEEE Trans. Robot. 34, 1518–1533 (2018).

    Article  Google Scholar 

  107. Renda, F., Cianchetti, M., Giorelli, M., Arienti, A. & Laschi, C. A 3D steady-state model of a tendon-driven continuum soft manipulator inspired by the octopus arm. Bioinspir. Biomim. 7, 025006 (2012).

    Article  ADS  Google Scholar 

  108. Navarro, S. E. et al. A model-based sensor fusion approach for force and shape estimation in soft robotics. IEEE Robot. Autom. Lett. 5, 5621–5628 (2020).

    Article  Google Scholar 

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Acknowledgements

G.M. acknowledges NUS support through his start-up grant (R-265-000-A36-133). G.S.C. acknowledges MOE Tier 1 grant (R-265-000-655-114). C.L. acknowledges NUS support through her start-up grant (R-265-000-A31-133 and R-265-000-A31-731). Part of this research is supported by the National Research Foundation, Singapore, under its Medium Sized Centre Programme — Centre for Advanced Robotics Technology Innovation (CARTIN). G.M., G.S.C. and C.L. acknowledge MOE Tier 2 grant ‘REBOT’. This work was supported in part by the US Office of Naval Research Global under grant N62909-21-1-2033 and Khalifa University of Science and Technology under grants CIRA-2020-074 and RC1-2018-KUCARS.

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Correspondence to Gianmarco Mengaldo or Cecilia Laschi.

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Glossary

Soft robotics

The RoboSoft Community defines soft robots as “soft robots/devices that can actively interact with the environment and can undergo ‘large’ deformations relying on inherent or structural compliance”.

Embodied intelligence

Part of control and intelligence contributed by the physical body and its interaction with the environment and the task.

Hyperelastic

Hyperelastic materials are models of material that have a nonlinear elastic response. They are commonly used to approximate soft tissues exhibiting large deformations, including rubber material and biological tissues.

Lagrange multipliers

A method to solve a constrained optimization problem, that is, to find the minima or maxima of a function under equality constraints. The method can be generalized to inequality constraints by the Karush–Kuhn–Tucker conditions.

Anisotropy

The property of exhibiting different characteristics along different directions.

Finite element method

(FEM). A popular numerical method to solve partial differential equations. It reduces the original differential system into a solvable algebraic system by discretizing the domain of interest (time and space) into finite elements.

Lie group

A mathematical set that is differentiable and closed under a product operation. The Lie groups of 3D rotations (SO(3)) and 3D rigid motions (SE(3)) are particularly important here.

Euler angles

A triplet of angles that parametrize a 3D rotation. Each angle represents an elementary rotation around the x, y or z axis.

Non-Newtonian fluids

A fluid whose viscosity depends on stress, thereby breaking Newton’s law of viscosity.

Open-loop control

A control is called open-loop (or feedforward) when the controller operates independently from the output of the system. An example is a heating system controlled only by a timer to switch on or off. Conversely, control is closed-loop (or feedback) when the controller operates by using the output of the system as input to determine its behaviour. An example is a heating system using a controller that senses the temperature of the room.

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Mengaldo, G., Renda, F., Brunton, S.L. et al. A concise guide to modelling the physics of embodied intelligence in soft robotics. Nat Rev Phys 4, 595–610 (2022). https://doi.org/10.1038/s42254-022-00481-z

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