A Learnt Approach for the Design of Magnetically Actuated Shape Forming Soft Tentacle Robots

Soft continuum robots have the potential to revolutionize minimally invasive surgery. The challenges for such robots are ubiquitous; functioning within sensitive, unstructured and convoluted environments which are inconsistent between patients. As such, there exists an open design problem for robots of this genre. Research currently exists relating to the design considerations of on-board actuated soft robots such as fluid and tendon driven manipulators. Magnetically reactive robots, however, exhibit off-board actuation and consequently demonstrate far greater potential for miniaturization and dexterity. In this letter we present a soft, magnetically actuated, slender, shape forming ‘tentacle-like’ robot. To overcome the associated design challenges we also propose a novel design methodology based on a Neural Network trained using Finite Element Simulations. We demonstrate how our design approach generates static, two-dimensional tentacle profiles under homogeneous actuation based on predefined, desired deformations. To demonstrate our learnt approach, we fabricate and actuate candidate tentacles of 2 mm diameter and 42 mm length producing shape profiles within 8% mean absolute percentage error of desired shapes. With this proof of concept, we make the first step towards showing how tentacles with bespoke magnetic profiles may be designed and manufactured to suit specific anatomical constraints.

[1]  Metin Sitti,et al.  A 5-D Localization Method for a Magnetically Manipulated Untethered Robot Using a 2-D Array of Hall-Effect Sensors , 2016, IEEE/ASME Transactions on Mechatronics.

[2]  Jiwon Kim,et al.  Bridging finite element and machine learning modeling: stress prediction of arterial walls in atherosclerosis. , 2019, Journal of biomechanical engineering.

[3]  Sarthak Misra,et al.  Real-time three-dimensional flexible needle tracking using two-dimensional ultrasound , 2013, 2013 IEEE International Conference on Robotics and Automation.

[4]  Shawn A. Chester,et al.  Printing ferromagnetic domains for untethered fast-transforming soft materials , 2018, Nature.

[5]  Samy F. M. Assal,et al.  Motion Planning for Continuum Robots: A Learning from Demonstration Approach , 2018, 2018 27th IEEE International Symposium on Robot and Human Interactive Communication (RO-MAN).

[6]  Stefanie Speidel,et al.  Learning soft tissue behavior of organs for surgical navigation with convolutional neural networks , 2019, International Journal of Computer Assisted Radiology and Surgery.

[7]  Robert J. Webster,et al.  Guiding Elastic Rods With a Robot-Manipulated Magnet for Medical Applications , 2017, IEEE Transactions on Robotics.

[8]  Weihua Li,et al.  A state-of-the-art review on magnetorheological elastomer devices , 2014 .

[9]  Sarthak Misra,et al.  Flexible Instruments for Endovascular Interventions: Improved Magnetic Steering, Actuation, and Image-Guided Surgical Instruments , 2018, IEEE Robotics & Automation Magazine.

[10]  K. Hausegger,et al.  Complications in endoluminal repair of abdominal aortic aneurysms. , 2001, European journal of radiology.

[11]  Xuanhe Zhao,et al.  Ferromagnetic soft continuum robots , 2019, Science Robotics.

[12]  David Wingate,et al.  Learning nonlinear dynamic models of soft robots for model predictive control with neural networks , 2018, 2018 IEEE International Conference on Soft Robotics (RoboSoft).

[13]  Anansa S. Ahmed,et al.  Morphing Soft Magnetic Composites , 2012, Advanced materials.

[14]  Arianna Menciassi,et al.  A soft multi-module manipulator with variable stiffness for minimally invasive surgery , 2017, Bioinspiration & biomimetics.

[15]  D. Caleb Rucker,et al.  Statics and Dynamics of Continuum Robots With General Tendon Routing and External Loading , 2011, IEEE Transactions on Robotics.

[16]  Pietro Valdastri,et al.  Enhanced real-time pose estimation for closed-loop robotic manipulation of magnetically actuated capsule endoscopes , 2018, Int. J. Robotics Res..

[17]  Metin Sitti,et al.  Shape-programmable magnetic soft matter , 2016, Proceedings of the National Academy of Sciences.

[18]  Jaydev P. Desai,et al.  Toward the Development of a Flexible Mesoscale MRI-Compatible Neurosurgical Continuum Robot , 2017, IEEE Transactions on Robotics.

[19]  Xuanhe Zhao,et al.  Mechanics of hard-magnetic soft materials , 2019, Journal of the Mechanics and Physics of Solids.

[20]  Pietro Valdastri,et al.  Adaptive Dynamic Control for Magnetically Actuated Medical Robots , 2019, IEEE Robotics and Automation Letters.

[21]  Sarthak Misra,et al.  Steering of Multisegment Continuum Manipulators Using Rigid-Link Modeling and FBG-Based Shape Sensing , 2016, IEEE Transactions on Robotics.

[22]  S. Misra,et al.  Multi-Core Optical Fibers With Bragg Gratings as Shape Sensor for Flexible Medical Instruments , 2019, IEEE Sensors Journal.

[23]  Bradley J. Nelson,et al.  Magnetic control of continuum devices , 2017, Int. J. Robotics Res..

[24]  Tianqi Xu,et al.  Millimeter-scale flexible robots with programmable three-dimensional magnetization and motions , 2019, Science Robotics.

[25]  Robert J. Webster,et al.  Design and Kinematic Modeling of Constant Curvature Continuum Robots: A Review , 2010, Int. J. Robotics Res..

[26]  Nicolas Andreff,et al.  A Multisegment Electro-Active Polymer Based Milli-Continuum Soft Robots , 2018, 2018 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS).

[27]  Sarthak Misra,et al.  The ARMM System - Autonomous Steering of Magnetically-Actuated Catheters: Towards Endovascular Applications , 2020, IEEE Robotics and Automation Letters.

[28]  A. K. Hoshiar,et al.  A Magnetically Controlled Soft Microrobot Steering a Guidewire in a Three-Dimensional Phantom Vascular Network , 2019, Soft robotics.

[29]  Metin Sitti,et al.  Small-scale soft-bodied robot with multimodal locomotion , 2018, Nature.

[30]  Pietro Valdastri,et al.  Autonomous Retroflexion of a Magnetic Flexible Endoscope , 2017, IEEE Robotics and Automation Letters.

[31]  Howie Choset,et al.  Continuum Robots for Medical Applications: A Survey , 2015, IEEE Transactions on Robotics.

[32]  G. Litynski,et al.  Laparoscopy - The Early Attempts: Spotlighting Georg Kelling and Hans Christian Jacobaeus , 1997, JSLS : Journal of the Society of Laparoendoscopic Surgeons.

[33]  Pietro Valdastri,et al.  Intelligent magnetic manipulation for gastrointestinal ultrasound , 2019, Science Robotics.

[34]  Jake J. Abbott,et al.  First demonstration of simultaneous localization and propulsion of a magnetic capsule in a lumen using a single rotating magnet , 2017, 2017 IEEE International Conference on Robotics and Automation (ICRA).

[35]  Sylvain Martel,et al.  Using the fringe field of a clinical MRI scanner enables robotic navigation of tethered instruments in deeper vascular regions , 2019, Science Robotics.

[36]  Pietro Valdastri,et al.  Toward Autonomous Robotic Colonoscopy: Motion Strategies for Magnetic Capsule Navigation , 2018, 2018 IEEE International Conference on Cyborg and Bionic Systems (CBS).

[38]  David Rubin,et al.  Introduction to Continuum Mechanics , 2009 .