A novel shape memory alloy actuated soft gripper imitated hand behavior

Abstract

The limited length shrinkage of shape memory alloy (SMA) wire seriously limits the motion range of SMA-based gripper. In this paper, a new soft finger without silicone gel was designed based on pre bent SMA wire, and the finger was back to its original shape by heating SMA wire, rather than relying only on heat exchange with the environment. Through imitating palm movement, a structure with adjustable spacing between fingers was made using SMA spring and rigid spring. The hook structure design at the fingertip can form self-locking to further improve the load capacity of gripper. Through the long thin rod model, the relationship of the initial pre bent angle on the bending angle and output force of the finger was analyzed. The stress-strain model of SMA spring was established for the selection of rigid spring. Three grasping modes were proposed to adapt to the weight of the objects. Through the test of the gripper, it was proved that the gripper had large bending amplitude, bending force, and response rate. The design provides a new idea for the lightweight design and convenient design of soft gripper based on SMA.

Graphical abstract

Keywords

shape memory alloy (SMA) / pre bent / wire / gripper / grasping mode / lightweight

References

[1] Shintake J , Cacucciolo V , Floreano D , Shea H . Soft robotic grippers. Advanced Materials, 2018, 30(29): 1707035

[2] Brown E , Rodenberg N , Amend J , Mozeika A , Steltz E , Zakin M R , Lipson H , Jaeger H M . Universal robotic gripper based on the jamming of granular material. Proceedings of the National Academy of Sciences of the United States of America, 2010, 107(44): 18809–18814

[3] Jung G P , Koh J S , Cho K J . Underactuated adaptive gripper using flexural buckling. IEEE Transactions on Robotics, 2013, 29(6): 1396–1407

[4] Qian X J , Chen Q M , Yang Y , Xu Y S , Li Z , Wang Z H , Wu Y H , Wei Y , Ji Y . Untethered recyclable tubular actuators with versatile locomotion for soft continuum robots. Advanced Materials, 2018, 30(29): 1801103

[5] Laschi C , Cianchetti M , Mazzolai B , Margheri L , Follador M , Dario P . Soft robot arm inspired by the octopus. Advanced Robotics, 2012, 26(7): 709–727

[6] Xie Z X , Domel A G , An N , Green C , Gong Z Y , Wang T M , Knubben E M , Weaver J C , Bertoldi K , Wen L . Octopus arm-inspired tapered soft actuators with suckers for improved grasping. Soft Robotics, 2020, 7(5): 639–648

[7] Glick P , Suresh S A , Ruffatto D , Cutkosky M , Tolley M T , Parness A . A soft robotic gripper with gecko-inspired adhesive. IEEE Robotics and Automation Letters, 2018, 3(2): 903–910

[8] Ilievski F , Mazzeo A D , Shepherd R F , Chen X , Whitesides G M . Soft robotics for chemists. Angewandte Chemie International Edition, 2011, 50(8): 1890–1895

[9] Manti M , Hassan T , Passetti G , D’Elia N , Laschi C , Cianchetti M . A bioinspired soft robotic gripper for adaptable and effective grasping. Soft Robotics, 2015, 2(3): 107–116

[10] Roche E T , Wohlfarth R , Overvelde J T B , Vasilyev N V , Pigula F A , Mooney D J , Bertoldi K , Walsh C J . A bioinspired soft actuated material. Advanced Materials, 2014, 26(8): 1200–1206

[11] Li S G , Vogt D M , Rus D , Wood R J . Fluid-driven origami-inspired artificial muscles. Proceedings of the National Academy of Sciences of the United States of America, 2017, 114(50): 13132–13137

[12] Martens M , Boblan I . Modeling the static force of a festo pneumatic muscle actuator: a new approach and a comparison to existing models. Actuators, 2017, 6(4): 33

[13] Gu G Y , Zou J , Zhao R K , Zhao X H , Zhu X Y . Soft wall-climbing robots. Science Robotics, 2018, 3(25): eaat2874

[14] Jain R K , Datta S , Majumder S . Design and control of an IPMC artificial muscle finger for micro gripper using EMG signal. Mechatronics, 2013, 23(3): 381–394

[15] Sun Q M , Han J Z , Li H , Liu S , Shen S N , Zhang Y F , Sheng J Z . A miniature robotic turtle with target tracking and wireless charging systems based on IPMCs. IEEE Access, 2020, 8: 187156–187164

[16] Wang Y Z , Gupta U , Parulekar N , Zhu J . A soft gripper of fast speed and low energy consumption. Science China Technological Sciences, 2019, 62(1): 31–38

[17] Li G R , Chen X P , Zhou F H , Liang Y M , Xiao Y H , Cao X N , Zhang Z , Zhang M Q , Wu B S , Yin S Y , Xu Y , Fan H B , Chen Z , Song W , Yang W J , Pan B B , Hou J Y , Zou W F , He S P , Yang X X , Mao G Y , Jia Z , Zhou H F , Li T F , Qu S X , Xu Z B , Huang Z L , Luo Y W , Xie T , Gu J , Zhu S Q , Yang W . Self-powered soft robot in the Mariana Trench. Nature, 2021, 591(7878): 66–71

[18] Kellaris N , Gopaluni Venkata V , Smith G M , Mitchell S K , Keplinger C . Peano-HASEL actuators: muscle-mimetic, electrohydraulic transducers that linearly contract on activation. Science Robotics, 2018, 3(14): eaar3276

[19] Gao F , Wang Z L , Wang Y K , Wang Y W , Li J . A prototype of a biomimetic mantle jet propeller inspired by cuttlefish actuated by SMA wires and a theoretical model for its jet thrust. Journal of Bionics Engineering, 2014, 11(3): 412–422

[20] Firouzeh A , Salerno M , Paik J . Stiffness control with shape memory polymer in underactuated robotic origamis. IEEE Transactions on Robotics, 2017, 33(4): 765–777

[21] Jin H , Dong E B , Xu M , Liu C S , Alici G , Jie Y . Soft and smart modular structures actuated by shape memory alloy (SMA) wires as tentacles of soft robots. Smart Materials and Structures, 2016, 25(8): 085026

[22] Linghu C H , Zhang S , Wang C J , Yu K X , Li C L , Zeng Y J , Zhu H D , Jin X H , You Z Y , Song J Z . Universal SMP gripper with massive and selective capabilities for multiscaled, arbitrarily shaped objects. Science Advances, 2020, 6(7): eaay5120

[23] Zhuo S Y , Zhao Z G , Xie Z X , Hao Y F , Xu Y C , Zhao T Y , Li H J , Knubben E M , Wen L , Jiang L , Liu M J . Complex multiphase organohydrogels with programmable mechanics toward adaptive soft-matter machines. Science Advances, 2020, 6(5): eaax1464

[24] Zhang S , Ke X X , Jiang Q , Ding H , Wu Z G . Programmable and reprocessable multifunctional elastomeric sheets for soft origami robots. Science Robotics, 2021, 6(53): eabd6107

[25] Wang H Z , Chen S , Li H W , Chen X Z , Cheng J S , Shao Y L , Zhang C L , Zhang J , Fan L L , Chang H , Guo R , Wang X L , Li N , Hu L , Wei Y , Liu J . A liquid gripper based on phase transitional metallic ferrofluid. Advanced Functional Materials, 2021, 31(32): 2100274

[26] Nah S K , Zhong Z W . A microgripper using piezoelectric actuation for micro-object manipulation. Sensors and Actuators A: Physical, 2007, 133(1): 218–224

[27] Kim J , Kim J W , Kim H C , Zhai L D , Ko H U , Muthoka R M . Review of soft actuator materials. International Journal of Precision Engineering and Manufacturing, 2019, 20(12): 2221–2241

[28] Wang M F , Dong X , Ba W M , Mohammad A , Axinte D , Norton A . Design, modelling and validation of a novel extra slender continuum robot for in-situ inspection and repair in aeroengine. Robotics and Computer-Integrated Manufacturing, 2021, 67: 102054

[29] Yang C H , Geng S N , Walker I , Branson D T , Liu J G , Dai J S , Kang R J . Geometric constraint-based modeling and analysis of a novel continuum robot with shape memory alloy initiated variable stiffness. The International Journal of Robotics Research, 2020, 39(14): 1620–1634

[30] Lu Y F , Xie Z J , Wang J , Yue H B , Wu M , Liu Y W . A novel design of a parallel gripper actuated by a large-stroke shape memory alloy actuator. International Journal of Mechanical Sciences, 2019, 159: 74–80

[31] Wang W , Ahn S H . Shape memory alloy-based soft gripper with variable stiffness for compliant and effective grasping. Soft Robotics, 2017, 4(4): 379–389

[32] Yin H B , Kong C , Li J F , Yang G L . Modeling of grasping force for a soft robotic gripper with variable stiffness. Mechanism and Machine Theory, 2018, 128: 254–274

[33] Lee J H , Chung Y S , Rodrigue H . Application of SMA spring tendons for improved grasping performance. Smart Materials and Structures, 2019, 28(3): 035006

[34] Shi Z Y , Pan J , Tian J W , Huang H , Jiang Y R , Zeng S . An inchworm-inspired crawling robot. Journal of Bionics Engineering, 2019, 16(4): 582–592

[35] Pan J , Shi Z Y , Wang T M . Variable-model SMA-driven spherical robot. Science China Technological Sciences, 2019, 62(8): 1401–1411

[36] DYNALLOY. Introduction to FLEXINOL^® Actuator Wire. Available from DYNALLOY website, 2022

[37] Murphy J G . The stability of thin, stretched and twisted elastic rods. International Journal of Non-Linear Mechanics, 2015, 68: 96–100

[38] Manning R S , Hoffman K A . Stability of n-covered circles for elastic rods with constant planar intrinsic curvature. Journal of Elasticity and the Physical Science of Solids, 2001, 62(1): 1–23

RIGHTS & PERMISSIONS

Higher Education Press