隨著科技的發展，柔性機器人在自動化產業上受到關注，比剛性機器人靈活，也更加安全，並可以避免在操作過程中破壞物件或傷及作業人員。藉由不同實驗得知柔性夾爪的非線性運動，並透過PMDH表中的參數、函數來研究柔性夾爪的柔性運動，因此可以估算各種柔性夾爪彎曲量。本文利用3D列印技術與熱塑性聚氨酯（TPU）材質製成氣動柔性手指，經由機構設計，氣動柔性夾爪在填充氣壓過程中較不會漏氣。在柔性手指研發時，透過影像視覺進行手指彎曲角度分析，進一步研發影像視覺辨識系統，用於辨識物件的形狀、方向與位置，且讓柔性夾爪能正確夾取隨意放置在工作平台上的待夾物件。然而，在柔性夾爪與物件之間還沒有任何感測功能，難以確定在夾取物件時，抓力是否足夠。
本文研究了一種新型氣動柔性手指設計，該設計在每個手指尖處嵌埋了石墨烯壓電感測器（Graphene-based Piezoelectric Sensors ,GPS）。 GPS是石墨烯和聚偏二氟乙烯（PVDF）的混合物。石墨烯和PVDF的適當組合以及必要的製備方法會產生β相壓電效應，並可用作觸覺傳感器。製作完成後，石墨烯與PVDF混合物處於液態。將其滴入到3D列印的柔性夾爪溝槽上，等待丙酮（acetone）溶劑揮發、固化。當在GPS上施予壓力時，由於反向壓電效應而產生電訊號，透過最佳化計算出其量測電訊號之最佳斜率，並與市售感測器做比較，最後建立了一個機電整合系統，從GPS獲取電訊號並顯示訊號大小，在實際運用中，我們使用了基於視覺的系統來識別工作平台中物件的形狀和位置，使用機械手臂將氣動柔性夾爪移至物件所在位置，然後透過機電整合系統控制氣壓執行夾握動作，最後將物件夾至指定點位，完成整合指定任務。

Soft robots have drawn great attention from the researchers in the robotics fields. They are more flexible than the rigid robots so they are safer and could prevent damages to the surrounding objects or human during operations. However, the dynamic motions are more difficult to analyze or predict. Since the elastomeric motions of the soft gripper could be studied by the parametrical functions in the PMDH table, one could easily estimate the appropriate the actuation levels for various kinds of soft gripper manipulations. A pneumatic soft finger, made of thermoplastic polyurethane (TPU), was designed and manufactured by 3D printing. The design parameters were properly chosen so that there is no air leakage during pneumatic actuations. During finger development analysis, image vision analyzes finger bending angle, further developed a vision system to identify the shape and orientation of an object and calculated for the most proper way to grip the object using the developed soft gripper. The results of the experiments showed that the developed soft gripper was able to perform proper gripping of the given objects. However, there was not yet any sensing at the interface between the gripper and the object. It was difficult to determine whether the gripping was too tight or too soft.
This paper focused on a new design of pneumatic soft hand that was integrated with the Graphene-based Piezoelectric Sensors (GPS) at the tip of each soft finger. The GPS was a mixture of graphene and polyvinylidene fluoride (PVDF). A proper combination of graphene and PVDF with the necessary preparations developed a beta-phase piezoelectric effect and could be used as tactile sensors. The graphene/PVDF mixture was at the liquid phase after the completion of preparation. Then drop it onto the 3D printed soft finger groove and wait for the acetone solvent to volatilize and solidify. When pressure is applied to the GPS, an electrical signal is generated due to the reverse piezoelectric effect. The best slope of the measured electrical signal is calculated through optimization and compared with commercially available sensors. Finally, the electromechanical integration system obtains the electrical signal from GPS and displays the signal size. In actual application, we use a vision-based system to identify the shape and position of the object in the working platform, and use the robotic arm to move the pneumatic flexible gripper to the position of the object. then use the electromechanical integration system to control the air pressure to perform the gripping action, and finally grip the object to the designated point to complete the designated task of integration.

[1] H. Colson, T. Herman, and N.J., "The lifting and manipu lating of heavy bulky objects " 1945.
[2] N. Rojas, R. R. Ma, and A. M. Dollar, "An Underactuated Hand for Open-Loop In-Hand Planar Manipulation," IEEE TRANSACTIONS ON ROBOTICS, vol. 32, 2016.
[3] J. A. Lessing, R. R. Knopf, D. V. Harburg, and C. E. Vause, "Enhancement of Soft Robotic Grippers Through Integration of Stiff Structures," U.S. Provisional Patent Application, p. 775, 2016.
[4] R. Mutlu, G. Alici, M. i. h. Panhuis, and G. M. Spinks, "3D printed flexure hinges for soft monolithic prosthetic fingers," Soft Robotics, pp. 3 (3), 120-133, 2016.
[5] K.-A. Yang, C.-H. Chuang, Y.-T. Yao, W.-Y. Tan, and P. T. Lin, "Design and Force Estimation of a Cable-Driven Soft Finger," Automation Technology, 2019.
[6] H. Zhang, M. Y. Wang, F. Chen, Y. Wang, A. S. Kumar, and J. Y. H. Fuh, "Design and development of a soft gripper with topology optimization," IEEE, 2017.
[7] 彭瀚旻, 李華峰, 惠耀, 丁慶軍, and 趙淳生, "應用人工肌肉 IPMC 材料的三指微型柔性手爪設計," vol. 30, pp. 347-352, 2010.
[8] 楊凱安, "Manufacturing and Kinematics Analysis of Cable-Driven Soft Mechanisms," 2019.
[9] 劉至行, "智慧型自適性撓性夾爪模組開發與系統整合 (I)," 科技部, 2017. 國立成功大學機械工程學系
[10] L. U. Odhner et al., "A compliant, underactuated hand for robust manipulation," The International Journal of Robotics Research, vol. 33(5), pp. 736-752, 2014.
[11] H. S. Stuart, S. Wang, B. Gardineer, D. L. Christensen, D. M. Aukes, and M. Cutkosky, "A compliant underactuated hand with suction flow for underwater mobile manipulation," IEEE International Conference on Robotics and Automation (ICRA), IEEE, pp. 6691-6697, 2014.
[12] E. Shahabi, W.-H. Lu, P. T. Lin, and C.-H. Kuo, "Computer Vision-Based Object Recognition And Automatic Pneumatic Soft Gripping," ASME, 2019.
[13] E. Shahabi, Y.-T. Yao, C.-H. Chuang, P. T. Lin, and C.-H. Kuo, "Design and Testing of 2-Degree-of-Freedom (DOF) Printable Pneumatic Soft Finger," ISRM, 2019.
[14] A. Girard, J.-P. L. Bigué, B. M. O’Brien, T. A. Gisby, I. A. Anderson, and J.-S. Plante, "Soft two degree of freedom dielectric elastomer position sensor exhibiting line ar behavior," IEEE/ASME Transactions on Mechatronics, vol. 20(1), pp. 105-114, 2015.
[15] V. Slesarenko, S. Engelkemier, P. I. Galich, D. Vladimirsky, G. Klein, and S. Rudykh, "Strategies to Control Performance of 3D-Printed, Cable-Driven Soft Polymer Actuators: From Simple Architectures to Gripper Prototype," polymers, 2018.
[16] Z. Wang, D. S. Chathuranga, and S. Hirai, "3D Printed Soft Gripper for Automatic Lunch Box Packing," IEEE International Conference on Robotics and Biomimetics, 2016.
[17] J. Shintake, S. Rosset, B. Schubert, D. Floreano, and H. Shea, "Versatile Soft Grippers with Intrinsic Electroadhesion Based on Multifunctional Polymer Actuators," Material Views, 2016.
[18] S. Li et al., "A Vacuum-driven Origami “Magic-ball” Soft Gripper," International Conference on Robotics and Automation (ICRA), 2019.
[19] B. S. Homberg, R. K. Katzschmann, M. R. Dogar, and D. Rus, "Haptic Identification of Objects using a Modular Soft Robotic Gripper," IEEE, pp. 1698-1705, 2015.
[20] J. Zhou, S. Chen, and Z. Wang, "A Soft-Robotic Gripper With Enhanced Object Adaptation and Grasping Reliability," IEEE ROBOTICS AND AUTOMATION LETTERS, vol. 2, NO. 4, 2017.
[21] Z. Wang, Y. Torigoe, and S. Hirai, "A Prestressed Soft Gripper: Design, Modeling, Fabrication, and Tests for Food Handling," IEEE ROBOTICS AND AUTOMATION LETTERS, vol. 2, NO. 4, 2017.
[22] ANSYS Inc. (2017). ANSYS Fluent Tutorial Guide. Available: https://www.ansys.com/
[23] A. K. Geim, "Graphene：status and prospects," science, vol. 324(5934), pp. 1530-1534, 2009.
[24] M. A. Rahman and G. S. Chung, "Synthesis of PVDF-graphene nanocomposites and their properties.," Journal of Alloys and Compounds, vol. 581, pp. 724-730, 2013.
[25] 陳冠霖, "探討Graphene-TiO2/PVDF中空纖維膜之光、電催化效應對染料溶液降解之影響," 2016.
[26] 黃琮翰, "智能壓電薄膜之壓力感測系統開發並應用於沖床模具之壽命評估," 2019.
[27] FlashForge. FlashForge 3D Printer Creater Pro. Available: https://www.flashforge.com/consumer/detail/Creator%20Pro?id=4
[28] Diabase engineering Installation Instructions for Replicator-style Printers. Available: https://flexionextruder.com/support/dual-extruder-installation/
[29] National Instruments. NI-9234. Available: https://www.ni.com/zh-tw/support/model.ni-9234.html
[30] ARIAT TECHNOLOGY LIMITED. (1996). Available: https://www.ariat-tech.tw/
[31] 聚英電子工業互聯網方案提供商. (2007). Available: https://www.juyingele.com.cn/product/ioModules/AI/910.html
[32] 高鹿興業有限公司. (1980). Available: https://www.genndih.com/cht/%E5%A3%93%E5%8A%9B%E9%9B%BB%E6%B0%A3%E6%AF%94%E4%BE%8B%E9%96%A5/%E9%AB%98%E5%A3%93%E5%A3%93%E5%8A%9B%E6%AF%94%E4%BE%8B%E9%96%A5-0-120psi.html
[33] HIWIN. Information of RT605-710-GB Robot. Available: https://www.hiwin.tw/products/mar/articulated/rt605/rt605_710_gb.aspx
[34] D. Rus and M. T. Tolley, "Design, fabrication and control of soft robots," Nature, vol. 521, p. 467, 2015.
[35] M. Biron, Thermoplastics and Thermoplastic Composites, 2012.11 ed. pp. 682-684.
[36] Stratasys Ltd. FDM TPU 92A. Available: https://www.stratasys.com/materials/search/fdm-tpu-92a
[37] 上禾伸企業有限公司. TPU (Thermoplastic polyurethane)熱可塑性聚氨酯彈性體. Available: https://www.good-plastics.com/products/90-2016-01-12-12-40-52/134-tpu
[38] Covestro Solution Center. Technology Mechanical properties. Available: https://solutions.covestro.com/en/highlights/articles/theme/product-technology/mechanical-properties-tpu
[39] R. Sabelli, S. Mahin, and C. Chang, "Seismic demands on steel braced frame buildings with bucklingrestrained braces," 2003. Elsevier Science Ltd.
[40] 吳載根, 線上自動光學檢測(AOI)系統 In-Line Automatic Optical Inspection (AOI) System. 2019.