University of Wollongong Research Online Faculty of Engineering and Information Faculty of Engineering and Information Sciences - Papers: Part B Sciences 2019 3D Printable Linear Soft Vacuum Actuators: Their Modeling, Performance Quantification and Application in Soft Robotic Systems Charbel Tawk University of Wollongong, [email protected] Geoffrey M. Spinks University of Wollongong, [email protected] Marc in het Panhuis University of Wollongong, [email protected] Gursel Alici University of Wollongong, [email protected] Follow this and additional works at: https://ro.uow.edu.au/eispapers1 Part of the Engineering Commons, and the Science and Technology Studies Commons Recommended Citation Tawk, Charbel; Spinks, Geoffrey M.; in het Panhuis, Marc; and Alici, Gursel, "3D Printable Linear Soft Vacuum Actuators: Their Modeling, Performance Quantification and Application in Soft Robotic Systems" (2019). Faculty of Engineering and Information Sciences - Papers: Part B. 3375. https://ro.uow.edu.au/eispapers1/3375 Research Online is the open access institutional repository for the University of Wollongong. For further information contact the UOW Library: [email protected] 3D Printable Linear Soft Vacuum Actuators: Their Modeling, Performance Quantification and Application in Soft Robotic Systems Abstract Conventional robotic systems have proved their versatility in the industry where complex tasks requiring high force, high speed and high precision are desired. However, these rigid-bodied systems cannot collaborate safely with humans. Soft robots which are primarily made of highly compliant materials bring robots and humans together by operating safely in unstructured environments. Soft robots demand dexterous soft actuators that preserve or enhance their softness and safety features. This article reports on modeling, performance quantification, and soft oboticr applications of directly three-dimensional (3-D) printed linear soft vacuum actuators (LSOVA), that are manufactured in a single step, using a low-cost and affordable open-source fused deposition modeling 3-D printer. Numerical and experimental results presented show that LSOVA have multiple advantages including high bandwidth (~6.49 Hz), high output force (~27 N) and long lifetime (~21 500 cycles). LSOVA blocked force and linear stroke can be predicted accurately using finite element and analytical models. urF thermore, LSOVA are scalable. The soft actuators can be either assembled in parallel as a bundle, where a linear relationship exists between the number of actuators and the output force or can be scaled up in terms of internal volume where a linear relationship exists between the output force and the internal volume of a single actuator. Finally, LSOVAs were tailored for various robotic applications including soft crawling robots for navigation in tubular systems, soft parallel manipulators for pick and place tasks, soft artificial muscles, soft prosthetic fingers for prosthetic hands, and soft adaptive grippers for gripping applications. Disciplines Engineering | Science and Technology Studies Publication Details Tawk, C., Spinks, G. M., in het Panhuis, M. & Alici, G. (2019). 3D Printable Linear Soft Vacuum Actuators: Their Modeling, Performance Quantification and Application in Soft Robotic Systems. IEEE/ASME Transactions on Mechatronics, 24 (5), 2118-2129. This journal article is available at Research Online: https://ro.uow.edu.au/eispapers1/3375 IEEE/ASME Transactions on Mechatronics 24 (5), 2118 – 2129, 2019. 1 3D Printable Linear Soft Vacuum Actuators (LSOVA): their modeling, performance quantification and application in soft robotic systems Charbel Tawk, Geoffrey M. Spinks, Marc in het Panhuis, and Gursel Alici* One main drawback of these conventional robots is their Abstract—Conventional robotic systems have proved their inability to operate alongside humans. These robotic systems versatility in the industry where complex tasks requiring high are made of rigid materials and components that make them force, high speed and high precision are desired. However, these unsafe to operate in unstructured environments [2]. To extend rigid-bodied systems cannot collaborate safely with humans. Soft robots which are primarily made of highly compliant materials the robot applications beyond classical automation tasks to bring robots and humans together by operating safely in tasks requiring interaction between the robots and their unstructured environments. Soft robots demand dexterous soft operation environments, it is essential to have a safe and actuators that preserve or enhance their softness and safety conforming interaction between robots and humans. Soft robots features. This work reports on modeling, performance which are made of highly compliant and deformable materials quantification and soft robotic applications of directly 3D printed are a tangible solution to bringing robots and humans closer as linear soft vacuum actuators (LSOVA), that are manufactured in a single step, using a low-cost and affordable open-source fused task partners since soft robots are purposefully designed to deposition modeling 3D printer. Numerical and experimental operate in unstructured environments. Soft robots are inspired results presented show that LSOVA have multiple advantages by soft biological structures such as octopus arms, squid including high bandwidth (~6.49Hz), high output force (~27N) and tentacles, elephant trunk and worms [3]. Ideally, a soft robot long lifetime (~21,500 cycles). LSOVA blocked force and linear should be made primarily of soft materials where the stroke can be predicted accurately using finite element and mechanical structure, actuators, sensors, power source and analytical models. Furthermore, LSOVA are scalable. The soft actuators can be either assembled in parallel as a bundle, where a electronics are compliant and deformable, and if possible, they linear relationship exists between the number of actuators and the should be incorporated seamlessly in the same continuum body. output force or can be scaled up in terms of internal volume where However, it is very challenging to develop such soft robots that a linear relationship exists between the output force and the incorporate all these features and still provide useful internal volume of a single actuator. Finally, LSOVAs were performances. tailored for various robotic applications including soft crawling Establishing the soft actuation concept and its realization is robots for navigation in tubular systems, soft parallel manipulators for pick and place tasks, soft artificial muscles, soft the first and most important step in building a soft robot. Soft prosthetic fingers for prosthetic hands and soft adaptive grippers robotic systems demand dexterous soft actuators which can for gripping applications. facilitate the soft and adaptive interaction between the robots and their environments. Therefore, significant research efforts Index Terms—artificial muscle, gripper, manipulator, have recently been dedicated to developing soft actuators and prosthetics, soft robotics, soft actuator. artificial muscles that can be used to articulate soft robots. To this aim, smart materials and structures such as shape memory I. INTRODUCTION alloys [4−8], dielectric elastomers [9,10], ionic polymer-metal OBOTS are becoming smarter and more capable of composites [11], coiled polymer fibers [12,13], hydrogels R performing complex tasks due to recent technological [14,15], humidity-responsive materials [16] and magnetic advancements. These smart systems are widely used in the responsive structures [17] have been used to establish actuation industries that rely on repetitive and laborious tasks involving concepts for soft robots. Chemical reactions such as combustion high precision, high accuracy, large forces and high speeds [1]. [18], electrolysis [19] and catalytic reactions [20] have been This research has been supported by ARC Centre of Excellence for G. M. Spinks ([email protected]) is with the Intelligent Polymer Electromaterials Science (Grant No. CE140100012) and the University of Research Institute, ARC Centre of Excellence for Electromaterials Science, Wollongong, Australia. University of Wollongong, AIIM Facility, NSW, 2522, Australia. Charbel Tawk ([email protected]), G. Alici (*Corresponding Author, M. in het Panhuis ([email protected]) is with the Soft Materials Group, [email protected].), are with School of Mechanical, Materials, Mechatronic School of Chemistry and Intelligent Polymer Research Institute, ARC Centre and Biomedical Engineering, and ARC Centre of Excellence for of Excellence for Electromaterials Science, University of Wollongong, AIIM Electromaterials Science, University of Wollongong, AIIM Facility, NSW, Facility, NSW, 2522, Australia. 2522, Australia. IEEE/ASME Transactions on Mechatronics 24 (5), 2118 – 2129, 2019. 2 integrated within soft robots and soft structures as energy supply of vacuum, after failure where their performance is not sources to drive them. Phase-change materials such as water affected by minor air leaks or structural damage. Finally, the [21] and wax [22] were also embedded in soft robotic systems LSOVA can be used in different robotic applications such as to generate internal pressures. Soft structures coupled with soft navigation robots, soft parallel manipulators, soft artificial tendons and driven by electric motors have also been used to muscles, soft prosthetics and soft adaptive grippers. develop underactuated and adaptive soft grippers [23,24].