Article
Automation & Control Systems
Jin Sun, Dong Zhou, Jie Deng, Yingxiang Liu
Summary: This article proposes an intersected twisted artificial muscle unit (ITAMU) to achieve a large contraction ratio, which is used to drive the developed soft pump, and characteristics of high flow rate and no noise pollution are achieved. The configuration and principle of the ITAMU and the soft pump are depicted. The contraction ratio of ITAMU and the flow rate of the soft pump are theoretically calculated, and the prototypes are manufactured and tested. The results show that the maximum contraction ratio of ITAMU reaches 41.2%, and the output force is 3.27 N. The experiments on the flow rate and pressure of the soft pump indicate that the maximum flow rate is 680 mL/min, and the pressure reaches 2.3 kPa. In conclusion, the proposed soft pump exhibits a high flow rate, showing its application prospect in the field of soft exploration robots.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2023)
Review
Chemistry, Multidisciplinary
Xueqi Leng, Guangkai Mei, Guanghao Zhang, Zunfeng Liu, Xiang Zhou
Summary: Twisted-fiber artificial muscles, as a new type of soft actuator, have great potential for lightweight smart devices and soft robotics. They generate internal torque and exhibit rotation, contraction, or elongation through fiber twisting. Preserving the torque during actuation is crucial for reversible and stable artificial muscle performance, but this issue has not been systematically discussed. This review summarizes the mechanisms for preserving torque in twisted fibers and discusses potential applications, challenges, and future directions for research.
CHEMICAL SOCIETY REVIEWS
(2023)
Article
Chemistry, Multidisciplinary
Dezhi Yang, Miao Feng, Guoying Gu
Summary: This work proposes a class of lightweight fabric-lattice artificial muscles (FAMs) that can be pneumatically actuated with large contraction ratios and considerable output forces. These FAMs can be configured for various high-performance soft robotic applications, such as powerful robotic elbow, assistive shoulder exosuit, and adaptive soft gripper.
ADVANCED MATERIALS
(2023)
Article
Physics, Applied
Caterina Lamuta
Summary: Lightweight and single-component artificial muscles, especially Highly Twisted Artificial Muscles (HTAMs), show great potential as alternative actuators for various applications. However, there is a lack of awareness in the scientific community regarding the progress, challenges, and limitations of HTAMs. This Perspective paper provides a comprehensive overview of the working mechanism, manufacturing, modeling, and applications of HTAMs, aiming to encourage transformative research in this field.
APPLIED PHYSICS LETTERS
(2023)
Article
Multidisciplinary Sciences
Xiaoyu Hu, Jiatian Li, Sitong Li, Guanghao Zhang, Run Wang, Zhongsheng Liu, Mengmeng Chen, Wenqian He, Kaiqing Yu, Wenzhong Zhai, Weiqiang Zhao, Abdul Qadeer Khan, Shaoli Fang, Ray H. Baughman, Xiang Zhou, Zunfeng Liu
Summary: This paper reports an artificial muscle controlled by thermodynamic-twist coupling, which can be used in different actuation modes, such as elongation, contraction, and torsional rotation. It provides a new design strategy for intelligent materials.
NATIONAL SCIENCE REVIEW
(2023)
Article
Engineering, Electrical & Electronic
Dharshika Kongahage, Geoffrey M. Spinks, Javad Foroughi
Summary: This study presents experimental observations of polymer actuators fabricated with multiple yarns, and critically analyzes the reasons for decreased performance with increasing number of yarns. The findings demonstrate that even a minor change in fiber length can significantly affect the stroke and force values of twisted polymer actuators.
SENSORS AND ACTUATORS A-PHYSICAL
(2021)
Article
Physics, Multidisciplinary
Andrea Fontanella, Juan Miguel Nieto Garcia
Summary: In this article, classical closed string solutions to the non-relativistic AdS(5) x S-5 string theory are found, which are analogous to the BMN and GKP solutions in the relativistic theory. It is shown that the non-relativistic AdS(5) x S-5 string theory possesses a Z(2) orbifold symmetry, allowing the imposition of twisted boundary conditions. Among the solutions in the twisted sector, the one related to the semiclassical expansion in arXiv:2102.00008 is identified.
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2022)
Review
Automation & Control Systems
Xueqi Leng, Xiaoyu Hu, Wubin Zhao, Baigang An, Xiang Zhou, Zunfeng Liu
Summary: Artificial muscles are actuators that can contract, extend, or rotate when exposed to external stimuli, with twisted fibers playing a crucial role in the process. This technology holds potential applications in fields such as temperature-regulating clothing, soft robots, prosthetics, and exoskeletons, but also presents both opportunities and challenges.
ADVANCED INTELLIGENT SYSTEMS
(2021)
Article
Engineering, Multidisciplinary
Ye Xiao, Zhao Luo, Chun Li
Summary: Recently-developed twisted multifilament artificial muscles, fabricated by a twist-insertion procedure, store energy and output work under external stimuli. Their energy conversion efficiency, especially for those made of carbon nanotubes, is of great interest due to their impressive tensile stroke, energy density, and controllability. In this paper, numerical simulations are used to model the thermal actuation processes of artificial muscles and analyze the geometric effects of cross-sectional shapes on their tensile properties. The evaluation of work output and energy conversion efficiency provides insights into enhancing the mechanical performance of artificial muscles. The strategies for improvement are also discussed. © 2023 Elsevier Inc. All rights reserved.
APPLIED MATHEMATICAL MODELLING
(2023)
Article
Physics, Multidisciplinary
Erin Morissette, Jiang-Xiazi Lin, Dihao Sun, Liangji Zhang, Song Liu, Daniel Rhodes, Kenji Watanabe, Takashi Taniguchi, James Hone, Johannes Pollanen, Mathias S. Scheurer, Michael Lilly, Andrew Mounce, J. I. A. Li
Summary: Phase transitions in twisted bilayer graphene allow for the characterization of spin and valley couplings, and the observation of collective excitations. These excitations provide information about the electronic order in strongly correlated systems. By using a resistively detected electron spin resonance technique, low-energy collective excitations have been observed near the magic angle. The resonance response is dependent on the strong correlations within the flat moire energy band.
Article
Cell Biology
Marcel Rose, Katrin Domsch, Jakob Bartle-Schultheis, Ingolf Reim, Christoph Schaub
Summary: The genesis of syncytial muscles is typically considered an irreversible developmental process, and the mesodermal master regulator Twist plays a key role in the reprogramming process by regulating the activity of the Hippo pathway effector Yorkie. This study provides evidence that Twist is required for the initiation of syncytial muscle dedifferentiation and fragmentation, and fibroblast growth factor receptor (FGFR) Ras-mitogen-activated protein kinase (MAPK) signaling maintains Twist expression in resulting mononucleated myoblasts.
Article
Robotics
Ryota Kobayashi, Hiroyuki Nabae, Koichi Suzumori
Summary: Tensegrity structures have gained significant attention due to their lightweight, compliant, and flexible properties, which are not commonly found in traditional robots. These structures can be modularized to create soft robots capable of operating in unknown environments, showcasing complex and effective behavior. This study focuses on torsional deformation and presents a novel arrangement method for thin artificial muscles, resulting in a large torsion of +/- 50 deg. Through modularization, a tensegrity arm capable of removing a plastic bottle cap was successfully developed, highlighting the applicability of torsional deformation and the usefulness of structure modularization.
IEEE ROBOTICS AND AUTOMATION LETTERS
(2023)
Article
Chemistry, Physical
Jeet Majumdar, Subhadeep Dasgupta, Soham Mandal, Mohd Moid, Manish Jain, Prabal K. Maiti
Summary: Graphene nanoslit pores are used for various nanofluidic devices, and the rotational misalignment between two parallel graphene sheets can affect the properties of the devices. The structure and dielectric constant of confined water molecules remain unchanged for different twist angles, while the ordering of water molecules shows differences between SPC/E and TIP4P/2005 water models. The friction coefficient of the confined water molecules varies for small twist angles, but becomes independent for twists greater than 5.1°.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Automation & Control Systems
Dong Zhou, Yingxiang Liu, Xintian Tang, Jin Sun, Jie Deng
Summary: Soft robots made from soft materials have advantages in environmental adaptability and motion flexibility, but their load capacity is limited due to their soft body. This article presents a new inchworm driving method using inclined supporting feet and twisted artificial muscle (TAM), which enables a single tensegrity unit to have multi-motion capacity and high load capacity.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2022)
Article
Physics, Condensed Matter
J. W. Zuber, C. Zhang
Summary: The study shows that in twisted bilayer graphene, increasing the twist angle enhances the transverse metallic response, while interlayer transitions lead to a significant increase in the non-zero anomalous Hall conductivity when the Fermi level traverses the gap between the two conduction bands.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Article
Engineering, Industrial
Miguel Vieira, Samuel Moniz, Bruno S. Goncalves, Tania Pinto-Varela, Ana Paula Barbosa-Povoa, Pedro Neto
Summary: In this work, a novel optimisation-simulation methodology based on the Recursive Optimisation-Simulation Approach (ROSA) is developed to provide effective decision-support for integrated production planning and scheduling. Through an industrial case study, the method is shown to generate near-optimal solutions, including batch decision, release schedule of production orders, task allocation to humans or robots, and the number of robots per period.
INTERNATIONAL JOURNAL OF PRODUCTION RESEARCH
(2022)
Article
Materials Science, Multidisciplinary
Alexandre Chambel, Afsaneh L. Sanati, Pedro Alhais Lopes, Timur Nikitin, Rui Fausto, Anibal T. de Almeida, Mahmoud Tavakoli
Summary: The study demonstrates a rapid, low-cost, and scalable method for fabrication of novel electrodes, which can adjust the transparency and conductivity of the films through laser processing, enabling fast production of large-area, complex structured electrodes.
ADVANCED MATERIALS TECHNOLOGIES
(2022)
Review
Materials Science, Multidisciplinary
Carmel Majidi, Kaveh Alizadeh, Yunsik Ohm, Andre Silva, Mahmoud Tavakoli
Summary: Soft polymers embedded with liquid metals like EGaIn exhibit unique combinations of mechanical, electrical, and thermal properties that are not possible with other materials. These composites can be engineered to display mechanical and electrical self-healing properties, high fracture toughness, and resistance to tearing. Additionally, they can function as printable conductive inks when solid filler particles are added. This short review discusses the different classes of EGaIn-polymers composites, materials synthesis, and patterning approaches, and compares their properties to other material systems. It also reviews the applications of these materials in wearable bioelectronics, soft robotics, shape programmable smart materials, as well as energy storage and harvesting devices.
FLEXIBLE AND PRINTED ELECTRONICS
(2022)
Article
Chemistry, Multidisciplinary
Guilherme Costa, Pedro Alhais Lopes, Afsaneh L. Sanati, Andre F. Silva, Marta Calisto Freitas, Anibal T. de Almeida, Mahmoud Tavakoli
Summary: This study introduces a 3D-printed Ag-Ga battery through digital printing of sinter-free composites, resulting in faster printing, self-feeding, and self-aggregation mechanism. The battery exhibits record-breaking areal capacity and excellent stretchability, making it a promising alternative to Ag-Zn batteries. Additionally, printing sensors and batteries on biomonitoring e-textiles allows for simultaneous monitoring of electrocardiography, body temperature, and respiration.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Mahmoud Tavakoli, Pedro Alhais Lopes, Abdollah Hajalilou, Andre F. Silva, Manuel Reis Carneiro, Jose Carvalheiro, Joao Marques Pereira, Anibal T. de Almeida
Summary: This article demonstrates a novel architecture of materials and methods for microchip-integrated condensed soft-matter 3R electronics. The 3R function is enabled by a biphasic liquid metal-based composite, a block copolymer with nonpermanent physical crosslinks, and an electrochemical technique for material recycling. In addition, an autonomous laser-patterning method for scalable circuit patterning is developed. The implementation and recycling of sophisticated skin-mounted patches with embedded sensors, electrodes, antennas, and microchips are also demonstrated.
ADVANCED MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Wuzhou Zu, Yunsik Ohm, Manuel Reis Carneiro, Michael Vinciguerra, Mahmoud Tavakoli, Carmel Majidi
Summary: This study explores improvements to printed conductive materials for stretchable electronics, focusing on the choice of silver flakes and their impact on electrical and electromechanical properties. By using specific silver flakes, high conductivity and strain limit, as well as low electromechanical coupling, can be achieved. The study also demonstrates the applicability of these materials in wearable bioelectronics.
ADVANCED MATERIALS TECHNOLOGIES
(2022)
Article
Engineering, Biomedical
Rita G. Fonseca, Francesco De Bon, Patricia Pereira, Francisca M. Carvalho, Marta Freitas, Mahmoud Tavakoli, Armenio C. Serra, Ana C. Fonseca, Jorge F. J. Coelho
Summary: This study presents highly stretchable and tough hydrogels with controlled light-triggered photo-degradation for the first time. The hydrogels are formed by a double-network structure with covalently and ionically crosslinked subnetworks. By using a novel crosslinker, the mechanical properties of the hydrogel were not affected. The hydrogels show potential applications in health, electronics, and energy due to their excellent mechanical properties and controlled degradation.
MATERIALS TODAY BIO
(2022)
Editorial Material
Chemistry, Multidisciplinary
Antonio Paulo Moreira, Pedro Neto, Felix Vidal
APPLIED SCIENCES-BASEL
(2023)
Article
Nanoscience & Nanotechnology
Epsita Kar, Puja Ghosh, Shewli Pratihar, Mahmoud Tavakoli, Shrabanee Sen
Summary: Researchers have developed a flexible, lightweight, and biocompatible electronic skin with a portable power source using processed chicken feather fiber. The device uses a composite material of chicken feather fiber and organic PVDF polymer, enhancing its piezoelectric properties and biocompatibility. The electronic skin can monitor various human physiological signals with excellent sensitivity, and also serve as a power source for other small electronics.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Nanoscience & Nanotechnology
Michael R. Vinciguerra, Mahmoud Tavakoli, Carmel Majidi, Lining Yao, Dinesh K. Patel, Wuzhou Zu
Summary: This study presents a design and manufacturing methodology for combining direct ink write (DIW) 3D printing of soft, stretchable conductive inks with DIW-based 4D printing of LCE to create fully integrated, electrically responsive, shape programmable matter. The inclusion of conductive ink allows for stable power delivery to surface mount devices and Joule heating traces in a highly dynamic LCE system. This digital fabrication approach can push LCE actuators closer to becoming functional devices, such as shape programmable antennas and actuators with integrated sensing.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Automation & Control Systems
Diogo Fonseca, Mohammad Safeea, Pedro Neto
Summary: This article presents a novel mechanically flexible force and proximity hybrid sensor that is inexpensive and easy to apply on complex-shaped robot structures. The sensor's versatility, flexibility, thinness, accuracy, and repeatability were demonstrated through experimental trials. It was successfully applied in hand-guiding a robot and human-robot collision avoidance.
IEEE TRANSACTIONS ON INDUSTRIAL INFORMATICS
(2023)
Article
Automation & Control Systems
Pedro Matos, Pedro Neto
Summary: This paper presents the design and fabrication of a modular and low-cost 3D-printable robotic gripper that can grasp and hold different objects. It is a parallel gripper with a two-finger two-motor configuration, maximizing grasping force while maintaining compactness. The gripper structure includes three types of fingers: hard, flexible, and soft, and utilizes an embedded camera with computer vision processing for object recognition. Experimental tests show that it can grasp different objects with a maximum force of 76N per finger and millimeter-level positioning accuracy.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2023)
Article
Computer Science, Interdisciplinary Applications
M. Safeea, P. Neto
Summary: Collaborative robots are rapidly growing and being used in various domains, working alongside humans in unstructured environments. Python and Simulink are essential tools for robot design and control algorithm development. This study introduces iiwaPy, a Python library, and SimulinkIIWA, for interfacing KUKA iiwa robots. Both interfaces support robot motion control and state monitoring, and provide open-source code and example applications.
INTERNATIONAL JOURNAL OF COMPUTER INTEGRATED MANUFACTURING
(2023)
Article
Engineering, Industrial
Laura Duarte, Pedro Neto
Summary: This study proposes an action classification system using a Dynamic and Active-pixel Vision Sensor (DAVIS) to recognize primitive assembly tasks from human motion events data. Advanced deep learning and recurrent networks are utilized to classify spatial and temporal features. The proposed filters can remove about 65% of event data noise, achieving a high classification accuracy of up to 99.37% for trained subjects and 97.08% for new subjects.
JOURNAL OF MANUFACTURING SYSTEMS
(2023)
Editorial Material
Robotics
Antonio Paulo Moreira, Pedro Neto, Felix Vidal
Article
Engineering, Mechanical
Antonella Castellano, Pietro Stano, Umberto Montanaro, Marco Cammalleri, Aldo Sorniotti
Summary: This paper proposes a new control strategy for hybrid electric vehicles, called Model Predictive Control (MPC), and considers the losses in transmission gears. Through a case study on Chevrolet Volt, the results show that the simplified internal model has a minor impact on fuel consumption performance.
MECHANISM AND MACHINE THEORY
(2024)
Article
Engineering, Mechanical
Rui Peng, Gregory S. Chirikjian
Summary: This article introduces a method of designing morphable thick-panel origami structures using reconfigurable linkages, which improves the potential of origami techniques for different tasks and solves the limitations of one-DOF and multiple-DOF folding structures.
MECHANISM AND MACHINE THEORY
(2024)
Article
Engineering, Mechanical
Gaohan Zhu, Weizhong Guo, Yinghui Li, Youcheng Han
Summary: Comprehensive and accurate performance evaluation is crucial for profile synthesis and analysis of higher pair mechanisms. This paper proposes evaluation indices and methods for the transmission performance of planar higher pair mechanisms from different perspectives. It subdivides the transmission performance into element-based performance and joint-based performance and develops novel indices specific to higher pair mechanisms. A graphical mapping method based on element-based performance is also proposed for intuitive analysis. Practical examples validate the effectiveness of the proposed indices and methods for evaluating the performance of higher pair mechanisms.
MECHANISM AND MACHINE THEORY
(2024)
Article
Engineering, Mechanical
Ke Wu, Gang Zheng, Guimin Chen, Shorya Awtar
Summary: Researchers proposed a new modeling method, namely Body-frame Beam Constraint Model (BBCM), to predict and optimize the design of high-precision compliant mechanisms (CMs).
MECHANISM AND MACHINE THEORY
(2024)
Article
Engineering, Mechanical
Youcheng Han, Weizhong Guo, Changjie Zhao, Ziyue Li, Ze Fu, Yinghui Li
Summary: This study proposes a structural synthesis methodology that considers motion, force, and energy characteristics simultaneously to design efficient mechanisms.
MECHANISM AND MACHINE THEORY
(2024)
Article
Engineering, Mechanical
Cristian Enrico Capalbo, Daniel De Gregoriis, Tommaso Tamarozzi, Giuseppe Carbone, Domenico Mundo
Summary: This study proposes a novel flexible multibody formulation that enables efficient updating of models while maintaining small size and high accuracy. Numerical validation demonstrates its wide applicability across various materials and mechanisms, showing promising results in terms of accuracy.
MECHANISM AND MACHINE THEORY
(2024)
Article
Engineering, Mechanical
Weihao Zhao, Junbei Liao, Wei Qian, Haoyong Yu, Zhao Guo
Summary: This paper presents a newly designed compliant actuator using a tensile springs array to address the challenges in achieving linear and consistent elastic properties, low friction, minor hysteresis, and good compliance in series elastic actuators (SEA). The unique geometry of the spring array enables the SEA to have consistent rotary stiffness with minimal friction and hysteresis. The device's performance is evaluated using PID and sliding mode control, demonstrating its constant low rotary stiffness and torque tracking bandwidth, making it suitable for human-robot interaction requirements.
MECHANISM AND MACHINE THEORY
(2024)
Article
Engineering, Mechanical
Mohui Jin, Yukang Luo, Xing Xu, Bowei Xie, Weisheng Wang, Zewei Li, Zhou Yang
Summary: This paper presents a method for evaluating the contact interaction between compliant mechanisms and external objects. By establishing a numerical model and introducing contact springs to describe the contact forces, the deformation and normal contact force/stress can be accurately calculated. The static equilibrium configuration and contact force/stress can be obtained by minimizing the total potential energy function of the system.
MECHANISM AND MACHINE THEORY
(2024)
Article
Engineering, Mechanical
Alejandro G. Gallardo, Martin A. Pucheta
Summary: This paper presents a method for the synthesis of parallel flexure systems using Screw Theory and Linear Algebra. The method is validated through three case studies and offers a simple and precise design with decoupled actuators.
MECHANISM AND MACHINE THEORY
(2024)
Article
Engineering, Mechanical
Xiao Wang, Chenglin Liu, Haoxiang Sun, Hanwen Song
Summary: This paper presents a new decomposition mode for robot-world calibration, which decomposes the Ad(SE(3)) equation using Chasles' motion. A two-step method based on point set matching is proposed. The superiority of this method is verified through simulations and experiments.
MECHANISM AND MACHINE THEORY
(2024)
Article
Engineering, Mechanical
Yanlin Chen, Xianmin Zhang, Yanjiang Huang, Yanbin Wu, Jun Ota
Summary: This study establishes an error model for a 3-RRR+UR spherical parallel mechanism and analyzes the sensitivity of error parameters. A design structure is proposed to reduce input errors based on the analysis. Experimental results show that the multiloop circuit incremental method provides more accurate results.
MECHANISM AND MACHINE THEORY
(2024)
Article
Engineering, Mechanical
Vu Linh Nguyen, Chin-Hsing Kuo, Po Ting Lin
Summary: This paper presents a method for analyzing the performance of gravity-balanced serial robotic manipulators under dynamic loads and uses a three-degree-of-freedom planar serial manipulator as a case study. The significance of this method is demonstrated by evaluating the impact of dynamic loads on gravity-balanced performance and proposing a step-by-step design procedure to improve it.
MECHANISM AND MACHINE THEORY
(2024)
Article
Engineering, Mechanical
Shifeng Rong, Jiange Zhang, Xing Zhang, Keliang Li, Kaibin Rong, Zhenyu Zhou, Han Ding
Summary: This article proposes a data-driven dry cutting tool collaborative optimization model to improve the economic and environmental attributes of facehobbing hypoid gears. An innovative ease-off tooth contact analysis method is introduced to establish accurate relations between ease-off flank and loaded contact performance evaluations. The proposed model significantly improves sustainability in terms of economic and environmental assessments.
MECHANISM AND MACHINE THEORY
(2024)
Article
Engineering, Mechanical
Kemal Eren, Soley Ersoy, Ettore Pennestri
Summary: This research investigates the instantaneous kinematics of the terminal link of a planar two-link open chain using the complex-number technique and higher-order instantaneous invariants.
MECHANISM AND MACHINE THEORY
(2024)
Article
Engineering, Mechanical
Bo Han, Zhantu Yuan, Jiachuan Zhang, Yundou Xu, Jiantao Yao, Yongsheng Zhao
Summary: This paper proposes novel deployable mechanism units with self-limiting position function, and constructs ring truss deployable mechanisms. The degrees of freedom (DOF) of deployable units are analyzed and it is proved that the constructed ring truss deployable mechanisms have only one DOF. The dynamic model of the deployable mechanism unit with passive actuation is established and verified by simulation. The deployable mechanism units proposed in this paper have the advantages of good scalability and stability, and have broad application prospects.
MECHANISM AND MACHINE THEORY
(2024)
