Actuators

13 pages, 5417 KiB

Open AccessArticle

A Method for Improving Heat Dissipation and Avoiding Charging Effects for Cavity Silicon-on-Glass Structures

by Junduo Wang, Yuwei Hu, Lei Qian, Yameng Shan and Wenjiang Shen

Actuators 2023, 12(8), 337; https://doi.org/10.3390/act12080337 - 21 Aug 2023

Viewed by 981

Anode bonding is a widely used method for fabricating devices with suspended structures, and this approach is often combined with deep reactive-ion etching (DRIE) for releasing the device; however, the DRIE process with a glass substrate can potentially cause two critical issues: heat [...] Read more.

Anode bonding is a widely used method for fabricating devices with suspended structures, and this approach is often combined with deep reactive-ion etching (DRIE) for releasing the device; however, the DRIE process with a glass substrate can potentially cause two critical issues: heat accumulation on the suspended surface and charging effects resulting from the reflection of charged particles from the glass substrate. In particular, for torsional bars with narrow widths, the heat accumulated on the suspended surface may not dissipate efficiently, leading to photoresist burning and, subsequently, resulting in the fracture of the torsional bars; moreover, once etching is finished through the silicon diaphragm, the glass surface becomes charged, and incoming ions are reflected towards the back of the silicon, resulting in the etching of the back surface. To address these issues, we proposed a method of growing silicon oxide on the back of the device layer. By designing, simulating, and fabricating electrostatic torsional micromirrors with common cavity silicon-on-glass (SOG) structures, we successfully validated the feasibility of this approach. This approach ensures effective heat dissipation on the suspended surface, even when the structure is over-etched for an extended period, and enables the complete etching of torsional bars without adverse effects due to the overheating problem; additionally, the oxide layer can block ions from reaching the glass surface, thus avoiding the charging effect commonly observed in SOG structures during DRIE. Full article

(This article belongs to the Section Miniaturized and Micro Actuators)

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17 pages, 5110 KiB

Open AccessArticle

An Efficient and High-Precision Electromagnetic–Thermal Bidirectional Coupling Reduced-Order Solution Model for Permanent Magnet Synchronous Motors

by Yinquan Yu, Pan Zhao, HuiHwang Goh, Giuseppe Carbone, Shuangxia Niu, Junling Ding, Shengrong Shu and Zhao Zhao

Actuators 2023, 12(8), 336; https://doi.org/10.3390/act12080336 - 21 Aug 2023

Viewed by 1049

Abstract

The traditional electromagnetic–thermal bidirectional coupling model (EMTBCM) of permanent magnet synchronous motors (PMSMs) requires a long time to solve, and the temperature-induced torque change is not accounted for in the finite element (FE) numerical calculation of the EM field. This paper presents a [...] Read more.

The traditional electromagnetic–thermal bidirectional coupling model (EMTBCM) of permanent magnet synchronous motors (PMSMs) requires a long time to solve, and the temperature-induced torque change is not accounted for in the finite element (FE) numerical calculation of the EM field. This paper presents a precise and efficient EMTBC reduced-order solution model. The specific methods are as follows: First, a torque control technology based on the current injection method is proposed for determining the effect of temperature on the properties of EM materials and EM torque in an EM field, and the accuracy of the FE numerical calculation model is improved. Second, we use the improved EM field finite element numerical calculation model (FEMNCM) to analyze the correlation between the EM loss, the temperature, and the load, and we replace the FEMNCM with the EM field reduction model using the least-squares method. Then, we analyze the law of the PMSM’s internal temperature distribution. We choose the GA-BP algorithm with as few samples as possible and a high accuracy and stability to build the regression prediction model of the temperature field. We use this regression prediction model to replace the complex temperature field calculation. After analyzing the EMTBCM solution strategy, the original complex EMTBC numerical calculation model is substituted with iterations of the magnetic field reduction model and the temperature field regression prediction model. The FE numerical calculation is then used to validate the reduced-order model. The proposed model is validated through numerical simulations. The numerical results indicate that the proposed reduced-order EMTBC model in this paper is accurate and computationally efficient. Full article

(This article belongs to the Special Issue Power Electronics and Actuators)

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22 pages, 877 KiB

Open AccessArticle

Observer-Based Active Control Strategy for Networked Switched Systems against Two-Channel Asynchronous DoS Attacks

by Jiayuan Yin and Anyang Lu

Actuators 2023, 12(8), 335; https://doi.org/10.3390/act12080335 - 20 Aug 2023

Viewed by 1040

Abstract

This paper addresses the security issue of networked switched systems under two-channel asynchronous denial-of-service (DoS) attacks, where the measurement channel and the control channel are subject to DoS attacks independently. For the case of partial-state measurements, an observer-based active control strategy is proposed [...] Read more.

This paper addresses the security issue of networked switched systems under two-channel asynchronous denial-of-service (DoS) attacks, where the measurement channel and the control channel are subject to DoS attacks independently. For the case of partial-state measurements, an observer-based active control strategy is proposed to mitigate the negative impact on the control performance and stability of the system caused by the attacks. In this strategy, a novel mode-dependent finite-time observer is designed to estimate the system state rapidly and accurately, the predictor and the buffer are designed to ensure that the control signals transmitted to the actuator can be updated even when the control channel is blocked. Compared to the earlier results on the active control strategy that only consider the case of full-state measurements and assume that the DoS signals followed specific patterns, our work only limits the frequency and duration of the DoS signals, which is more general and challenging. Furthermore, the switching signal is designed to ensure the input-to-state stability (ISS) of the networked switched system with the active control strategy under two-channel asynchronous DoS attacks and asynchronous switching behaviors. Finally, the effectiveness and the merits of our work are validated through an example and a comparative experiment. Full article

(This article belongs to the Special Issue Sensor and Actuator Attacks of Cyber-Physical Systems)

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19 pages, 4749 KiB

Open AccessArticle

Research on Machine Vision-Based Control System for Cold Storage Warehouse Robots

by Zejiong Wei, Feng Tian, Zhehang Qiu, Zhechen Yang, Runyang Zhan and Jianming Zhan

Actuators 2023, 12(8), 334; https://doi.org/10.3390/act12080334 - 20 Aug 2023

Viewed by 1160

Abstract

In recent years, the global cold chain logistics market has grown rapidly, but the level of automation remains low. Compared to traditional logistics, automation in cold storage logistics requires a balance between safety and efficiency, and the current detection algorithms are poor at [...] Read more.

In recent years, the global cold chain logistics market has grown rapidly, but the level of automation remains low. Compared to traditional logistics, automation in cold storage logistics requires a balance between safety and efficiency, and the current detection algorithms are poor at meeting these requirements. Therefore, based on YOLOv5, this paper proposes a recognition and grasping system for cartons in cold storage warehouses. A human–machine interaction system is designed for the cold storage environment, enabling remote control and unmanned grasping. At the algorithm level, the CA attention mechanism is introduced to improve accuracy. The Ghost lightweight module replaces the CBS structure to enhance runtime speed. The Alpha-DIoU loss function is utilized to improve detection accuracy. With the comprehensive improvements, the modified algorithm in this study achieves a 0.711% increase in mAP and a 0.7% increase in FPS while maintaining accuracy. Experimental results demonstrate that the CA attention mechanism increases fidelity by 2.32%, the Ghost lightweight module reduces response time by 13.89%, and the Alpha-DIoU loss function enhances positioning accuracy by 7.14%. By incorporating all the improvements, the system exhibits a 2.16% reduction in response time, a 4.67% improvement in positioning accuracy, and a significant overall performance enhancement. Full article

(This article belongs to the Special Issue Design and Control of Actuators for Active Human−Machine Interaction)

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14 pages, 4124 KiB

Open AccessArticle

Research on Stability Control Technology of Hazardous Chemical Tank Vehicles Based on Electromagnetic Semi-Active Suspension

by Jianguo Dai, Youning Qin, Cheng Wang, Jianhui Zhu and Jingxuan Zhu

Actuators 2023, 12(8), 333; https://doi.org/10.3390/act12080333 - 17 Aug 2023

Cited by 1 | Viewed by 1039

Abstract

Liquid sloshing in the tank can seriously affect the stability of hazardous chemical tanker trucks during operation. To this end, this paper proposes a solution based on an electromagnetic semi-active suspension system to prevent chemical spills and ensure safe driving of hazardous chemical [...] Read more.

Liquid sloshing in the tank can seriously affect the stability of hazardous chemical tanker trucks during operation. To this end, this paper proposes a solution based on an electromagnetic semi-active suspension system to prevent chemical spills and ensure safe driving of hazardous chemical tank vehicles. A comprehensive investigation was conducted across four domains: theoretical research, simulation model establishment, co-simulation platform construction, and simulation data analysis. Three fuzzy controllers were used to suppress the vibration of the tank vehicles, and a simulation study of the stability control of the tank vehicles under electromagnetic semi-active suspension was carried out. The results show that the electromagnetic semi-active suspension can significantly reduce the vertical, pitch, and roll vibrations of the tank vehicles by 17.60%, 25.78%, and 27.86%, respectively. The research results of this paper are of great significance for improving the safety and stability of hazardous chemical tanker trucks. Full article

(This article belongs to the Special Issue Linear Motors and Direct-Drive Technology)

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20 pages, 721 KiB

Open AccessReview

Control Methodologies for Robotic Grippers: A Review

by Simone Cortinovis, Giuseppe Vitrani, Marco Maggiali and Rocco Antonio Romeo

Actuators 2023, 12(8), 332; https://doi.org/10.3390/act12080332 - 17 Aug 2023

Cited by 1 | Viewed by 2196

Abstract

As automation is spreading in all the industry domains, the presence of robots is becoming unavoidable inside factories, warehouses and manufacturing facilities. Although a great number of companies and research institutions have concentrated their efforts on developing new robotic systems and advanced algorithms, [...] Read more.

As automation is spreading in all the industry domains, the presence of robots is becoming unavoidable inside factories, warehouses and manufacturing facilities. Although a great number of companies and research institutions have concentrated their efforts on developing new robotic systems and advanced algorithms, much work is necessary to provide robotic grippers, especially industrial ones, with reliable, powerful control strategies. Therefore, this article aims at delivering an up-to-date point of view on the state of the art of robotic gripper control. The principal control methodologies employed so far, as well as a thorough selection of the existing contributions to the field, will be reported and discussed. Finally, the authors’ opinion about future directions will be expressed. Full article

(This article belongs to the Special Issue Advancement in the Design and Control of Robotic Grippers)

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20 pages, 3837 KiB

Open AccessArticle

Design and Research of Multimodal Fusion Feedback Device Based on Virtual Interactive System

by Zhen Zhang, Kenan Shi, Pan Ge, Taisheng Zhang, Manman Xu and Yu Chen

Actuators 2023, 12(8), 331; https://doi.org/10.3390/act12080331 - 16 Aug 2023

Viewed by 1148

Abstract

This paper proposes a kinesthetic–tactile fusion feedback system based on virtual interaction. Combining the results of human fingertip deformation characteristics analysis and an upper limb motion mechanism, a fingertip tactile feedback device and an arm kinesthetic feedback device are designed and analyzed for [...] Read more.

This paper proposes a kinesthetic–tactile fusion feedback system based on virtual interaction. Combining the results of human fingertip deformation characteristics analysis and an upper limb motion mechanism, a fingertip tactile feedback device and an arm kinesthetic feedback device are designed and analyzed for blind instructors. In order to verify the effectiveness of the method, virtual touch experiments are established through the mapping relationship between the master–slave and virtual end. The results showed that the average recognition rate of virtual objects is 79.58%, and the recognition speed is improved by 41.9% compared with the one without force feedback, indicating that the kinesthetic–tactile feedback device can provide more haptic perception information in virtual feedback and improve the recognition rate of haptic perception. Full article

(This article belongs to the Special Issue Actuators for Haptic Feedback Applications)

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18 pages, 5012 KiB

Open AccessArticle

Tracking and Vibration Control with a Parallel Structure Controller Based on a Flexible Ball Screw Drive System

by Muzhi Zhu, Dafei Bao, Mengxin Sun and Yong Liu

Actuators 2023, 12(8), 330; https://doi.org/10.3390/act12080330 - 16 Aug 2023

Viewed by 1011

Abstract

In this paper, we present a parallel structure controller for flexible ball screw drive systems with dynamic variations mainly caused by variations in table position and workpiece mass. The controller consists of two parts: a linear quadratic regulator (LQR) controller with the aim [...] Read more.

In this paper, we present a parallel structure controller for flexible ball screw drive systems with dynamic variations mainly caused by variations in table position and workpiece mass. The controller consists of two parts: a linear quadratic regulator (LQR) controller with the aim of tracking reference trajectories with high response and accuracy and an interpolated gain-scheduled controller used to restrain system vibration. To damp out the varied resonant modes, the controller is obtained by a set of μ-synthesis linear time-invariant (LTI) controllers interpolated via Youla parameterization. Comparison experiments are conducted to confirm the performance of the proposed controller with a ball screw drive experimental setup. We demonstrate that the parallel structure controller achieves high performance in tracking, vibration suppression and disturbance rejection. Full article

(This article belongs to the Section Control Systems)

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26 pages, 1403 KiB

Open AccessArticle

Design and Optimization of a Novel Electronic Mechanical Brake Actuator Based on Cam

by Zhoudong Yan, Xinbo Chen, Min Yan and Peng Hang

Actuators 2023, 12(8), 329; https://doi.org/10.3390/act12080329 - 16 Aug 2023

Viewed by 1222

Abstract

The electronic mechanical brake (EMB) is considered an ideal actuator for brake-by-wire systems. We applied the negative radius roller cam mechanism as the clamping mechanism of the EMB, solving the problem of large size, poor load-bearing capacity, and the inefficiency of the existing [...] Read more.

The electronic mechanical brake (EMB) is considered an ideal actuator for brake-by-wire systems. We applied the negative radius roller cam mechanism as the clamping mechanism of the EMB, solving the problem of large size, poor load-bearing capacity, and the inefficiency of the existing EMBs. When designing a cam as a clamping transmission mechanism, it is necessary to take the pressure angle, contact stress, motion law, etc., as goals and constraints. Existing design methods cannot easily solve this problem. Therefore, we propose a new analysis method from the cam profile and combine it with an improved particle swarm optimization (PSO) algorithm to design the cam profiles. This method can handle various complex goals and constraints of the EMB and obtain the required negative radius roller cam profile. Finally, the logical consistency of the profile-based analysis method was verified, and the EMB design objectives and accuracy were compared using ADAMS. Under the same conditions, the result showed that the optimized cam mechanism requires only 40.52% motor power and only 65.65% clearance elimination time compared to the EMB with the lead screw mechanism. Full article

(This article belongs to the Special Issue Actuators and Control of Intelligent Electric Vehicles)

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22 pages, 8932 KiB

Open AccessArticle

Hybrid Solenoids Based on Magnetic Shape Memory Alloys

by Manuel Mauch, Marco Hutter and Bernd Gundelsweiler

Actuators 2023, 12(8), 328; https://doi.org/10.3390/act12080328 - 15 Aug 2023

Cited by 1 | Viewed by 1295

Abstract

The mobility of today and tomorrow is characterized by technological change and new challenges in drive concepts such as electric or hydrogen vehicles. Abolishing conventional combustion engines creates even more need for switching or valve technology in mobility systems. For switching and controlling [...] Read more.

The mobility of today and tomorrow is characterized by technological change and new challenges in drive concepts such as electric or hydrogen vehicles. Abolishing conventional combustion engines creates even more need for switching or valve technology in mobility systems. For switching and controlling purposes, solenoids are used in large numbers and in a wide variety of applications, thus making a significant contribution to the overall success of the energy transition, and not only in the automotive sector. Despite their long existence, continued research is being carried out on solenoids involving new materials and actuator concepts. Great interest is focused on providing an adjustable force–displacement characteristic while simultaneously reducing the noise during switching. At IKFF, research is being conducted on hybrid electromagnets in the border area of switching and holding solenoids. This paper aims to present the major advantages of this hybrid drive concept based on an electromagnetic FEA simulation study of two drive concepts and specially developed and characterized prototypes with magnetic shape memory (MSM) alloys. The concepts differ in the spatial orientation of the MSM sticks to generate an active stroke of the plunger, which contributes to a beneficial force–displacement characteristic and lower power consumption while minimizing switching noise. Full article

(This article belongs to the Special Issue Innovative Actuators Based on Shape Memory Alloys)

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17 pages, 8061 KiB

Open AccessArticle

Improved Rotor Flux-Based SMO and RBF-PID Control Strategy for PMSM

by Weiyang Wang, Yongqing Liu, Huipeng Chen, Jian Gao, Shaopeng Zhu and Rougang Zhou

Actuators 2023, 12(8), 327; https://doi.org/10.3390/act12080327 - 15 Aug 2023

Viewed by 1058

Abstract

This paper proposes a control strategy that combines an improved flux-based sliding mode observer with a Radial Basis Function Proportional-Integral-Derivative (RBF-PID) controller for the control of Permanent Magnet Synchronous Motors (PMSM). The strategy aims to address the issues of electrical angle estimation errors [...] Read more.

This paper proposes a control strategy that combines an improved flux-based sliding mode observer with a Radial Basis Function Proportional-Integral-Derivative (RBF-PID) controller for the control of Permanent Magnet Synchronous Motors (PMSM). The strategy aims to address the issues of electrical angle estimation errors and torque fluctuations in traditional sliding mode observer control. The improved sliding mode observer utilizes the flux model of the PMSM to enhance the accuracy of electrical angle estimation, thereby reducing the estimation errors and improving the control of the current loop and speed. The RBF-PID controller ensures system stability while achieving faster response and reduced torque fluctuations. Simulation and experimental results demonstrate that compared to traditional PI control and sliding mode observer control methods, the proposed strategy improves the performance of electrical angle estimation by 7.05% and reduces overshoot in the q-axis current by 28.6%, exhibiting better control performance and smaller errors. Full article

(This article belongs to the Section High Torque/Power Density Actuators)

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24 pages, 6052 KiB

Open AccessArticle

A Self-Adaptive Double Q-Backstepping Trajectory Tracking Control Approach Based on Reinforcement Learning for Mobile Robots

by Naifeng He, Zhong Yang, Xiaoliang Fan, Jiying Wu, Yaoyu Sui and Qiuyan Zhang

Actuators 2023, 12(8), 326; https://doi.org/10.3390/act12080326 - 14 Aug 2023

Cited by 2 | Viewed by 1239

Abstract

When a mobile robot inspects tasks with complex requirements indoors, the traditional backstepping method cannot guarantee the accuracy of the trajectory, leading to problems such as the instrument not being inside the image and focus failure when the robot grabs the image with [...] Read more.

When a mobile robot inspects tasks with complex requirements indoors, the traditional backstepping method cannot guarantee the accuracy of the trajectory, leading to problems such as the instrument not being inside the image and focus failure when the robot grabs the image with high zoom. In order to solve this problem, this paper proposes an adaptive backstepping method based on double Q-learning for tracking and controlling the trajectory of mobile robots. We design the incremental model-free algorithm of Double-Q learning, which can quickly learn to rectify the trajectory tracking controller gain online. For the controller gain rectification problem in non-uniform state space exploration, we propose an incremental active learning exploration algorithm that incorporates memory playback as well as experience playback mechanisms to achieve online fast learning and controller gain rectification for agents. To verify the feasibility of the algorithm, we perform algorithm verification on different types of trajectories in Gazebo and physical platforms. The results show that the adaptive trajectory tracking control algorithm can be used to rectify the mobile robot trajectory tracking controller’s gain. Compared with the Backstepping-Fractional-Older PID controller and Fuzzy-Backstepping controller, Double Q-backstepping has better robustness, generalization, real-time, and stronger anti-disturbance capability. Full article

(This article belongs to the Section Actuators for Robotics)

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17 pages, 3386 KiB

Open AccessArticle

A Tangent Release Manipulation Controlled by a Dual-Arm Space Robot

by Xiaoyi Wang and Jayantha Katupitiya

Actuators 2023, 12(8), 325; https://doi.org/10.3390/act12080325 - 14 Aug 2023

Viewed by 1105

Abstract

As people further develop space with advanced technology, space robots have played a significant role in on-orbit servicing missions. Space robots can carry out more risky and complicated missions with less cost than astronauts. Dual-arm space robots can perform complex on-orbit space missions [...] Read more.

As people further develop space with advanced technology, space robots have played a significant role in on-orbit servicing missions. Space robots can carry out more risky and complicated missions with less cost than astronauts. Dual-arm space robots can perform complex on-orbit space missions more effectively than single-arm space robots. Since the coupled dynamics between the free-floating base and the arms exist in space robots, accurate coordinate control of the base and the arms is essential. Spacecraft release missions have been proposed to berth/deberth a spacecraft to a space station. Based on the existing release missions, a tangent release strategy is introduced in this paper, which can release a space object in the tangent direction of the final link of a space manipulator. This strategy can control a dual-arm space robot to deploy cargo/spacecraft in variable directions in 3D space without thrusters and the associated fuel consumption. For instance, this tangent release operation can transport cargo or modules of large-scale spacecraft needing on-orbit assembly. Considering model uncertainties, robust controllers again model uncertainties that are used to control the dual-arm space robot with high accuracy. Hence, a robust sliding mode controller (SMC) is utilized to accurately control the space robot to carry out the proposed tangent release strategy. For comparison, we select a conventional computed torque control (CTC) implemented by a PD-type controller. In the simulations, the SMC performs better in tracking accuracy and robustness against the model uncertainties than the PD controller. Numerical simulations indicate the feasibility and effectiveness of the tangent release manipulation of a space object by a dual-arm space robot. Full article

(This article belongs to the Special Issue Advanced Spacecraft Structural Dynamics and Actuation Control)

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24 pages, 4853 KiB

Open AccessArticle

Error Analysis of a New Five-Degree-of-Freedom Hybrid Robot

by Hongjun San, Lin Ding, Haobin Zhang and Xingmei Wu

Actuators 2023, 12(8), 324; https://doi.org/10.3390/act12080324 - 13 Aug 2023

Cited by 1 | Viewed by 1075

Abstract

The error analysis of the robot has a very practical significance for improving its accuracy. Therefore, this paper conducts an error analysis for a new five-degree-of-freedom hybrid robot designed to conduct responsible surface machining. Initially, the error sources of the hybrid robot were [...] Read more.

The error analysis of the robot has a very practical significance for improving its accuracy. Therefore, this paper conducts an error analysis for a new five-degree-of-freedom hybrid robot designed to conduct responsible surface machining. Initially, the error sources of the hybrid robot were sorted out to determine the number of error sources. Then, the error mapping model of the hybrid robot is established by the closed-loop vector method and the first-order perturbation method. Based on the mapping property of the 6th-order velocity Jacobi matrix, the compensable and non-compensable error sources affecting the posture error at the end of the hybrid robot are separated. Finally, the error analysis of the separated error sources is carried out to study the effect of single error sources and multiple error sources coupled with the posture error at the end of the robot. The results show that among the individual error sources, the dynamic and fixed platform hinge position error has the most significant effect on the end of the robot; among the integrated posture errors after coupling multiple error sources, the position of the dynamic and fixed platform hinge position error and the translational joint initial position dominate; the analysis of the different trajectories also yields that the error introduced by each error source increases gradually with the increase of the end trajectory. When designing this hybrid robot, attention should be paid to the manufacturing and installation accuracy of the dynamic and fixed platform hinge point positions and the translational joint initial position. Full article

(This article belongs to the Section Actuators for Robotics)

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29 pages, 7081 KiB

Open AccessReview

Recent Advancements in Augmented Reality for Robotic Applications: A Survey

by Junling Fu, Alberto Rota, Shufei Li, Jianzhuang Zhao, Qingsheng Liu, Elisa Iovene, Giancarlo Ferrigno and Elena De Momi

Actuators 2023, 12(8), 323; https://doi.org/10.3390/act12080323 - 13 Aug 2023

Cited by 7 | Viewed by 4391

Abstract

Robots are expanding from industrial applications to daily life, in areas such as medical robotics, rehabilitative robotics, social robotics, and mobile/aerial robotics systems. In recent years, augmented reality (AR) has been integrated into many robotic applications, including medical, industrial, human–robot interactions, and collaboration [...] Read more.

Robots are expanding from industrial applications to daily life, in areas such as medical robotics, rehabilitative robotics, social robotics, and mobile/aerial robotics systems. In recent years, augmented reality (AR) has been integrated into many robotic applications, including medical, industrial, human–robot interactions, and collaboration scenarios. In this work, AR for both medical and industrial robot applications is reviewed and summarized. For medical robot applications, we investigated the integration of AR in (1) preoperative and surgical task planning; (2) image-guided robotic surgery; (3) surgical training and simulation; and (4) telesurgery. AR for industrial scenarios is reviewed in (1) human–robot interactions and collaborations; (2) path planning and task allocation; (3) training and simulation; and (4) teleoperation control/assistance. In addition, the limitations and challenges are discussed. Overall, this article serves as a valuable resource for working in the field of AR and robotic research, offering insights into the recent state of the art and prospects for improvement. Full article

(This article belongs to the Special Issue Motion Planning and Control of Robot Systems)

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25 pages, 20819 KiB

Open AccessArticle

Comparison of Separation Control Mechanisms for Synthetic Jet and Plasma Actuators

by Yoshiaki Abe, Taku Nonomura, Makoto Sato, Hikaru Aono and Kozo Fujii

Actuators 2023, 12(8), 322; https://doi.org/10.3390/act12080322 - 11 Aug 2023

Cited by 1 | Viewed by 1237

Abstract

This study numerically investigated the mechanisms of separation control using a synthetic jet (SJ) and plasma actuator (PA) around an NACA0015 airfoil at the chord Reynolds number of 63,000. Both SJ and PA were installed on the leading edge with the same order [...] Read more.

This study numerically investigated the mechanisms of separation control using a synthetic jet (SJ) and plasma actuator (PA) around an NACA0015 airfoil at the chord Reynolds number of 63,000. Both SJ and PA were installed on the leading edge with the same order of input momentum (

C_{μ} = O (10^{- 3}

–

10^{- 5})

) and the same actuation frequencies in

F^{+} = 1.0

–30. The momentum coefficient

C_{μ}

is defined as the normalized momentum introduced from the SJ or the PA, and

F^{+}

stands for the actuation frequency normalized by the chord length and uniform velocity. A number of large-eddy simulations (LES) were conducted for the SJ and the PA, and the mechanisms were clarified in terms of the exchange of chordwise momentum with Reynolds shear stress and coherent vortex structures. First, four main differences in the induced flows of the SJ and the PA were clarified as follows: (A) wall-tangential velocity; (B) three-dimensional flow structures; (C) spatial locality; and (D) temporal fluctuation. Then, a common feature of flow control by the SJ and the PA was revealed: a lift-to-drag ratio was found to be better recovered in

F^{+} = 6.0

–20 than in other frequencies. Although there were differences in the induced flows, the phase decomposition of the flow fields identified common mechanisms that the turbulent component of the Reynolds shear stress mainly contributes to the exchange of the chordwise (streamwise) momentum; and the turbulent vortices are convected over the airfoil surface by the coherent spanwise vortices in the frequency of

F^{+}

. Full article

(This article belongs to the Special Issue Dielectric Barrier Discharge Plasma Actuator for Active Flow Control)

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16 pages, 3756 KiB

Open AccessArticle

A Bionic Control Method for Human–Exoskeleton Coupling Based on CPG Model

by Tianyi Sun, Shujun Zhang, Ruiqi Li and Yao Yan

Actuators 2023, 12(8), 321; https://doi.org/10.3390/act12080321 - 09 Aug 2023

Viewed by 1142

Abstract

Exoskeleton robots are functioning in contexts with more complicated motion control needs as a result of the technology and applications for these robots rapidly developing. This calls for novel control techniques to accommodate their employment in a range of real-world settings. This paper [...] Read more.

Exoskeleton robots are functioning in contexts with more complicated motion control needs as a result of the technology and applications for these robots rapidly developing. This calls for novel control techniques to accommodate their employment in a range of real-world settings. This paper proposes a bionic control method for a human–exoskeleton coupling dynamic model based on the CPG model, utilizing a model on the dynamics of the human–exoskeleton interaction. The CPG network is established as an oscillator by two neurons inhibiting one another, which approximates the torques simulated in the inverse dynamic analysis as the input to the exoskeleton robot. The findings of the simulation assessment suggest that the bionic control strategy may improve the robot’s ability to move quickly and steadily, as well as better adapt to challenging environments. Full article

(This article belongs to the Special Issue Design and Control of Actuators for Active Human−Machine Interaction)

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17 pages, 3563 KiB

Open AccessArticle

Research on Identifying Robot Collision Points in Human–Robot Collaboration Based on Force Method Principle Solving

by Zhijun Wang, Bocheng Zhu, Yue Yang and Zhanxian Li

Actuators 2023, 12(8), 320; https://doi.org/10.3390/act12080320 - 09 Aug 2023

Viewed by 953

Abstract

After years of more rigid and conventional production processes, the traditional manufacturing industry has been moving toward flexible manufacturing and intelligent manufacturing in recent years. After more than half a century of development, robotics has penetrated into all aspects of human production and [...] Read more.

After years of more rigid and conventional production processes, the traditional manufacturing industry has been moving toward flexible manufacturing and intelligent manufacturing in recent years. After more than half a century of development, robotics has penetrated into all aspects of human production and life, bringing significant changes to the development of human society. At the same time, the key technology of human–machine cooperative operation has become a research hotspot, and how to realize a human–machine integrated safety system has attracted attention. Human–machine integration means that humans and robots can work in the same natural space, coordinating closely and interacting naturally. To realize real human–robot integration under human–robot cooperative operation, the good judgment of intentional interaction and accidental collision and the detection of collision joints and collision points when accidental collision occurs are the key points. In this paper, we propose a method to identify the collision joints by detecting real-time current changes in each joint of the robot and solve the collision point location information of the collision joints through the principle of virtual displacement and the principle of force method using the force sensor data installed at the base of the robot as the known condition. The results show that the proposed method of identifying the collision joints using changes in joint current and then establishing a collision detection algorithm to solve the collision point location is correct and reliable. Full article

(This article belongs to the Special Issue Design and Control of Actuators for Active Human−Machine Interaction)

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23 pages, 1168 KiB

Open AccessArticle

A Non-Arrhenius Model for Mechanism Consistency Checking in Accelerated Degradation Tests

by Jiaxin You, Rao Fu, Huimin Liang and Yigang Lin

Actuators 2023, 12(8), 319; https://doi.org/10.3390/act12080319 - 08 Aug 2023

Viewed by 991

Abstract

Degradation models are central to the lifetime prediction of electromagnetic relays. Coefficients of degradation models under accelerated degradation test (ADTs) can be obtained experimentally, and it is customary to map these coefficients back to those describing the actual degradation by the so-called Arrhenius [...] Read more.

Degradation models are central to the lifetime prediction of electromagnetic relays. Coefficients of degradation models under accelerated degradation test (ADTs) can be obtained experimentally, and it is customary to map these coefficients back to those describing the actual degradation by the so-called Arrhenius model. However, for some components, such as springs in electromagnetic relays, the Arrhenius model is only appropriate over a certain ADT temperature range, which implies inaccurate mapping outside that range. On this point, an error function model (EFM) is proposed to overcome the shortcomings of the Arrhenius model. EFM is derived from the average vibration energy of the crystal, which is further related to temperature alongside some constants. The empirical part of the paper compares the proposed EFM to the Arrhenius model for the ADT of 28-V–2-A electromagnetic relays. The results show that EFM is superior in describing the temperature characteristics of coefficients in the degradation model. Through mechanism consistency checking, EFM is also shown to be a better option than the Arrhenius model. Moving beyond the case of electromagnetic relays, EFM is thought to have better applicability in the degradation models of capacitors and rubbers. Full article

(This article belongs to the Special Issue Advanced Technologies on the Control Method of Electromagnetic Actuator)

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12 pages, 8455 KiB

Open AccessArticle

Energy Efficiency and Performance Evaluation of an Exterior-Rotor Brushless DC Motor and Drive System across the Full Operating Range

by Tsung-Han Hsieh, Seong Ho Yeon and Hugh Herr

Actuators 2023, 12(8), 318; https://doi.org/10.3390/act12080318 - 06 Aug 2023

Cited by 1 | Viewed by 1387

Abstract

In recent years, exterior-rotor brushless DC motors have become increasingly popular in robotics applications due to their compact shape and high torque density. However, these motors were originally used for continuous operation in drones. For applications such as exoskeletons, prostheses, or legged robots, [...] Read more.

In recent years, exterior-rotor brushless DC motors have become increasingly popular in robotics applications due to their compact shape and high torque density. However, these motors were originally used for continuous operation in drones. For applications such as exoskeletons, prostheses, or legged robots, short bursts of high power are often required. Unfortunately, vendors do not typically provide data on the motors’ performance under these conditions. This paper presents experimental data on the torque–speed relationship, efficiency, and thermal responses of one of the most widely used outrunner-type brushless motors across its full operating range, including high-power short-duration operation. The results of this study can inform the selection and design of actuators for a range of robotics applications, particularly those that require high power output for brief periods of time. Full article

(This article belongs to the Section Actuators for Robotics)

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16 pages, 13419 KiB

Open AccessArticle

Mining Electric Shovel Working Device Configuration Synthesis and Performance Analysis

by Chenhao Guo, Juan Wu, Yinnan Feng, Xin Wang and Yuliang Wang

Actuators 2023, 12(8), 317; https://doi.org/10.3390/act12080317 - 05 Aug 2023

Cited by 1 | Viewed by 1372

Abstract

Mining electric shovels (MES) are one of the key pieces of equipment for mining, and their comprehensive performance plays an important role in mining efficiency. Based on the screw theory, this paper proposes a comprehensive configuration method for an MES working device and [...] Read more.

Mining electric shovels (MES) are one of the key pieces of equipment for mining, and their comprehensive performance plays an important role in mining efficiency. Based on the screw theory, this paper proposes a comprehensive configuration method for an MES working device and selects a new mining electric shovel working device with a larger excavation range, taking the working device as an example for dimensional optimization and simulation analysis. Firstly, based on the closed-loop vector equation, the position inverse solution of the mechanism is analyzed, and the correctness of the position equation is verified by the simulation and by numerical solutions. Then, the constraints of the mechanism are analyzed, and the numerical method and the position equation are combined to solve for the workspace of the mechanism. The dimensional parameters of the mechanism are optimized by genetic algorithms. The workspace of the optimized working device is increased by 13.4789%. Finally, the mining results of the two MES, the working devices, are simulated and verified by experiment. It is shown that the experimental results are basically consistent with the simulation results. The excavation quality difference of the two working devices are 2.02% and 2.20%, which verifies the correctness of the kinematics equation of the working device and the feasibility of the new working device. Full article

(This article belongs to the Special Issue Innovative and Intelligent Actuation for Heavy-Duty Applications)

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18 pages, 7147 KiB

Open AccessArticle

Closed-Loop FES Control of a Hybrid Exoskeleton during Sit-to-Stand Exercises: Concept and First Evaluation

by Chenglin Lyu, Pedro Truppel Morim, Bernhard Penzlin, Felix Röhren, Lukas Bergmann, Philip von Platen, Cornelius Bollheimer, Steffen Leonhardt and Chuong Ngo

Actuators 2023, 12(8), 316; https://doi.org/10.3390/act12080316 - 05 Aug 2023

Viewed by 1580

Abstract

Rehabilitation of paralysis caused by a stroke or a spinal cord injury remains a complex and time-consuming task. This work proposes a hybrid exoskeleton approach combining a traditional exoskeleton and functional electrical stimulation (FES) as a promising method in rehabilitation. However, hybrid exoskeletons [...] Read more.

Rehabilitation of paralysis caused by a stroke or a spinal cord injury remains a complex and time-consuming task. This work proposes a hybrid exoskeleton approach combining a traditional exoskeleton and functional electrical stimulation (FES) as a promising method in rehabilitation. However, hybrid exoskeletons with a closed-loop FES control strategy are functionally challenging to achieve and have not been reported often. Therefore, this study aimed to investigate a powered lower-limb exoskeleton with a closed-loop FES control for Sit-to-Stand (STS) movements. A body motion capture system was applied to record precise hip and knee trajectories of references for establishing the human model. A closed-loop control strategy with allocation factors is proposed featuring a two-layer cascaded proportional–integral–derivative (PID) controller for both FES and exoskeleton control. Experiments were performed on two participants to examine the feasibility of the hybrid exoskeleton and the closed-loop FES control. Both open- and closed-loop FES control showed the desired performance with a relatively low root-mean-squared error (max 1.3

^{\circ}

in open-loop and max 4.1

^{\circ}

in closed-loop) in hip and knee trajectories. Notably, the closed-loop FES control strategy can achieve the same performance with nearly 60% of the electrical power input compared to the open-loop control, which reduced muscle fatigue and improved robustness during the training. This study provides novel insights into body motion capture application and proposes a closed-loop FES control for hybrid exoskeletons. Full article

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24 pages, 6141 KiB

Open AccessArticle

Optimal Design and Control Performance Evaluation of a Magnetorheological Fluid Brake Featuring a T-Shape Grooved Disc

by Pacifique Turabimana and Jung Woo Sohn

Actuators 2023, 12(8), 315; https://doi.org/10.3390/act12080315 - 05 Aug 2023

Cited by 1 | Viewed by 1853

Abstract

Magnetorheological fluid brakes are a promising technology for developing high-performance drive-by-wire braking systems due to their controllability and adaptability. This research aims to design an optimal magnetorheological fluid brake for motorcycles and their performance. The proposed model utilizes mathematical modeling and finite element [...] Read more.

Magnetorheological fluid brakes are a promising technology for developing high-performance drive-by-wire braking systems due to their controllability and adaptability. This research aims to design an optimal magnetorheological fluid brake for motorcycles and their performance. The proposed model utilizes mathematical modeling and finite element analysis using commercial software. Furthermore, the optimization of this MR brake is determined through multi-objective optimization with a genetic algorithm that maximizes braking torque while simultaneously minimizing weight and the cruising temperature. The novelty lies in the geometric shape of the disc, bobbin, and MR fluid channels, which results in a light MR brake weighing 6.1 kg, an operating temperature of 89.5 °C, and a power consumption of 51 W with an output braking torque of 303.9 Nm. Additionally, the control performance is evaluated using an extended Kalman filter controller. This controller effectively regulates braking torque, speed, and slip rate of both the rear and front wheels based on road characteristics and motorcycle dynamics. This study’s findings show that the front wheel necessitates higher braking torque compared to the rear wheel. Moreover, the slip rate is higher on the rear wheel than on the front wheel, but the front wheel stops earlier than the rear wheel. Full article

(This article belongs to the Special Issue Smart-Materials-Based Actuators—a Special Issue in Honor of Prof. Dr. Jaehwan Kim)

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15 pages, 17139 KiB

Open AccessArticle

Design and Experimental Study of Cavity Structure of Pneumatic Soft Actuator

by Yang Yu and Tao Fu

Actuators 2023, 12(8), 314; https://doi.org/10.3390/act12080314 - 04 Aug 2023

Cited by 1 | Viewed by 1317

Abstract

In order to study the influence of the cavity inclination angle bending performance of pneumatic soft actuators, two kinds of soft actuators were designed, one with a five-degree-angle cavity structure, and the other with a hybrid variable-degree-angle cavity structure. The bending performance of [...] Read more.

In order to study the influence of the cavity inclination angle bending performance of pneumatic soft actuators, two kinds of soft actuators were designed, one with a five-degree-angle cavity structure, and the other with a hybrid variable-degree-angle cavity structure. The bending performance of zero-degree-angle, five-degree-angle, and hybrid variable-degree-angle soft actuators was investigated by experimental methods and the ABAQUS finite element simulation method. The results show that, under seven different pressure loads, the mean absolute error between the experimental results and the numerical simulation results for the zero-degree-angle soft actuator was 0.926, for the five-degree-angle soft actuator it was 1.472, and for the hybrid variable-degree-angle soft actuator it was 1.22. When the pressure load changed from 4 kPa to 16 kPa, the five-degree-angle soft actuator had the largest range-of-angle variation, with the bending angle increasing 193.31%, from 26.92 degrees to 78.97 degrees. In the same longitudinal displacement, the five-degree-angle soft actuator had the largest lateral displacement variation, and the bending effect was the best compared with the zero-degree-angle soft actuator and the hybrid variable-degree-angle soft actuator. According to the experimental and numerical simulation results, with the same structural parameter design, the cavity tilt angle increases, which can increase the bending angle variation range and improve the bending performance of soft actuators. Full article

(This article belongs to the Special Issue Soft Actuators for Soft Robotics)

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16 pages, 11272 KiB

Open AccessArticle

A Novel Strain Wave Gear Reducer with Double Flexsplines

by Zilong Ling, Lei Zhao, Dong Xiao, Yi Zhou, Cui Ma, Kai He and Guanyi Liu

Actuators 2023, 12(8), 313; https://doi.org/10.3390/act12080313 - 01 Aug 2023

Viewed by 1890

Abstract

Strain wave gear reducers, also known as harmonic drives, are widely used in industrial robots and collaborative robots. The zero-backlash feature is very important for these applications. However, this places extremely high demands on the machining accuracy of the strain wave gear reducer. [...] Read more.

Strain wave gear reducers, also known as harmonic drives, are widely used in industrial robots and collaborative robots. The zero-backlash feature is very important for these applications. However, this places extremely high demands on the machining accuracy of the strain wave gear reducer. Excessive manufacturing errors will lead to excessive backlash, affecting transmission accuracy or making installation difficult, and the flexible spline (or flexspline) is prone to wear, resulting in reduced accuracy with use. This study proposes a novel strain wave gear reducer with a double flexspline structure. The original “circular spline” which was rigid will be redesigned to be slightly flexible and deformable with an additional deformation adjustment structure, which reduces the requirements for machining accuracy, and realizes the same zero-backlash characteristic of traditional structure. The experimental results show that the new strain wave gear reducer has extremely low lost motion, hysteresis loss, and high torsional rigidity. The new strain wave gear reducer provides a more economical way to realize the zero-backlash reducer and helps to solve the problem of the accuracy decline of the strain wave gear reducer due to the wear of the flexspline. Full article

(This article belongs to the Section Actuators for Robotics)

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29 pages, 10949 KiB

Open AccessArticle

HBS-1.2: Lightweight Socially Assistive Robot with 6-Ply Twisted Coiled Polymer Muscle-Actuated Hand

by Abhishek Pratap Singh, Darshan Palani, Onan Ahmed, Pawandeep Singh Matharu, Tristan Linn, Trung Nguyen and Yonas Tadesse

Actuators 2023, 12(8), 312; https://doi.org/10.3390/act12080312 - 01 Aug 2023

Cited by 2 | Viewed by 2050

Abstract

In this paper, a new socially assistive robot (SARs) called HBS-1.2 is presented, which uses 6-ply twisted and coiled polymer (TCP) artificial muscles in its hand to perform physical tasks. The utilization of 6-ply TCP artificial muscles in a humanoid robot hand is [...] Read more.

In this paper, a new socially assistive robot (SARs) called HBS-1.2 is presented, which uses 6-ply twisted and coiled polymer (TCP) artificial muscles in its hand to perform physical tasks. The utilization of 6-ply TCP artificial muscles in a humanoid robot hand is a pioneering advancement, offering cost effective, lightweight, and compact solution for SARs. The robot is designed to provide safer human–robot interaction (HRI) while performing physical tasks. The paper explains the procedures for fabrication and testing of the 6-ply TCP artificial muscles, along with improving the actuation response by using a Proportional-Integral-Derivative (PID) control method. Notably, the robot successfully performed a vision-based pick and place experiment, showing its potential for use in homecare and other settings to assist patients who suffer from neurological diseases like Alzheimer’s disease. The study also found an optimal light intensity range between 34 to 108 lumens/m², which ensures minimal variation in calculated distance with 95% confidence intervals for robust performance from the vison system. The findings of this study have important implications for the development of affordable and accessible robotic systems to support elderly patients with dementia, and future research should focus on further improving the use of TCP actuators in robotics. Full article

(This article belongs to the Special Issue Actuators in Assistive and Rehabilitation Robotics)

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15 pages, 7101 KiB

Open AccessArticle

Design and Optimization of Multifunctional Human Motion Rehabilitation Training Robot EEGO

by Kun Liu, Shuo Ji, Yong Liu, Chi Gao, Jun Fu, Lei Dai and Shizhong Zhang

Actuators 2023, 12(8), 311; https://doi.org/10.3390/act12080311 - 28 Jul 2023

Cited by 1 | Viewed by 1151

Abstract

A multifunctional human motion rehabilitation training robot named EEGO (electric easy go) that could achieve four functions through structural transformation was designed. The four functions achieved by four working modes: the Supporting Posture Mode (SM), the Grasping Posture Mode (GM), the Riding Posture [...] Read more.

A multifunctional human motion rehabilitation training robot named EEGO (electric easy go) that could achieve four functions through structural transformation was designed. The four functions achieved by four working modes: the Supporting Posture Mode (SM), the Grasping Posture Mode (GM), the Riding Posture Mode (RM), and the Pet Mode (PM), which are suitable for patients in the middle and late stages of rehabilitation. The size of the equipment under different functions is determined by the height of different postures of the human. During the design process, the equipment was lightweight using size optimization methods, resulting in a 47.3% reduction in mass compared to the original design. Based on the Zero Moment Point (ZMP) stability principle, the stability mechanism of the robot was verified under the three different functions. According to the wanted function of the equipment, the control system of the equipment was designed. Finally, a prototype was prepared based on the analysis and design results for experimental verification, which can effectively assist patients in motion rehabilitation training such as gait, walking, and other movements. Full article

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19 pages, 6613 KiB

Open AccessArticle

Force-Fighting Phenomena and Disturbance Rejection in Aircraft Dual-Redundant Electro-Mechanical Actuation Systems

by Young Tak Han, Sang-Duck Im and Bongsu Hahn

Actuators 2023, 12(8), 310; https://doi.org/10.3390/act12080310 - 28 Jul 2023

Cited by 1 | Viewed by 1081

Abstract

This paper presents a robust control system that addresses two key challenges in redundant actuators using Permanent Magnet Synchronous Motors (PMSM) for an aircraft nose wheel steering system: the elimination of force-fighting phenomena and the ability to respond effectively to unexpected disturbances. In [...] Read more.

This paper presents a robust control system that addresses two key challenges in redundant actuators using Permanent Magnet Synchronous Motors (PMSM) for an aircraft nose wheel steering system: the elimination of force-fighting phenomena and the ability to respond effectively to unexpected disturbances. In detail, a control method was devised to enhance the mitigation of force-fighting phenomena and disturbances by accurately observing and compensating for the torque-induced load applied to the PMSM. This was achieved through the utilization of a Q-filter-based Disturbance Observer (DOB). The proposed control approach was implemented and evaluated on a redundant system consisting of the PMSM and the nose wheel steering system. The performance of the proposed method was verified through extensive simulation studies. The simulation results confirmed the effectiveness and reliability of the method in accurately observing and responding to the force-fighting phenomenon that occurs in the redundant driving device. By subjecting the system to various scenarios and disturbances, the simulation provided a comprehensive evaluation of the proposed method’s ability to handle force-fighting phenomena. The results demonstrated that the method successfully observed and responded to the force-fighting phenomenon, thereby mitigating its adverse effects on the system’s performance. Therefore, these outcomes serve as empirical evidence supporting the validity and efficiency of the proposed method in addressing the force-fighting phenomenon encountered in the redundant driving device. These findings substantiate the effectiveness of the proposed approach and its potential for practical implementation in real-world systems. Full article

(This article belongs to the Special Issue Electromagnetic Actuators)

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15 pages, 14382 KiB

Open AccessArticle

Design, Control, and Assessment of a Synergy-Based Exosuit for Patients with Gait-Associated Pathologies

by Ashwin Jayakumar, Javier Bermejo-García, Daniel Rodríguez Jorge, Rafael Agujetas, Francisco Romero-Sánchez and Francisco J. Alonso-Sánchez

Actuators 2023, 12(8), 309; https://doi.org/10.3390/act12080309 - 28 Jul 2023

Viewed by 1182

Abstract

With ever-rising population comes a corresponding rise in people with mobility issues who have difficulty handling tasks in their daily lives. Such persons could benefit significantly from an active movement assistance device. This paper presents the design of a lower-limb exosuit designed to [...] Read more.

With ever-rising population comes a corresponding rise in people with mobility issues who have difficulty handling tasks in their daily lives. Such persons could benefit significantly from an active movement assistance device. This paper presents the design of a lower-limb exosuit designed to provide the wearer with useful gait assistance. While exoskeletons have existed for a while, soft exoskeletons or exosuits are relatively new. One challenge in the design of a gait-assistance device is the reduction of device weight. In order to facilitate this, the concept of kinematic synergies is implemented to reduce the number of actuators. In this prototype, the exosuit can actuate the hip, ankle, and knee of both legs using just one single motor, and a transmission system consisting of gears and clutches. The implementation of these synergies and their advantages are detailed in this paper, as well as preliminary tests to assess performance. This was performed by testing the exosuit worn by a subject on a treadmill while taking EMG readings and measuring cable tension produced. Significant reductions by up to 35% in certain muscle activations were observed, demonstrating the validity of this prototype for gait assistance. Full article

(This article belongs to the Special Issue Actuation Solutions for Wearable Robots)

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14 pages, 4135 KiB

Open AccessArticle

Dynamic Performance of a Magnetic Energy-Harvesting Suspension: Analysis and Experimental Verification

by Ran Zhou, Yuanyuan Song, Junjie Jin, Fangchao Xu, Feng Sun, Lijian Yang and Mingyin Yan

Actuators 2023, 12(8), 308; https://doi.org/10.3390/act12080308 - 27 Jul 2023

Viewed by 1058

Abstract

The advantages of the proposed novel magnetic energy-harvesting suspension (MEHS) are high safety, compact structure and convenient maintenance, compared with the previous studies. However, the force generated by the energy harvester with harvesting energy can affect the motion of the mechanical system. Therefore, [...] Read more.

The advantages of the proposed novel magnetic energy-harvesting suspension (MEHS) are high safety, compact structure and convenient maintenance, compared with the previous studies. However, the force generated by the energy harvester with harvesting energy can affect the motion of the mechanical system. Therefore, this paper aims to analyze the ride comfort and road handling of the MEHS, and investigates the dynamic performance of the MEHS. Firstly, the structure and the working principle of the MEHS are illustrated and introduced, and the dynamic mechanism of the quarter-vehicle with the MEHS is revealed and investigated. Secondly, the effects of the electromechanical coupling coefficient and external load resistance on the dynamic performance are investigated by numerical calculation. An experimental setup is established to verify the dynamic performance of the proposed MEHS. According to the experimental results, the dynamic performance of the suspension is contradictory with the increase of the external load resistance at the periodic frequency 7 Hz. And compared with the passive suspension, the dynamic performance of the MEHS is changed at various excitations, in which the sprung displacement and relative dynamic load of the tire of MEHS at the periodic frequency 3.3 Hz are reduced by 39.45% and 41.18%, respectively. Overall, the external load resistance of the proposed MEHS can be utilized to realize the variable damping of the suspension system and reduce the effect of vibration on the suspension system at the resonance frequency. And the dynamic performance has been verified in the laboratory, which lays the foundation for the dynamic analysis in a real vehicle. Full article

(This article belongs to the Special Issue Vibration Control Using Electromagnetic Actuators)

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Actuators, Volume 12, Issue 8 (August 2023) – 35 articles

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