Mechatronics最新文献_第5页

Multiple model switched repetitive control for tremor suppression 多模型切换重复控制抑制震颤

IF 3.1 3区计算机科学 Q2 AUTOMATION & CONTROL SYSTEMS

Mechatronics

Pub Date : 2025-08-05 DOI: 10.1016/j.mechatronics.2025.103392

Tingze Fang, Christopher T. Freeman

Tremor is a condition that impacts millions of people globally, and is characterised by a periodic limb movement that impedes voluntary motion. Recent studies have shown that functional electrical stimulation (FES) can help reduce tremor by artificially stimulating opposing muscles, thereby decreasing the oscillation’s amplitude. Various control methods have been proposed for this purpose, but repetitive control (RC) has shown the most promise with potential to completely suppress the tremor. While several RC approaches have demonstrated suppression rates of up to 90%, they heavily rely on an accurate model of the underlying dynamics, and their effectiveness declines steeply due to factors like muscle fatigue, spasticity, and modelling inaccuracies.

This paper introduces a multiple model switched repetitive control (MMSRC) framework that addresses the limitations of existing RC approaches. It guarantees high performance tremor suppression provided the true dynamics belong to an uncertainty set specified by the designer. This enables it to adapt to time-varying physiological changes, as well as changes in the placement of the FES electrodes. Moreover, once an uncertainty set has been established, it removes the need for subsequent model identification. This is an important step towards home-based tremor suppression where model identification and expert tuning are not possible. Experimental validation is performed with four participants, showing that MMSRC effectively suppresses tremor even in the presence of severe modelling uncertainty and fatigue, unlike conventional RC methods which often become unstable under these conditions.

震颤是一种影响全球数百万人的疾病，其特征是周期性肢体运动，阻碍了自主运动。最近的研究表明，功能性电刺激（FES）可以通过人工刺激对侧肌肉来减少震颤，从而降低振荡的幅度。为此提出了各种控制方法，但重复控制（RC）显示出最有希望完全抑制震颤的潜力。虽然一些RC方法已经证明抑制率高达90%，但它们严重依赖于潜在动力学的准确模型，并且由于肌肉疲劳、痉挛和建模不准确等因素，它们的有效性急剧下降。本文介绍了一个多模型切换重复控制（MMSRC）框架，解决了现有RC方法的局限性。它保证高性能的震颤抑制提供了真正的动态属于一个不确定的设计者指定的集合。这使得它能够适应时变的生理变化，以及FES电极位置的变化。此外，一旦建立了不确定性集，就不需要后续的模型识别。这是迈向基于家庭的震颤抑制的重要一步，其中模型识别和专家调谐是不可能的。实验验证与四名参与者进行，表明MMSRC有效地抑制震颤，即使存在严重的建模不确定性和疲劳，不像传统的RC方法，往往在这些条件下变得不稳定。

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引用次数: 0

Optimization of crutch-free walking for a powered exoskeleton considering human adaptation 考虑人类适应性的动力外骨骼无拐杖行走优化

IF 3.1 3区计算机科学 Q2 AUTOMATION & CONTROL SYSTEMS

Mechatronics

Pub Date : 2025-08-05 DOI: 10.1016/j.mechatronics.2025.103389

Jongwon Kim , Abhiraj Singh , Jimin Youn , Hyeongjun Kim , Jeongsu Park , Jinsu Park , Kyoungchul Kong

In crutch-free walking with powered exoskeletons, pilots instinctively engage their upper body to adapt its motion and maintain balance, especially in the absence of lower-limb sensory feedback or external stabilizing aids. These self-balancing efforts, often involving significant head and trunk movement, not only increase physical and cognitive load but also reduce the overall usability of the exoskeleton. This study proposes a human-adaptation-in-the-loop optimization method that minimizes the need for voluntary upper-body adjustments, particularly head movement. This approach aims to enable crutch-free walking by minimizing the pilot’s voluntary balancing, achieved through the iterative optimization of ankle joint trajectory based on the modeling of the pilot’s head movements and the center of pressure (COP). As a result, the proposed human-adaptation-in-the-loop optimization minimized the instability caused by the pilot’s adaptation motion that is not reflected within the human–robot integrated system, enabling continuous walking for people with spinal cord injury (SCI) at a speed of 0.24 m/s without the use of crutches. This demonstrates an effective solution for achieving natural, crutch-free walking in a powered exoskeleton.

在使用动力外骨骼的无拐杖行走中，飞行员本能地使用上半身来适应运动并保持平衡，特别是在没有下肢感官反馈或外部稳定辅助的情况下。这些自我平衡的努力，通常涉及显著的头部和躯干运动，不仅增加了身体和认知负荷，而且降低了外骨骼的整体可用性。本研究提出了一种人类适应循环优化方法，该方法可以最大限度地减少对上半身自愿调整的需要，特别是头部运动。该方法旨在通过基于飞行员头部运动和压力中心（COP）建模的踝关节轨迹迭代优化，最大限度地减少飞行员的自主平衡，从而实现无拐杖行走。因此，本文提出的人类自适应环内优化最小化了飞行员自适应运动在人-机器人集成系统中没有反映出来的不稳定性，使脊髓损伤（SCI）患者能够在不使用拐杖的情况下以0.24 m/s的速度连续行走。这展示了一种有效的解决方案，可以在动力外骨骼中实现自然的、无拐杖的行走。

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引用次数: 0

Research on space proximity pursuit-evasion interception decision-making based on deep reinforcement learning 基于深度强化学习的空间接近追逃拦截决策研究

IF 3.1 3区计算机科学 Q2 AUTOMATION & CONTROL SYSTEMS

Mechatronics

Pub Date : 2025-08-05 DOI: 10.1016/j.mechatronics.2025.103387

Cheng Huang, Quanli Zeng, Jiazhong Xu

Aiming at the one-to-one pursuit-evasion problem in space, to successfully intercept the close-range evader with arbitrary counter-maneuver under relative motion between pursuer and evader at a close given range, this paper proposes a decision-making method for close-range pursuit-evasion interception based on Distributed Distributional Deep Determined Policy Gradient (D4PG). An improved nearest neighbor algorithm exploration mechanism including random constant and logarithmic constant is adopted, which reduces the learning burden of the algorithm and improves its convergence stability. A target network containing three value networks is constructed, and the loss function is calculated by selecting a value network with the minimum variance of probability distribution in the three networks, which enables the more accurate estimation of the Q-functions, and the operation speed and efficiency of the algorithm are effectively improved. Four typical escaping scenarios of arbitrary counter-maneuvering are performed as experimental verification to the simulation, and the results show the effectiveness and superiority of the proposed decision-making method for space proximity pursuit-evasion interception.

针对空间中一对一的追逃问题，为了在给定近距离内，在追逃相对运动条件下成功拦截具有任意反机动的近距离躲避机，提出了一种基于分布式深度确定策略梯度（D4PG）的近距离追逃拦截决策方法。采用改进的包含随机常数和对数常数的最近邻算法探索机制，减少了算法的学习负担，提高了算法的收敛稳定性。构造了包含三个值网络的目标网络，通过选择三个网络中概率分布方差最小的值网络来计算损失函数，使得q函数的估计更加准确，有效地提高了算法的运算速度和效率。通过四种典型的任意反机动逃离场景对仿真进行了实验验证，结果表明了所提决策方法在空间近距离追逃拦截中的有效性和优越性。

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引用次数: 0

A novel pose control framework and its implementation for robot manipulators following constrained spatial paths 基于约束空间路径的机器人姿态控制框架及其实现

IF 3.1 3区计算机科学 Q2 AUTOMATION & CONTROL SYSTEMS

Mechatronics

Pub Date : 2025-07-31 DOI: 10.1016/j.mechatronics.2025.103390

Yalun Wen, Prabhakar R. Pagilla

This paper develops a novel pose control framework for robot manipulators traversing a given spatial curve with constant speed. The key to this framework is the use of a Rotation Minimizing Frame (RMF) for path generation and control, enhancing motion stability for paths with significant curvature and inflection points, and reducing kinematic twist. Using the governing equations based on the RMF, we first develop the reference velocity and acceleration along the path that is consistent with the RMF. Employing tools from differential geometry, we derive a path following position control law by projecting the robot translation states onto the RMF. From an analytical description of the relative orientation error kinematics, we derive a stabilizing orientation controller by utilizing the Modified Rodrigues Parameters to avoid the unwinding problem. The proposed framework is applicable to both torque-controlled and velocity-controlled robots, and we provide results from real-time experiments on both types of robots to verify the effectiveness and advantages of the proposed approach.

本文提出了一种新的机器人姿态控制框架，用于机器人以等速穿越给定的空间曲线。该框架的关键是使用旋转最小化框架（RMF）进行路径生成和控制，增强具有显著曲率和拐点的路径的运动稳定性，并减少运动学扭曲。利用基于RMF的控制方程，首先推导出与RMF一致的参考速度和参考加速度。利用微分几何工具，通过将机器人的平移状态投影到RMF上，推导出路径跟随位置控制律。从相对姿态误差运动学的分析描述出发，利用修正罗德里格斯参数推导出一种稳定姿态控制器，以避免解卷问题。所提出的框架适用于转矩控制和速度控制的机器人，并提供了两种类型机器人的实时实验结果，以验证所提出方法的有效性和优势。

引用次数: 0

Proving the stability of cycle navigation using capture sets 利用捕获集证明循环导航的稳定性

IF 3.1 3区计算机科学 Q2 AUTOMATION & CONTROL SYSTEMS

Mechatronics

Pub Date : 2025-07-31 DOI: 10.1016/j.mechatronics.2025.103385

Quentin Brateau, Loïck Degorre, Fabrice Le Bars, Luc Jaulin

Navigating Autonomous Underwater Vehicles (AUVs) presents significant challenges due to the absence of traditional localization systems. Cycle navigation emerges as a promising paradigm, enabling reliable navigation using minimal exteroceptive measurements. This approach leverages predefined cyclic trajectories, which are stabilized based on environmental feedback, ensuring frugal and discreet operations without reliance on high computational power or extensive sensor systems. This work aims to prove the stability of the cycle navigation. As cycle navigation is a non-linear system governed by a discrete inclusion condition, conventional methods have trouble to prove its stability. For this reason, this paper focuses on set methods to prove the stability of cycle navigation. The stability is proven by exhibiting a positive invariant set, which is a set stable by application of the evolution function of the system. This ensures that the evolution function will not remove states from the positively invariant set. Then, the characterization of the capture basin is an asset when performing cycle navigation, as it represents the set of initial states for the system which leads to the positive invariant set. Once the system reaches either the capture basin or the positive invariant set, which are generalized as a capture set, it remains captured forever. This approach not only guarantees the stability of the system in the neighborhood of the equilibrium point, but also establishes that it exists an area in which the stability of the cycle navigation will lead to a stable behavior. This work offers a robust, computationally efficient alternative to traditional stability methods, particularly suited for resource-constrained AUVs, because the underwater environment lacks suitable, cheap and easy-to-use localization methods, which forces us finding alternative ways to navigate and explore this particular environment.

由于缺乏传统的定位系统，自主水下航行器（auv）面临着巨大的挑战。循环导航作为一种很有前途的范例出现，使用最小的外感测量实现可靠的导航。这种方法利用预定义的循环轨迹，根据环境反馈稳定，确保节约和谨慎的操作，而不依赖于高计算能力或广泛的传感器系统。本工作旨在证明循环导航的稳定性。由于循环导航是一个由离散包含条件控制的非线性系统，常规方法难以证明其稳定性。因此，本文主要采用集合方法来证明循环导航的稳定性。通过构造一个正不变集来证明系统的稳定性，该正不变集是系统演化函数的稳定集。这确保了进化函数不会从正不变集中移除状态。然后，在执行循环导航时，捕获盆地的特征是一个资产，因为它代表了导致正不变集的系统的初始状态集。一旦系统达到捕获池或正不变集（广义为捕获集），它将永远保持捕获状态。该方法不仅保证了系统在平衡点附近的稳定性，而且证明了系统存在一个区域，在该区域内循环导航的稳定性会导致系统的稳定行为。这项工作为传统的稳定性方法提供了一种强大的、计算效率高的替代方法，特别适用于资源受限的auv，因为水下环境缺乏合适、廉价和易于使用的定位方法，这迫使我们寻找替代方法来导航和探索这种特定环境。

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引用次数: 0

Development of a type of cross-scale piezoelectric screw motor operating in quasi-static and resonant states 一种准静态和谐振型跨尺度压电螺杆电机的研制

IF 3.1 3区计算机科学 Q2 AUTOMATION & CONTROL SYSTEMS

Mechatronics

Pub Date : 2025-07-26 DOI: 10.1016/j.mechatronics.2025.103391

Xiaolong Shu , Yifang Zhang , Jianfa Lin , Bingliang Guan , Min Qian , Qiaosheng Pan

In this study, a cross-scale piezoelectric screw motor was proposed, designed, fabricated and tested. The proposed motor can operate in quasi-static and resonant states, and achieves cross-scale motion output through mode conversion. The motor is comprised of a stator and a rotor, with the same internal and external screws. The motor’s motion is achieved by friction between the stator and the rotor. Structure and working principle of the motor are introduced. The vibration modes of the stator in different modes were studied through finite element analysis. The motor's dynamic model was established. Finally, the prototype was fabricated, and the output performance was tested. Experimental results demonstrate a minimum resolution of 12.5 nm and a maximum load capacity of 12 N in quasi-static mode. When operating in resonant state, the motor achieves a maximum speed of 10.4mm/min (32.8 rpm), the maximum load capacity is 30 N and the maximum efficiency is 0.36 % when the prototype is rotated forward. When the motor is reversed, the maximum speed is 20.8 mm/min (65.5 rpm), the load capacity reaches 33 N, and the maximum efficiency is 0.46 %. The proposed piezoelectric motor promotes the development of cross-scale actuators.

本研究提出、设计、制作并测试了一种跨尺度压电螺旋电机。该电机可以在准静态和谐振状态下工作，并通过模式转换实现跨尺度运动输出。电机由定子和转子组成，内部和外部有相同的螺钉。电动机的运动是通过定子和转子之间的摩擦来实现的。介绍了电机的结构和工作原理。通过有限元分析，研究了定子在不同模态下的振动模态。建立了电机的动力学模型。最后制作了样机，并对输出性能进行了测试。实验结果表明，在准静态模式下，最小分辨率为12.5 nm，最大负载能力为12 N。在谐振状态下运行时，样机向前旋转时，电机最大转速为10.4mm/min (32.8 rpm)，最大负载能力为30 N，最大效率为0.36%。电机倒转时，最高转速20.8 mm/min (65.5 rpm)，负载能力达到33 N，最高效率为0.46%。提出的压电电机促进了跨尺度作动器的发展。

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引用次数: 0

Efficient avoidance of ellipsoidal obstacles with model predictive control for mobile robots and vehicles 基于模型预测控制的移动机器人和车辆椭球体障碍物有效避障

IF 3.1 3区计算机科学 Q2 AUTOMATION & CONTROL SYSTEMS

Mechatronics

Pub Date : 2025-07-21 DOI: 10.1016/j.mechatronics.2025.103386

Mario Rosenfelder , Hendrik Carius , Markus Herrmann-Wicklmayr , Peter Eberhard , Kathrin Flaßkamp , Henrik Ebel

In real-world applications of mobile robots, collision avoidance is of critical importance. Typically, global motion planning in constrained environments is addressed through high-level control schemes. However, additionally integrating local collision avoidance into robot motion control offers significant advantages. For instance, it reduces the reliance on heuristics, conservatism, and complexity from additional hyperparameters that can arise from a two-stage approach separating local collision avoidance and control. Moreover, using model predictive control (MPC), a robot’s full potential can be harnessed by considering jointly local collision avoidance, the robot’s dynamics including dynamic constraints (like nonholonomic constraints), and actuation constraints. In this context, the present paper focuses on local obstacle avoidance for wheeled mobile robots, where both the robot’s and obstacles’ occupied volumes are modeled as ellipsoids of arbitrary orientation. To this end, a computationally efficient overlap test, which works for arbitrary ellipsoids, is conducted and novelly integrated into the MPC framework. We propose a particularly efficient implementation tailored to robots moving in the plane. The functionality of the proposed obstacle-avoiding MPC is demonstrated for two exemplary types of kinematics by means of simulations. A hardware experiment using a real-world wheeled mobile robot shows transferability to reality and real-time applicability. Moreover, numerical experiments show that, due to the approach’s general nature, it can be directly applied to dynamic situations like moving obstacles. The general computational approach to ellipsoidal obstacle avoidance can also be applied to other robotic systems and vehicles as well as three-dimensional scenarios.

在移动机器人的实际应用中，避碰是至关重要的。通常，约束环境中的全局运动规划是通过高级控制方案解决的。然而，将局部避碰集成到机器人运动控制中具有显著的优势。例如，它减少了对启发式、保守性和额外超参数的依赖，这些超参数可能来自分离局部冲突避免和控制的两阶段方法。此外，利用模型预测控制（MPC），通过联合考虑局部避碰、机器人动力学包括动力学约束（如非完整约束）和驱动约束，可以充分利用机器人的潜力。在这种情况下，本文主要研究轮式移动机器人的局部避障问题，其中机器人和障碍物的占用体积都被建模为任意方向的椭球体。为此，进行了一种计算效率高的、适用于任意椭球体的重叠测试，并将其新颖地集成到MPC框架中。我们提出了一种特别有效的实现，专门针对在平面上移动的机器人。通过仿真验证了所提出的避障MPC的两种典型运动学类型的功能。利用实际轮式移动机器人进行硬件实验，验证了其可移植性和实时性。此外，数值实验表明，由于该方法的通用性，可以直接应用于移动障碍物等动态情况。椭球避障的一般计算方法也可以应用于其他机器人系统和车辆以及三维场景。

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引用次数: 0

Novel design of GFRP beam spring rocker-arm suspension for 6-wheeled mobile robots 6轮移动机器人GFRP梁弹簧摇臂悬架的新设计

IF 3.1 3区计算机科学 Q2 AUTOMATION & CONTROL SYSTEMS

Mechatronics

Pub Date : 2025-07-16 DOI: 10.1016/j.mechatronics.2025.103388

Gunwoo An, Jaeyoung Kang

Six-wheeled mobile robots (6-WMRs) equipped with rocker-bogie suspension systems are widely used for planetary exploration and search-and-rescue tasks due to their excellent terrain adaptability. However, conventional rocker-bogie-based systems present critical limitations, including tire slip caused by the absence of steering mechanisms, lack of camber control, and increased structural complexity from added components. To overcome these issues, this study introduces the GFRP Beam Spring Rocker-arm Suspension (GBSRS), which integrates a rocker-arm structure with a Glass Fiber Reinforced Polymer (GFRP) beam spring. An independent steering system based on Ackermann geometry is applied to minimize tire slip, while the torsional and vertical compliance of the GFRP beam enables passive camber variation and vibration damping without the use of additional actuators or complex linkages. A 7-degree-of-freedom (7-DOF) vibration model is developed to simulate dynamic behavior, and a bend-twist coupling analysis is conducted to calculate beam deformation and camber response. The design is further optimized by applying Derringer’s desirability function to key parameters such as beam thickness, damper position, and camber adjuster angle. Simulation and experimental results—including tests over single obstacles and rough terrain—demonstrate that the GBSRS reduces RMS acceleration by up to 16.3% and peak acceleration by up to 40.6% compared to conventional solid-arm systems. These results confirm that the GBSRS effectively improves vibration isolation and camber adaptability while maintaining structural simplicity, offering a practical suspension solution for 6-WMRs in challenging environments.

采用摇臂-转向架悬挂系统的六轮移动机器人由于具有良好的地形适应性，被广泛应用于行星探测和搜救任务中。然而，传统的摇臂转向架系统存在严重的局限性，包括由于缺乏转向机构而导致的轮胎打滑，缺乏弧度控制，以及增加组件增加的结构复杂性。为了克服这些问题，本研究引入了GFRP梁弹簧摇臂悬架（GBSRS），该悬架将摇臂结构与玻璃纤维增强聚合物（GFRP）梁弹簧集成在一起。基于Ackermann几何结构的独立转向系统可以最大限度地减少轮胎打滑，而GFRP梁的扭转和垂直顺应性可以实现被动弧度变化和振动阻尼，而无需使用额外的执行器或复杂的连接。建立了7自由度（7-DOF）振动模型，模拟了梁的动力特性，并进行了弯扭耦合分析，计算了梁的变形和弯曲响应。通过应用Derringer期望函数对梁厚度、阻尼器位置和弧度调节器角度等关键参数进行优化设计。仿真和实验结果（包括在单一障碍物和崎岖地形上的测试）表明，与传统的固体臂系统相比，GBSRS的均方根加速度可降低16.3%，峰值加速度可降低40.6%。这些结果证实，GBSRS在保持结构简单的同时，有效地提高了隔振性和弧度适应性，为6- wmr在具有挑战性的环境中提供了一种实用的悬架解决方案。

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引用次数: 0

Digital human model and training task planning-based adaptive assist-as-needed control for upper limb exoskeleton 基于数字人体模型和训练任务规划的上肢外骨骼自适应辅助控制

IF 3.1 3区计算机科学 Q2 AUTOMATION & CONTROL SYSTEMS

Mechatronics

Pub Date : 2025-07-12 DOI: 10.1016/j.mechatronics.2025.103381

Jiazhen Xu, Haoping Wang, Yang Tian

To address the challenges of diminished motivation and increased fatigue observed in participants during active rehabilitation training, this study proposes a digital human model-based adaptive assist-as-needed (DHM-AAAN) control for an upper limb exoskeleton. This control framework consists of two main sub-controller loops: an outer sub-controller loop that determines the necessary assistive force, and an inner sub-controller loop which enables the exoskeleton to accurately replicate target movements while applying the assistive force derived from the outer sub-controller loop. Within the outer sub-controller loop, a strategy known as the digital human model and task performance evaluation (DHM-TPE) is employed to evaluate participants’ mobility capabilities and overall condition. Based on the assessment results, parameters such as radius, frequency, and assistive force are dynamically adjusted for multi-period trajectory tracking tasks through the implementation of an adaptive frequency oscillator (AFO) algorithm integrated with a digital human model. In the inner sub-controller loop, a barrier Lyapunov function-based hybrid force/position control with shifting error constraints (BLF-HCS) controller is introduced. This controller utilizes radial basis function neural networks (RBFNN) and error offset functions initialized with random values. The BLF constrains the exoskeleton’s tracking error, considering potential deviations from the desired initial position during the early phases of movement. To validate the effectiveness of the proposed controller, this study presents joint simulation results of the rehabilitation training cycle for circular task trajectories, experimental results from individual participants, and the average results from 6 participants.

为了解决在主动康复训练中观察到的参与者动力下降和疲劳增加的挑战，本研究提出了一种基于数字人体模型的上肢外骨骼自适应辅助（DHM-AAAN）控制。该控制框架由两个主要的子控制器环组成：一个外部子控制器环决定必要的辅助力，一个内部子控制器环使外骨骼能够准确地复制目标运动，同时应用来自外部子控制器环的辅助力。在外部子控制器回路中，采用数字人体模型和任务绩效评估（DHM-TPE）策略来评估参与者的移动能力和整体状况。基于评估结果，通过实现与数字人体模型相结合的自适应频率振荡器（AFO）算法，对多周期轨迹跟踪任务的半径、频率和辅助力等参数进行动态调整。在子控制器内环中，引入了一种基于barrier Lyapunov函数的带移位误差约束的混合力/位置控制（BLF-HCS）控制器。该控制器采用径向基函数神经网络（RBFNN）和随机初始化误差补偿函数。考虑到在运动的早期阶段与期望初始位置的潜在偏差，BLF限制了外骨骼的跟踪误差。为了验证所提出控制器的有效性，本研究给出了圆形任务轨迹的康复训练周期联合仿真结果、个体参与者的实验结果以及6名参与者的平均结果。

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引用次数: 0

Corrigendum to “A real-time lane change trajectory planning approach for autonomous vehicles utilizing tire force prediction” [Mechatronics 109 (2025) 103351] “基于轮胎力预测的自动驾驶车辆实时变道轨迹规划方法”[机电一体化]109(2025)103351]更正

IF 3.1 3区计算机科学 Q2 AUTOMATION & CONTROL SYSTEMS

Mechatronics

Pub Date : 2025-07-12 DOI: 10.1016/j.mechatronics.2025.103383

Lin Li , Serdar Coskun , Youming Fan , Caiguang Yu , Fengqi Zhang

引用次数: 0