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Search Results (611)

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14 pages, 692 KB  
Systematic Review
Image-Based Robotic Unicompartmental Knee Arthroplasty Results in Fewer Radiologic Outliers with No Impact on Revision Rates Compared to Imageless Systems: A Systematic Review
by Horia Tomescu, George M. Avram, Giacomo Pacchiarotti, Randa Elsheikh, Octav Russu, Andrej M. Nowakowski, Michael T. Hirschmann and Vlad Predescu
J. Clin. Med. 2025, 14(17), 5996; https://doi.org/10.3390/jcm14175996 (registering DOI) - 25 Aug 2025
Abstract
Background: Robotic-assisted unicompartmental knee arthroplasty (UKA) enhances the precision of component alignment compared to conventional techniques. Although various robotic systems exist, direct comparisons assessing their relative clinical performance remain limited. The purpose of this study is to provide a comparison between image-based [...] Read more.
Background: Robotic-assisted unicompartmental knee arthroplasty (UKA) enhances the precision of component alignment compared to conventional techniques. Although various robotic systems exist, direct comparisons assessing their relative clinical performance remain limited. The purpose of this study is to provide a comparison between image-based and imageless robotic UKA. Methods: A systematic review was conducted in accordance with PRISMA guidelines. Five databases were searched: PubMed (via MEDLINE), Epistemonikos, Cochrane Library, Web of Science, and Scopus. Inclusion criteria were (1) studies comparing rUKA and cUKA with radiologic parameters and revision rates (prospective or retrospective), (2) human subjects, (3) meta-analyses for cross-referencing, and (4) English language. Data collected included (1) pre- and postoperative radiologic parameters, (2) radiologic outliers, and (3) revisions and their causes. A random-effects meta-analysis was employed to enable a generalizable comparison. Mean differences (MDs) with 95% confidence intervals (CIs) were calculated for continuous variables, and log odds ratios (LORs) with 95% CIs for binary outcomes. Results: Image-based robotic UKA was associated with fewer joint line height outliers (LOR = 3.5, 95% CI: 0.69–6.30, p = 0.015) using a 2° threshold. HKA outliers (thresholds 2–3°) were also reduced (LOR = 0.6, 95% CI: 0.09–1.19, p = 0.024). Posterior tibial and posterior femoral implant fit were significantly lower with image-based systems (LOR = 1.7, 95% CI: 1.37–2.03, respectively, LOR = 1.7, 95% CI: 1.29–1.91; p < 0.001 for both). No significant differences in revision rates were observed. Conclusions: Image-based robotic systems may result in fewer outliers in key radiologic parameters, including hip–knee angle, joint-line height, posterior tibial, and posterior femoral fit, though reporting remains highly heterogeneous. Full article
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22 pages, 4034 KB  
Article
An Online Modular Framework for Anomaly Detection and Multiclass Classification in Video Surveillance
by Jonathan Flores-Monroy, Gibran Benitez-Garcia, Mariko Nakano-Miyatake and Hiroki Takahashi
Appl. Sci. 2025, 15(17), 9249; https://doi.org/10.3390/app15179249 - 22 Aug 2025
Viewed by 124
Abstract
Video surveillance systems are a key tool for the identification of anomalous events, but they still rely heavily on human analysis, which limits their efficiency. Current video anomaly detection models aim to automatically detect such events. However, most of them provide only a [...] Read more.
Video surveillance systems are a key tool for the identification of anomalous events, but they still rely heavily on human analysis, which limits their efficiency. Current video anomaly detection models aim to automatically detect such events. However, most of them provide only a binary classification (normal or anomalous) and do not identify the specific type of anomaly. Although recent proposals address anomaly classification, they typically require full video analysis, making them unsuitable for online applications. In this work, we propose a modular framework for the joint detection and classification of anomalies, designed to operate on individual clips within continuous video streams. The architecture integrates interchangeable modules (feature extractor, detector, and classifier) and is adaptable to both offline and online scenarios. Specifically, we introduce a multi-category classifier that processes only anomalous clips, enabling efficient clip-level classification. Experiments conducted on the UCF-Crime dataset validate the effectiveness of the framework, achieving 74.77% clip-level accuracy and 58.96% video-level accuracy, surpassing prior approaches and confirming its applicability in real-world surveillance environments. Full article
24 pages, 19432 KB  
Article
Robot Learning from Teleoperated Demonstrations: A Pilot Study Towards Automating Mastic Deposition in Construction Sites
by Irati Rasines, Erlantz Loizaga, Rebecca Erlebach, Anurag Bansal, Sara Sillaurren, Patricia Rosen, Sascha Wischniewski, Arantxa Renteria and Itziar Cabanes
Robotics 2025, 14(8), 114; https://doi.org/10.3390/robotics14080114 - 19 Aug 2025
Viewed by 327
Abstract
The construction industry faces significant challenges due to the physically demanding and hazardous nature of tasks such as manual filling of expansion joints with mastic. Automating mastic filling presents additional difficulties due to the variability of mastic density with temperature, which creates a [...] Read more.
The construction industry faces significant challenges due to the physically demanding and hazardous nature of tasks such as manual filling of expansion joints with mastic. Automating mastic filling presents additional difficulties due to the variability of mastic density with temperature, which creates a constantly changing environment that requires adaptive control strategies to ensure consistent application quality. This pilot study focuses on testing a new human–robot collaborative approach for automating the mastic application in concrete expansion joints. The system learns the task from demonstrations performed by expert construction operators teleoperating the robot. This study evaluates the usability, efficiency, and adoption of robotic assistance in joint-filling tasks compared to traditional manual methods. The study analyzes execution time and joint quality measurements, psychophysiological signal analysis, and post-task user feedback. This multi-source approach enables a comprehensive assessment of task performance and both objective and subjective evaluations of technology acceptance. The findings underscore the effectiveness of automated systems in improving safety and productivity on construction sites, while also identifying key areas for technological improvement. Full article
(This article belongs to the Section Industrial Robots and Automation)
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14 pages, 1167 KB  
Article
REEV SENSE IMUs for Gait Analysis in Stroke: A Clinical Study on Lower Limb Kinematics
by Thibault Marsan, Sacha Clauzade, Xiang Zhang, Nicolas Grandin, Tatiana Urman, Evan Linton, Ingy Elsayed-Aly, Catherine E. Ricciardi and Robin Temporelli
Sensors 2025, 25(16), 5123; https://doi.org/10.3390/s25165123 - 18 Aug 2025
Viewed by 306
Abstract
Human gait analysis is essential for clinical evaluation and rehabilitation monitoring, particularly in post-stroke individuals, where joint kinematics provide valuable insights into motor recovery. While optical motion capture (OMC) is the gold standard, its high cost and restricted use in laboratory settings limit [...] Read more.
Human gait analysis is essential for clinical evaluation and rehabilitation monitoring, particularly in post-stroke individuals, where joint kinematics provide valuable insights into motor recovery. While optical motion capture (OMC) is the gold standard, its high cost and restricted use in laboratory settings limit its accessibility. This study aimed to evaluate the accuracy of REEV SENSE, a novel magnetometer-free inertial measurement unit (IMU), in capturing knee and ankle joint angles during overground walking in post-stroke individuals using assistive devices. Twenty participants with chronic stroke walked along a 10-m walkway with their usual assistive device (cane or walker), while joint kinematics were simultaneously recorded using OMC and IMUs. Agreement between the systems was assessed using the mean absolute error, root mean square error, 95% confidence intervals, and Pearson’s correlation coefficient. Knee angles measured with the IMUs showed a strong correlation with the OMC (r > 0.9) and low errors (MAE < 5°), consistent with clinical acceptability. Ankle angle accuracy was lower for participants using walkers, while knee measurements remained stable regardless of the assistive device. These findings demonstrate that REEV SENSE IMUs provide clinically relevant kinematic data and support their use as a practical wearable tool for gait analysis in real-world or remote clinical settings. Full article
(This article belongs to the Special Issue Wearable Inertial Sensors for Human Movement Analysis)
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34 pages, 11523 KB  
Article
Hand Kinematic Model Construction Based on Tracking Landmarks
by Yiyang Dong and Shahram Payandeh
Appl. Sci. 2025, 15(16), 8921; https://doi.org/10.3390/app15168921 - 13 Aug 2025
Viewed by 252
Abstract
Visual body-tracking techniques have seen widespread adoption in applications such as motion analysis, human–machine interaction, tele-robotics and extended reality (XR). These systems typically provide 2D landmark coordinates corresponding to key limb positions. However, to construct a meaningful 3D kinematic model for body joint [...] Read more.
Visual body-tracking techniques have seen widespread adoption in applications such as motion analysis, human–machine interaction, tele-robotics and extended reality (XR). These systems typically provide 2D landmark coordinates corresponding to key limb positions. However, to construct a meaningful 3D kinematic model for body joint reconstruction, a mapping must be established between these visual landmarks and the underlying joint parameters of individual body parts. This paper presents a method for constructing a 3D kinematic model of the human hand using calibrated 2D landmark-tracking data augmented with depth information. The proposed approach builds a hierarchical model in which the palm serves as the root coordinate frame, and finger landmarks are used to compute both forward and inverse kinematic solutions. Through step-by-step examples, we demonstrate how measured hand landmark coordinates are used to define the palm reference frame and solve for joint angles for each finger. These solutions are then used in a visualization framework to qualitatively assess the accuracy of the reconstructed hand motion. As a future work, the proposed model offers a foundation for model-based hand kinematic estimation and has utility in scenarios involving occlusion or missing data. In such cases, the hierarchical structure and kinematic solutions can be used as generative priors in an optimization framework to estimate unobserved landmark positions and joint configurations. The novelty of this work lies in its model-based approach using real sensor data, without relying on wearable devices or synthetic assumptions. Although current validation is qualitative, the framework provides a foundation for future robust estimation under occlusion or sensor noise. It may also serve as a generative prior for optimization-based methods and be quantitatively compared with joint measurements from wearable motion-capture systems. Full article
(This article belongs to the Special Issue Human Activity Recognition (HAR) in Healthcare, 3rd Edition)
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19 pages, 7780 KB  
Article
Posture Estimation from Tactile Signals Using a Masked Forward Diffusion Model
by Sanket Kachole, Bhagyashri Nayak, James Brouner, Ying Liu, Liucheng Guo and Dimitrios Makris
Sensors 2025, 25(16), 4926; https://doi.org/10.3390/s25164926 - 9 Aug 2025
Viewed by 316
Abstract
Utilizing tactile sensors embedded in intelligent mats is an attractive non-intrusive approach for human motion analysis. Interpreting tactile pressure 2D maps for accurate posture estimation poses significant challenges, such as dealing with data sparsity, noise interference, and the complexity of mapping pressure signals. [...] Read more.
Utilizing tactile sensors embedded in intelligent mats is an attractive non-intrusive approach for human motion analysis. Interpreting tactile pressure 2D maps for accurate posture estimation poses significant challenges, such as dealing with data sparsity, noise interference, and the complexity of mapping pressure signals. Our approach introduces a novel dual-diffusion signal enhancement (DDSE) architecture that leverages tactile pressure measurements from an intelligent pressure mat for precise prediction of 3D body joint positions, using a diffusion model to enhance pressure data quality and a convolutional-transformer neural network architecture for accurate pose estimation. Additionally, we collected the pressure-to-posture inference technology (PPIT) dataset that relates pressure signals organized as a 2D array to Motion Capture data, and our proposed method has been rigorously evaluated on it, demonstrating superior accuracy in comparison to state-of-the-art methods. Full article
(This article belongs to the Section Physical Sensors)
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39 pages, 3756 KB  
Review
Nanocarriers Containing Curcumin and Derivatives for Arthritis Treatment: Mapping the Evidence in a Scoping Review
by Beatriz Yurie Sugisawa Sato, Susan Iida Chong, Nathalia Marçallo Peixoto Souza, Raul Edison Luna Lazo, Roberto Pontarolo, Fabiane Gomes de Moraes Rego, Luana Mota Ferreira and Marcel Henrique Marcondes Sari
Pharmaceutics 2025, 17(8), 1022; https://doi.org/10.3390/pharmaceutics17081022 - 6 Aug 2025
Viewed by 475
Abstract
Background/Objectives: Curcumin (CUR) is well known for its therapeutic properties, particularly attributed to its antioxidant and anti-inflammatory effects in managing chronic diseases such as arthritis. While CUR application for biomedical purposes is well known, the phytochemical has several restrictions given its poor water [...] Read more.
Background/Objectives: Curcumin (CUR) is well known for its therapeutic properties, particularly attributed to its antioxidant and anti-inflammatory effects in managing chronic diseases such as arthritis. While CUR application for biomedical purposes is well known, the phytochemical has several restrictions given its poor water solubility, physicochemical instability, and low bioavailability. These limitations have led to innovative formulations, with nanocarriers emerging as a promising alternative. For this reason, this study aimed to address the potential advantages of associating CUR with nanocarrier systems in managing arthritis through a scoping review. Methods: A systematic literature search of preclinical (in vivo) and clinical studies was performed in PubMed, Scopus, and Web of Science (December 2024). General inclusion criteria include using CUR or natural derivatives in nano-based formulations for arthritis treatment. These elements lead to the question: “What is the impact of the association of CUR or derivatives in nanocarriers in treating arthritis?”. Results: From an initial 536 articles, 34 were selected for further analysis (31 preclinical investigations and three randomized clinical trials). Most studies used pure CUR (25/34), associated with organic (30/34) nanocarrier systems. Remarkably, nanoparticles (16/34) and nanoemulsions (5/34) were emphasized. The formulations were primarily presented in liquid form (23/34) and were generally administered to animal models through intra-articular injection (11/31). Complete Freund’s Adjuvant (CFA) was the most frequently utilized among the various models to induce arthritis-like joint damage. The findings indicate that associating CUR or its derivatives with nanocarrier systems enhances its pharmacological efficacy through controlled release and enhanced solubility, bioavailability, and stability. Moreover, the encapsulation of CUR showed better results in most cases than in its free form. Nonetheless, most studies were restricted to the preclinical model, not providing direct evidence in humans. Additionally, inadequate information and clarity presented considerable challenges for preclinical evidence, which was confirmed by SYRCLE’s bias detection tools. Conclusions: Hence, this scoping review highlights the anti-arthritic effects of CUR nanocarriers as a promising alternative for improved treatment. Full article
(This article belongs to the Special Issue Advances in Polymer-Based Devices and Platforms for Pain Management)
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20 pages, 15898 KB  
Article
Design of a Humanoid Upper-Body Robot and Trajectory Tracking Control via ZNN with a Matrix Derivative Observer
by Hong Yin, Hongzhe Jin, Yuchen Peng, Zijian Wang, Jiaxiu Liu, Fengjia Ju and Jie Zhao
Biomimetics 2025, 10(8), 505; https://doi.org/10.3390/biomimetics10080505 - 2 Aug 2025
Viewed by 631
Abstract
Humanoid robots have attracted considerable attention for their anthropomorphic structure, extended workspace, and versatile capabilities. This paper presents a novel humanoid upper-body robotic system comprising a pair of 8-degree-of-freedom (DOF) arms, a 3-DOF head, and a 3-DOF torso—yielding a 22-DOF architecture inspired by [...] Read more.
Humanoid robots have attracted considerable attention for their anthropomorphic structure, extended workspace, and versatile capabilities. This paper presents a novel humanoid upper-body robotic system comprising a pair of 8-degree-of-freedom (DOF) arms, a 3-DOF head, and a 3-DOF torso—yielding a 22-DOF architecture inspired by human biomechanics and implemented via standardized hollow joint modules. To overcome the critical reliance of zeroing neural network (ZNN)-based trajectory tracking on the Jacobian matrix derivative, we propose an integration-enhanced matrix derivative observer (IEMDO) that incorporates nonlinear feedback and integral correction. The observer is theoretically proven to ensure asymptotic convergence and enables accurate, real-time estimation of matrix derivatives, addressing a fundamental limitation in conventional ZNN solvers. Workspace analysis reveals that the proposed design achieves an 87.7% larger total workspace and a remarkable 3.683-fold expansion in common workspace compared to conventional dual-arm baselines. Furthermore, the observer demonstrates high estimation accuracy for high-dimensional matrices and strong robustness to noise. When integrated into the ZNN controller, the IEMDO achieves high-precision trajectory tracking in both simulation and real-world experiments. The proposed framework provides a practical and theoretically grounded approach for redundant humanoid arm control. Full article
(This article belongs to the Special Issue Bio-Inspired and Biomimetic Intelligence in Robotics: 2nd Edition)
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21 pages, 1306 KB  
Article
Dual Quaternion-Based Forward and Inverse Kinematics for Two-Dimensional Gait Analysis
by Rodolfo Vergara-Hernandez, Juan-Carlos Gonzalez-Islas, Omar-Arturo Dominguez-Ramirez, Esteban Rueda-Soriano and Ricardo Serrano-Chavez
J. Funct. Morphol. Kinesiol. 2025, 10(3), 298; https://doi.org/10.3390/jfmk10030298 - 1 Aug 2025
Viewed by 339
Abstract
Background: Gait kinematics address the analysis of joint angles and segment movements during walking. Although there is work in the literature to solve the problems of forward (FK) and inverse kinematics (IK), there are still problems related to the accuracy of the estimation [...] Read more.
Background: Gait kinematics address the analysis of joint angles and segment movements during walking. Although there is work in the literature to solve the problems of forward (FK) and inverse kinematics (IK), there are still problems related to the accuracy of the estimation of Cartesian and joint variables, singularities, and modeling complexity on gait analysis approaches. Objective: In this work, we propose a framework for two-dimensional gait analysis addressing the singularities in the estimation of the joint variables using quaternion-based kinematic modeling. Methods: To solve the forward and inverse kinematics problems we use the dual quaternions’ composition and Damped Least Square (DLS) Jacobian method, respectively. We assess the performance of the proposed methods with three gait patterns including normal, toe-walking, and heel-walking using the RMSE value in both Cartesian and joint spaces. Results: The main results demonstrate that the forward and inverse kinematics methods are capable of calculating the posture and the joint angles of the three-DoF kinematic chain representing a lower limb. Conclusions: This framework could be extended for modeling the full or partial human body as a kinematic chain with more degrees of freedom and multiple end-effectors. Finally, these methods are useful for both diagnostic disease and performance evaluation in clinical gait analysis environments. Full article
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18 pages, 4452 KB  
Article
Upper Limb Joint Angle Estimation Using a Reduced Number of IMU Sensors and Recurrent Neural Networks
by Kevin Niño-Tejada, Laura Saldaña-Aristizábal, Jhonathan L. Rivas-Caicedo and Juan F. Patarroyo-Montenegro
Electronics 2025, 14(15), 3039; https://doi.org/10.3390/electronics14153039 - 30 Jul 2025
Viewed by 499
Abstract
Accurate estimation of upper-limb joint angles is essential in biomechanics, rehabilitation, and wearable robotics. While inertial measurement units (IMUs) offer portability and flexibility, systems requiring multiple inertial sensors can be intrusive and complex to deploy. In contrast, optical motion capture (MoCap) systems provide [...] Read more.
Accurate estimation of upper-limb joint angles is essential in biomechanics, rehabilitation, and wearable robotics. While inertial measurement units (IMUs) offer portability and flexibility, systems requiring multiple inertial sensors can be intrusive and complex to deploy. In contrast, optical motion capture (MoCap) systems provide precise tracking but are constrained to controlled laboratory environments. This study presents a deep learning-based approach for estimating shoulder and elbow joint angles using only three IMU sensors positioned on the chest and both wrists, validated against reference angles obtained from a MoCap system. The input data includes Euler angles, accelerometer, and gyroscope data, synchronized and segmented into sliding windows. Two recurrent neural network architectures, Convolutional Neural Network with Long-short Term Memory (CNN-LSTM) and Bidirectional LSTM (BLSTM), were trained and evaluated using identical conditions. The CNN component enabled the LSTM to extract spatial features that enhance sequential pattern learning, improving angle reconstruction. Both models achieved accurate estimation performance: CNN-LSTM yielded lower Mean Absolute Error (MAE) in smooth trajectories, while BLSTM provided smoother predictions but underestimated some peak movements, especially in the primary axes of rotation. These findings support the development of scalable, deep learning-based wearable systems and contribute to future applications in clinical assessment, sports performance analysis, and human motion research. Full article
(This article belongs to the Special Issue Wearable Sensors for Human Position, Attitude and Motion Tracking)
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18 pages, 1696 KB  
Article
Concurrent Adaptive Control for a Robotic Leg Prosthesis via a Neuromuscular-Force-Based Impedance Method and Human-in-the-Loop Optimization
by Ming Pi
Appl. Sci. 2025, 15(15), 8126; https://doi.org/10.3390/app15158126 - 22 Jul 2025
Viewed by 329
Abstract
This paper proposes an adaptive human–robot concurrent control scheme that achieves the appropriate gait trajectory for a robotic leg prosthesis to improve the wearer’s comfort in various tasks. To accommodate different wearers, a neuromuscular-force-based impedance method was developed using muscle activation to reshape [...] Read more.
This paper proposes an adaptive human–robot concurrent control scheme that achieves the appropriate gait trajectory for a robotic leg prosthesis to improve the wearer’s comfort in various tasks. To accommodate different wearers, a neuromuscular-force-based impedance method was developed using muscle activation to reshape gait trajectory. To eliminate the use of sensors for torque measurement, a disturbance observer was established to estimate the interaction force between the human residual limb and the prosthetic receptacle. The cost function was combined with the interaction force and tracking errors of the joints. We aim to reduce the cost function by minimally changing the control weight of the gait trajectory generated by the Central Pattern Generator (CPG). The control scheme was primarily based on human-in-the-loop optimization to search for a suitable control weight to regenerate the appropriate gait trajectory. To handle the uncertainties and unknown coupling of the motors, an adaptive law was designed to estimate the unknown parameters of the system. Through a stability analysis, the control framework was verified by semi-globally uniformly ultimately bounded stability. Experimental results are discussed, and the effectiveness of the adaptive control framework is demonstrated. In Case 1, the mean error (MEAN) of the tracking performance was 3.6° and 3.3°, respectively. And the minimized mean square errors (MSEs) of the tracking performance were 2.3° and 2.8°, respectively. In Case 2, the mean error (MEAN) of the tracking performance is 2.7° and 3.1°, respectively. And the minimized mean square errors (MSEs) of the tracking performance are 1.8° and 2.4°, respectively. In Case 3, the mean errors (MEANs) of the tracking performance for subject1 and 2 are 2.4°, 2.9°, 3.4°, and 2.2°, 2.8°, 3.1°, respectively. The minimized mean square errors (MSEs) of the tracking performance for subject1 and 2 were 1.6°, 2.3°, 2.6°, and 1.3°, 1.7°, 2.2°, respectively. Full article
(This article belongs to the Section Robotics and Automation)
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17 pages, 2840 KB  
Article
A Digital Twin System for the Sitting-to-Standing Motion of the Knee Joint
by Tian Liu, Liangzheng Sun, Chaoyue Sun, Zhijie Chen, Jian Li and Peng Su
Electronics 2025, 14(14), 2867; https://doi.org/10.3390/electronics14142867 - 18 Jul 2025
Viewed by 418
Abstract
(1) Background: A severe decline in knee joint function significantly affects the mobility of the elderly, making it a key concern in the field of geriatric health. To alleviate the pressure on the knee joints of the elderly during daily movements such as [...] Read more.
(1) Background: A severe decline in knee joint function significantly affects the mobility of the elderly, making it a key concern in the field of geriatric health. To alleviate the pressure on the knee joints of the elderly during daily movements such as sitting and standing, effective biomechanical solutions are required. (2) Methods: In this study, a biomechanical framework was established based on mechanical analysis to derive the transfer relationship between the ground reaction force and the knee joint moment. Experiments were designed to collect knee joint data on the elderly during the sit-to-stand process. Meanwhile, magnetic resonance imaging (MRI) images were processed through a medical imaging control system to construct a detailed digital 3D knee joint model. A finite element analysis was used to verify the model to ensure the accuracy of its structure and mechanical properties. An improved radial basis function was used to fit the pressure during the entire sit-to-stand conversion process to reduce the computational workload, with an error of less than 5%. In addition, a small-target human key point recognition network was developed to analyze the image sequences captured by the camera. The knee joint angle and the knee joint pressure distribution during the sit-to-stand conversion process were mapped to a three-dimensional interactive platform to form a digital twin system. (3) Results: The system can effectively capture the biomechanical behavior of the knee joint during movement and shows high accuracy in joint angle tracking and structure simulation. (4) Conclusions: This study provides an accurate and comprehensive method for analyzing the biomechanical characteristics of the knee joint during the movement of the elderly, laying a solid foundation for clinical rehabilitation research and the design of assistive devices in the field of rehabilitation medicine. Full article
(This article belongs to the Section Artificial Intelligence)
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9 pages, 1777 KB  
Article
Patient-Derived Explants of Osteoarthritic Synovium as Ex Vivo Model for Preclinical Research
by Claudia D’Oria, Gilberto Cincinelli, Ramona Bason, Federica Pisati, Francesca Simoncello, Isabella Scotti, Laura Giudice, Ilaria Suardi, Paolo Ferrua, Chiara Fossati, Pietro Simone Randelli, Roberto Caporali, Massimiliano Pagani and Francesca Ingegnoli
Int. J. Mol. Sci. 2025, 26(14), 6665; https://doi.org/10.3390/ijms26146665 - 11 Jul 2025
Viewed by 342
Abstract
Osteoarthritis (OA) is the most common chronic arthropathy worldwide. OA synovitis is a common feature that predicts the development and progression of symptoms and joint damage. Although the OA synovium is a target for novel therapies, the development of ex vivo models remains [...] Read more.
Osteoarthritis (OA) is the most common chronic arthropathy worldwide. OA synovitis is a common feature that predicts the development and progression of symptoms and joint damage. Although the OA synovium is a target for novel therapies, the development of ex vivo models remains an area requiring further research. We aim to develop a 3D tissue explant culture model of human OA synovium that preserves the architecture and cellular heterogeneity of the original tissue in vitro. We derived tissue explant models from seven patients with OA and followed the culture for up to 10 days, assessing their morphology and cellular composition by immunohistochemistry (IHC) and flow cytometry, respectively. IHC analysis of explant cultures showed that tissue integrity and viability were maintained in our in vitro system. Furthermore, cellular heterogeneity was essentially unchanged when considering CD4+ T cells, CD8+ T cells, and myeloid fractions in our model. No significant variation was observed in the CD90+ and CD90-CD55+ fractions, which also maintained an activated state as indicated by high levels of FAP expression. An ex vivo OA synovial tissue explant model can maintain pathological tissue integrity for 10 days in culture. This simple and reliable culture system may be useful for analyzing the pathogenesis of OA disease and for the development and testing of therapeutic drugs. Full article
(This article belongs to the Special Issue Recent Advances in Osteoarthritis Pathways and Biomarker Research)
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40 pages, 2250 KB  
Review
Comprehensive Comparative Analysis of Lower Limb Exoskeleton Research: Control, Design, and Application
by Sk Hasan and Nafizul Alam
Actuators 2025, 14(7), 342; https://doi.org/10.3390/act14070342 - 9 Jul 2025
Viewed by 1247
Abstract
This review provides a comprehensive analysis of recent advancements in lower limb exoskeleton systems, focusing on applications, control strategies, hardware architecture, sensing modalities, human-robot interaction, evaluation methods, and technical innovations. The study spans systems developed for gait rehabilitation, mobility assistance, terrain adaptation, pediatric [...] Read more.
This review provides a comprehensive analysis of recent advancements in lower limb exoskeleton systems, focusing on applications, control strategies, hardware architecture, sensing modalities, human-robot interaction, evaluation methods, and technical innovations. The study spans systems developed for gait rehabilitation, mobility assistance, terrain adaptation, pediatric use, and industrial support. Applications range from sit-to-stand transitions and post-stroke therapy to balance support and real-world navigation. Control approaches vary from traditional impedance and fuzzy logic models to advanced data-driven frameworks, including reinforcement learning, recurrent neural networks, and digital twin-based optimization. These controllers support personalized and adaptive interaction, enabling real-time intent recognition, torque modulation, and gait phase synchronization across different users and tasks. Hardware platforms include powered multi-degree-of-freedom exoskeletons, passive assistive devices, compliant joint systems, and pediatric-specific configurations. Innovations in actuator design, modular architecture, and lightweight materials support increased usability and energy efficiency. Sensor systems integrate EMG, EEG, IMU, vision, and force feedback, supporting multimodal perception for motion prediction, terrain classification, and user monitoring. Human–robot interaction strategies emphasize safe, intuitive, and cooperative engagement. Controllers are increasingly user-specific, leveraging biosignals and gait metrics to tailor assistance. Evaluation methodologies include simulation, phantom testing, and human–subject trials across clinical and real-world environments, with performance measured through joint tracking accuracy, stability indices, and functional mobility scores. Overall, the review highlights the field’s evolution toward intelligent, adaptable, and user-centered systems, offering promising solutions for rehabilitation, mobility enhancement, and assistive autonomy in diverse populations. Following a detailed review of current developments, strategic recommendations are made to enhance and evolve existing exoskeleton technologies. Full article
(This article belongs to the Section Actuators for Robotics)
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24 pages, 1185 KB  
Review
A Comprehensive Review of Elbow Exoskeletons: Classification by Structure, Actuation, and Sensing Technologies
by Callista Shekar Ayu Supriyono, Mihai Dragusanu and Monica Malvezzi
Sensors 2025, 25(14), 4263; https://doi.org/10.3390/s25144263 - 9 Jul 2025
Viewed by 748
Abstract
The development of wearable robotic exoskeletons has seen rapid progress in recent years, driven by the growing need for technologies that support motor rehabilitation, assist individuals with physical impairments, and enhance human capabilities in both clinical and everyday contexts. Within this field, elbow [...] Read more.
The development of wearable robotic exoskeletons has seen rapid progress in recent years, driven by the growing need for technologies that support motor rehabilitation, assist individuals with physical impairments, and enhance human capabilities in both clinical and everyday contexts. Within this field, elbow exoskeletons have emerged as a key focus due to the joint’s essential role in upper limb functionality and its frequent impairment following neurological injuries such as stroke. With increasing research activity, there is a strong interest in evaluating these systems not only from a technical perspective but also in terms of user comfort, adaptability, and clinical relevance. This review investigates recent advancements in elbow exoskeleton technology, evaluating their effectiveness and identifying key design challenges and limitations. Devices are categorized based on three main criteria: mechanical structure (rigid, soft, or hybrid), actuation method, and sensing technologies. Additionally, the review classifies systems by their supported range of motion, flexion–extension, supination–pronation, or both. Through a systematic analysis of these features, the paper highlights current design trends, common trade-offs, and research gaps, aiming to guide the development of more practical, effective, and accessible elbow exoskeletons. Full article
(This article belongs to the Special Issue Sensors and Data Analysis for Biomechanics and Physical Activity)
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