470 research outputs found

    Novel computational protocol to support transfemoral prosthetic alignment procedure using machine learning techniques

    Get PDF
    The prosthetic alignment procedure considers biomechanical, anatomical and comfort characteristics of the amputee to achieve an acceptable gait. Prosthetic malalignment induces long-term disease. The assessment of alignment is highly variable and subjective to the experience of the prosthetist, so the use of machine learning could assist the prosthetist during the judgment of optimal alignment.Peer ReviewedPostprint (published version

    Beam scanning by liquid-crystal biasing in a modified SIW structure

    Get PDF
    A fixed-frequency beam-scanning 1D antenna based on Liquid Crystals (LCs) is designed for application in 2D scanning with lateral alignment. The 2D array environment imposes full decoupling of adjacent 1D antennas, which often conflicts with the LC requirement of DC biasing: the proposed design accommodates both. The LC medium is placed inside a Substrate Integrated Waveguide (SIW) modified to work as a Groove Gap Waveguide, with radiating slots etched on the upper broad wall, that radiates as a Leaky-Wave Antenna (LWA). This allows effective application of the DC bias voltage needed for tuning the LCs. At the same time, the RF field remains laterally confined, enabling the possibility to lay several antennas in parallel and achieve 2D beam scanning. The design is validated by simulation employing the actual properties of a commercial LC medium

    What is the Impact of Below Ankle Amputation upon Quality of Life for Individuals with Type 2 Diabetes Mellitus?

    Get PDF
    The research question arose out of researcher observation of differing practices and patient experiences whilst employed concurrently in two NHS Trusts. The research sought to gain understanding of the impact of diabetes-related below ankle amputation upon quality of life. Twenty-eight semi-structured individual interviews were undertaken which explored the lived experiences of people who had a below ankle amputation and had been cared for by the same multidisciplinary foot care team. Interviews were analysed using template analysis, a form of thematic analysis which allowed for incorporation of a priori knowledge to contribute to the development of codes and themes. NVivo software was used to assist with the organisation of these findings. The original contribution to knowledge was identified following data analysis. The analysis revealed a variety of perspectives as to the impact of below ankle amputation upon quality of life. This related to an individual’s acceptance and adaptation to the amputation, regardless of the level of the amputation experienced. Adaptation, and therefore quality of life was impacted by lack of social support, and by difficulties gaining societal support such as social care and monetary support. A conceptual framework was developed to provide a precis of the new knowledge developed. The conceptual framework presented the interaction of factors impacting upon adaptation and factors subjectively perceived as important to quality of life. The research developed a suggested set of action points for clinicians working with these individuals, such as providing education upon the amputation journey and rehabilitation, establishing levels of support prior to amputation occurring to identify individuals who may require additional psychological or educational support. Further research was suggested to explore the development of measures which combined adaptation and quality of life to understand the impact of below ankle amputation more clearly for the individual. The author also suggested that the person completing the measure should be able to rank and add factors personally important for it to truly gain insight into individual quality of life

    Lower limb exoskeleton robot and its cooperative control: A review, trends, and challenges for future research

    Get PDF
    Effective control of an exoskeleton robot (ER) using a human-robot interface is crucial for assessing the robot's movements and the force they produce to generate efficient control signals. Interestingly, certain surveys were done to show off cutting-edge exoskeleton robots. The review papers that were previously published have not thoroughly examined the control strategy, which is a crucial component of automating exoskeleton systems. As a result, this review focuses on examining the most recent developments and problems associated with exoskeleton control systems, particularly during the last few years (2017–2022). In addition, the trends and challenges of cooperative control, particularly multi-information fusion, are discussed

    Evaluating EEG–EMG Fusion-Based Classification as a Method for Improving Control of Wearable Robotic Devices for Upper-Limb Rehabilitation

    Get PDF
    Musculoskeletal disorders are the biggest cause of disability worldwide, and wearable mechatronic rehabilitation devices have been proposed for treatment. However, before widespread adoption, improvements in user control and system adaptability are required. User intention should be detected intuitively, and user-induced changes in system dynamics should be unobtrusively identified and corrected. Developments often focus on model-dependent nonlinear control theory, which is challenging to implement for wearable devices. One alternative is to incorporate bioelectrical signal-based machine learning into the system, allowing for simpler controller designs to be augmented by supplemental brain (electroencephalography/EEG) and muscle (electromyography/EMG) information. To extract user intention better, sensor fusion techniques have been proposed to combine EEG and EMG; however, further development is required to enhance the capabilities of EEG–EMG fusion beyond basic motion classification. To this end, the goals of this thesis were to investigate expanded methods of EEG–EMG fusion and to develop a novel control system based on the incorporation of EEG–EMG fusion classifiers. A dataset of EEG and EMG signals were collected during dynamic elbow flexion–extension motions and used to develop EEG–EMG fusion models to classify task weight, as well as motion intention. A variety of fusion methods were investigated, such as a Weighted Average decision-level fusion (83.01 ± 6.04% accuracy) and Convolutional Neural Network-based input-level fusion (81.57 ± 7.11% accuracy), demonstrating that EEG–EMG fusion can classify more indirect tasks. A novel control system, referred to as a Task Weight Selective Controller (TWSC), was implemented using a Gain Scheduling-based approach, dictated by external load estimations from an EEG–EMG fusion classifier. To improve system stability, classifier prediction debouncing was also proposed to reduce misclassifications through filtering. Performance of the TWSC was evaluated using a developed upper-limb brace simulator. Due to simulator limitations, no significant difference in error was observed between the TWSC and PID control. However, results did demonstrate the feasibility of prediction debouncing, showing it provided smoother device motion. Continued development of the TWSC, and EEG–EMG fusion techniques will ultimately result in wearable devices that are able to adapt to changing loads more effectively, serving to improve the user experience during operation

    Computational approaches to Explainable Artificial Intelligence: Advances in theory, applications and trends

    Get PDF
    Deep Learning (DL), a groundbreaking branch of Machine Learning (ML), has emerged as a driving force in both theoretical and applied Artificial Intelligence (AI). DL algorithms, rooted in complex and non-linear artificial neural systems, excel at extracting high-level features from data. DL has demonstrated human-level performance in real-world tasks, including clinical diagnostics, and has unlocked solutions to previously intractable problems in virtual agent design, robotics, genomics, neuroimaging, computer vision, and industrial automation. In this paper, the most relevant advances from the last few years in Artificial Intelligence (AI) and several applications to neuroscience, neuroimaging, computer vision, and robotics are presented, reviewed and discussed. In this way, we summarize the state-of-the-art in AI methods, models and applications within a collection of works presented at the 9 International Conference on the Interplay between Natural and Artificial Computation (IWINAC). The works presented in this paper are excellent examples of new scientific discoveries made in laboratories that have successfully transitioned to real-life applications

    Advancing clinical evaluation and diagnostics with artificial intelligence technologies

    Get PDF
    Machine Learning (ML) is extensively used in diverse healthcare applications to aid physicians in diagnosing and identifying associations, sometimes hidden, between dif- ferent biomedical parameters. This PhD thesis investigates the interplay of medical images and biosignals to study the mechanisms of aging, knee cartilage degeneration, and Motion Sickness (MS). The first study shows the predictive power of soft tissue radiodensitometric parameters from mid-thigh CT scans. We used data from the AGES-Reykjavik study, correlating soft tissue numerical profiles from 3,000 subjects with cardiac pathophysiologies, hy- pertension, and diabetes. The results show the role of fat, muscle, and connective tissue in the evaluation of healthy aging. Moreover, we classify patients experiencing gait symptoms, neurological deficits, and a history of stroke in a Korean population, reveal- ing the significant impact of cognitive dual-gait analysis when coupled with single-gait. The second study establishes new paradigms for knee cartilage assessment, correlating 2D and 3D medical image features obtained from CT and MRI scans. In the frame of the EU-project RESTORE we were able to classify degenerative, traumatic, and healthy cartilages based on their bone and cartilage features, as well as we determine the basis for the development of a patient-specific cartilage profile. Finally, in the MS study, based on a virtual reality simulation synchronized with a moving platform and EEG, heart rate, and EMG, we extracted over 3,000 features and analyzed their importance in predicting MS symptoms, concussion in female ath- letes, and lifestyle influence. The MS features are extracted from the brain, muscle, heart, and from the movement of the center of pressure during the experiment and demonstrate their potential value to advance quantitative evaluation of postural con- trol response. This work demonstrates, through various studies, the importance of ML technologies in improving clinical evaluation and diagnosis contributing to advance our understanding of the mechanisms associated with pathological conditions.Tölvulærdómur (Machine Learning eða ML) er algjörlega viðurkennt og nýtt í ýmsum heilbrigðisþjónustuviðskiptum til að hjálpa læknunum við að greina og finna tengsl milli mismunandi líffærafræðilegra gilda, stundum dulinna. Þessi doktorsritgerð fjallar um samspil læknisfræðilegra mynda og lífsmerkja til að skoða eðli aldrunar, niðurbrot hnéhringjar og hreyfikerfissjúkdóms (Motion Sickness eða MS). Fyrsta rannsóknin sýnir spárkraft midjubeins-CT-skanna í því að fullyrða staðfest- ar meðalþyngdarlíkön, þar sem gögn úr AGES-Reykjavik-rannsókninni eru tengd við hjarta- og æðafræðilega sjúkdóma, blóðþrýstingsveikindi og sykursýki hjá 3.000 þátt- takendum. Niðurstöðurnar sýna hlutverk fitu, vöðva og tengikjarna í mati á heilbrigð- um öldrun. Þar að auki flokkum við sjúklinga sem upplifa gangvandamál, taugaein- kenni og sögu af heilablóðfalli í kóreanskri þjóð, þar sem einstök gangtaksskoðun er tengd saman við tvískoðun. Önnur rannsóknin setur upp ný tölfræðisfræðileg umhverfisviðmið til matar á hnéhringju með samhengi 2D og 3D mynda sem aflað er úr CT og MRI-skömmtum. Í rauninni höfum við getuð flokkað niðurbrots-, slys- og heilbrigðar hnéhringjur á grundvelli bein- og brjóskmerkja með raun að sækja niðurstöður í umfjöllun um sjúklingar eftir réttu einkasniði. Að lokum, í MS-rannsókninni, notum við myndræn tilraun samþættaða með hreyfan- legan grundvöll og EEG, hjartslátt, EMG þar sem yfir 3.000 aðgerðir eru útfránn og greindir til að átta sig á áhrifum MS, höfuðárás hjá konum sem eru íþróttamenn, lífs- stíl og fleira. Einkenni MS eru aflöguð úr heilanum, vöðvum, hjarta og frá hreyfingum þyngdupunktsins á meðan tilraunin stendur og sýna mög

    Proceedings XXIII Congresso SIAMOC 2023

    Get PDF
    Il congresso annuale della Società Italiana di Analisi del Movimento in Clinica (SIAMOC), giunto quest’anno alla sua ventitreesima edizione, approda nuovamente a Roma. Il congresso SIAMOC, come ogni anno, è l’occasione per tutti i professionisti che operano nell’ambito dell’analisi del movimento di incontrarsi, presentare i risultati delle proprie ricerche e rimanere aggiornati sulle più recenti innovazioni riguardanti le procedure e le tecnologie per l’analisi del movimento nella pratica clinica. Il congresso SIAMOC 2023 di Roma si propone l’obiettivo di fornire ulteriore impulso ad una già eccellente attività di ricerca italiana nel settore dell’analisi del movimento e di conferirle ulteriore respiro ed impatto internazionale. Oltre ai qualificanti temi tradizionali che riguardano la ricerca di base e applicata in ambito clinico e sportivo, il congresso SIAMOC 2023 intende approfondire ulteriori tematiche di particolare interesse scientifico e di impatto sulla società. Tra questi temi anche quello dell’inserimento lavorativo di persone affette da disabilità anche grazie alla diffusione esponenziale in ambito clinico-occupazionale delle tecnologie robotiche collaborative e quello della protesica innovativa a supporto delle persone con amputazione. Verrà infine affrontato il tema dei nuovi algoritmi di intelligenza artificiale per l’ottimizzazione della classificazione in tempo reale dei pattern motori nei vari campi di applicazione

    The effectiveness and cost-effectiveness of upper limb prostheses

    Get PDF
    The cost of upper limb prostheses related health care are rising. One reason may be the more frequent prescription of the expensive multi-grip myoelectric hand prostheses. However, signs of non-usage of the additional grip options of these hands are described. In these cases, a more simple prosthesis might also suit the users’ needs. Therefore, we investigated: 1. Factors that affect prosthesis choice and use A qualitative meta-synthesis, focus group and a nationwide survey in which 358 participants selected their top-10 most important items regarding prosthesis use were performed. Based on these results, a measurement tool, the PUF-ULP, was developed, which provides a single score that represents the match between the user and their prosthesis. 2. Cost-effectiveness of upper limb prosthesis A total of 242 upper limb prostheses users completed a quality of life questionnaire, the PUF-ULP, and a cost questionnaire. Results indicated that myoelectric prostheses, especially the multi-grip ones, are the most expensive compared to other prostheses types, while no differences in quality of life or user experiences were apparent. 3. Multi-grip versus standard myoelectric hands Fourteen multi-grip myoelectric hand prosthesis users performed multiple tests with both the multi-grip and standard myoelectric hand. Additionally, the users’ experiences of the multi-grip myoelectric hand prostheses were compared with these of 19 standard myoelectric hand prosthesis users using questionnaires. Results showed no relevant advantages of the multi-grip hand over the standard hand. 4. Development decision aidIn a systematic co-creation process a decision aid about hand prosthesis was developed and implemented nationwide

    The influence of graphical user interface on motion onset brain-computer interface performance and the effect of data augmentation on motor imagery brain-computer interface

    Get PDF
    Motor Imagery Brain Computer Interface (MI BCI) is one of the most frequently used BCI modalities, due to the versatility of its applications. However, it still has unresolved issues like time-consuming calibration, low information transfer rate, and inconsistent performance across individuals. Combining MI BCI with Motion Onset Visual Evoked Potential (mVEP) BCI in a hybrid structure may solve some of these problems. Combining MI BCI with more robust mVEP BCI, would increase the degrees of freedom thereby increasing the information transfer rate, and would also indirectly improve intrasubject consistency in performance by replacing some MI-based tasks with mVEP. Unfortunately, due to Covid -19 pandemic experimental research on hybrid BCI was not possible, therefore this thesis focuses on two BCI separately. Chapter 1 provides an overview of different BCIs modalities and the underlying neurophysiological principles, followed by the objectives of the thesis. The research contributions are also highlighted. Finally, the thesis outlines are presented at the end of this chapter. Chapter 2 presents a comprehensive state of the art to the thesis, drawing on a wide range of literature in relevant fields. Specifically, it delves into MI BCI, mVEP BCI, Deep Learning, Transfer Learning (TL), Data Augmentation (DA) and Generative Adversarial Networks (GANs). Chapter 3 investigates the effect of graphical elements, in online and offline experiments. In the offline experiment, graphical elements such as the color, size, position, and layout were explored. Replacing a default red moving bar with a green and blue bar, changing the background color from white to gray, and using smaller visual angles did not lead to statistically significant improvement in accuracy. However, the effect size of η2 (0.085) indicated a moderate effect for these changes of graphical factors. Similarly, no statistically significant difference was found for the two different layouts in online experiments. Overall, the mVEP BCI has achieved a classification accuracy of approximately 80%, and it is relatively impervious to changes in graphical interface parameters. This suggests that mVEP is a promising candidate for a hybrid BCI system combined with MI, that requires dynamic, versatile graphical design features. In Chapter 4, various DA methods are explored, including Segmentation and Recombination in Time Domain, Segmentation and Recombination in Time-Frequency Domain, and Spatial Analogy. These methods are evaluated based on three feature extraction approaches: Common Spatial Patterns, Time Domain Parameters (TDP), and Band Power. The evaluation was conducted using a validated BCI set, namely the BCI Competition IV dataset 2a, as well as a dataset obtained from our research group. The methods are effective when a small dataset of single subject are available. All three DA methods significantly affect the performance of the TDP feature extraction method. Chapter 5 explored the use of GANs for DA in combination with TL and cropped training strategies using ShallowFBCSP classifier. It also used the same validated dataset (BCI competition IV dataset 2a) as in Chapter 4. In contrast to DA method explored in Chapter 4, this DA is suitable for larger datasets and for generalizing training based on other people’s data. Applying GAN-based DA to the dataset resulted on average in a 2% improvement in average accuracy (from 68.2% to 70.7%). This study provides a novel method to enable MI GAN training with only 40 trials per participant with the rest 8 people’s data for TL, addressing the data insufficiency issue for GANs. The evaluation of generated artificial trials revealed the importance of inter-class differences in MI patterns, which can be easily identified by GANs. Overall the thesis addressed the main practical issues of both mVEP and MI BCI paving the way for their successful combination in future experiments
    • …
    corecore