| 1. |
- Antfolk, Christian, et al.
(författare)
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Exploring the conditions for PhD-students to develop abilities to independently formulate research questions
- 2015
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Rapport (populärvet., debatt m.m.)abstract
- Developing an ability to independently formulate research questions is an important goal in doctoral education. During a seminar in the “Docent course”, accredited by Genombrottet at Lund University, the authors behind this paper ended up in a discussion on the actual conditions for developing such ability. During the discussions, the authors, based on their own experiences, identified several conditions that could hamper the PhD-students’ abilities to develop the skills required to independently formulate research questions. Examples of such conditions were: involvement in projects where objectives and deliverables already were stated by a funder, a lack of discussions with supervisors early in the PhD-process, and/or a lack of proper training. The authors also discussed if working with a compilation thesis automatically lead to contrived overall research questions, which resulted primarily as an afterthought at a very late stage in the process.
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| 2. |
- Antfolk, Maria, et al.
(författare)
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A single inlet two-stage acoustophoresis chip enabling tumor cell enrichment from white blood cells
- 2015
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Ingår i: Lab on a Chip. - 1473-0189. ; 15:9, s. 2102-2109
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Tidskriftsartikel (refereegranskat)abstract
- Metastatic disease is responsible for most cancer deaths, and hematogenous spread through circulating tumor cells (CTC) is a prerequisite for tumor dissemination. CTCs may undergo epithelial–mesenchymal transition where many epithelial cell characteristics are lost. Therefore, CTC isolation systems relying on epithelial cell markers are at risk of losing important subpopulations of cells. Here, a simple acoustophoresis-based cell separation instrument is presented. Cells are uniquely separated while maintained in their initial suspending medium, thus eliminating the need for a secondary cell-free medium to hydrodynamically pre-position them before the separation. When characterizing the system using polystyrene particles, 99.6 ± 0.2% of 7 μm diameter particles were collected through one outlet while 98.8 ± 0.5% of 5 μm particles were recovered through a second outlet. Prostate cancer cells (DU145) spiked into blood were enriched from white blood cells at a sample flow rate of 100 μL min−1 providing 86.5 ± 6.7% recovery of the cancer cells with 1.1 ± 0.2% contamination of white blood cells. By increasing the acoustic intensity a recovery of 94.8 ± 2.8% of cancer cells was achieved with 2.2 ± 0.6% contamination of white blood cells. The single inlet approach makes this instrument insensitive to acoustic impedance mismatch; a phenomenon reported to importantly affect accuracy in multi-laminar flow stream acoustophoresis. It also offers a possibility of concentrating the recovered cells in the chip, as opposed to systems relying on hydrodynamic pre-positioning which commonly dilute the target cells.
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| 3. |
- Huang, Huaiqi, et al.
(författare)
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Automatic hand phantom map detection methods
- 2015
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Ingår i: IEEE Biomedical Circuits and Systems Conference: Engineering for Healthy Minds and Able Bodies, BioCAS 2015 - Proceedings. - 9781479972333
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Konferensbidrag (refereegranskat)abstract
- Many amputees have maps of referred sensation from their missing hand on their residual limb (phantom maps). This skin area can serve as a target for providing amputees with tactile sensory feedback. Providing tactile feedback on the phantom map can improve the object manipulation ability, enhance embodiment of myoelectric prostheses users and help reduce phantom limb pain. The distribution of the phantom map varies with the individual. Here, we investigate a fast and accurate method for hand phantom map shape detection. We present three elementary (group testing, adaptive edge finding and support vector machines (SVM)) and two combined methods (SVM with majority-pooling and SVM with active learning) tested with different types of phantom map models and compare the classification error rates. The results show that SVM with majority-pooling has the smallest classification error rate.
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| 4. |
- Huang, Huaiqi, et al.
(författare)
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Automatic hand phantom map generation and detection using decomposition support vector machines
- 2018
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Ingår i: BioMedical Engineering Online. - : Springer Science and Business Media LLC. - 1475-925X. ; 17:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: There is a need for providing sensory feedback for myoelectric prosthesis users. Providing tactile feedback can improve object manipulation abilities, enhance the perceptual embodiment of myoelectric prostheses and help reduce phantom limb pain. Many amputees have referred sensation from their missing hand on their residual limbs (phantom maps). This skin area can serve as a target for providing amputees with non-invasive tactile sensory feedback. One of the challenges of providing sensory feedback on the phantom map is to define the accurate boundary of each phantom digit because the phantom map distribution varies from person to person. Methods: In this paper, automatic phantom map detection methods based on four decomposition support vector machine algorithms and three sampling methods are proposed, complemented by fuzzy logic and active learning strategies. The algorithms and methods are tested on two databases: the first one includes 400 generated phantom maps, whereby the phantom map generation algorithm was based on our observation of the phantom maps to ensure smooth phantom digit edges, variety, and representativeness. The second database includes five reported phantom map images and transformations thereof. The accuracy and training/ classification time of each algorithm using a dense stimulation array (with 100 $$\times $$ × 100 actuators) and two coarse stimulation arrays (with 3 $$\times $$ × 5 and 4 $$\times $$ × 6 actuators) are presented and compared. Results: Both generated and reported phantom map images share the same trends. Majority-pooling sampling effectively increases the training size, albeit introducing some noise, and thus produces the smallest error rates among the three proposed sampling methods. For different decomposition architectures, one-vs-one reduces unclassified regions and in general has higher classification accuracy than the other architectures. By introducing fuzzy logic to bias the penalty parameter, the influence of pooling-induced noise is reduced. Moreover, active learning with different strategies was also tested and shown to improve the accuracy by introducing more representative training samples. Overall, dense arrays employing one-vs-one fuzzy support vector machines with majority-pooling sampling have the smallest average absolute error rate (8.78% for generated phantom maps and 11.5% for reported and transformed phantom map images). The detection accuracy of coarse arrays was found to be significantly lower than for dense array. Conclusions: The results demonstrate the effectiveness of support vector machines using a dense array in detecting refined phantom map shapes, whereas coarse arrays are unsuitable for this task. We therefore propose a two-step approach, using first a non-wearable dense array to detect an accurate phantom map shape, then to apply a wearable coarse stimulation array customized according to the detection results. The proposed methodology can be used as a tool for helping haptic feedback designers and for tracking the evolvement of phantom maps.
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| 5. |
- Huang, Huaiqi, et al.
(författare)
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EMG pattern recognition using decomposition techniques for constructing multiclass classifiers
- 2016
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Ingår i: 2016 6th IEEE International Conference on Biomedical Robotics and Biomechatronics, BioRob 2016. - 9781509032877 ; , s. 1296-1301
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Konferensbidrag (refereegranskat)abstract
- To improve the dexterity of multi-functional myoelectric prosthetic hand, more accurate hand gesture recognition based on surface electromyographic (sEMG) signal is needed. This paper evaluates two types of time-domain EMG features, one independent feature and one combined feature including four features. The selected features from eight subjects with 13 finger movements were tested with four decomposed multi-class support vector machines (SVM), four decomposed linear discriminant analyses (LDA) and a multi-class LDA. The classification accuracy, training, and classification time are compared. The results have shown that the combined features decrease error rate, and binary tree based decomposition multiclass classifiers yield the highest classification success rate (88.2%) with relatively low training and classification time.
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| 6. |
- Huang, Huaiqi, et al.
(författare)
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Experiment and investigation of two types of vibrotactile devices
- 2016
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Ingår i: 2016 6th IEEE International Conference on Biomedical Robotics and Biomechatronics, BioRob 2016. - 9781509032884 - 9781509032877 ; , s. 1266-1271
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Konferensbidrag (refereegranskat)abstract
- Tactile displays have a wide range of applications in assistive technology, prosthetics, and rehabilitation. Vibrotactile stimulation shows potential to be integrated into wearable devices because of its small size, low power consumption, and relative fast responding speed. In this paper, experiments investigating vibrotactile minimal detectable level, just noticeable difference, and two point discrimination distance using eccentric rotating mass (ERM) and linear resonant actuator (LRA) are described and the results were analyzed. LRAs have shown potential to transmit binary information, while ERMs are more suitable for conveying more complexed signals. For both LRAs and ERMs, it is difficult to for subjects to correctly distinguish two points within 45 mm.
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| 7. |
- Huang, Huaiqi, et al.
(författare)
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Multi-modal sensory feedback system for upper limb amputees
- 2017
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Ingår i: Proceedings - 2017 1st New Generation of CAS, NGCAS 2017. - 9781509064472 ; , s. 193-196
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Konferensbidrag (refereegranskat)abstract
- Providing sensory feedback for myoelectric prosthetic users can not only increase the manipulation ability but can also introduce a feeling of embodiment. Previous research has demonstrated the feasibility of providing mechanotactile or vibrotactile feedback on the remaining stumps of amputees. To improve the recognition rate and reduce mental work load when identifying stimulation patterns, we propose a multi-modal sensory feedback system for upper limb amputees. The system consists of five tactile sensors, Bluetooth wireless communication modules, and a custom-designed multi-modal stimulation array incorporating vibrotactile and mechanotactile stimulation modalities. Three amputees (two with phantom map and one without phantom map) tested the system in localization and stimulation intensity identification tasks. Experimental results show the effectiveness of the multi-modal stimulation compared with single modal stimulation. To the best of our knowledge, this is the first attempt to combine vibrotactile and mechanotactile stimulation in a sensory feedback system for upper limb amputees.
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| 8. |
- Malešević, Nebojša, et al.
(författare)
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Decoding of individual finger movements from surface EMG signals using vector autoregressive hierarchical hidden Markov models (VARHHMM)
- 2017
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Ingår i: 2017 International Conference on Rehabilitation Robotics, ICORR 2017. - 9781538622964 ; , s. 1518-1523
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Konferensbidrag (refereegranskat)abstract
- In this paper we present a novel method for predicting individual fingers movements from surface electromyography (EMG). The method is intended for real-time dexterous control of a multifunctional prosthetic hand device. The EMG data was recorded using 16 single-ended channels positioned on the forearm of healthy participants. Synchronously with the EMG recording, the subjects performed consecutive finger movements based on the visual cues. Our algorithm could be described in following steps: extracting mean average value (MAV) of the EMG to be used as the feature for classification, piece-wise linear modeling of EMG feature dynamics, implementation of hierarchical hidden Markov models (HHMM) to capture transitions between linear models, and implementation of Bayesian inference as the classifier. The performance of our classifier was evaluated against commonly used real-time classifiers. The results show that the current algorithm setup classifies EMG data similarly to the best among tested classifiers but with equal or less computational complexity.
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| 9. |
- Malešević, Nebojša, et al.
(författare)
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Instrumented platform for assessment of isometric hand muscles contractions
- 2019
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Ingår i: Measurement Science and Technology. - : IOP Publishing. - 0957-0233 .- 1361-6501. ; 30:6
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Tidskriftsartikel (refereegranskat)abstract
- Measurement of forces exerted by a human hand while performing common gestures is a highly valuable task for assessment of neurorehabilitation and neurological disorders, but also, for control of movement that could be directly transferred to assistive devices. Even though accurate and selective multi-joint measurement of hand forces is desirable in both clinical and research applications there is no commercially available device able to perform such measurements. Moreover, the custom-made systems used in research commonly impose limitations, such as availability of only single, predefined hand aperture. Furthermore, there is no consensus on design requirements for custom made measurement systems that would enable comparison of results obtained during research or clinical hand function studies. In an attempt to provide a possible solution for a device capable of multi-joint hand forces measurement and disseminate it to the research community, this paper presents the mechanical and electronic design of an instrumented platform for assessment of isometric hand muscles contractions. Some of the key features related to the developed system are: flexibility in placing the hand/fingers, fast and easy hand fitting, adjustability to different lengths, circumferences and postures of the digits, and the possibility to register individual bidirectional forces from the digits and the wrist. The accuracy of isometric force measurements was evaluated in a controlled test with the reference high accuracy force gauge device during which the developed system showed high linearity (R 2 = 0.9999). As the more realistic test, the device was evaluated when force was applied to individual sensors but also during the intramuscular electromyography (iEMG) study. The data gathered during the iEMG measurements was thoroughly assessed to obtain three appropriate metrics; the first estimating crosstalk between individual force sensors; the second evaluating agreement between measured forces and forces estimated through iEMG; and the third providing qualitative evaluation of hand force in respect to activations of individual muscle units. The results of these analyses performed on multiple joint forces show agreement with previously published results, but with the difference that in that case, the measurement was performed with a single degree of freedom device.
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| 10. |
- Malešević, Nebojša, et al.
(författare)
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Vector Autoregressive Hierarchical Hidden Markov Models for Extracting Finger Movements Using Multichannel Surface EMG Signals
- 2018
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Ingår i: Complexity. - : Hindawi Limited. - 1076-2787 .- 1099-0526. ; 2018
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Tidskriftsartikel (refereegranskat)abstract
- We present a novel computational technique intended for the robust and adaptable control of a multifunctional prosthetic hand using multichannel surface electromyography. The initial processing of the input data was oriented towards extracting relevant time domain features of the EMG signal. Following the feature calculation, a piecewise modeling of the multidimensional EMG feature dynamics using vector autoregressive models was performed. The next step included the implementation of hierarchical hidden semi-Markov models to capture transitions between piecewise segments of movements and between different movements. Lastly, inversion of the model using an approximate Bayesian inference scheme served as the classifier. The effectiveness of the novel algorithms was assessed versus methods commonly used for real-time classification of EMGs in a prosthesis control application. The obtained results show that using hidden semi-Markov models as the top layer, instead of the hidden Markov models, ranks top in all the relevant metrics among the tested combinations. The choice of the presented methodology for the control of prosthetic hand is also supported by the equal or lower computational complexity required, compared to other algorithms, which enables the implementation on low-power microcontrollers, and the ability to adapt to user preferences of executing individual movements during activities of daily living.
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| 11. |
- Abbaspour, Sara, 1984-
(författare)
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Electromyogram Signal Enhancement and Upper-Limb Myoelectric Pattern Recognition
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Losing a limb causes difficulties in our daily life. To regain the ability to live an independent life, artificial limbs have been developed. Hand prostheses belong to a group of artificial limbs that can be controlled by the user through the activity of the remnant muscles above the amputation. Electromyogram (EMG) is one of the sources that can be used for control methods for hand prostheses. Surface EMGs are powerful, non-invasive tools that provide information about neuromuscular activity of the subjected muscle, which has been essential to its use as a source of control for prosthetic limbs. However, the complexity of this signal introduces a big challenge to its applications. EMG pattern recognition to decode different limb movements is an important advancement regarding the control of powered prostheses. It has the potential to enable the control of powered prostheses using the generated EMG by muscular contractions as an input. However, its use has yet to be transitioned into wide clinical use. Different algorithms have been developed in state of the art to decode different movements; however, the challenge still lies in different stages of a successful hand gesture recognition and improvements in these areas could potentially increase the functionality of powered prostheses. This thesis firstly focuses on improving the EMG signal’s quality by proposing novel and advanced filtering techniques. Four efficient approaches (adaptive neuro-fuzzy inference system-wavelet, artificial neural network-wavelet, adaptive subtraction and automated independent component analysis-wavelet) are proposed to improve the filtering process of surface EMG signals and effectively eliminate ECG interferences. Then, the offline performance of different EMG-based recognition algorithms for classifying different hand movements are evaluated with the aim of obtaining new myoelectric control configurations that improves the recognition stage. Afterwards, to gain proper insight on the implementation of myoelectric pattern recognition, a wide range of myoelectric pattern recognition algorithms are investigated in real time. The experimental result on 15 healthy volunteers suggests that linear discriminant analysis (LDA) and maximum likelihood estimation (MLE) outperform other classifiers. The real-time investigation illustrates that in addition to the LDA and MLE, multilayer perceptron also outperforms the other algorithms when compared using classification accuracy and completion rate.
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| 12. |
- Alriksson-Schmidt, Ann, et al.
(författare)
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Improving the Health of Individuals With Cerebral Palsy: Protocol for the Multidisciplinary Research Program MOVING ON WITH CP
- 2019
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Ingår i: Jmir Research Protocols. - Toronto, Canada : JMIR Publications Inc.. - 1929-0748. ; 8:10
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Tidskriftsartikel (refereegranskat)abstract
- Background: Cerebral palsy (CP) is one of the most common early onset disabilities globally. The causative brain damage in CP is nonprogressive, yet secondary conditions develop and worsen over time. Individuals with CP in Sweden and most of the Nordic countries are systematically followed in the national registry and follow-up program entitled the Cerebral Palsy Follow-Up Program (CPUP). CPUP has improved certain aspects of health care for individuals with CP and strengthened collaboration among professionals. However, there are still issues to resolve regarding health care for this specific population. Objective: The overall objectives of the research program MOVING ON WITH CP are to (1) improve the health care processes and delivery models; (2) develop, implement, and evaluate real-life solutions for Swedish health care provision; and (3) evaluate existing health care and social insurance benefit programs and processes in the context of CP. Methods: MOVING ON WITH CP comprises 9 projects within 3 themes. Evaluation of Existing Health Care (Theme A) consists of registry studies where data from CPUP will be merged with national official health databases, complemented by survey and interview data. In Equality in Health Care and Social Insurance (Theme B), mixed methods studies and registry studies will be complemented with focus group interviews to inform the development of new processes to apply for benefits. In New Solutions and Processes in Health Care Provision (Theme C), an eHealth (electronic health) procedure will be developed and tested to facilitate access to specialized health care, and equipment that improves the assessment of movement activity in individuals with CP will be developed. Results: The individual projects are currently being planned and will begin shortly. Feedback from users has been integrated. Ethics board approvals have been obtained. Conclusions: In this 6-year multidisciplinary program, professionals from the fields of medicine, social sciences, health sciences, and engineering, in collaboration with individuals with CP and their families, will evaluate existing health care, create conditions for a more equal health care, and develop new technologies to improve the health care management of people with CP.
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| 13. |
- Björkman, Anders, et al.
(författare)
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Sensory qualities of the phantom hand map in the residual forearm of amputees
- 2016
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Ingår i: Journal of Rehabilitation Medicine. - : Medical Journals Sweden AB. - 1651-2081 .- 1650-1977. ; 48:4, s. 70-365
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Most amputees experience referred sensations, known as a phantom hand map, on the residual forearm, where touch on specific areas is perceived as touch on the amputated hand. The aim of this study was to evaluate the sensory qualities of the phantom hand map.METHODS: In 10 traumatic forearm-amputees touch thres-holds and discriminative touch of the phantom hand map were assessed and compared with corresponding areas on the contralateral forearm. The study assessed the localization of touch on the phantom hand map, and how distinct and similar to normal touch the referred feeling was.RESULTS: Similar touch thresholds were seen in the phantom hand map and the control site. Tactile discrimination, requiring both detection of stimulus and interpretation, was significantly better in the phantom hand map.CONCLUSION: This explorative study suggests that the phantom hand map and the superior tactile discrimination seen in the phantom hand map are based on adaptations within the brain. Further studies investigating the neural basis for the phantom hand map are needed.
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| 14. |
- Li, Tao, et al.
(författare)
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Tactile display on the remaining hand for unilateral hand amputees
- 2016
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Ingår i: Current Directions in Biomedical Engineering. - : Walter de Gruyter GmbH. - 2364-5504. ; 2:1, s. 399-403
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Tidskriftsartikel (refereegranskat)abstract
- Human rely profoundly on tactile feedback from fingertips to interact with the environment, whereas most hand prostheses used in clinics provide no tactile feedback. In this study we demonstrate the feasibility to use a tactile display glove that can be worn by a unilateral hand amputee on the remaining healthy hand to display tactile feedback from a hand prosthesis. The main benefit is that users could easily distinguish the feedback for each finger, even without training. The claimed advantage is supported by preliminary tests with healthy subjects. This approach may lead to the development of effective and affordable tactile display devices that provide tactile feedback for individual fingertip of hand prostheses.
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| 15. |
- Moshontz, Hannah, et al.
(författare)
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The Psychological Science Accelerator: Advancing Psychology Through a Distributed Collaborative Network
- 2018
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Ingår i: Advances in Methods and Practices in Psychological Science. - : SAGE Publications. - 2515-2459 .- 2515-2467. ; 1:4, s. 501-515
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Tidskriftsartikel (refereegranskat)abstract
- Concerns about the veracity of psychological research have been growing. Many findings in psychological science are based on studies with insufficient statistical power and nonrepresentative samples, or may otherwise be limited to specific, ungeneralizable settings or populations. Crowdsourced research, a type of large-scale collaboration in which one or more research projects are conducted across multiple lab sites, offers a pragmatic solution to these and other current methodological challenges. The Psychological Science Accelerator (PSA) is a distributed network of laboratories designed to enable and support crowdsourced research projects. These projects can focus on novel research questions or replicate prior research in large, diverse samples. The PSA’s mission is to accelerate the accumulation of reliable and generalizable evidence in psychological science. Here, we describe the background, structure, principles, procedures, benefits, and challenges of the PSA. In contrast to other crowdsourced research networks, the PSA is ongoing (as opposed to time limited), efficient (in that structures and principles are reused for different projects), decentralized, diverse (in both subjects and researchers), and inclusive (of proposals, contributions, and other relevant input from anyone inside or outside the network). The PSA and other approaches to crowdsourced psychological science will advance understanding of mental processes and behaviors by enabling rigorous research and systematic examination of its generalizability.
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| 16. |
- Olsson, Alexander E., et al.
(författare)
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Extraction of Multi-Labelled Movement Information from the Raw HD-sEMG Image with Time-Domain Depth
- 2019
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 9:1
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Tidskriftsartikel (refereegranskat)abstract
- In contemporary muscle-computer interfaces for upper limb prosthetics there is often a trade-off between control robustness and range of executable movements. As a very low movement error rate is necessary in practical applications, this often results in a quite severe limitation of controllability; a problem growing ever more salient as the mechanical sophistication of multifunctional myoelectric prostheses continues to improve. A possible remedy for this could come from the use of multi-label machine learning methods, where complex movements can be expressed as the superposition of several simpler movements. Here, we investigate this claim by applying a multi-labeled classification scheme in the form of a deep convolutional neural network (CNN) to high density surface electromyography (HD-sEMG) recordings. We use 16 independent labels to model the movements of the hand and forearm state, representing its major degrees of freedom. By training the neural network on 16 × 8 sEMG image sequences 24 samples long with a sampling rate of 2048 Hz to detect these labels, we achieved a mean exact match rate of 78.7% and a mean Hamming loss of 2.9% across 14 healthy test subjects. With this, we demonstrate the feasibility of highly versatile and responsive sEMG control interfaces without loss of accuracy.
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| 17. |
- Olsson, Alexander, et al.
(författare)
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Exploiting the Intertemporal Structure of the Upper-Limb sEMG: Comparisons between an LSTM Network and Cross-Sectional Myoelectric Pattern Recognition Methods
- 2019
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Ingår i: 2019 41st Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). - 9781538613122 - 9781538613122
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Konferensbidrag (refereegranskat)abstract
- The use of natural myoelectric interfaces promises great value for a variety of potential applications, clinical and otherwise, provided a computational mapping between measured neuromuscular activity and executed motion can be approximated to a satisfactory degree. However, prevalent methods intended for such decoding of movement intent from the surface electromyogram (sEMG) based on pattern recognition typically do not capitalize on the inherently time series-like nature of the acquired signals. In this paper, we present the results from a comparative study in which the performances of traditional cross-sectional pattern recognition methods were compared with that of a classifier built on the natural assumption of temporal ordering by utilizing a long short-term memory (LSTM) neural network. The resulting evaluation indicate that the LSTM approach outperforms traditional gesture recognition techniques which are based on cross-sectional inference. These findings held both when the LSTM classifier operated on conventional features and on raw sEMG and for both healthy subjects and transradial amputees.
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| 18. |
- Svensson, Pamela, et al.
(författare)
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A review of invasive and non-invasive sensory feedback in upper limb prostheses
- 2017
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Ingår i: Expert Review of Medical Devices. - : Informa UK Limited. - 1743-4440 .- 1745-2422. ; 14:6, s. 439-447
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Forskningsöversikt (refereegranskat)abstract
- Introduction: The constant challenge to restore sensory feedback in prosthetic hands has provided several research solutions, but virtually none has reached clinical fruition. A prosthetic hand with sensory feedback that closely imitates an intact hand and provides a natural feeling may induce the prosthetic hand to be included in the body image and also reinforces the control of the prosthesis. Areas covered: This review presents non-invasive sensory feedback systems such as mechanotactile, vibrotactile, electrotactile and combinational systems which combine the modalities; multi-haptic feedback. Invasive sensory feedback has been tried less, because of the inherent risk, but it has successfully shown to restore some afferent channels. In this review, invasive methods are also discussed, both extraneural and intraneural electrodes, such as cuff electrodes and transverse intrafascicular multichannel electrodes. The focus of the review is on non-invasive methods of providing sensory feedback to upper-limb amputees. Expert commentary: Invoking embodiment has shown to be of importance for the control of prosthesis and acceptance by the prosthetic wearers. It is a challenge to provide conscious feedback to cover the lost sensibility of a hand, not be overwhelming and confusing for the user, and to integrate technology within the constraint of a wearable prosthesis.
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| 19. |
- Wijk, Ulrika, et al.
(författare)
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Touch on predefined areas on the forearm can be associated with specific fingers : Towards a new principle for sensory feedback in hand prostheses
- 2019
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Ingår i: Journal of Rehabilitation Medicine. - : Medical Journals Sweden AB. - 1651-2081 .- 1650-1977. ; 51:3, s. 209-216
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Currently available hand prostheses lack sensory feedback. A "phantom hand map", a referred sensation, on the skin of the residual arm is a possible target to provide amputees with non-invasive somatotopically matched sensory feedback. How-ever, not all amputees experience a phantom hand map. The aim of this study was to explore whether touch on predefined areas on the forearm can be associated with specific fingers.DESIGN: A longitudinal cohort study.SUBJECTS: A total of 31 able-bodied individuals.METHODS: A "tactile display" was developed consisting of 5 servo motors, which provided the user with mechanotactile stimulus. Predefined pressure points on the volar aspect of the forearm were stimulated during a 2-week structured training period.RESULTS: Agreement between the stimulated areas and the subjects' ability to discriminate the stimulation was high, with a distinct improvement up to the third training occasion, after which the kappa score stabilized for the rest of the period.CONCLUSION: It is possible to associate touch on intact skin on the forearm with specific fingers after a structured training period, and the effect persisted after 2 weeks. These results may be of importance for the development of non-invasive sensory feedback systems in hand prostheses.
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