The modified drawing test for assessment of arm movement quality

The cerebrovascular accident often results in motor impairment of one of the upper limbs, hence, compromising the quality of life of stroke survivors. Rehabilitation aims to restore the movement abilities of the paralyzed/paretic upper limb. An important element in rehabilitation is to apply a quantified measure of the quality of movement, in order to follow the recovery and select the most appropriate therapeutic modality. We developed a method that uses data recorded during planar movements and outputs an objective measure that relates to the smoothness, velocity and precision of the movement. This method is universal, in a sense that hand position can be recorded by any available means (e.g., robot assistant, digitizing board, motion tracking systems, etc). The method follows the Drawing Test, but generates results that show the ability of the patient to make point to point movements and track the presented trajectory. The method is based on measurements of hand position during movement along a target path in form of a 2 cm wide rectangle. The patient's task is to move the hand along the target path as quickly as possible, with as few contacts (collisions) with the sides of the path. This paper addresses the aspects of automatic detection of parameters that quantify the quality of movement (speed, smoothness and precision). The use of this method is presented with 10 patients

Razvoj numeričkih modela za efikasnu kakaterizaciju disperzivnih i generalnih anizotropnih elektromagnetskih struktura u mikrotalasnom opsegu frekvencija

In the dissertation, two methods for the realization and implementation of compact numerical models are presented using the TLM (Transmission Line Matrix) method based on Z-transformation techniques for the modeling of dispersive and general anisotropic electromagnetic structures in the microwave frequency range. The formulation of the Z-TLM method has been extended to cover the general case of a numerical network based on nonuniform spatial discretization. The first method was developed in response to the problem of modeling geometrically small, but from an electromagnetic viewpoint of important, dispersive and generally anisotropic electromagnetic structures, by using conventional methods based on the use of a fine resolution network, being highly demanding regarding computer resources. Within this method, the structure is modeled by the introduction of an appropriate interface between the neighboring TLM nodes that simulates the exchange of voltage impulses in the same way as the structure is present in the numerical network, which is convenient in cases where the direct behavior of the electromagnetic field within the structure is not important for analysis. This significantly reduces amount of required memory and processor resources, as well as the duration of the simulation, where the necessary number of nodes in the numerical network can be reduced for more than 90% in some cases. Second presented method provides the possibility that dispersive and generally anisotropic structures, characterized only by the scattering matrix, are introduced into a numerical simulation in order to analyze the effects of the propagation and distribution of the electromagnetic field within these structures. Modeling is done using the effective electromagnetic parameters calculated by applying the appropriate retrieval method to the scattering matrix coefficients of the modeled structure, which can be obtained by experimental measurement, analytical approach, or using one of the reliable methods of electromagnetic simulation. This method opens the possibility for a potential analysis of the effect of changing the effective parameters on the distribution of the electromagnetic field for optimization of the existing and development of new components and devices based on generally anisotropic and dispersive materials such as antennas and filters. The developed methods are implemented into a non-commercial solver using the higher-level programming language - MATLAB in order to numerically simulate dispersive and generally anisotropic materials in the time domain. The efficiency and reliability of both methods are verified and illustrated on examples of thin panels of carbon fiber composites, metamaterials and chiral material

MODIFIED INTERNAL MODEL CONTROL FOR A THERAPEUTIC ROBOT

We present the use of the modified internal model controller (MIMC) and the “Probability Tube” (PT) action representation for robot-assisted upper extremities training of hemiplegic patients. The robot-assisted training session has two phases. During the first "demonstration" phase the robot learns from the therapist the target path through examples. In the second "exercise" phase the robot assists a patient to follow the target path. During this process, the control limits the interface force between the robot and the hand to be below the preset threshold (F = 50 N). The system allows the assessment of the range of movement, the positional error between the target and the reached position, the amount of added assistance (the interface force between the hand and the robot). We demonstrate the operation in two hemiplegic patients. The patients and therapist suggested after the tests that the new system is straightforward and intuitive for clinical applications

Electrochemical synthesis and characterization of basic bismuth nitrate [Bi6O5(OH)3](NO3)5·2H2O: a potential highly efficient sorbent for textile reactive dye removal

A new method of synthesis was developed for the preparation of basic bismuth nitrate [Bi6O5(OH)3](NO3)5·2H2O (ECBBN). Electrochemical synthesis of the material was carried out by galvanostatic electrodeposition from an acidic Bi(III) solution on a Ti substrate and further thermal treatment in air at 200 °C. Characterization of ECBBN was conducted by employing SEM–EDX, N2 adsorption, XRD and FTIR, and its pI was also determined. The analyses showed that the material obtained was pure [Bi6O5(OH)3](NO3)5·2H2O. Morphologically, ECBBN aggregates were composed of crystals, some smaller than 50 nm. Electrochemically synthesized sorbent (ECBBN) was used for the removal of the textile dye Reactive Blue 19 (RB19) from deionized water and model solutions of polluted river water, and it showed considerably superior sorption performance compared to other inorganic sorbents synthesized by conventional methods reported in the literature. A kinetic study suggests that the sorption process is both under reaction and diffusion control. Equilibration of the sorption process was attained in several minutes, i.e. the sorption process is very fast. The sorption equilibrium data were well interpreted by the Langmuir, Redlich–Peterson and Brouers–Sotolongo isotherm. Using Langmuir isotherm, the maximum sorption capacity of ECBBN was reached at pH 2 and was 1049.19 mg g−1

Cognitive vision system for control of dexterous prosthetic hands: Experimental evaluation

<p>Abstract</p> <p>Background</p> <p>Dexterous prosthetic hands that were developed recently, such as SmartHand and i-LIMB, are highly sophisticated; they have individually controllable fingers and the thumb that is able to abduct/adduct. This flexibility allows implementation of many different grasping strategies, but also requires new control algorithms that can exploit the many degrees of freedom available. The current study presents and tests the operation of a new control method for dexterous prosthetic hands.</p> <p>Methods</p> <p>The central component of the proposed method is an autonomous controller comprising a vision system with rule-based reasoning mounted on a dexterous hand (CyberHand). The controller, termed cognitive vision system (CVS), mimics biological control and generates commands for prehension. The CVS was integrated into a hierarchical control structure: 1) the user triggers the system and controls the orientation of the hand; 2) a high-level controller automatically selects the grasp type and size; and 3) an embedded hand controller implements the selected grasp using closed-loop position/force control. The operation of the control system was tested in 13 healthy subjects who used Cyberhand, attached to the forearm, to grasp and transport 18 objects placed at two different distances.</p> <p>Results</p> <p>The system correctly estimated grasp type and size (nine commands in total) in about 84% of the trials. In an additional 6% of the trials, the grasp type and/or size were different from the optimal ones, but they were still good enough for the grasp to be successful. If the control task was simplified by decreasing the number of possible commands, the classification accuracy increased (e.g., 93% for guessing the grasp type only).</p> <p>Conclusions</p> <p>The original outcome of this research is a novel controller empowered by vision and reasoning and capable of high-level analysis (i.e., determining object properties) and autonomous decision making (i.e., selecting the grasp type and size). The automatic control eases the burden from the user and, as a result, the user can concentrate on what he/she does, not on how he/she should do it. The tests showed that the performance of the controller was satisfactory and that the users were able to operate the system with minimal prior training.</p

Razvoj numeričkih modela za efikasnu kakaterizaciju disperzivnih i generalnih anizotropnih elektromagnetskih struktura u mikrotalasnom opsegu frekvencija

In the dissertation, two methods for the realization and implementation of compact numerical models are presented using the TLM (Transmission Line Matrix) method based on Z-transformation techniques for the modeling of dispersive and general anisotropic electromagnetic structures in the microwave frequency range. The formulation of the Z-TLM method has been extended to cover the general case of a numerical network based on nonuniform spatial discretization. The first method was developed in response to the problem of modeling geometrically small, but from an electromagnetic viewpoint of important, dispersive and generally anisotropic electromagnetic structures, by using conventional methods based on the use of a fine resolution network, being highly demanding regarding computer resources. Within this method, the structure is modeled by the introduction of an appropriate interface between the neighboring TLM nodes that simulates the exchange of voltage impulses in the same way as the structure is present in the numerical network, which is convenient in cases where the direct behavior of the electromagnetic field within the structure is not important for analysis. This significantly reduces amount of required memory and processor resources, as well as the duration of the simulation, where the necessary number of nodes in the numerical network can be reduced for more than 90% in some cases. Second presented method provides the possibility that dispersive and generally anisotropic structures, characterized only by the scattering matrix, are introduced into a numerical simulation in order to analyze the effects of the propagation and distribution of the electromagnetic field within these structures. Modeling is done using the effective electromagnetic parameters calculated by applying the appropriate retrieval method to the scattering matrix coefficients of the modeled structure, which can be obtained by experimental measurement, analytical approach, or using one of the reliable methods of electromagnetic simulation. This method opens the possibility for a potential analysis of the effect of changing the effective parameters on the distribution of the electromagnetic field for optimization of the existing and development of new components and devices based on generally anisotropic and dispersive materials such as antennas and filters. The developed methods are implemented into a non-commercial solver using the higher-level programming language - MATLAB in order to numerically simulate dispersive and generally anisotropic materials in the time domain. The efficiency and reliability of both methods are verified and illustrated on examples of thin panels of carbon fiber composites, metamaterials and chiral material

Open loop control of the five-axis missile and target flight motion simulator implementation / Внедрение системы управления пятиосевых имитаторов полета ракеты и воздушной цели в разомкнутом цикле / Implementacija upravljanja petoosnim simulatorom leta rakete i cilja u otvorenoj petlji

An important phase in missile systems development is flight testing and simulation in the environmental conditions dictated by the operation the system is made for. Since field testing of complex systems means a big financial burden and a time consuming process, hardware in the loop (HIL) simulations represent a very effective solution for saving both costs and time. This paper presents an implementation of a control application that integrates synchronized data generation and acquisition on the five-axis missile and target flight motion simulator owned by the HIL laboratory. The described simulation application is a result of a missile development engineer's need for a simple way to acquire information on a real missile response, when desired control signals are provided. The solution is realized in Lab VIEW software using a robust software design architecture named 'classic state machine'. / Важнейшим фактором в развитии ракетных систем является этап моделирования и симуляции движения ракеты в соответствующих операционным параметрам условиях. Учитывая высокую стоимость полевых испытаний подобных систем, большие финансовые расходы и продолжительность подготовительных мероприятий, симулирование в рамках программно-аппаратного моделирования (Hardware in the loop - HIL) является наиболее эффективным испытательным решением. В данной статье описан процесс внедрения системы управления, то есть, синхронизированного генерирования и активации данных пятиосевого имитатора движения ракеты и воздушной цели, разработанного в лаборатории программно-аппаратного моделирования. Описанное в работе приложение имитатора обеспечивает эффективный контроль и безопасную среду, так как используя данную систему инженер-испытатель может сосредоточиться на функциональности устройства и быть уверенными в реальных параметрах движения ракеты. Решение разработано на платформе LabVIEW программного комплекса, с робастной архитектурой программного обеспечения, под названием «классический конечный автомат». / Razvoj raketnih sistema podrazumeva važne faze testiranja i simulacije leta rakete u uslovima okruženja koje diktira operacija za koju je sistem izrađen. Kako terenska ispitivanja ovako složenih sistema zahtevaju veliki utrošak finansijskih resursa, a i mnogo vremena, simulacije koje podrazumevaju hardver u petlji (Hardware in the loop - HIL) predstavljaju vrlo efikasno rešenje za smanjenje troškova razvoja i testiranja. U ovom radu predstavljena je implementacija upravljanja, odnosno sinhronizovanog generisanja i akvizicije podataka na petoosnom simulatoru leta rakete i cilja laboratorije za hardver u petlji (HIL laboratorije). Opisana aplikacija za simulaciju javila se kao rezultat potrebe inženjera razvoja raketa za jednostavnim načinom akviziranja informacja o odzivu realne rakete na željena i zadata upravljanja. Rešenje je realizovano u LabVIEW softverskom paketu primenom robusne arhitekture softvera, takozvane klasične mašine stanja

Feedback-Mediated Upper Extremities Exercise: Increasing Patient Motivation in Poststroke Rehabilitation

Purpose. This proof-of-concept study investigated whether feedback-mediated exercise (FME) of the affected arm of hemiplegic patients increases patient motivation and promotes greater improvement of motor function, compared to no-feedback exercise (NFE). Method. We developed a feedback-mediated treatment that uses gaming scenarios and allows online and offline monitoring of both temporal and spatial characteristics of planar movements. Twenty poststroke hemiplegic inpatients, randomly assigned to the FME and NFE group, received therapy five days a week for three weeks. The outcome measures were evaluated from the following: (1) the modified drawing test (mDT), (2) received therapy time—RTT, and (3) intrinsic motivation inventory—IMI. Results. The FME group patients showed significantly higher improvement in the speed metric (P<0.01), and smoothness metric (P<0.01), as well as higher RTT (P<0.01). Significantly higher patient motivation is observed in the FME group (interest/enjoyment subscale (P<0.01) and perceived competence subscale (P<0.01)). Conclusion. Prolonged endurance in training and greater improvement in certain areas of motor function, as well as very high patient motivation and strong positive impressions about the treatment, suggest the positive effects of feedback-mediated treatment and its high level of acceptance by patients

Application of new biosorbent based on chemicaly modified Lagenaria vulgaris shell for the removal of copper(II) from aqueous solutions: Effects of operational parameters

In present study a low cost biosorbent derived from Lagenaria vulgaris plant by xanthation, was tested for its ability to remove copper from aqueous solution. The effect of contact time, initial pH, initial concentration of copper(II) ions and adsorbent dosage on the removal efficiency were studied in a batch process mode. The optimal pH for investigated metal was 5. A dosage of 4 g dm-3 of xanthated Lagenaria vulgaris biosorbent (xLVB) was found to be effective for maximum uptake of copper(II). The kinetic of sorption of metal was fast, reaching at equilibrium in 50 min. The kinetic data were found to follow closely the pseudo-second-order model. The adsorption equilibrium was described well by the Langmuir isotherm model with maximum adsorption capacity of 23.18 mg g-1 copper(II) ions on xLVB. The presence of sulfur groups on xLVB were identified by FTIR spectroscopic study. Copper removal efficiency was achieved at 81.35% from copper plating industry wastevater