Abstract: Robotics provides answers to amputees. The most
expensive solutions surgically connect the prosthesis to nerve endings.
There are also several types of non-invasive technologies that recover
nerve messages passing through the muscles. After analyzing these
messages, myoelectric prostheses perform the desired movement.
The main goal is to avoid all surgeries, which can be heavy and offer
cheaper alternatives. For an amputee, we use valid muscles to recover
the electrical signal involved in a muscle movement. EMG sensors
placed on the muscle allows us to measure a potential difference,
which our program transforms into control for a robotic arm with two
degrees of freedom. We have shown the feasibility of non-invasive
prostheses with two degrees of freedom. Signal analysis and an
increase in degrees of freedom is still being improved.
Abstract: Kinematic data wisely correlate vector quantities in
space to scalar parameters in time to assess the degree of symmetry
between the intact limb and the amputated limb with respect to a
normal model derived from the gait of control group participants.
Furthermore, these particular data allow a doctor to preliminarily
evaluate the usefulness of a certain rehabilitation therapy.
Kinetic curves allow the analysis of ground reaction forces (GRFs)
to assess the appropriateness of human motion.
Electromyography (EMG) allows the analysis of the fundamental
lower limb force contributions to quantify the level of gait
asymmetry. However, the use of this technological tool is expensive
and requires patient’s hospitalization. This research work suggests
overcoming the above limitations by applying artificial neural
networks.
Abstract: Hand grip strength has been utilized as an indicator to evaluate the motor ability of hands, responsible for performing multiple body functions. It is, however, difficult to evaluate other factors (other than hand muscular strength) utilizing the hand grip strength only. In this study, we analyzed the motor ability of hands using EMG and the hand grip strength, simultaneously in order to evaluate concentration, muscular strength reaction time, instantaneous muscular strength change, and agility in response to visual reaction. In results, the average time (and their standard deviations) of muscular strength reaction EMG signal and hand grip strength was found to be 209.6 ± 56.2 ms and 354.3 ± 54.6 ms, respectively. In addition, the onset time which represents acceleration time to reach 90% of maximum hand grip strength, was 382.9 ± 129.9 ms.
Abstract: Background: Occupational standing is associated with low back pain (LBP) development. Yet, trunk and gluteus-medius muscles’ fatigability has not been extensively studied during occupational standing. This study examined and correlated the rectus abdominus (RA), erector-spinae (ES), external oblique (EO), and gluteus-medius (GM) muscles’ fatigability on both sides while standing in a confined area for 30min Methods: Median frequency EMG data were collected from 15 female clinical instructors with chronic LBP (group A) and 15 asymptomatic controls (group B) (mean age 29.53±2.4 vs 29.07±2.4years, weight 63.6±7 vs 60±7.8kg, and height 162.73±4 vs 162.8±6cm respectively) using a spectrum analysis program. Data were collected in the first and last 5min of the standing task. Results: Using Mixed three-way ANOVA, group A showed significantly (p
Abstract: The development of an low cost acquisition system of S-EMG signals which are reliable, comfortable for the user and with high mobility shows to be a relevant proposition in modern biomedical engineering scenario. In the study, the sampling capacity of the Arduino microcontroller Atmel Atmega328 with an A / D converter with 10-bit resolution and its reconstructing capability of a signal of surface electromyography is analyzed. An electronic circuit to capture the signal through two differential channels was designed, signals from Biceps Brachialis of a healthy man of 21 years was acquired to test the system prototype. ARV, MDF, MNF and RMS estimators were used to compare de acquired signals with physiological values. The Arduino was configured with a sampling frequency of 1.5kHz for each channel, and the tests with the circuit designed offered a SNR of 20.57dB.
Abstract: This paper proposes a method of remotely controlling robots with arm gestures using surface electromyography (EMG) and accelerometer sensors attached to the operator’s wrists. The EMG and accelerometer sensors receive signals from the arm gestures of the operator and infer the corresponding movements to execute the command to control the robot. The movements of the robot include moving forward and backward and turning left and right. The accuracy is over 99% and movements can be controlled in real time.
Abstract: According to previous studies, some muscles present a non-homogeneous spatial distribution of its muscle fiber types and motor unit types. However, available muscle models only deal with muscles with homogeneous distributions. In this paper, a new architecture muscle model is proposed to permit the construction of non-uniform distributions of muscle fibers within the muscle cross section. The idea behind is the use of a motor unit placement algorithm that controls the spatial overlapping of the motor unit territories of each motor unit type. Results show the capabilities of the new algorithm to reproduce arbitrary muscle fiber type distributions.
Abstract: carrot is one of the important root vegetable crops,
and it is highly nutritious as it contains appreciable amount of
vitamins, minerals and β-carotene. The major objective of current
research was to evaluate the chemical composition of carrot variety
'Nante' hybrids in general and to select the best samples for fresh-cut
salad production. The research was accomplished on fresh in Latvia
cultivated carrots harvested in Zemgale region in the first part of
October, 2011 and immediately used for experiments. Late-bearing
variety 'Nante' hybrid carrots were used for analysis:
'Nante/Berlikum', 'Nante/Maestro', 'Nante/Forto', 'Nante/Bolero'
and 'Nante/Champion'. The quality parameters as moisture, soluble
solid, firmness, b-carotene, carotenoid, color, polyphenols, total
phenolic compounds and total antioxidant capacity were analyzed
using standard methods. For fresh-cut salad production as more
applicable could be recommended hybrids 'Nante/Forto' and
'Nante/Berlikum' - mainly because it-s higher nutritive value, as
higher total phenolic compounds, polyphenols and pronounced
antioxidant capacity.
Abstract: The paper proposes a methodology to process the signals coming from the Transcranial Magnetic Stimulation (TMS) in order to identify the pathology and evaluate the therapy to treat the patients affected by demency diseases. In particular, a fuzzy model is developed to identify the demency of the patients affected by Subcortical Ischemic Vascular Dementia (SIVD) and to measure the effect of a repetitive TMS on their motor performances. A tool is also presented to support the mentioned analysis.
Abstract: The multi-agent system for processing Bio-signals
will help the medical practitioners to have a standard examination
procedure stored in web server. Web Servers supporting any standard
Search Engine follow all possible combinations of the search
keywords as an input by the user to a Search Engine. As a result, a
huge number of Web-pages are shown in the Web browser. It also
helps the medical practitioner to interact with the expert in the field
his need in order to make a proper judgment in the diagnosis phase
[3].A web server uses a web server plug in to establish and
maintained the medical practitioner to make a fast analysis. If the
user uses the web server client can get a related data requesting their
search. DB agent, EEG / ECG / EMG agents- user placed with
difficult aspects for updating medical information-s in web server.
Abstract: The aim of this study was to remove the two principal
noises which disturb the surface electromyography signal
(Diaphragm). These signals are the electrocardiogram ECG artefact
and the power line interference artefact. The algorithm proposed
focuses on a new Lean Mean Square (LMS) Widrow adaptive
structure. These structures require a reference signal that is correlated
with the noise contaminating the signal. The noise references are
then extracted : first with a noise reference mathematically
constructed using two different cosine functions; 50Hz (the
fundamental) function and 150Hz (the first harmonic) function for
the power line interference and second with a matching pursuit
technique combined to an LMS structure for the ECG artefact
estimation. The two removal procedures are attained without the use
of supplementary electrodes. These techniques of filtering are
validated on real records of surface diaphragm electromyography
signal. The performance of the proposed methods was compared with
already conducted research results.
Abstract: Electromyography (EMG) is the study of muscles function through analysis of electrical activity produced from muscles. This electrical activity which is displayed in the form of signal is the result of neuromuscular activation associated with muscle contraction. The most common techniques of EMG signal recording are by using surface and needle/wire electrode where the latter is usually used for interest in deep muscle. This paper will focus on surface electromyogram (SEMG) signal. During SEMG recording, several problems had to been countered such as noise, motion artifact and signal instability. Thus, various signal processing techniques had been implemented to produce a reliable signal for analysis. SEMG signal finds broad application particularly in biomedical field. It had been analyzed and studied for various interests such as neuromuscular disease, enhancement of muscular function and human-computer interface.
Abstract: Prolonged immobilization leads to significant
weakness and atrophy of the skeletal muscle and can also impair the
recovery of muscle strength following injury. Therefore, it is
important to minimize the period under immobilization and accelerate
the return to normal activity. This study examined the effects of heat
treatment and rest-inserted exercise on the muscle activity of the lower
limb during knee flexion/extension. Twelve healthy subjects were
assigned to 4 groups that included: (1) heat treatment + rest-inserted
exercise; (2) heat + continuous exercise; (3) no heat + rest-inserted
exercise; and (4) no heat + continuous exercise. Heat treatment was
applied for 15 mins prior to exercise. Continuous exercise groups
performed knee flexion/extension at 0.5 Hz for 300 cycles without rest
whereas rest-inserted exercise groups performed the same exercise but
with 2 mins rest inserted every 60 cycles of continuous exercise.
Changes in the rectus femoris and hamstring muscle activities were
assessed at 0, 1, and 2 weeks of treatment by measuring the
electromyography signals of isokinetic maximum voluntary
contraction. Significant increases in both the rectus femoris and
hamstring muscles were observed after 2 weeks of treatment only
when both heat treatment and rest-inserted exercise were performed.
These results suggest that combination of various treatment techniques,
such as heat treatment and rest-inserted exercise, may expedite the
recovery of muscle strength following immobilization.
Abstract: The study of the variability of the postural strategies
in low back pain patients, as a criterion in evaluation of the
adaptability of this system to the environmental demands is the
purpose of this study. A cross-sectional case-control study was
performed on 21 recurrent non-specific low back pain patients and 21
healthy volunteers. The electromyography activity of Deltoid,
External Oblique (EO), Transverse Abdominis/Internal Oblique
(TrA/IO) and Erector Spine (ES) muscles of each person was
recorded in 75 rapid arm flexion with maximum acceleration.
Standard deviation of trunk muscles onset relative to deltoid muscle
onset were statistically analyzed by MANOVA . The results show
that chronic low back pain patients exhibit less variability in their
anticipatory postural adjustments (APAs) in comparison with the
control group. There is a decrease in variability of postural control
system of recurrent non-specific low back pain patients that can
result in the persistence of pain and chronicity by decreasing the
adaptability to environmental demands.
Abstract: This paper investigates the activity of the
gastrocnemius (Gas) muscle in healthy subjects during salat (ruku-
position) and specific exercise [Unilateral Plantar Flexion Exercise
(UPFE)] using electromyography (EMG). Both lateral and medial
Gas muscles were assessed. A group of undergraduates aged between
19 to 25 years voluntarily participated in this study. The myoelectric
activity of the muscles were recorded and analyzed. The finding
indicated that there were contractions of the muscles during the salat
and exercise with almost same EMG-s level. From the result,
Wilcoxon-s Rank Sum test showed no significant difference between
ruku- and UPFE for both medial (p=0.082) and lateral (p=0.226) of
GAS muscles. Therefore, salat may be useful in strengthening
exercise and also in rehabilitation programs for lower limb activities.
Abstract: Electromyography (EMG) signal processing has been investigated remarkably regarding various applications such as in rehabilitation systems. Specifically, wavelet transform has served as a powerful technique to scrutinize EMG signals since wavelet transform is consistent with the nature of EMG as a non-stationary signal. In this paper, the efficiency of wavelet transform in surface EMG feature extraction is investigated from four levels of wavelet decomposition and a comparative study between different mother wavelets had been done. To recognize the best function and level of wavelet analysis, two evaluation criteria, scatter plot and RES index are recruited. Hereupon, four wavelet families, namely, Daubechies, Coiflets, Symlets and Biorthogonal are studied in wavelet decomposition stage. Consequently, the results show that only features from first and second level of wavelet decomposition yields good performance and some functions of various wavelet families can lead to an improvement in separability class of different hand movements.
Abstract: SEMG (Surface Electromyogram) is one of the
bio-signals and is generated from the muscle. And there are many
research results that use forearm EMG to detect hand motions. In this
paper, we will talk about our developed the robot hand system that can
control grasping power by SEMG. In our system, we suppose that
muscle power is proportional to the amplitude of SEMG. The power is
estimated and the grip power of a robot hand is able to be controlled
using estimated muscle power in our system. In addition, to perform a
more precise control can be considered to build a closed loop feedback
system as an object to a subject to pressure from the edge of hand. Our
objectives of this study are the development of a method that makes
perfect detection of the hand grip force possible using SEMG patterns,
and applying this method to the man-machine interface.
Abstract: With getting older in the whole population, the
prevalence of stroke and its residual disability is getting higher and
higher recently in Taiwan. The functional electrical stimulation
cycling system (FESCS) is useful for hemiplegic patients. Because
that the muscle of stroke patients is under hybrid activation. The raw
electromyography (EMG) represents the residual muscle force of
stroke subject whereas the peak-to-peak of stimulus EMG indicates the
force enhancement benefiting from ES. It seems that EMG signals
could be used for a parameter of feedback control mechanism. So, we
design the feedback control protocol of FESCS, it includes
physiological signal recorder, FPGA biomedical module, DAC and
electrical stimulation circuit. Using the intensity of real-time EMG
signal obtained from patients, as a feedback control method for the
output voltage of FES-cycling system.
Abstract: The purpose of this study was to evaluate and
compare new indices based on the discrete wavelet transform
with another spectral parameters proposed in the literature as
mean average voltage, median frequency and ratios between
spectral moments applied to estimate acute exercise-induced
changes in power output, i.e., to assess peripheral muscle
fatigue during a dynamic fatiguing protocol. 15 trained
subjects performed 5 sets consisting of 10 leg press, with 2
minutes rest between sets. Surface electromyography was
recorded from vastus medialis (VM) muscle. Several surface
electromyographic parameters were compared to detect
peripheral muscle fatigue. These were: mean average voltage
(MAV), median spectral frequency (Fmed), Dimitrov spectral
index of muscle fatigue (FInsm5), as well as other five
parameters obtained from the discrete wavelet transform
(DWT) as ratios between different scales. The new wavelet
indices achieved the best results in Pearson correlation
coefficients with power output changes during acute dynamic
contractions. Their regressions were significantly different
from MAV and Fmed. On the other hand, they showed the
highest robustness in presence of additive white gaussian
noise for different signal to noise ratios (SNRs). Therefore,
peripheral impairments assessed by sEMG wavelet indices
may be a relevant factor involved in the loss of power output
after dynamic high-loading fatiguing task.