First Step to Human-Steering System Modelling and Control-Stretch Reflex Characteristic of Driver's Upper Limb Muscles

Author(s):  
Sitao Zhang ◽  
Yuan Chu ◽  
Xuewu Ji ◽  
Yosuke Nishimura ◽  
Atsushi Ishihara ◽  
...  
Author(s):  
R. Chen

ABSTRACT:Cutaneous reflexes in the upper limb were elicited by stimulating digital nerves and recorded by averaging rectified EMG from proximal and distal upper limb muscles during voluntary contraction. Distal muscles often showed a triphasic response: an inhibition with onset about 50 ms (Il) followed by a facilitation with onset about 60 ms (E2) followed by another inhibition with onset about 80 ms (12). Proximal muscles generally showed biphasic responses beginning with facilitation or inhibition with onset at about 40 ms. Normal ranges for the amplitude of these components were established from recordings on 22 arms of 11 healthy subjects. An attempt was made to determine the alterent fibers responsible for the various components by varying the stimulus intensity, by causing ischemic block of larger fibers and by estimating the afferent conduction velocities. The central pathways mediating these reflexes were examined by estimating central delays and by studying patients with focal lesions


2018 ◽  
Vol 4 (5) ◽  
pp. 7
Author(s):  
Shivam Dwivedi ◽  
Prof. Vikas Gupta

As the four-wheel steering (4WS) system has great potentials, many researchers' attention was attracted to this technique and active research was made. As a result, passenger cars equipped with 4WS systems were put on the market a few years ago. This report tries to identify the essential elements of the 4WS technology in terms of vehicle dynamics and control techniques. Based on the findings of this investigation, the report gives a mechanism of electronically controlling the steering system depending on the variable pressure applied on it. This enhances the controlling and smoothens the operation of steering mechanism.


Sensors ◽  
2021 ◽  
Vol 21 (6) ◽  
pp. 2146
Author(s):  
Manuel Andrés Vélez-Guerrero ◽  
Mauro Callejas-Cuervo ◽  
Stefano Mazzoleni

Processing and control systems based on artificial intelligence (AI) have progressively improved mobile robotic exoskeletons used in upper-limb motor rehabilitation. This systematic review presents the advances and trends of those technologies. A literature search was performed in Scopus, IEEE Xplore, Web of Science, and PubMed using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) methodology with three main inclusion criteria: (a) motor or neuromotor rehabilitation for upper limbs, (b) mobile robotic exoskeletons, and (c) AI. The period under investigation spanned from 2016 to 2020, resulting in 30 articles that met the criteria. The literature showed the use of artificial neural networks (40%), adaptive algorithms (20%), and other mixed AI techniques (40%). Additionally, it was found that in only 16% of the articles, developments focused on neuromotor rehabilitation. The main trend in the research is the development of wearable robotic exoskeletons (53%) and the fusion of data collected from multiple sensors that enrich the training of intelligent algorithms. There is a latent need to develop more reliable systems through clinical validation and improvement of technical characteristics, such as weight/dimensions of devices, in order to have positive impacts on the rehabilitation process and improve the interactions among patients, teams of health professionals, and technology.


QJM ◽  
2021 ◽  
Vol 114 (Supplement_1) ◽  
Author(s):  
Rasha M Ibrahim ◽  
Haitham M Hamdy ◽  
Amr A Mohammed ◽  
Ahmed M Elsadek ◽  
Ahmed M Bassiouny ◽  
...  

Abstract Background Limb-girdle muscular dystrophies (LGMDs) are a clinically and genetically heterogeneous group of disorders characterized by progressive muscle weakness and degenerative muscle changes. Studies have shown that ultrasound can be useful both for diagnosis and follow-up of LGMDs patients. Objectives This study aims to measure the sensitivity and the specificity of muscle ultrasound in assessment of suspected limb girdle muscular dystrophy patients. Subjects and Methods This cross-sectional descriptive study was conducted on Fifty-five patients with suspected LGMD from neuromuscular unit, myology clinic, Ain Shams University hospitals and eight healthy subjects. Age was above 2 years. Both sexes were included in the study. They underwent real-time B-mode ultrasonography performed with using Logiq p9 General Electric ultrasound machine and General Electric 7-11.5 MHZ linear array ultrasound probe. All ultrasound images have been obtained and scored by a single examiner and muscle echo intensity was visually graded semiquantitative according to Heckmatt's scale. The examiner was blinded to the muscle biopsy results and clinical evaluations. Results Statistical analysis revealed that the diagnostic performance of muscle US (Heckmatt’s score) in LGMD is most sensitive when calculated in all examined upper limb and lower limb muscles, followed by lower limb muscles alone. US of upper limb was found to be the least sensitive. Conclusions Muscle ultrasound is a practical and reproducible and valid tool that can be used in assessment of suspected LGMD patients.


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