Upper limb involuntary tremor reduction using cantilever beam TMDs

2022 ◽  
pp. 107754632110518
Author(s):  
Sarah Gebai ◽  
Gwendal Cumunel ◽  
Mohammad Hammoud ◽  
Gilles Foret ◽  
Emmanuel Roze ◽  
...  

Tuned mass dampers (TMDs) are proposed as a solution to reduce the involuntary tremor at the upper limb of a patient with postural tremor. The upper limb is modeled as a three-degrees-of-freedom rotating system in the vertical plane, with a flexion-extension motion at the joints. The measured extensor carpi radialis signal of a patient is used to excite the dynamic model. We propose a numerical methodology to optimize the parameters of the TMDs in the frequency domain combined with the response in the time domain. The objective function for the optimization of the dynamic problem is the maximum angular displacement of the wrist joint. The optimal stiffness and damping of the TMDs are obtained by satisfying the minimization of the selected objective function. The considered passive absorber is a cantilever beam–like TMD, whose length, beam cross-sectional diameter, and mass position reflect its stiffness for a chosen additional mass. A parametric study of the TMD is conducted to evaluate the effect of the TMD position along the hand segment, the number of TMDs, and the total mass of TMDs. The sensitivity of the TMD to a decrease of its modal damping ratio is studied to meet the range of stainless steel. TMDs are manufactured using stainless steel beams of the same length (9.1 cm) and cross-sectional diameter (0.79 mm), for which the mass (14.13 g) position is adjusted to match the optimal frequency. Three TMDs holding a mass of 14.13 g each cause 89% reduction in the wrist joint angular displacement.

Robotica ◽  
2014 ◽  
Vol 33 (1) ◽  
pp. 19-39 ◽  
Author(s):  
M. H. Rahman ◽  
M. J. Rahman ◽  
O. L. Cristobal ◽  
M. Saad ◽  
J. P. Kenné ◽  
...  

SUMMARYTo assist physically disabled people with impaired upper limb function, we have developed a new 7-DOF exoskeleton-type robot named Motion Assistive Robotic-Exoskeleton for Superior Extremity (ETS-MARSE) to ease daily upper limb movements and to provide effective rehabilitation therapy to the superior extremity. The ETS-MARSE comprises a shoulder motion support part, an elbow and forearm motion support part, and a wrist motion support part. It is designed to be worn on the lateral side of the upper limb in order to provide naturalistic movements of the shoulder (vertical and horizontal flexion/extension and internal/external rotation), elbow (flexion/extension), forearm (pronation/supination), and wrist joint (radial/ulnar deviation and flexion/extension). This paper focuses on the modeling, design, development, and control of the ETS-MARSE. Experiments were carried out with healthy male human subjects in whom trajectory tracking in the form of passive rehabilitation exercises (i.e., pre-programmed trajectories recommended by a therapist/clinician) were carried out. Experimental results show that the ETS-MARSE can efficiently perform passive rehabilitation therapy.


Sensors ◽  
2021 ◽  
Vol 21 (24) ◽  
pp. 8303
Author(s):  
Jia-Wen Yam ◽  
Jing-Wen Pan ◽  
Pui-Wah Kong

To better understand the biomechanics of para-table tennis players, this study compared the shoulder, elbow, and wrist joint kinematics among able-bodied (AB) and wheelchair players in different classifications. Nineteen participants (AB, n = 9; classification 1 (C1), n = 3; C2, n = 3; C3, n = 4) executed 10 forehand and backhand topspin drives. Shoulder abduction/adduction, elbow flexion/extension, wrist extension/flexion, respective range of motion (ROM), and joint patterns were obtained using inertial measurement unit (IMU) sensors. The results showed clear differences in upper limb kinematics between the able-bodied and wheelchair players, especially in the elbow and wrist. For the para-players, noticeable variations in techniques were also observed among the different disability classes. In conclusion, wheelchair players likely adopted distinct movement strategies compared to AB to compensate for their physical impairments and functional limitations. Hence, traditional table tennis programs targeting skills and techniques for able-bodied players are unsuitable for para-players. Future work can investigate how best to customize training programs and to optimize movement strategies for para-players with varied types and degrees of impairment.


2019 ◽  
pp. 121-131

Introduction: Breast cancer is the most common type of cancer among women in Brazil and in the worl. The surgical treatment procedure may cause severe morbidity in the upper limb homolateral to surgery, including the reduction of the range of motion, with consequent impairment of function. A physiotherapeutic approach has an important role in the recover range of motion and the functionality of these women, guaranteeing the occupational, domestestic, familiar and conjugated activities, and, in this way, also improving the quality of life. Objectives: To analyse chances in the shoulder's range of motion and the functional capacity of the upper limbs, promoted by the deep running procedure in women with late postoperative mastectomy. Methods: All the patients were submitted to an evaluation in the beginning and end of the treatment, including: goniometry of flexion, extension, abduction, adduction, internal and external rotation of the shoulder joint; and function capacity analysis in activities that involve the upper members by DASH questionnaire. The treatment protocol includes twelve sessions of deep running, realized twice a week, in deep pool, for 20-minute during six weeks. Results: Were submitted to treatment a total of 4 patients. Despite the improvement in the numerical values, statistically significant differences were not found on the range of movements and in the functional capacity of upper members before and after the deep running sessions in post-mastectomy women. Conclusion: Deep running had effects on the numerical values of range of movement and upper limb functionality in women in the late postoperative period of the mastectomy procedure, but without statistically significant differences.


2019 ◽  
Vol 23 (1) ◽  
Author(s):  
Ian T. Gatt ◽  
Tom Allen ◽  
Jon Wheat

AbstractThe hand-wrist region is reported as the most common injury site in boxing. Boxers are at risk due to the amount of wrist motions when impacting training equipment or their opponents, yet we know relatively little about these motions. This paper describes a new method for quantifying wrist motion in boxing using an electromagnetic tracking system. Surrogate testing procedure utilising a polyamide hand and forearm shape, and in vivo testing procedure utilising 29 elite boxers, were used to assess the accuracy and repeatability of the system. 2D kinematic analysis was used to calculate wrist angles using photogrammetry, whilst the data from the electromagnetic tracking system was processed with visual 3D software. The electromagnetic tracking system agreed with the video-based system (paired t tests) in both the surrogate (< 0.2°) and quasi-static testing (< 6°). Both systems showed a good intraclass coefficient of reliability (ICCs > 0.9). In the punch testing, for both repeated jab and hook shots, the electromagnetic tracking system showed good reliability (ICCs > 0.8) and substantial reliability (ICCs > 0.6) for flexion–extension and radial-ulnar deviation angles, respectively. The results indicate that wrist kinematics during punching activities can be measured using an electromagnetic tracking system.


2012 ◽  
Vol 159 ◽  
pp. 346-350
Author(s):  
Shu Min Liu ◽  
Jian Bin Zhang

The elevated temperature short-time tensile test with the sample of casting low nickel stainless steel was conducted on SHIMADZU AG-10 at ten temperatures 300, 500, 600, 700, 800, 950, 1000, 1050, 1100, and 1250°C, respectively. The stress-strain curves with the thermal deformation at the different temperatures, the peak stress intensity-temperature curve, and the reduction percentage of cross sectional area-temperature curve were obtained. Metallographic test samples were prepared and the morphology of deforming zone was observed by optical microscopy. The experimental results show that the tensile strength of the test samples decreases with increasing temperature. From 300 to 800°C, the work harding occurred and the tensile strength increases with increasing strain. The work softening occurred and the tensile strength decreases with increasing strain at temperatures of 800 to 1250°C. The minimum value of reduction percentage was measured at 800 °C. The austenite and delta-ferrite are the main phase in the tested samples. When the tensile temperatures are increased to 1200°C, the delta-ferrite became thinner and broke down to be spheroidized.


2021 ◽  
pp. 1-6
Author(s):  
Guillermo Mendez-Rebolledo ◽  
Ann M. Cools ◽  
Rodrigo Ramirez-Campillo ◽  
Elias Quiroz-Aldea ◽  
Fernanda A.P. Habechian

Context: Knowing the possible association between the isometric strength of the shoulder rotators, scapular muscles, and the Y-balance test upper quarter (YBT-UQ) performance could help identify which indicators of shoulder stability should be considered in this field test. This study aimed to determine whether the isometric strength of the shoulder rotators and scapular muscles is associated with the YBT-UQ performance of the dominant upper limb in amateur volleyball players. Design: Cross-sectional study. Methods: A convenience sample of 22 male and 18 female volleyball players (≥12 h of training/week) between 18 and 26 years of age. The isometric strength of the middle trapezius, lower trapezius, serratus anterior, internal, and external rotator muscles was assessed with a handheld dynamometer. Participants performed the YBT-UQ in the superolateral, medial, and inferolateral directions. The absolute isometric peak force (in Newtons) was normalized to body weight (in Newtons per kilogram) for each muscle test. For each YBT-UQ direction, the distance (in centimeters) was normalized for upper limb length (in percentage). A backward multiple linear regression analysis was used to determine the associations between variables. Results: The analysis revealed that the isometric strength of the lower trapezius (β = 26.82; 95% confidence interval, 21.24–32.40) is associated with inferolateral YBT-UQ performance (adjusted R2 = .706; P < .001). This factor explains 70% of the variability of the YBT-UQ in the inferolateral direction. Conclusions: Lower trapezius isometric strength is associated with inferolateral YBT-UQ performance of the dominant upper limb in amateur volleyball players. These findings could help in the development of more specific training programs and rehabilitation goals according to the performance of the athletes in the test.


2021 ◽  
Vol 8 (2) ◽  
pp. 84-90
Author(s):  
R Lalhminghlua ◽  
Mohammed Ziyauddin G Saiyed ◽  
Manjit Nayak ◽  
C B Jani

The outstretched arm span and measurement of components of the upper limb are a reliable predictors of stature when fragmentary remains of the human body are found. However, this relationship can be affected by age, sex, diet, racial and geographical differences, etc. Hence, a regional database is necessary to be more accurate. This cross-sectional, prospective analytical study included 200 students pursuing MBBS (Male = 100, Female = 100), natives of Gujarat, aged between 18 - 24 years with normal developmental history. Rich bells stature meter, Anthropometric metal rods (scaled), and Vernier caliper were used for taking measurements. SPSS software version 26 was used for statistical analysis. The findings showed a positive correlation between stature and the outstretched arm span as well as stature and various components of the upper limb. Except for the correlation between stature and the length of the shoulder to mid suprasternal notch in males, all of the results were statistically significant (p &#60; 0.05). Regression equations were derived and verified.Outstretched arm span is the most reliable indicator of stature whereas the length of the shoulder to mid suprasternal notch is the least reliable indicator of stature in both sexes in the natives of Gujarat. This study can be used as a reference in the future for medico-legal purposes.


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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