Motion capture and myoelectric multimodal measurements during static and dynamic bending tasks using a back assisting exoskeleton: a preliminary study

2021 ◽  
Author(s):  
Zakaria Jelti ◽  
Kevin Lebel ◽  
Berenger LETELLIER ◽  
Pierre R. Slangen
Keyword(s):  
Motion Capture ◽  
Preliminary Study ◽  
Dynamic Bending

scholarly journals Biomechanical Role and Motion Contribution of Ligaments and Bony Constraints in the Elbow Stability: A Preliminary Study

2019 ◽  
Vol 6 (3) ◽  
pp. 68 ◽  
Author(s):  
Elisa Panero ◽  
Laura Gastaldi ◽  
Mara Terzini ◽  
Cristina Bignardi ◽  
Arman Sard ◽  
...  
Keyword(s):  
Motion Capture ◽  
Elbow Joint ◽  
Large Deflection ◽  
Elbow Flexion ◽  
Elbow Instability ◽  
Joint Stability ◽  
Coronoid Fracture ◽  
Flexion Extension ◽  
Preliminary Study ◽  
Functional Investigation

In flexion–extension motion, the interaction of several ligaments and bones characterizes the elbow joint stability. The aim of this preliminary study was to quantify the relative motion of the ulna with respect to the humerus in two human upper limbs specimens and to investigate the constraints role for maintaining the elbow joint stability in different section conditions. Two clusters of four markers were fixed respectively to the ulna and humerus, and their trajectory was recorded by a motion capture system during functional orthopedic maneuver. Considering the posterior bundle of medial collateral complex (pMUCL) and the coronoid, two section sequences were executed. The orthopedic maneuver of compression, pronation and varus force was repeated at 30°, 60° and 90° flexion for the functional investigation of constraints. Ulna deflection was compared to a baseline elbow flexion condition. With respect to the intact elbow, the coronoid osteotomy influences the elbow stability at 90° (deflection = 11.49 ± 17.39 mm), while small differences occur at 30° and 60°, due to ligaments constraint. The contemporary pMUCL section and coronoid osteotomy causes elbow instability, with large deflection at 30° (deflection = 34.40 ± 9.10 mm), 60° (deflection = 45.41 ± 18.47 mm) and 90° (deflection = 52.16 ± 21.92 mm). Surgeons may consider the pMUCL reconstruction in case of unfixable coronoid fracture.

scholarly journals Design of a Novel Wearable System for Foot Clearance Estimation

Sensors ◽  
2021 ◽  
Vol 21 (23) ◽  
pp. 7891
Author(s):  
Shilpa Jacob ◽  
Geoff Fernie ◽  
Atena Roshan Fekr
Keyword(s):  
Motion Capture ◽  
Small Scale ◽  
Wearable System ◽  
Gait Parameters ◽  
Foot Clearance ◽  
Preliminary Study ◽  
Offset Compensation ◽  
Walking Speeds ◽  
Future Work ◽  
Healthy Females

Trip-related falls are one of the major causes of injury among seniors in Canada and can be attributable to an inadequate Minimum Toe Clearance (MTC). Currently, motion capture systems are the gold standard for measuring MTC; however, they are expensive and have a restricted operating area. In this paper, a novel wearable system is proposed that can estimate different foot clearance parameters accurately using only two Time-of-Flight (ToF) sensors located at the toe and heel of the shoe. A small-scale preliminary study was conducted to investigate the feasibility of foot clearance estimation using the proposed wearable system. We recruited ten young, healthy females to walk at three self-selected speeds (normal, slow, and fast) while wearing the system. Our data analysis showed an average correlation coefficient of 0.94, 0.94, 0.92 for the normal, slow, and fast speed, respectively, when comparing the ToF signals with motion capture. The ANOVA analysis confirmed these results further by revealing no statistically significant differences between the ToF signals and motion capture data for most of the gait parameters after applying the newly proposed foot angle and offset compensation. In addition, the proposed system can measure the MTC with an average Mean Error (ME) of −0.08 ± 3.69 mm, −0.12 ± 4.25 mm, and −0.10 ± 6.57 mm for normal, slow, and fast walking speeds, respectively. The proposed affordable wearable system has the potential to perform real-time MTC estimation and contribute to future work focused on minimizing tripping risks.

scholarly journals Jumping Side Volley in Soccer – A Biomechanical Preliminary Study on the Flying Kick and Its Coaching Know-How for Practitioners

2020 ◽  
Author(s):  
Xiang Zhang ◽  
Gongbing Shan ◽  
Feng Liu ◽  
Yaguang Yu
Keyword(s):  
Motion Capture ◽  
Learning Strategy ◽  
Biomechanical Modeling ◽  
Trunk Rotation ◽  
Know How ◽  
Risk Of Injury ◽  
Preliminary Study ◽  
3D Motion Capture ◽  
Ball Motion ◽  
Full Body

Jumping side volley has created breathtaking moments and cherished memories for us. Regrettably, a scientific study on the skill has not been found in literature. Relying on talent of athletes to improvise on the fly can hardly be considered a viable learning strategy. This study targets to fill the gap by quantifying factors contributing to develop its coaching method. Using 3D motion capture (12-cameras, 200Hz) and full-body biomechanical modeling, our study aimed to identify elements that govern entrainment of the skill by examining jumping, kicking and falling phases of its execution. Given the rarity of players who have acquired this skill, we found five subjects for the study. Twenty-three trials were captured and quantified. The results unveil the following key elements: 1) the control of trunk rotation during the jumping, 2) the angle between thighs upon take-off, 3) the whip-like control of the kicking leg during airborne, 4) timing between ball motion and limbs’ coordination, and 5) damping mechanism during falling. An accurate kick can only be achieved through repetitive training. This underlines the need for athletes to master a safe landing technique that minimizes risk of injury during practice. Therefore, training should begin with learning a safe falling technique.

scholarly journals Trajectory Generation from Motion Capture for a Planar Biped Robot in Swing Phase

2015 ◽  
Vol 11 (22) ◽  
pp. 25-47 ◽  
Author(s):  
Diego A. Bravo M. ◽  
Carlos F. Rengifo R.
Keyword(s):  
Motion Capture ◽  
Biped Robot ◽  
Swing Phase ◽  
Human Motion ◽  
Torque Control ◽  
Hybrid Strategy ◽  
Time Scaling ◽  
Preliminary Study ◽  
Reference Trajectories ◽  
Computed Torque

This paper proposes human motion capture to generate movements for theright leg in swing phase of a biped robot restricted to the sagittal plane.Such movements are defined by time functions representing the desiredangular positions for the joints involved. Motion capture performed witha Microsoft KinectTMcamera and from the data obtained joint trajec-tories were generated to control the robot’s right leg in swing phase. Theproposed control law is a hybrid strategy; the first strategyis based ona computed torque control to track reference trajectories,and the secondstrategy is based on time scaling control ensuring the robot’s balance. Thiswork is a preliminary study to generate humanoid robot trajectories frommotion capture.

The Ultrastructure of Metastatic Human Mammary Carcinoma After Prolonged Estrogen Therapy

1967 ◽  
Vol 25 ◽  
pp. 180-181
Author(s):  
John H.L. Watson ◽  
John L. Swedo ◽  
R.W. Talley
Keyword(s):  
Mammary Carcinoma ◽  
Osmium Tetroxide ◽  
Estrogen Therapy ◽  
Ultrastructural Level ◽  
Uranyl Acetate ◽  
Human Mammary Carcinoma ◽  
Surgical Biopsy ◽  
Lead Hydroxide ◽  
Preliminary Study ◽  
Hormonal Therapies

A preliminary study of human mammary carcinoma on the ultrastructural level is reported for a metastatic, subcutaneous nodule, obtained as a surgical biopsy. The patient's tumor had responded favorably to a series of hormonal therapies, including androgens, estrogens, progestins, and corticoids for recurring nodules over eight years. The pertinent nodule was removed from the region of the gluteal maximus, two weeks following stilbestrol therapy. It was about 1.5 cms in diameter, and was located within the dermis. Pieces from it were fixed immediately in cold fixatives: phosphate buffered osmium tetroxide, glutaraldehyde, and paraformaldehyde. Embedment in each case was in Vestopal W. Contrasting was done with combinations of uranyl acetate and lead hydroxide.

Fine structure of early degenerating myofibers in the tibialis anterior of young ‘MDX’ mouse

1988 ◽  
Vol 46 ◽  
pp. 322-323
Author(s):  
H.D. Geissinger ◽  
C.K. McDonald-Taylor
Keyword(s):  
Fine Structure ◽  
Muscle Regeneration ◽  
Tibialis Anterior ◽  
Genetic Defect ◽  
Mdx Mouse ◽  
Mdx Mice ◽  
Histopathological Changes ◽  
Electron Microscopic ◽  
Dystrophic Mouse ◽  
Preliminary Study

A new strain of mice, which had arisen by mutation from a dystrophic mouse colony was designated ‘mdx’, because the genetic defect, which manifests itself in brief periods of muscle destruction followed by episodes of muscle regeneration appears to be X-linked. Further studies of histopathological changes in muscle from ‘mdx’ mice at the light microscopic or electron microscopic levels have been published, but only one preliminary study has been on the tibialis anterior (TA) of ‘mdx’ mice less than four weeks old. Lesions in the ‘mdx’ mice vary between different muscles, and centronucleation of fibers in all muscles studied so far appears to be especially prominent in older mice. Lesions in young ‘mdx’ mice have not been studied extensively, and the results appear to be at variance with one another. The degenerative and regenerative aspects of the lesions in the TA of 23 to 26-day-old ‘mdx’ mice appear to vary quantitatively.

Ultrastructural observations of the aorta of calves implanted with a mechanical left ventricular assist device

1990 ◽  
Vol 48 (3) ◽  
pp. 834-835
Author(s):  
J P Cassella ◽  
V Salih ◽  
T R Graham
Keyword(s):  
Left Ventricular Assist Device ◽  
Ventricular Assist Device ◽  
Left Ventricular ◽  
Aortic Tissue ◽  
Assist Device ◽  
Ventricular Assist ◽  
Transmission Electron ◽  
Left Ventricular Assist ◽  
Preliminary Study

Left ventricular assist systems are being developed for eventual long term or permanent implantation as an alternative to heart transplantation in patients unsuitable for or denied the transplant option. Evaluation of the effects of these devices upon normal physiology is required. A preliminary study was conducted to evaluate the morphology of aortic tissue from calves implanted with a pneumatic Left Ventricular Assist device-LVAD. Two 3 month old heifer calves (calf 1 and calf 2) were electively explanted after 128 days and 47 days respectively. Descending thoracic aortic tissue from both animals was removed immediately post mortem and placed into karnovsky’s fixative. The tissue was subsequently processed for transmission electron microscopy (TEM). Some aortic tissue was fixed in neutral buffered formalin and processed for routine light microscopy.

Sign in / Sign up

Export Citation Format

Share Document