scholarly journals A biomechanical model via Kane’s equation – solving trunk motion with load carriage

2011 ◽  
Vol 2 (4) ◽  
pp. 678-685 ◽  
Author(s):  
Sharifah AbdulRahman ◽  
Azmin Rambely
Keyword(s):  
Biomechanical Model ◽  
Load Carriage ◽  
Trunk Motion ◽  
Equation Solving ◽  
Kane’S Equation

Effect of Load Carriage on the Backpack Vibration System

2012 ◽  
Vol 165 ◽  
pp. 295-299 ◽  
Author(s):  
Sharifah Alwiah Abdul Rahman ◽  
Azmin Sham Rambely ◽  
Rokiah Rozita Ahmad
Keyword(s):  
Body Weight ◽  
Fourier Series ◽  
The Body ◽  
Load Carriage ◽  
Spring Stiffness ◽  
Vibration System ◽  
Trunk Motion ◽  
Spring System ◽  
And Performance ◽  
Mass Spring

Vibration causes many problems in human health, comfort and performance. While walking with a backpack, movement of the backpack relative to the body causes a vibration which behaves like a spring that moves up and down following the motion of the body. In order to analyse the backpacks response to trunk motion, a backpack vibration system has been developed in this study. A model of a backpack-human trunk system, which is represented by a mass-spring system with a damper, and a Fourier series as an external force, is used to describe the motion of the vibration system. The vibration system was analysed using constant values of damping and spring stiffness (c=1 andk= 5) but with different values of the mass of the backpack. Increasing the mass of the backpack from 10% of body weight to 15 and 20% of body weight increased the amplitude of both the displacement and velocity of the backpack vibration system. However, the frequencies of the vibration system decreased as the mass of the backpack increased.

scholarly journals Study on improving three-dimensional dynamic simulation model and equation of flexible fabric

2019 ◽  
Vol 11 (6) ◽  
pp. 168781401985284
Author(s):  
Meiliang Wang ◽  
Mingjun Wang ◽  
Xiaobo Li
Keyword(s):  
Simulation Model ◽  
Dynamic Simulation ◽  
Material Properties ◽  
Three Dimensional ◽  
Equation Solving ◽  
Study Results ◽  
Essential Properties ◽  
Dynamic Simulation Model ◽  
Novel Model ◽  
Simulation Equation

The use of the traditional fabric simulation model evidently shows that it cannot accurately reflect the material properties of the real fabric. This is against the background that the simulation result is artificial or an imitation, which leads to a low simulation equation. In order to solve such problems from occurring, there is need for a novel model that is designed to enhance the essential properties required for a flexible fabric, the simulation effect of the fabric, and the efficiency of simulation equation solving. Therefore, the improvement study results will offer a meaningful and practical understanding within the field of garment automation design, three-dimensional animation, virtual fitting to mention but a few.

Effect of Load Carriage on the Respiratory Metabolism of Running Worker Ants of Camponotus herculeanus (Formicidae)

Oikos ◽  
1982 ◽  
Vol 39 (2) ◽  
pp. 137 ◽  
Author(s):  
Mogens G. Nielsen ◽  
Torben F. Jensen ◽  
Ib Holm-Jensen
Keyword(s):  
Load Carriage ◽  
Respiratory Metabolism

scholarly journals Estimation of Human Center of Mass Position through the Inertial Sensors-Based Methods in Postural Tasks: An Accuracy Evaluation

Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 601 ◽  
Author(s):  
Marco Germanotta ◽  
Ilaria Mileti ◽  
Ilaria Conforti ◽  
Zaccaria Del Prete ◽  
Irene Aprile ◽  
...  
Keyword(s):  
Inertial Sensors ◽  
Center Of Mass ◽  
Correlation Coefficients ◽  
Biomechanical Model ◽  
Lower Limbs ◽  
Accuracy Evaluation ◽  
Postural Tasks ◽  
Single Sensor ◽  
Using Data ◽  
Displacement Based

The estimation of the body’s center of mass (CoM) trajectory is typically obtained using force platforms, or optoelectronic systems (OS), bounding the assessment inside a laboratory setting. The use of magneto-inertial measurement units (MIMUs) allows for more ecological evaluations, and previous studies proposed methods based on either a single sensor or a sensors’ network. In this study, we compared the accuracy of two methods based on MIMUs. Body CoM was estimated during six postural tasks performed by 15 healthy subjects, using data collected by a single sensor on the pelvis (Strapdown Integration Method, SDI), and seven sensors on the pelvis and lower limbs (Biomechanical Model, BM). The accuracy of the two methods was compared in terms of RMSE and estimation of posturographic parameters, using an OS as reference. The RMSE of the SDI was lower in tasks with little or no oscillations, while the BM outperformed in tasks with greater CoM displacement. Moreover, higher correlation coefficients were obtained between the posturographic parameters obtained with the BM and the OS. Our findings showed that the estimation of CoM displacement based on MIMU was reasonably accurate, and the use of the inertial sensors network methods should be preferred to estimate the kinematic parameters.

scholarly journals Motor Adaptation to Cognitive Challenges and Destabilizing Treadmill Walking in Healthy Older Adults

2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 523-523
Author(s):  
Pei-Chun Kao ◽  
Michaela Pierro
Keyword(s):  
Older Adults ◽  
Cognitive Task ◽  
Daily Lives ◽  
Healthy Older Adults ◽  
Trunk Motion ◽  
Visual Color ◽  
Stability Data ◽  
Serial Addition ◽  
Task Conditions ◽  
Perturbed Walking

Abstract To develop effective fall prevention intervention, it is necessary to understand how older adults respond to challenges that demand cognitive-motor dual-tasking capability, an important capability in the daily lives. The purpose of this study is to investigate how older adults adjust their motor responses when encountering cognitive and walking perturbations simultaneously. We recorded kinematic data as subjects walked on a treadmill with or without 1) continuous random-amplitude treadmill platform sways (Perturbed vs. No-perturbed walking); and 2) each of the four cognitive tasks: Paced Auditory Serial Addition test (PASAT), clock test, visual color-word incongruent test (V-stroop), and auditory pitch-word incongruent test (A-stroop). We computed dynamic margins of stability (MOS), gait variability, and short-term local divergence exponent (LDE) of the trunk motion (local stability). Data of ten older subjects (age: 72.2±4.9) show that cognitive performance did not differ between standing, Perturbed or No-perturbed walking. Subjects demonstrated significantly greater local instability and variability in step measures, joint angle and MOS during Perturbed than No-perturbed walking (p<0.001). During dual-task conditions, subjects walked with significantly larger medio-lateral MOS (MOSML) compared to walking only, especially during early phase of the trial. During Perturbed walking, subjects had significantly larger MOSML during PASAT and Vstroop than walking only. Our data showed that subjects tried to increase their dynamic MOS during Perturbed walking or a cognitive task more difficult or taxing visual attention. However, the adjustments do not sustain throughout the trial. These findings suggest older adults tend to prioritize cognitive over walking tasks even when encountering walking perturbations.

Stability as a constraint in sagittal plane human force exertion modeling

1998 ◽  
Vol 1 (1) ◽  
pp. 23-39
Author(s):  
Carter J. Kerk ◽  
Don B. Chaffin ◽  
W. Monroe Keyserling
Keyword(s):  
Muscle Strength ◽  
Ankle Joint ◽  
Coefficient Of Friction ◽  
Sagittal Plane ◽  
Biomechanical Model ◽  
Whole Body ◽  
The Stability ◽  
Joint Center ◽  
Static Conditions ◽  
Stability Limits

The stability constraints of a two-dimensional static human force exertion capability model (2DHFEC) were evaluated with subjects of varying anthropometry and strength capabilities performing manual exertions. The biomechanical model comprehensively estimated human force exertion capability under sagittally symmetric static conditions using constraints from three classes: stability, joint muscle strength, and coefficient of friction. Experimental results showed the concept of stability must be considered with joint muscle strength capability and coefficient of friction in predicting hand force exertion capability. Information was gained concerning foot modeling parameters as they affect whole-body stability. Findings indicated that stability limits should be placed approximately 37 % the ankle joint center to the posterior-most point of the foot and 130 % the distance from the ankle joint center to the maximal medial protuberance (the ball of the foot). 2DHFEC provided improvements over existing models, especially where horizontal push/pull forces create balance concerns.

Rule-based Word Equation Solving

2020 ◽  
Author(s):  
Joel D. Day ◽  
Mitja Kulczynski ◽  
Florin Manea ◽  
Dirk Nowotka ◽  
Danny Bøgsted Poulsen
Keyword(s):  
Rule Based ◽  
Equation Solving ◽  
Word Equation

scholarly journals Practical Quantum Computing

2021 ◽  
Vol 2 (1) ◽  
pp. 1-35
Author(s):  
Adrien Suau ◽  
Gabriel Staffelbach ◽  
Henri Calandra
Keyword(s):  
Wave Equation ◽  
Quantum Computer ◽  
Quantum Algorithms ◽  
Quantum Algorithm ◽  
Quantum Circuit ◽  
Equation Solving ◽  
Small Quantum ◽  
Quantum Wave ◽  
Variational Algorithms ◽  
The One

In the last few years, several quantum algorithms that try to address the problem of partial differential equation solving have been devised: on the one hand, “direct” quantum algorithms that aim at encoding the solution of the PDE by executing one large quantum circuit; on the other hand, variational algorithms that approximate the solution of the PDE by executing several small quantum circuits and making profit of classical optimisers. In this work, we propose an experimental study of the costs (in terms of gate number and execution time on a idealised hardware created from realistic gate data) associated with one of the “direct” quantum algorithm: the wave equation solver devised in [32]. We show that our implementation of the quantum wave equation solver agrees with the theoretical big-O complexity of the algorithm. We also explain in great detail the implementation steps and discuss some possibilities of improvements. Finally, our implementation proves experimentally that some PDE can be solved on a quantum computer, even if the direct quantum algorithm chosen will require error-corrected quantum chips, which are not believed to be available in the short-term.

Sign in / Sign up

Export Citation Format

Share Document