Questions related to Biomechanical Analysis
Hi all, my current thoughts include
- Experimentally filming and motion tracking people leaning on walls/pushing weights, then using k=f/(initial - final distance)
- Energy methods: change in kinetic energy = potential energy (in a spring), then solve 1/2kx^2 = 1/2mv^2 for the stiffness, k.
- An alternative energy method: Castigliano's theorem?
- Spring tension = inertial forces (i.e. D'Alembert's Principle) + body force (i.e. weight)
- Simulation using FEA, probably including multibody dynamics and rigid bodies for everything other than the arm.
Is there a method (of using any of the above) to understand the non-linearities that might be expected in a human ligament?
Please can I get any other suggestions you might have or comments on the above?
I am looking for a research work that implemented an uncertainty or statistical framework to study the impact of the geometric parameters on the fracture response.
I appreciate any help.
Thank you in advance,
Whether Acoustic Vibrations can be used to damage / fracture the CORONA VIRUS (COVID-19) structure ?
Acoustics with resonance frequency of the COVID-19 can be used to prevent this Pandemic ?
I am working on a project on designing and testing new materials and different structure(3D-infill) configurations as prototypes for the mid-sole of a running shoe.
I was wondering about the functional properties that would be required from the mid-sole of a shoe to optimize its performance.
Any leads regarding mechanical/functional properties of running shoes, midsoles or regarding mechanical testing of midsoles would be very helpful.
Kicking ability represents the most important soccer-specific skill, since it is used not only in passes, crosses, clearances, and also to score goals.
The ability to kick equally with both the preferred and non-preferred leg leads to an advantage for soccer players, since it increases the number of scoring opportunities. In modern football, this ability is becoming even more important as there is less space and time for players to decide what we do with the ball. In fact, there is positive relationship between player’s salary and ability to use two feet in professional soccer.
However, ball velocity is significantly lower after a kick with the non-preferred leg in comparison to the preferred one.
It’s known that two-footedness can be developed, to some extent, by training. But it would be possible to develop two-footed players in soccer club academys? Why don't we teach our soccer players to use both feet equally well?
I am trying to apply material mapping to the vertebral model. I exported image data and surface model (.stl) from the 3D slicer, but when the same are imported IA-Femesh, there is no overlap, so cannot apply the image intensity based properties.
Can you please help me to resolve this issue.
Is it possible to link the IA-FEMesh to 3D slicer?
I'm trying to simulate a static load being applied into a hip geometry where femur bone (sphere geometry) and pelvis bone(hemisphere geometry) are having contact through a frictionless environment.
My Boundary Conditions are the following:
- Distributed force applied through a kinematic coupling constraint on a surface(pelvis).
- No translation or rotation allowed on a surface (femur)
- Surface-to-surface frictionless contact.
I'm using tetrahedral C3D10 elements with a fine mesh due to the irregular shape of the geometries and their difficulty to partition in order to obtain a structured mesh.
The main convergence problem is that ABAQUS reaches the maximum number of attempts (5) for an increment without finding a solution[cut-backs]. I've seen some advice where they suggest the following:
-Modifying a mesh to a structured one
- In case of tetrahedral elements, use a very fine mesh.
- Modify algorithm such as increment attempts, reducing time increment and on.
- Decompose my load into more steps to overcome the critical point.
I haven't been able to succeed yet by trying some of those. Does anyone has a particular suggestion?
I'm trying to synchronize imu sensor with the Motion Capture system. Is this possible? If so, how?
thanks for answering
I am looking to sync data across an ultrasound machine (Terason USmart 3300), Vicon motion capture, force plate, and Delsys EMG data. I have gotten the Vicon, force plate, EMG to sync within a Vicon program, but am looking to add ultrasound to it. Terason has told me it is not possible unless I alter the unit (which they will do and charge me for). I am hoping that it is possible to do it without that expense (since it is not just my lab's unit).
I am looking to see if anyone has done this? I was thinking I could maybe get a digital to analog converter that would allow me to connect it to the trigger that is already hooking up the other devices (Vicon only allows me to add a "generic analog device" in the program). This Terason unit is extremely clinical and does not have any wires that would allow me to hook it up. I have seen some "Trigno wire" devices that seem to fix that problem, but not sure if that would be enough of a solve.
Alginate is an anionic polymer and on the other hand Rhodamine B is a cationic dye. Theoretically these two should be boned by ionic bond. Does it happen? More suggestions and experience are greatly appreciated. Advanced thanks!!
Have you, or anybody you can recommend, published applied biomechanics research conducted at least in part as an undergraduate?
If so, please get in touch or recommend others.
I'm asking for 5 mins to complete a survey on your experiences to help others.
I'll get in touch with the survey link (not posting publicly to ensure genuine responses / inclusion criteria are met).
I want an initial direction, like how can I use IMU sensors on knees (e.g upper leg and lower leg ) to estimate body state e.g running, walking, climbing, etc. The basic idea I have is to use 2 IMU sensors on knee position (upper and lower leg) , and to get data or make a data set of it. Then process it using deep learning e.g CNN or ANN etc. But point is..are there data sets available on which I can test CNN etc to see either it works or not. Need guidance about data sets, from where could I get IMU knee based data sets, so that I can focus on my algorithm only.
I am planning a study on freezing in patients with Parkinson’s disease. I need basic parameters including and especially time taken to initiate walking.
What is the most affordable way to conduct such gait analysis? Insoles? Affordable gait mats?
Thanks for your response in advance,
I'm using abaqus dynamic implicit solver to analyze hip joint. There is not problem like this with static step. but i have to use time depended loads. so when i use dynamic implicit; there are stresses only in force applied area but no stress or displacement in anywhere else. i also tried with dynamic explicit step and concentrated and pressure loads but the problem didnt solve.
i've used frictionless surface to surface contact and fixed a region far from load applied area. and material properties defined by mimics software.
i'll also add a photo and abaqus files fore details. thanks alot for your help.
Anybody has/had been working for the subject topic primarily for the FE/XFEM study and the associated software. Need suggestions for existing models/codes and/or review papers.
Muscle tissue does not normally produce electrical signals during rest. So its expected that the value Amplitude in mV will be roughly 0. However when muscles are stiff is when your muscles feel tight and you find it more difficult to move than usual, especially after rest. You may also have muscle pains, cramping, and discomfort. Cramps, which acts like muscle stiffness, can occur when muscles are unable to relax properly due to myosin fiber's not fully detaching from actin filaments. In skeletal muscle, ATP must attach to the myosin heads for them to disassociate from the actin and allow relaxation — the absence of ATP in sufficient quantities means that the myosin heads remains attached to actin. So will there be an expected amplitude in mV well greater than 0, maybe 3 to 5 mV range.
The tibia is the most commonly broken major bone in the leg. Displaced distal tibia shaft fractures are effectively treated with standard plates or intramedullary nails. which one is more preferable?
I am trying to model the behavior of a deformable object with a discrete rigid plate and am getting these warnings:
The master surface assembly_surf-plate does not exist.
Analysis Input File Processor exited with an error.
Does anyone know how to solve this?
According to ISO 7206-12 standard, for acetabular shell deformation test, which material is more risky, having the smallest diameter or the biggest diameter?
Note: The thickness values are the same.
What process or mechanism would be taken?
We want to identify people by their gait cycle video.
Do people have a unique gait cycle?
Is there any software to simulate the gait cycle and analyze it using a video of a person's walking cycle?
I'm working on a biomechanical project. In fact I'm want to design a mechanical robot to simulate human gate in positions of walking and running. So I need to record human gate in different speeds and analyze the movement of COM and some specific joints and organs after that.
Can you suggest a required way (tools, devices, software or...) for this project?
I am preparing electrospun nanofiber samples for mechanical analysis. The meshes are collected on Aluminum foil, and it is so difficult to detach them from it to proceed the analysis.
I have done many trials using adhesive tapes but the scaffolds didn't detach well from the Al foil. Moreover, I tried to hydrate the samples with physiological solution, waiting to dehydrate and then taking them off from Al foil, but also this technique didn't work because once the scaffold become dehydrated, it attached to the Al foil making its collection difficult.
Please can anyone give me any suggestion to solve this problem??
I would like to mention that I have 2 different types of scaffolds (randomly oriented and highly aligned fibers)
Thank you in advance
We usually find many papers on theory or experimental researches about nano/microcantilever biosensors. Nevertheless, it is important for me to know which companies are working on it to improve this device for commercial goals?
Is there a final form of this device or technology?
Has this device ever been used in a clinic or hospital complex?
I ask about the convenient test to evaluate the leg power in sports, and the relationship between horizontal, vertical jump and leg power.
Osteoarthritis (OA) is a common occupational dangerous case for service members. I wanted to know how body borne load impacts knee biomechanics for participants who do and do not present varus thrust during running.
The test person’s right knee had a meniscal tear three times before the measurement. The last meniscal tear (always on the right knee) happened 2016.
Test person A: male, 25 years of age, 180cm, 89kg
The test person had to squat at a rhythm of 20 beats per minute (BPM). In other words, the participant had to perform one squat within 3 seconds. The measurement is finished till the test person is not able to keep the rhythm for his squats. This was the case after 103 squats. In addition to that, a chair was placed behind the participant as an orientation for the downward movement to squat always at the same height .
I'm trying to find out the differences in muscular activity and muscular fatigue during the same movement of m. rectus femoris / m. vastus lateralis of the test persons postsurgical and uninjured knee (leg). Maybe someone already has experience with these injuries.
I evaluated the measurement data (Matlab, STFT) from the EMG and they look like in the following way.
Vastus lateralis and rectus femoris from the right leg (postsurgical) occured to work in a much higher muscular frequency than the uninjured left leg. I'm not sure why this is the case and which role the meniscal tear takes in.
I need to know which sEMG descriptors are useful to determine motor unit recruitment or activation of a certain muscle. In our study, we want to see how the pattern of activation / recruitment differs between different inter-electrode distance (IED) and different intensities using an electrostimulator to cause muscle contraction.
In brief, we want to see if different intensities of electrostimulation (50, 75 and 100 mA) with different IED differ in the recruitment of motor units or something similar (i.e., any sEMG useful descriptor for this purpose).
What are the more important requirement needed during the measuring of the interface pressure for the patient using ankle foot ortheses ?
How can the modeling of the residual lower limb amputation be performed below the knee under consideration the effect of thermal distribution resulting from the tissues, muscles, veins and arteries as a heat source?
Mostly in mathematical modelling of muscle strength by Marras and Granata this term PCSA has been used. I want to know how do we find the exact PCSA. or is it just an average from cadaver studies.
I have a set of EMG data from incremental pedaling from the quadriceps muscles. I need to predict the muscle fatigue from the analyses of EMG data. I could not find a change in parameters like median frequency or Zero crossing to identify fatigue threshold. I believe these are usual in Isometric contractions.
Pressure insoles (or force insoles) are devices made to measure the reaction forces of the ground. They are built to measure how much pressure does the body produce and how its distributed on the surface of the device, when the foot contacts the ground, and this allows to measure balance with specific parameters like the Center Of Pressure (COP).
Some studies have used these devices to meassure the COP on static(Standing position) and dynamic balance(Walk, jump, run). Activities like Walking, and running have some phases on its movements when one foot (or even both of them) is not doing contact with the ground, but still the insoles record some residual pressure in this moment. Depending on how much time are we recording, does it imply that the residual pressure recorded is going to change the outcome in a significative way? if this happens, should researchers delete this remaining data?
The center of pressure (COP) is the point on a surface where the total sum of the resultant forces can act with the same magnitude of the force which is distribuited on the surface of an object. Measuring the COP has been used in biomechanics as a way to measure the postural balance in humans. There's been created variables or parameters related to the COP, in order to measure postural balance (e.g. COP Velocity, COP Displacement, COP Trayectory). Some studies have used one or more of this parameters with the purpose of investigate postural balance. But Which of this COP parameters is more usefull to reflect the COP behavior? Are there better parameters than others or maybe each parameter is better measuring balance in an specific task or context?
Prefer an exhaustive text book which is written as an introductory text and explain the concept of strain energy in details and multiple models, derivation and limitations.
I want to process biomedical data on LABview 8.5. I tried to download the VI's but they don't work. Are they only for the newer versions of LABview. If they are: Can I get such a toolkit for my version?
In several studies which aim is to test or evaluate static or dynamic balance, is usual that the measuring tool are force plates, platforms or pressure insoles. In order to perform the balance recording, the researchers have to set the appropiate settings, which includes the sampling rate. Some studies had reported sampling rates ranging from 200 to 1000 Hz or more, depending on the tool.
Having in count that each one of the main sensory systems involved is supose to react and modulate balance at very low frequencies (compared to the sampling rate that the measuring tools usually have in most of the studies), is it really necessary to set the sampling rate to high?
There are lots of papers about researchers which investigated how does the COP behave in some postures (like unipedal or bipedal standing), and functional activities (like walking) on healthy population. Another activity related to the daily living is going up and down stairs, which of course allow us to get to some point (high or down in a building, for example) in case there is not an elevator or other devices that allow us to get there. Furthermore most of the buildings around us (even our own houses) have stairs on them, so we have to deal with that structure.
There are some studies which have investigated the kinetic and kinematic parameters, angles and other properties related to the stair descent. I´m interested in knowing how the COP parameters (Ap/Ml Displacement, Velocity, and trace length) behaves in this activity
HUMOS 2 model is developed under a European Framework program and used in numerous publications since early 2000's. Unfortunately, I could not find a reference on how the model it self can be accessed. Any help is appreciated.
I am working on a thesis about how different hand tool designs affect the pressure distribution over the palm of the hands. However, it is somewhat difficult to get references about how excessive pressures may impair the use of a product and what are its implications on hands, in a physiological level (like schemias, calluses, etc.). I found only very sparse mentions of pressure in some texts, like Cacha and Tichauer and Gage. One reference that may be helpful is the one listed below, but I can't get my hands on it:
Mechanical considerations of skin in work. AMERICAN JOURNAL OF INDUSTRIAL MEDICINE. Volume 8, Issue 4-5, 1985, Pages: 463–472, Thomas J. Armstrong
Article first published online : 11 JAN 2007, DOI: 10.1002/ajim.4700080428
Does someone have it or know any reference that may help me in this way?
Chapter 4: Simulation of a Lumbar Motion Segment
vertebral_body_input.dat -- Input file for the lumbar motion segment simulation.
vertebral_body.cdb -- Common database file for the lumbar motion segment model (called by the vertebral_body_input.dat file).
The files are available in the td-10 folder. See Obtaining the Input Files for more information.
side deviations For line work Force leads to weakness in the Force while running and throwing during movement
Man of 58 years-old with trauma (D12 vertebral fracture, fractured left shoulder blade, multiple rib fractures on the left). The scapular fracture treated with immobilization for 30 days (orthopedic). The patient has undergone neurosurgery of reduction / stabilization of the fracture with screws transpedicular D12 D11-D12 L1e kyphoplasty (duration surgery - 1 hour and 25 minutes, anesthesia duration - 2 hours and 15 minutes). The patient was placed in the prone position with the head resting on blankets and turned to the left. Immediately after the operation, during arousal, the patient experienced pain in the left eye, edema and amaurosis. He underwent angiography which showed signs of retinopathy in both eyes and a central retinal artery occlusion in the left eye (CRAO).The patient is diabetic with insulin pump therapy, hyperlipidemic (rosuvastatina), hypertension, occasional smoker or former smoker, hyperhomocysteinemia, assumes Cardioaspirin. The doppler has revealed a thickening of the left carotid artery with a fibro-calcific plaque without significant impairment of flow. In addition, both the CT that the brain MRI showed multiple small areas of gliosis of the white matter, as from vascular cerebral disease. According to your experience, could the prone position to have been the only cause of ocular damage?
I need to a) know if its built-in hardware circuit network amplify the raw signal and b) if its built-in hardware circuit network convert the raw signal to an average root-mean-square (rms).
Suppose I am given a motion data file (say AMC) that is without the translation/rotation of the overall skeleton. If I only know the joint angles, how do I compute the overall translation and orientations of the figure? I have some idea. To calculate walking distance for example, I would need to calculate the stride length (how to determine a stride?) and the number of strides per unit time. To calculate the body orientation, I should compute the length and orientation of the leg limb at the point of foot-ground contact, and to calculate the body position during the flight phase (in running), I will need the velocity of the feet upon take-off and compute the force. But I'm interested to know if there's certain subtlety or if there is is some explanation or example calculations anywhere. Thanks.
Currently most of the material models available for bone are linear elastic with E nd v. Are there any better models available for representing bone in Abaqus like concrete damage plasticity etc.
Do all bones have same material properties or are these very site specific.
I am developing a FE model of lumbar spine. Has anyone developed a model using tetrahedral mesh. Most of the papers which I read have used hex mesh. I wanted to know the advantage and disadvantages of both the meshes while developing a model.
Also I want to know how to go about in making the inter vertebral disc. I have read about mesh interpolation techniques which are used for this , I guess it wont work with tet mesh.
thanks and regards
There are more studies explaining about chronic pain and inability of patient to repeat the Joint Re position test in both cervical and Lumbar region. I would like to know how can we measure it precisely in clinical set up. Any reliable scale to grade the error?
Looking for a start up to quantify the harmony between a carrying system (e.g. leaf blower) using acceleration sensors. In a first approach a attached a sensor to the sternum and a second sensor close to the centre of mass of the device. Both sonsor's coordinate systems have had teh same orientation. Analysis of the signals came up with questions such as "How can a improve the position of the sensors?" and " Which parameter is suitable for the assessment of a comfortable fit"? Thanks for any help.
I am looking at an innovative way to present some data for a article I am currently writing. I have measured the impact point between a putter and golf ball using a mechanical putting robot, whereby stroke kinematics are standardised. Along with human participants where variation has occurred with stroke kinematics. To present the differences between the two I'd like to map them through a stereographic projection. I don't have access to MATLAB unfortunately so am looking for alternative methods to complete this if possible.
I assessed biomechanical parameters during running and I would like to estimate joint stiffness. Is it possible? If yes, how should I do it?
Is there some paper talking about this?
Thank you very much!
We conducted a study, where three investigators with different experience levels measured joint range of motions. We calculated the ICC an 95% for each combination of the there investigators (s. table). We found significant differences when looking at the 95% CI. (do you know a test to calculate?)
We now want to calculate norm values. Should we use the mean values of the three investigators with different skill sets or the mean of the two investigators with the highest ICC scores (All vs. HP-SFB)?
Thank you very much for your help!
I would like to know about various researches happening around the world to determine maximum torque that can be exerted by human hands to rotate a hand wheel.
The result of one such research is provided in the link below:
Any update on same type of research is appreciated.
Thank you in advance.
Greetings, I am interested in creating a full body model for Vicon (With Marker set) using the clusters to find the joint center unlike the plug in gait model which has got individual and wand markers.
The idea is to find the reliable joint center for all the major joints thereby reducing the error percentage in the 3D motion analysis (especially in terms of angle interpretations).
While post capturing the same data can be imported into matlab to find the angles and associated graphs for the same.
I will be more than happy to go on with a collaborative study on this.
According to strain-stress diagram of the Achilles tendon, one can consider one linear and one nonlinear part before rupture. It is important to see which of these two area should be considered in vibration analysis.
Is there any study (book, paper, etc) reporting that how much strain (what percent) occurs during running?
Thank you in advance
I want to work on human motion using three-axis acceleration, but I do not have a standard dataset. Do you know any dataset in this feild?
I am trying to measure plantar pressure in badminton players when they make the shift to the net for linking with lower body injuries and need to have speed variable at which they are shifting around the court. Does anyone have a similar laboratory study with which to help me?
Thanks in advance
I'm interested in this product by XSens for sports kinematics analysis, and I'm looking for feedback from users of this system in a context of biomechanical research :
I'm aware that inertial systems are prone to serious limitations compared to optical motion capture, including positional drift and magnetic disturbance. Do we have to (re)calibrate (too) often ?
Moreover, I guess it is not trivial to transfer from the XSens "functional axes" to true anatomical axes ?
And finally, what are your experience with the new wireless XSens Awinda system ? Do you experience instabilities or dropouts during the acquisitions ?
Thank you very much
i have a clubfoot model and a corrective orthosis (special shoe) model i designed. i want to simulate the deformation of the foot due to the forces that act on it while its inside this orthosis.