Science topic

Human Movement Science - Science topic

Explore the latest questions and answers in Human Movement Science, and find Human Movement Science experts.
Questions related to Human Movement Science
  • asked a question related to Human Movement Science
Question
2 answers
Hello All
I'm trying to synchronize imu sensor with the Motion Capture system. Is this possible? If so, how?
thanks for answering
Alireza
Relevant answer
Answer
Hi Alireza,
First, what is the type of motion capture system do you have? Most of them actually have their own synchronization box, which serve as trigger in or trigger out for other external device including IMU. However, if your IMU sensor is a standalone sensor without any base to connected, then you can try an option to synchronize it by using some movement that cause spike on IMU signal like jumping.
Hope this helps you
  • asked a question related to Human Movement Science
Question
19 answers
N.B I do not want to use flight time to calculate jump height as this does not take into account the centre of mass of the individual
Relevant answer
Answer
I share
  • asked a question related to Human Movement Science
Question
2 answers
What is the best wall color of the lab to use with a IR cameras MoCap system (Qualisys, Vicon, Optitrack...)? We have always used white walls, without any problems. I read that blue color is the best option to use with the IR systems/spectrum. What is your opinion? Any color in particular? (please add pantone-color number)
Thanks
Best,
Jose Heredia-Jimenez Human Behavior & Motion Analysis Lab. HubemaLab. University of Granada in Ceuta.
Relevant answer
Answer
Thank you for the answer Dr. Jokstad
Best,
Jose Heredia-Jimenez
  • asked a question related to Human Movement Science
Question
1 answer
patellar reflex movement dataset which has displacement data of leg and foot which recorded by motion capture or collected in other ways
Relevant answer
Answer
Interesting. Look at propioceptive aspects
  • asked a question related to Human Movement Science
Question
6 answers
I'm going to examine the relation between the the surface electromyography (sEMG) signals and the arm movements. I have a large number of sEMG signals acquired simultaneously with a large number of human arm joint angles during different movements. Those signals were recorded from forearm and upper-arm muscles. I need to select from those sEMG a subset that contains the most informative channels representing those movements, i.e., I need to exclude the noisy signals from the analysis. So, rather than the visual inspection of the sEMG with the angle signals, is there a method to accomplish this goal? I know there are dimensionality reduction techniques, like the PCA, but I have to avoid this approach.
Relevant answer
Answer
Hi Mohammad,
after knowing your experiment now more in detail i would try to evaluate the suitability of each channel by checking the reproducibility of RMS signal during the movement that was carry out. To that end you could segment each channel in 6 epochs, each of them once reflecting the movement. A good channel should have a high correlation between all epochs.
Good channels also should show a close relation to the DOF siganl. however, in that case you should be careful which measure you use to quantify the relation. E.g. Pearson's correlation only assesses linear relations which may not exist in your case.
Greetings, Sebastian
  • asked a question related to Human Movement Science
Question
1 answer
I plan a study with a measurement of pressure firmness. Is there someone with experience with such a device?
Relevant answer
Answer
A lot of work on validating the Myoton has been carried out by Prof Maria Stokes and her team at Southampton Univesity - http://www.southampton.ac.uk/healthsciences/about/staff/mjs2.page
  • asked a question related to Human Movement Science
Question
4 answers
I'm looking for studies that proves a relation between kinetic chains' training and increasing performance in synchronized swimming for my degree's thesis.
I'm looking about proprioceptive capacities and training methods for the stabilization of chains in the right position, too. 
Relevant answer
Answer
Stephen, Michael Turvey's work is amazing, thank you to showing it to me. Thanks Jan, i will look in that direction and thank you Hamdy Elsaid abd elhamed Elnawasry for your helpful articles.
  • asked a question related to Human Movement Science
Question
6 answers
SRT = only one stimulus and one response
CRT = more than one stimulus to respond to and each stimulus has a specific response attached to it
DRT = more than one stimulus, but only one response to one specific stimulus with other stimulus requiring no response
Relevant answer
Dear Baseler,
We had used the Inquisit Mile Seconds. http://www.millisecond.com/
Is possible to find all kind of tests that you are needing in the library and modify according to your needs.
  • asked a question related to Human Movement Science
Question
6 answers
In the last decade, the concepts of many sciences were varied according the new studies that depend on the measurement tools, and the desired aims.
Relevant answer
Answer
Dear Abdel-Rahman,
I'd go along pretty much with Marcelo's answer.
As I see it, there is neither a clear-cut definition of kinesiology at an international level, nor is there a clear distinction to be drawn between what people understand by kinesiology as compared to human movement science(s). 
This pretty much depends on national traditions in terminology as well as  college structures. In Poland,  the Scandinavian and the Benelux-countries, kinesiology seems to have a tradition at least terminologically,  while in the German-speaking countries the term is used rather seldom as a designator for college disciplines. In the English-speaking countries, to my feeling it is pretty mixed - you should stick to the syllabus on the respective college homepage if you really want to know what's being taught there, when you read "kinesiology", "human movement studies", "motor learning and control", etc.,. Here, as in Scandinavia, there are close relations to physiotherapy, which, contrary to this,  in a lot of other nations is not considered a scientific field taught at an university, but is rather understood as a field of vocational training.
And when you compare, e.g., journals like "Journal of Human Movement Science" and "Journal of Human Kinetics", you'll find that they both cover a real broad area of scientific enterprise related to the  human motor system (biomechanical, physiological, neurological), to motor learning, motor development, motor control, and to various more or less applied areas associated thereto.
So, no, there won't be a conscise definition that applies for more than one national system or even university.
Regards,
Klaus Blischke
  • asked a question related to Human Movement Science
Question
4 answers
I'm questioning about the accuracy of infra-red devices...
Relevant answer
Answer
Thank you very much Hamdy!
  • asked a question related to Human Movement Science
Question
9 answers
I am a rugby player, I find difficulties when I want to side step my opponents and also I am not able to pass the ball in a particular space we my teammate can intercept the ball without slowing his movement. 
Relevant answer
Answer
Speed and Distance are related to accuracy as well as if the skill is a Simple to Complex skill and if it is in an Open or Closed Enviorment also weather effects and shoe surface interaction effects also play and effect as well as the skill of the opponent and/or teammate.  Thus, if one starts practicing the skill in a slow, smaller distance, closed environment with min. to no distractions, then moves into a faster greater distance and involve a more complex scenario and practice, practice in a blocked and random practice manner, the skill of passing and cutting should improve. I hope this helps.
  • asked a question related to Human Movement Science
Question
5 answers
A subject performs arm movements in a self-paced manner. Movement parameters are captured by sensors and data is streamed in real-time to the computer. There is a fair amount of variability in the sensors readings: in the attached figure, data points captured from 3 sensors during execution of 10 repetitions of 2 types of movement are shown in the attached file.
A couple of important points:
1) In regards to training data: many subjects will be performing the same types of movements, in slightly different ways. Given the small number of repetitions that each subject will be contributing for each class (say, around 10), we want to take advantage of across-subject structure.
2) In regards to classification: Classification needs to happen in "real time", i.e. while data is streamed. We can assume a typical movement duration (say, 5 seconds) to define a "page size" of data to use for the classification, but that can be pretty variable, both within and across subjects. Ideally, the classifier will return a class more frequently, e..g once per second; obviously, at the beginning of a new movement there will be large uncertainty about the class, which will be getting smaller as more data is streamed.
Relevant answer
Answer
Dear Stavros, thank you for your time.
I proposed the method  during my Phd Thesis, I was concerned on the generality and soundness  of the method more than ever. But I personally did apply it in realtime applications with success (in internal trials). For all the time my general aim was to create something usable in realtime. Not just a "scientific concept”.
But realtime is a fuzzy term, for it is “function” of the request. E.g. for a package shipping from NY to Washington, an hour for the delivery it is "real-time", is superfast. For an airbag sensor,  to react in less than 30 milliseconds means realtime. So, which  times of reactions are required?
For my realtime tests my rationale was speech recognition:  the method suggested to me by my former advisor Roberto Bisiani that worked for some years on realtime speech recognition matters, when he was a researcher and then professor at Carnegie Mellon University.
In speech recognition you divide a temporal acquisition in tiny  (circa 10 millisec) temporal slices and then you extract features  for (e.g.) HMM analysis. I do not use HMM, only my own method.
We are dipendent from Nyquist sample theorem: I used slices at regular rate of  ¾ sec (it was just a test, slide should be of different dimensions in my opinion).
I think  the methodology can be adapted to the time series for quasi-immediate reactions.
We could work together on the question, and eventually collaborate, at your ease, if you want.
I am reachable at pinardi@disco.unimib.it for any question.
My Best,
Stefano
  • asked a question related to Human Movement Science
Question
16 answers
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
Raúl
Relevant answer
Answer
Hi Raul,
In addition to using such cameras, one can also utilize an accelerometer together with the tracker to measure speed and change in direction.
You can then also download and use the simple free software of Kinovea to see the analysis that you want.
Hope this helps.
Regards,
Habib
  • asked a question related to Human Movement Science
Question
4 answers
I would like to show this to people outside the field to demonstrate what happen when body representations are altered. Preferably in English. Thank you
Relevant answer
  • asked a question related to Human Movement Science
Question
3 answers
The optical angle (Tau) changes as a function of the distance to an object (Tau = invtan(ObjectSize / distance). It is argued that when regulating distance it is a common strategy to null the change in Tau (Tau dot).
I am trying to find evidence for this theory in cyclical backwards and forwards human-avatar locomotion. However, when analyzing Tau dot there is a problem, as due to the 'tangential' relationship between Tau and the distance to an object, the rate of change for a deviation of 1 meter is more when the object is close compared to far away. Moreover, a deviation of 1 meter closer to the object results in a bigger rate of change than a deviation of 1 meter away from the object. This results into a bias for using Tau dot to quantify success in distance keeping. How can I normalize tau dot so that it is not sensitive to the distance the object is perceived from?
(I've tried tau / tau dot, but that doesn't seem to work..)
Thanks for any suggestions!
Relevant answer
Answer
The ratio of rate of change of angle over angular size could perhaps do the job. Note that this ratio corresponds to the inverse of time-to-contact. Making this connection might lead you to choose another greek-alphabet letter to designate optical size: Since the seminal work of Lee (Perception, 1976), in the perception-action literature tau is generally associated with optical information about time-to-contact and its rate of change over time, tau-dot, with information about the sufficiency of current deceleration to avoid collision.
  • asked a question related to Human Movement Science
Question
2 answers
My project is based on compression of body sensor data. It's main objective is to conserve energy during transmission. Hence, the data should be continuously monitored from a person wearing sensors and performing normal routine. If anyone knows where to find such data, please help.
Relevant answer
Answer
There is a new project (The Voice of the Body) from Samsung that plans to give people access to a large database of recorded movements. You can find more details on their website: http://www.voiceofthebody.io/bioinformatics
It's not available yet, but I think that may be a good option for what you want.
  • asked a question related to Human Movement Science
Question
5 answers
First of all, I want to know this value for the gastrocnemius and soleus muscles.
Relevant answer
Answer
Vladimir Zatsiorsky is completely right in stating that in eccentric contractions dF/dt can be very fast. Mind that a muscle is composed of a contractile and an elastic element in series. For fast eccentric actions dF/dt = dF/dx . dx/dt = k.dx/dt in which k is the elastic stiffness, thus dF/dt mainly depends on the lengthening speed dx/dt, not on the muscle contractile properties.
For comparing muscle contractile properties, you may better use isometric actions. For this case you can find some formulas in my paper 'Muscle mechanics and neuromuscular control, J. Biomechanics 36:1031-1038 (2003) in Appendix 1.
  • asked a question related to Human Movement Science
Question
10 answers
As far as I know, there are some methods for this purpose, such as UCM, GEM, and TNC. However, because these methods are complex, please let me know, are there a more simple methods for this purpose?
Thanks in advance,
Esmaeel.
Relevant answer
Answer
Since you have a discrete task (if you consider the success of shooting as goal and the release position, orientation and velocity as body level states) the GEM will be the best approach. I agree with Klaus Blischke that the CR (correlation by randomization) approach introduced by Muller also will be a good choice. but the sensitivity analysis an generality of GEM makes it the best choice. maybe it seems a little complex but really it is not that complex. I re command you to take a look at recent paper of Joseph Cusumano and Jonathan Dingwell. " Movement variability near goal equivalent manifolds: Fluctuation, control, and model-based analysis". specially section 4.4, general experimental hypotheses. they are really interesting. although some of them are not testable for your task (like DFA analysis that needs quite large number of trials) you can give some help from engineering groups working on the subject in Iran. 
the UCM analysis will be easier to run. It is appropriate for analyzing the continues task of throwing too (in a identical initial position until the ball release moment). 
the more easier approach will be PCA which you can run in MATLAB with a single function like princomp.
Generally it depends on your hypotheses and  level of analysis and interpretation you want to have. 
  • asked a question related to Human Movement Science
Question
2 answers
I know that the HKB model is applicable for bimanual coordination tasks like waggling two fingers or limbs within or between persons. I am curious if there is an extension of the HKB model, or another model, that would be relevant for coordination between more than two oscillators (e.g., typing, playing piano)?
Relevant answer
Answer
This seems relevant to what I am trying to ask. Thank you!
  • asked a question related to Human Movement Science
Question
3 answers
I'm looking for a bibliography about how body segments change their outer shape in motion. Trying the obvious keywords in different search engines and scientific databases basically lead me to works about (a) markerless motion capture, (b) analysis of silhouettes, and (c) face morphing. I'm more interested in the shape of other parts like upper or lower limbs.
Relevant answer
Answer
Thanks Matteo, but what I am looking for are references about characterisation of body shapes in motion, whereas the problem addressed in papers like the one you cite is rather the opposite: how to cancel the motion of such soft structures to estimate the rigid motion of the underlying bones. Of course, one of the strategies for that is trying to model the motion of the muscles and skin, but that is not the focus.
  • asked a question related to Human Movement Science
Question
5 answers
I am looking for any experience or publication about how a coach can create a learning environment, in learning design, for exploiting self-organisation coordination tendencies that exist in human movement systems?
Relevant answer
Answer
Hi Behazd, take a look at this paper that I wrote. 
Best, 
Pedro.
  • asked a question related to Human Movement Science
Question
1 answer
In modeling biologic rhythmic actions as limit-cycles, it has been reported that a negative Duffing term (i.e. -x^3) represents decreasing of variability near reversal points (or softening spring). The question is what type of "variability" we mean here? Spatial? Temporal? Any other type?
How could it be proved or visualized based on Duffing equations or any other method that variability decreases near reversal points?
Relevant answer
Answer
Space-time, actually. You could, for example, see the influence of a x^3 term by creating a Hooke plot. That plot is position~aceleration. A completely straight lined plot means the oscillator (limit-cycle) reduces to a harmonic oscillator; one only with a linear stiffness term. On the other hand, a x^3 term means the angular frequency , or velocity if that's easier to imagine, in the cycle is not constant.
Now, the problem faced by your question is it's slightly under defined. Are you basing your question on an analytic model such as x"+b*x'+c*x+d*x^3=0 ? (Note this has no nonlinear damping. So it won't give you a limit cycle, per se, but a damped out cycle.). If you are, the variability means nothing because it's a noise free system. However, try simulating this an adding a Gaussian noise term ( I think), and then making the hooke plot. If there is less variability around the endpoint, this is I believe , as you might guess, due to a softening spring. This implies a slowing down as an endpoint is reached. This also predicts an increased deceleration in a Hooke plgot, which is where the 3rd order term comes from. See the Hooke plot I attached (it's my data): It is several cycles of a handheld pendulum being swung, with the average superimposed. Arrows are added to where the variability would be expected to start decreasing.
If you're familiar with Fitts' law, look up Mottet and Bootsma (1999) "Dynamics of goal-directed rhythmical aiming", I believe. They fit this type of model to movement data and give a good description.
P.s., I wrote this quickly, but if you have more questions (model fitting, etc...) let me know.
Good Luck:
Justin F.
  • asked a question related to Human Movement Science
Question
3 answers
for example :
the heel contact phase to the toe contact phase (the loading response phase) is ... percentage in the stance phase of running.What percentage?
the toe contact phase to the heel off phase (the midstance phase) is... percentage in the stance phase of running.What percentage?
the heel off phase to the toe off phase (push off phase) is ...percentage in the stance phase of running.What percentage?
Two foot switches are used to record the events running in my research.
please help me. thanks
Relevant answer
Answer
It depends on your running speed and some parameters. Novachek and Vaughan make some studies about that.
Regards
  • asked a question related to Human Movement Science
Question
3 answers
Since there are a lot of references in this field, I'd like to find one or a few references that define 'coordination' once and for all (if possible).
Relevant answer
Answer
Thank you Andrew for this nice review. Good list of articles.
  • asked a question related to Human Movement Science
Question
9 answers
For example, when we apply lateral horizontal 600 N on T7 , what happens to the loading on the lumbar joints?
Relevant answer
Answer
You might consider looking up "induced Acceleration Analysis" a method for assessing the effect of accelerations on one segment across other linked segments in a MS model.