Are you working on Vicon nexus ?

Dear Mr Prakash,

Are you talking about a full gait analysis lab with 3D motion capture (for kinematics), forceplates (for dynamics), electromyography, etc..., or maybe only electronic walkway and/or video? Is it mainly a clinical gait lab or not?

The answers to your request (which material) will depend on your needs. Please give some more details. 

Regarding color background,

if you are using mocap system with passive markers (reflective), as Vicon system, better way is to try to reduce the reflectance value of your environment (i.e. laminate floor, walls), even if recent cameras and software allow to deal with reflectance. So a choice of matte color is surely better.

For the color itself, it depends your feelings. It only has to allow you to get a good color contrast for video quality purpose. You can look at usual choice of color in clinical settings and effect of colors on mood and behavior.

I hope this will help you in your thinking.

Best regards,

AG.

All surfaces should be matt finish. As for colour, it is not critical except dont use pure white or black. I would go for a neutral colour with minimal contrast changes throughout.

Sir you can visit some gait analysis laboratory and all depends upon over your need and effort.

thanks all for your valuable suggestion.

I am using 4 CAMSYS Video

Monitoring Packages from BIOPAC. but i am unable to decide what should be the proper position of cameras to get a 3D view of the  marker placed on subject body .. 

Dear Mr. Pakrash

The camera locations are dependent to the research purpose and how the researcher wants to acquire the data. Generally, according to winter’s suggestion the cameras lens angles should stay between 60 to 120 degrees in relation to each other. However if the research is performed unilaterally the camera can put in one side of capturing cube and angles between lenses could be applied as 60 degree. But if the research is performed bilaterally the cameras should be positioned in both side of the capturing cube which markers of both sides were seen by the cameras. Therefore the angle of 90 degree was appropriate for such purpose.  The height of the camera is depending on the cube height and the cube height is dependent to the highest height of the marker attach to your subject. In fact the height of the camera is depending on the maximum height of the marker within trials. The camera lens angle in respect to the ground or the cube surface is an important factor till the cameras don’t capture each other during trials.

As result of the lower number of cameras full body data acquisition is fallacious, because distance between cameras and the camera with the capturing cubes, result in marker loss in some frames and lower resolution. Eke, distance between capturing cube and the cameras is effective to the capturing frequencies and the accuracy of the resultant signals.

Best regards.

Alighanbari

Gait analysis Lab require many instruments, devices, and softwares. Such as EMG, 3D motion analysis, Treadmill, Force platform, Foot scan, and Static and dynamic balance system, etc...... 

Dear Chandra,

Please take a look at our website. http://codamotion.com/index.php/technology/clinical-gait-analysis

Codamotion is installed in many top gait labs around the world spanning CP, Stroke and Sports Rehab. Our system works in most lighting conditions and can be used in large and very small labs. We don't use camera technology, and our special 3D scanners can give large measurement volume from a small stand-off. Feel free to e-mail me if you need more info: [email protected]

Dear Chandra,

At the very least, you will need a 3D Motion Capture system. For that, you have 4 types of technologies to choose from. Optical-Passive Marker, Optical-Active Marker,Electromagnetic and Inertial-Gyro. Each Technology and products/models have their own features, strengths/weaknesses/limitations. Final choice will be driven by specific requirements/application and budgets. This will allow you to capture Motions of markers on body segments. For further reduction of these marker motions into meaningful Kinematics information like Joint angles, linear and angular velocities and accelerations, you will need to do Inverse Kinematics modeling and analysis.  You may want to develop you own human, articulated skeletal models using Software like Matlab. But that is a big task and unless your specific goal is to develop those models, it is not worth it. There are Software options available for these tasks, both free/open source and commercial.

Then, if you also want Body Dynamics computations (joint forces, torques, power), you are going to need on or more 6 component (forces and moments about X,Y,Z axes)Force Platforms or dual belt Instrumented Treadmill that could record Ground Reaction Forces form foot strike and do Inverse Dynamics modelling and analysis using synchronously recorded Motion Capture and GRF data.

Synchronously recorded EMG signals are also required to have idea about timing and extent of muscles/muscle groups activations that contribute to motions of specific joints of interest.

Synchronous data of dynamic Pressure distribution in contact surfaces of Shoes, Prosthetic Sockets is also important for O&P experts and Footwear designers.

Additional Video Cameras for synchronous reference video footage are also helpful. 

About background color, it maters if you are going to use passive marker optical Motion Capture system. Key point is that you should not have any surfaces that can reflect light containing IR into the cameras. These unwanted IR sources would produce noise in MoCap data. Grey color and surfaces (curtains, carpet) with matt textures are recommended.

Also, care should be taken to cutout outside light from entering the Lab. Although, nowadays Optical systems are available that can actively filter unwanted IR light to enable their use even in direct sunlight but it is always better to opt for prevention, rather than the cure.

We are Indian company specializing in providing and setting up Gait Analysis set ups and also training inverse kinematics/dynamics and also Forward dynamics modelling and analysis. We also provide consultancy on choosing the right components, depending on requirements, current and future, and budgets. Please contact me if you want to discuss about your application in details.

With so-called normal gait, but certain about what you want to measure. You may want to consider taking a look at force couples, biotensegrity mechanics, interchangeable oblique axis, kinetic loading and lateral sacral flexion.

November 16, 2016

Technical Report

Researchgate.com

DOI: 10.13140/RG.2.2.29972.50561

The Sacral X Axes; Location, Structure, Movement, Kinetic Loading, Function,

Biotensegrity Technology and Pathology. The essential pieces of the low back pain puzzle.

Richard L. DonTigny, PT

Independent researcher

[email protected]