Very interesting info, thanks for that. I believe with my current knowledge and experience, I will have to stick to the marker-sets provided and included on the vendor software. As I get more experience, I will most likely move into more sophisticated systems and analysis.

Quote Originally Posted by msingh27 View Post
I have not seen this system, so not qualified to comment. But, it seems to be Optical passive marker system, so should have same capabilities and features as any other system of comparable technical specifications. Some desirable features in available software are:
1- Support for Custom, as well as standard maker sets, such as Standard Gait, Helen Hayes & Cleveland Clinic, Plug-in-Gait,IOR etc. and also 6DOF as well as Hybrid.
2- Defining virtual markers and segments.
Functional Joint center computations.

Reason for having these features in Passive marker Motion Capture system software is that in Passive markers systems, markers do not have any distinct ID. System has marker labeling errors due to many reasons, such as occlusion(specific marker going out of sight for some frames during session), marker swapping, IR noise etc.. Marker-sets help system correct those errors automatically, based on joint constraints based on specific model definition corresponding to marker-set.

You can ofcourse capture raw marker data , if particular marker-set for third party softwares (like OpenSIM) is not available in Motion Capture System Software, but in the absence of additional information, like model definition, system's marker labeling errors will amplify. That will invariably involve manual data cleaning, that can be extensive.

Alternative is to capture according to one of the marker-sets available in Motion Capture System software and then map marker positions as per marker-set of external software. But, this too will require manual efforts and errors in marker measurements will multiply.

If you are OK with modelling and analysis capabilities (marker-sets, protocols, reporting) offered by Motion Capture System software, none of his matters. But, there are continuous research efforts in standardization of marker-set for different applications, especially Gait, to increase reliability and consistency of results. There can be errors due to variation in application of markers in-between clinicians and in-between subjects/trials by the same clinician.