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Joint angle assessment post and replies

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Angular velocity
Cintia França
2 Posts

Hello,

It is possible to use Tracker on the assessment of angular velocities? After setting a joint angle for analysis, it seems that the only data available is the respective angle and the angle of rotation as well. However, can the software give velocities?

Attached File: Capturadeecr20210128s11.21.21.png


Replies to Angular velocity

Re: Angular velocity -
Douglas Brown Avatar
Douglas Brown
339 Posts

The protractor does not produce angular velocity data, but perhaps it should!  In the meantime, you can get angular velocity from a point mass. You will have to put the origin at the vertex (elbow) and mark the point mass at the arm end (wrist). If you have already marked the elbow and wrist with point masses then this is easy: just set the coordinate system reference frame to the elbow (Coordinate System|Reference Frame menu).

In fact, as a general rule, the best way to use the protractor is to start by tracking each of the points of interest (e.g. elbow, wrist, shoulder) with a point mass. Then create the protractor and attach its vertex and ends to the point mass tracks. This gives you great freedom to measure whatever you want. You can also attach tape measures to point mass tracks, including particle models.

Hope this helps! Doug


> It is possible to use Tracker on the assessment
> of angular velocities? After setting a joint angle
> for analysis, it seems that the only data available
> is the respective angle and the angle of rotation
> as well. However, can the software give velocities?



Re: Angular velocity -
Cintia França
2 Posts

Many thanks Doug!

Best regards,

Cíntia França



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