Provide easy-to-use, extensible software for modeling, simulating, controlling, and analyzing the neuromusculoskeletal system.
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Julian Atkinson
- Posts: 52
- Joined: Thu Feb 25, 2016 12:39 am
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by Julian Atkinson » Wed Nov 15, 2017 2:28 am
Hi there
I have plotted a comparison of the kinematics for IK vs RRA vs CMC.
I see a phase shift in the kinematics produced by RRA. Also, the kinematics from RRA is subsequently fed into CMC, but the CMC matched IK better than RRA.
Can anyone offer any insight as to why RRA has this phase shift around 65% of gait?
- j.jpg (189.5 KiB) Viewed 891 times
Thank you
regards,
Julian
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jimmy d
- Posts: 1375
- Joined: Thu Oct 04, 2007 11:51 pm
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by jimmy d » Tue Nov 21, 2017 3:10 pm
My first instinct seeing these plots is that it is a reporting issue. RRA uses a variable step size integrator so there is no guarantee that you will have the same number of frames as the input kinematics. For reporting, you will need to spline the rra kinematics to have linear rate.
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Julian Atkinson
- Posts: 52
- Joined: Thu Feb 25, 2016 12:39 am
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by Julian Atkinson » Thu Nov 23, 2017 2:30 am
Thank you for your response James.
The results of all three functions have been resampled for this figure. This was done using the interp1 function in matlab, with the 'pchip' setting which is a shape-preserving piecewise cubic interpolation.
regards,
Julian