IK tool error

[Jocelyn Hafer]

Hello,

I've been working with some gait data collected with APDM Opal v2 sensors and I have gotten through the data conversion and model calibration steps successfully using the Matlab code (I also was able to replicate the output for the example files provided online). With my data, I keep getting what looks like an optimization error when I run the inverse kinematics tool. I've tried testing different sections of my data or shorter data lengths to see if the solver is just getting stuck at a certain data point but the error is always the same (with the same error tolerance).

I've attached a screenshot of the error I'm seeing in Matlab, my original IMU data, setup files, and calibrated model. Any guidance would be greatly appreciated.

Thanks,
Jocelyn

error screenshot

Matlab_IK_error.jpg (134.36 KiB) Viewed 520 times

data.zip

data collected using APDM IMUs

(447.47 KiB) Downloaded 53 times

[Ayman Habib]

Hi Jocelyn,

The model you are using (leg39) is planar, so any out of plane motion will cause the solver to fail as you experienced. Please use a model that is capable of matching the orientations specified by your IMU data (or within tolerance).

Hope this helps,
-Ayman

[Jocelyn Hafer]

Hi Ayman,

Using a 3D model fixed the issue easily. Thanks!

-Jocelyn