simtk.org

Hi team,

First of all, the new version is doing great. Tracking results from CMC are remarkebly improved using version 2.4.0 compared to 2.2.1!

Second, I encountered some missin ginformation in written output files using the commend line and hope you'll help me out of this:

1. if I run RRA tool using the GUI recommended mass adjustments are shown in the message window. Using the command line, the written output file is identical to the output in the message window except of the recommended mass adjustments, which I am obviously interested in, while in version 2.2.1 the written output file did contain recommendations on mass adjustments.

2. I used to have a coordinate file containing ground reaction forces, as an input file besides the trc file in earlier version, so that the written ik.mot file also contains the ground reaction forces. In version 2.4.0 the resulting ik.mot file does not contain the ground reaction forces, only coordinates.

Can I somehow solve for this?

BR

Lydia

Hi Lydia,

Thanks for your feedback on the recent release.

1. Can you point me to the text that used to show (but not anymore).

2. In the past IK did "a favor" by copying other columns from input files to output files. While convenient this is not strictly a part of the IK solution process (it may have the drawback that you need to carry more files around). A more general approach would be to give generic tools that allow you to "combine" storage files to reduce the number of files that you need to carry around etc. If you explain your specific need (other than what data is in which files) then I'm sure we can help you out.

Best regards,
-Ayman

Hi Ayman,

Thanks for your quick reply.

1. Below is the text I am missing in the written output file and not in the message window
2. Having one motion file including both the joint kinematics and ground reaction forces enables to show the moving model simultaneously with the applied ground reaction forces in the GUI, this is actually what I need.


Loading external loads kinematics from file N:\Opensim\EMG2force\Subjects\ABA\walk2\IK\ABA_walk2_ik.mot ...
Storage: file=N:\Opensim\EMG2force\Subjects\ABA\walk2\IK\ABA_walk2_ik.mot (nr=90 nc=204)
Low-pass filtering external load kinematics with a cutoff frequency of 6...
Storage: file=N:\Opensim\EMG2force\Subjects\ABA\walk2\IK\ABA_walk2_ik.mot (nr=90 nc=204)

Note: requested COM adjustment time range 3.93 - 4.82 clamped to nearest available data times 3.93 - 4.82

Computing average residuals between 3.93 and 4.82
Average residuals before adjusting pelvis COM:
FX=0.363033 FY=5.99408 FZ=-0.780746
MX=3.08713 MY=0.662685 MZ=1.97045

CMCTool.adjustCOMToReduceResiduals:
pelvis weight = 107.557
dx=0.01832, dz=-0.0287022

dmass = -0.611226

Recommended mass adjustments:
ground: orig mass = 0, new mass = 0
pelvis: orig mass = 10.9678, new mass = 10.872
femur_r: orig mass = 8.6623, new mass = 8.58666
tibia_r: orig mass = 3.45276, new mass = 3.42261
talus_r: orig mass = 0.093129, new mass = 0.0923158
calcn_r: orig mass = 1.16411, new mass = 1.15395
toes_r: orig mass = 0.201717, new mass = 0.199956
femur_l: orig mass = 8.6623, new mass = 8.58666
tibia_l: orig mass = 3.45276, new mass = 3.42261
talus_l: orig mass = 0.093129, new mass = 0.0923158
calcn_l: orig mass = 1.16411, new mass = 1.15395
toes_l: orig mass = 0.201717, new mass = 0.199956
torso: orig mass = 31.8842, new mass = 31.6058

Computing average residuals between 3.93 and 4.82
Average residuals after adjusting pelvis COM:
FX=0.773516 FY=5.96292 FZ=-0.516662
MX=0.0334789 MY=0.764334 MZ=0.233814

Hi Lydia,

1. Looking at the code, I don't see why these messages are not output while others do, however you may try to set "use_verbose_printing" to "true" in the setup file for RRA and see if you get what you want.
2. For visualizing forces you can use the "File->Preview Motion Data" Option in the GUI, and then synchronize the motions to see the ground reaction forces in sync. with the motion.

Please let me know how that goes and best of luck,
-Ayman

Hi Ayman,

Unforunately, setting 'use_verbode_printing' to 'true' wasn't helpful. I will run RRA using the GUI.

The 'preview motion data' was what I was looking for to visualize the ground reaction force in sync with the motion. So, thanks for the advise.

Lydia