static optimization with one force plate

[Park SangJun]

I want to do that and use the status file as an analysis tool to study knee joint contact force
Pipelines are as follows
Scaling
IK
static optimization
Analytical knee contact force
There are static test trc files for scaling, trc files for moving the sedentary stand, and grf force files for the right foot, so the external force applied to the left foot and hip when moving the sedentary stand is unknown
When I think of ID, even without the external force of the left foot and hip, if there is GRF data of the right foot, I think we can calculate the exact value for the knee and ankle of the right foot
Similarly, even without the left foot GRF and external force in the hip, you can put the status file obtained through static optimization into the analysis to achieve the correct right knee joint contact

[Mohammadreza Rezaie]

Hi, if I understand correctly, you are asking about whether the pipeline is ok when there is only one force plate.
Yes, that's totally fine, and the outputs of ID, SO, and JR of the leg the GRF has been applied to are still valid.
Hope this helps.

[Park SangJun]

Thank you!
Thank you for your response.
But I have a question.
Take the knee joint, for example,
When only the GRF of the right foot is taken as an input, the output of the left knee in the ID (moment) is garbage, but in the same situation for SO, there is the output that the knee joint flexor and extensor are activated symmetrically to the left and right side. Also, even if the knee joint contact force was calculated through analysis, the values of the left and right legs are symmetrical.
I think this result is not reasonable. Because I only provided the GRF data on the right, I think SO and Analysis should have garbage on the left leg like ID.
Which one is wrong in my opinion? If you think about SO, isn't it a situation where the person sitting on the stool trying to stand up while only the right leg works in the from where simulation stands?
and, when i performing SO, there is too high value of violation.
GRF of only right foot is the reason of that high violation?