Static Optimization without GRF

[shicheng wang]

Dear Experts,



The residual forces of the Pelvis (700N) are particularly large due to the lack of ground reaction forces that we have in the experiment. This also resulted in the RRA results needing to be altered by a large mass (-70kg). But we are only interested in the muscle strength of the lower limb (For example, bifemlh and bifemsh...).

So we want to lock the pelvic coordinates and add a large residual stress (Fx, Fy, Fz, Mx, My, Mz) to the actuator (Of course the force of the back-up actuator is very small), RRA and OS are then implemented to get the result. There are no bugs in the software and the RRA results obtained in this way are good, with very little mass to change.

But is this a meaningful way to gain muscle power? Or, is there any alternative to GRF, such as adding a seat?

Thanks a lot.



Kind regards,
Shicheng