Add reference force updater

[rkoyama1623-2021]

@snozawa さんと相談しながら、ReferenceForceUpdaterというRTCを追加しました。

[k-okada]

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http://jenkins.jsk.imi.i.u-tokyo.ac.jp:8080/job/hrpsys-qnx/2597/
Test PASSed.

[haudren]

Hello,

It is always nice to see contributions !

However, I am a bit puzzled by this:

This component is a very simple RT component to learn how to develop.

If this is really the case, please refrain from adding unnecessary components to hrpsys-base as this package is deployed to robots and should not grow out of control (Similarly if you develop specialized components, they should probably go in their own package). If this is an error, please fix the issue: from what you propose in this pull request I can not fathom what is the use for this component because the ReferenceForceUpdater.txt is empty.

Cheers,
Hervé

[rkoyama1623-2021]

Sorry for the absence of document. I added the document about ReferenceForceUpdater.

ReferenceForceUpdater(rfu) helps biped robot keep balance in accordance with the forces applied on the arm end effectors.
The output of this component is modified reference force, which is input of AutoBalancer or ImpedanceController.
ReferenceForceUpdater modifies reference force so that reference force follows actual forces measured by sensors on arms' end effector.
AutoBalancer and ImpedanceController modifies joint angles, assuming that reference force is applied on end effecters.
Therefore ReferenceForceUpder is effective when you want to controll biped robot, based on actual force applied on end effectors.

regards,
koyama

[k-okada]

Refer to this link for build results (access rights to CI server needed):
http://jenkins.jsk.imi.i.u-tokyo.ac.jp:8080/job/hrpsys-qnx/2598/
Test PASSed.