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fjandrad / CartesioTests

Attempts to get a deeper understanding of the xbot/opensot/cartesio framework
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Doubts about force constraints #1

Open fjandrad opened 3 years ago

fjandrad commented 3 years ago

This is the repo I mentioned in the last email over a month ago. I am coming back to this to see if I can figure out ( with your help ) how to develop the custom tasks we need, but more importantly get the required understanding to keep using this for more custom cases.

@alaurenzi @enricoMingo

I am trying to use the Normal torque constraint. In general, in many of the code found in the force folder there is this use of an affine helper. I can not seem to find any documentation about it and I only have access to header files.

Installation done with the file nightly/xbot2-full-devel/xenial-nightly.tar.gz . With default installation the file I am aiming to use can be found in xbot/include/OpenSoT/constraints/force

fjandrad commented 3 years ago

@alaurenzi do you happen to have some examples using wrenches?

alaurenzi commented 3 years ago

Hi @fjandrad, sorry to come back to you after a long time I suggest to start with some concrete (and simple) control problem for your robot. Maybe an inverse dynamics controller where we optimize over joint acceleration and contact forces can be an option (since you mention wrenches).

To this aim, I suggest you try to (i) start from a pure kinematics stack file as explained here or following the coman example (inside roscd cartesian_interface/examples/configs/) that you can test via interactive markers (see mon launch cartesian_interface coman.launch), (ii) switch tasks to the acceleration-based formulation of cartesio_acceleration_support, (iii) add force variables and link them to the acceleration via a DynamicFeasibility constraint, (iv) add constraints on forces (e.g. friction).

Later on, we can work to expand the framework with additional tasks and constraints