Add joint ForceTorqueSensor

[mposa]

A feature request to add a new sensor type, similar to the wrist force/torque sensor on Atlas. The sensor would be attached a joint between two links. This will probably require compiling a smaller RBM that consists of the children of the joint and computing its inverse dynamics to back the external wrench. Care will have to be taken to add in contact and other constraint forces.

[RussTedrake]

This has become a high priority because we need it to simulate the force/torque sensors in the wrist of atlas, when the hands are attached.

[RussTedrake]

Twan points out that you could at least re-use the twist computations in the forward pass of the featherstone algorithm. When twan brings in his new kinematics code, this computation will all be done in doKinematics.

[gizatt]

Has there been any progress on this? This would be nice to have esp. now that we're thinking about the force/torque sensor on both the arm and Atlas

[sherm1]

@mposa: by ForceTorqueSensor do you mean obtaining the reaction force at a joint as described here?

[tri-ltyyu]

Use case is likely outdated. Closing for now. File new issue if needed.

[huihuaTRI]

The first step is to create a plan for this task.

[sherm1]

Fixed by #12123 -- reaction forces at joints can serve as force/torque sensors. Insert a fixed (weld) joint where the sensor should be, then use the MBP reaction forces output port to read out the forces and torques the weld is applying to hold things together.

[RussTedrake]

nice! might it be worth adding that idea to the documentation somehwere? so it would come up on a search? (wouldn't it be nice if doxygen provided that search...)

[sherm1]

Thanks, Russ -> issue #12790