Poses should be independent of torso height

[jstnhuang]

If you teach the robot to do a wave while at the lowest height, and then raise the torso, the execution might fail because some poses are not reachable. Poses not associated with any landmarks should be defined relative to torso_lift_link instead of base_link.

[mbforbes]

It seems like there are multiple classes of these. Things like waves should be relative to torso_lift_link. But actions that happen on e.g. a flat surface, like brushing, but aren't relative to a landmark, should be relative to base_link. Those ones wouldn't work when the torso height is modified because you'd be leaving the surface (as opposed ones like waves which may or may not work because of unreachable poses). Really, the ones that happen on a surface like brushing are in fact relative to a landmark (the table), it's just not one that's used. (If I recall correctly, the table surface isn't treated as a landmark.)

[jstnhuang]

Good point. It seems like the table should be a landmark. However, we don't have the interface/algorithms to choose the appropriate landmark when the gripper is close to both the table and some objects. One solution that could solve both problems for now would be to encode the torso joint in the demonstration as well.