Question about task observation

[qgallouedec]

Question about task observation

[qgallouedec]

In fact the actual observation that the agent receives the observation is composed of several components (in the form of dict).

observation = {
  "observation": ...,
  "desired_goal": ..., 
  "achieved_goal": ...,
}

• For the key "observation", there are two components:
  • the robot-related component (the position of the gripper, its speed etc.)
  • the task-related component (the position of the objects, the speed etc.)
• For the key "desired_goal", this is the goal of the task. For example, the target position of the object for the PickAndPlace task.
• For the key "achieved_goal", it is the goal achieved at time t. For example for PickAndPlace, it is the current position of the object.

Several remarks:

• The codes you attached are for building the task-related observation. This component is then concatenated with the component linked to the robot, then put in a dict with the desired goal and the achieved goal. (see above)
• "achieved_goal" is usually redundant with the components of the observation. For example, for PickAndPlace, the position of the object is in the observation vector and in the "achieved_goal" vector.
• For Reach, there is no component linked to the task because there is no object (in this case, the terminology is a bit misleading because there is still a task to perform, but this is a special case so we left it like that)

[qgallouedec]

All this is explained in the publication linked to panda-gym, I strongly advise you to read it (especially the diagram)