cx_pddl_clips

Augment CLIPS-based reasoning with PDDL.

As PDDL is an expressive formalism, this module relies on an external pddl manager to do the heavy lifting.

Prerequisites

1. A running instance of the external pddl manager node
2. The RosMsgsPlugin
3. (for planning:) Generated CLIPS plugins cx::CXPDDLMsgsPlanTemporalPlugin and cx::CXPDDLMsgsTimedPlanActionPlugin
4. Open the respective ROS interfaces

Basic Usage

1. Store the information on the external node using a pddl-manager fact.
2. Load pddl instances using pddl-instance facts.
3. Maintain up-to-date information of a current situation modeled via pddl-fluent and pddl-numeric-fluent facts.
   • Fetch the initial situation using pddl-get-fluents and pddl-get-numeric-fluents facts.
   • Update the situation using pending-pddl-fluent and pending-pddl-numeric-fluent facts.
   • Add new objects using pending-pddl-object facts.
4. Specify desired future states through pddl goals
   • Describe goals using pddl-goal-fluent and pddl-goal-numeric-fluent facts.
   • Register the goal uisng the pddl-set-goals fact.
   • Clear goals using the pddl-clear-goals fact.
5. Obtain a viable plan using the pddl-planner-call fact.
   • Plans consist of pddl-action facts
6. Inspect actions to ensure smooth execution
   • Check whether an action is viable for execution by checking it’s precondition (start conditions).
   • Retrieve the projected effects.
   • TBD