The HPX online planning system employs the online Answer Set Programming solver oclingo to dynamically generate and repair plans while a robot is executing the plans. Due to its comparably low computational complexity in domains with many unknown contingencies, HPX is particularly well suited to perform failures diagnosis and dynamic plan repair in robotic environments. A beta version of HPX is currently in the testing phase and will be integrated in the ExpCog robotic framework.

The following video shows how the HPX planner is applied for Smart Home control in the Bremen Ambient Assisted Living Lab (BAALL). The BAALL is equipped with automatic doors, illumination control, adjustable furnitures and many more actuators and sensors. The auonomous wheelchair “Rolland” is designed to drive autonomously in narrow indoor environments.

The video illustrates a scenario where two autonomous wheelchairs can be used to bring a person to the bathroom. Once the goal is received and interpreted via speech recognition, the HPX system generates a plan, involving the first wheelchair to bring the person to the bathroom. However, an abnormality occurrs in that the passage of the wheelchair is blocked by the little box. This system failure is postdicted by the system and the plan is repaired. The new plan involves the other wheelchair driving to the person and bringing him to the bathroom.