Task Roadmaps: Speeding up Task Replanning

Abstract

Modern industrial robots are increasingly deployed in dynamic environments, where unpredictable events are expected to impact the robot’s operation. Under these conditions, runtime task replanning is required to avoid failures and unnecessary stops, while keeping up productivity. Task replanning is a long-sighted complement to path replanning, which is mostly concerned with avoiding unexpected obstacles that can lead to potentially unsafe situations. This paper focuses on task replanning as a way to dynamically adjust the robot behaviour to the continuously evolving environment in which it is deployed. Analogously to probabilistic roadmaps used in path planning, we propose the concept of Task roadmaps as a method to replan tasks by leveraging an offline generated search space. A graph-based model of the robot application is converted to a task scheduling problem to be solved by a proposed Branch and Bound (B&B) approach and two benchmark approaches: Mixed Integer Linear Programming (MILP) and Planning Domain Definition Language (PDDL). The B&B approach is proposed to compute the task roadmap, which is then reused to replan for unforeseeable events. The optimality and efficiency of this replanning approach are demonstrated in a simulation-based experiment with a mobile manipulator in a kitting application. In this study, the proposed B&B Task Roadmap replanning approach is significantly faster than a MILP solver and a PDDL based planner.

Evaluation of the Rami 4.0 architecture course offered by the campus Manaus District Industrial of IFAM

“…These discoveries are both exciting and natural. They are natural because they are part of the consequences of any planned action that does not reach the fullness of its objectives, forcing the application of replanning (Guo et al, 2022;Di Lillo, Di Vito & Antonelli, 2022;Nash et al, 2022;Lager, Spampinato & Papadopoulos, 2022). They are interesting because they confirm that technical training focused on complex knowledge and skills, as is all Rami 4.0 content, often needs to change the teaching strategy's order.…”