Learning and Planning Based on Merged Experience from Multiple Situations for a Service Robot

• Main Authors: Zhixian Chen, Baoliang Zhao, Shijia Zhao, Ying Hu, Jianwei Zhang
• Format: Article
• Language: English
• Published: MDPI AG 2018-10-01
• Series: Applied Sciences
• Subjects: task knowledge; activity schema; HTN planning; experiences merging; abstract method
• Online Access: http://www.mdpi.com/2076-3417/8/10/1832

For a service robot, learning appropriate behaviours to acquire task knowledge and deliberation in various situations is essential, but the existing methods do not support merging the plan-based activity experiences from multiple situations in the same task. In this paper, an abstract method is introduced to integrate the empirical activity schemas of multiple situations, and a novel algorithm is presented to learn activity schema with abstract methods. Furthermore, a novel planner called the schema-based optimized planner (SBOP) is developed based on the learned activity schema, in which actions merging optimization and partially backtracking techniques are adopted. A simulation with a PR2 robot and a physical experiment is conducted to validate the proposed method. The results show that the robot can generate a plan to recover from failure automatically using the novel learning and planning method, given that the experienced exception has been merged in the activity schema. Owing to the improved autonomy, the proposed SBOP exhibits increased efficiency in dealing with tasks containing loops and multiple activity schema instances. This research presents a novel solution of how to merge activity experiences from multiple situations and generate an intelligent and efficient plan that could adapt to a dynamically changing environment.