Optimised Learning from Demonstrations for Collaborative Robots

Yuqi Wang, Yudie Hu, Shirine El Zaatari, Weidong Li, Yong Zhou

Research output: Contribution to journalArticlepeer-review

Abstract

The approach of Learning from Demonstrations (LfD) can support human operators especially those without much programming experience to control a collaborative robot (cobot) in an intuitive and convenient means. Gaussian Mixture Model and Gaussian Mixture Regression (GMM and GMR) are useful tools for implementing such a LfD approach. However, well-performed GMM/GMR require a series of demonstrations without trembling and jerky features, which are challenging to achieve in actual environments. To address this issue, this paper presents a novel optimised approach to improve Gaussian clusters then further GMM/GMR so that LfD enabled cobots can carry out a variety of complex manufacturing tasks effectively. This research has three distinguishing innovative characteristics: 1) a Gaussian noise strategy is designed to scatter demonstrations with trembling and jerky features to better support the optimisation of GMM/GMR; 2) a Simulated Annealing-Reinforcement Learning (SA-RL) based optimisation algorithm is developed to refine the number of Gaussian clusters in eliminating potential under-/over-fitting issues on GMM/GMR; 3) a B-spline based cut-in algorithm is integrated with GMR to improve the adaptability of reproduced solutions for dynamic manufacturing tasks. To verify the approach, cases studies of pick-and-place tasks with different complexities were conducted. Experimental results and comparative analyses showed that this developed approach exhibited good performances in terms of computational efficiency, solution quality and adaptability.
Original languageEnglish
Article number102169
JournalRobotics and Computer-Integrated Manufacturing
Volume71
Early online date31 Mar 2021
DOIs
Publication statusE-pub ahead of print - 31 Mar 2021

Funder

National Natural Science Foundation of China (Project No. 51975444), and partially funded by the UK industrial and research partners (the Unipart Powertrain Application Ltd. (UK) and the Institute of Digital Engineering (UK)).

Keywords

  • Learning from Demonstrations
  • Gaussian Mixture Model
  • Collaborative Robots

Fingerprint Dive into the research topics of 'Optimised Learning from Demonstrations for Collaborative Robots'. Together they form a unique fingerprint.

Cite this