Operator Expertise in Bilateral Teleoperation: Performance, Manipulation, and Gaze Metrics

This paper presents a comprehensive user study aimed as assessing and differentiating operator expertise within bilateral teleoperation systems. The primary objective is to identify key performance metrics that effectively distinguish novice from expert users. Unlike prior approaches that focus primarily on psychological evaluations, this study emphasizes direct performance analysis across a range of telerobotic tasks. Ten participants (six novices and four experts) were assessed based on task completion time and difficulty, error rates, manipulator motion characteristics, gaze behaviour, and subjective feedback via questionnaires. The results show that experienced operators outperformed novices by completing tasks faster, making fewer errors, and demonstrating smoother manipulator control, as reflected by reduced jerks and higher spatial precision. Also, experts maintained consistent performance even as task complexity increased, whereas novices experienced a sharp decline, particularly at higher difficulty levels. Questionnaire responses further revealed that novices experienced higher mental and physical demands, especially in unfamiliar tasks, while experts demonstrated higher concentration and arousal levels. Additionally, the study introduces gaze transition entropy (GTE) and stationary gaze entropy (SGE) metrics to quantify visual attention strategies, with experts exhibiting more focused, goal-oriented gaze patterns, while novices showed more erratic and inefficient behaviour. These findings highlight both quantitative and qualitative measures as critical for evaluating operator performance and informing future teleoperation training programs.