Human performance index – a generic performance indicator

Abstract

Human skill evaluation or human skill quantification in the original definition of a human adaptive mechatronics system is the main concern of this paper. However, a deficiency in terms of consistency and subjectivity makes human skill not fully indicative of actual human performance. That is, the term human skill can mean repeatability, adaptability, or learning capability depending on the aspects and systems of interest. This paper proposes a human performance index (HPI) concept to focus on human performance instead. The main contributions are the quantification of speed–accuracy characteristics based on Fitts’ classical speed–accuracy trade-off and the determination of human control strategy involved in completing a task. The experiment in this paper was conducted on a computer-based simple tracking system by using a computer mouse to follow a set of random circles on a display. Human operators were told to complete the task as quickly as possible. HPI values were then calculated with and without weightings on speed and accuracy criteria. Different human performance values reflect how human operators accomplish the same task under the same working conditions. These control strategies are associated with a degree of emphasis on the speed and accuracy characteristics of the operators’ control actions.