title: Development of a frequency-separated knob with variable change rates by rotation speed.
abstract: The principle of frequency separation is a design method to display different information or feedback in accordance with the frequency of interaction between users and systems. This principle can be usefully applied to the design of knobs. Particularly, their rotation speed can be a meaningful criterion for applying the principle. Hence a knob can be developed, which shows change rates varying depending on its rotation speed. Such a knob would be more efficient than conventional knobs with constant change rate. We developed a prototype of frequency-separated knobs that has different combinations of the number of rotation speed steps and the size of the variation of change rate. With this prototype, we conducted an experiment to examine whether a speed frequency-separated knob enhances users' task performance. The results showed that the newly designed knob was effective in enhancing task performance, and that task efficiency was the best when its change rate increases exponentially and its rotation speed has three steps. We conducted another experiment to investigate how a more rapid exponential increase of change rate and a more number of steps of rotation speed influence users' task performance. The results showed that merely increasing both the size of the variation of change rates and the number of speed steps did not result in better task performance. Although two experimental results cannot easily be generalized to other contexts, they still offer practical information useful for designing a speed frequency-separated knob in various consumer electronics and control panels of industrial systems.
authors.affiliation: Department of Mechanical System Design Engineering, Seoul National University of Science & Technology, South Korea. Electronic address: huhnkim@seoultech.ac.kr.
authors.forename: Huhn
authors.initials: H
authors.lastname: Kim
authors.affiliation: Department of Industrial Engineering, Chonnam National University, South Korea. Electronic address: donghan.ham@gmail.com.
authors.forename: Dong-Han
authors.initials: DH
authors.lastname: Ham
mesh_terms: D004867:Equipment Design; D006804:Ergonomics; D005246:Feedback; D006801:Humans; D012399:Rotation; D014110:Touch
keywords: Control-display gain; Frequency separation principle; Speed frequency