Interacting with Touchless Gestures: Taxonomy and Requirements

Objective: The aim of this study is to make the taxonomy for classifying diverse touchless gestures and establish the design requirements that should be considered in determining suitable gestures during gesture-based interaction design. Background: Recently, the applicability of touchless gestures is more and more increasing as relevant technologies are being advanced. However, before touchless gestures are widely applied to various devices or systems, the understanding on human gestures' natures and their standardization should be prerequisite. Method: In this study, diverse gesture types in various literatures were collected and, based on those, a new taxonomy for classifying touchless gestures was proposed. And many gesture-based interaction design cases and studies were analyzed. Results: The proposed taxonomy consisted of two dimensions: shape (deictic, manipulative, semantic, or descriptive) and motion(static or dynamic). The case analysis based on the taxonomy showed that manipulative and dynamic gestures were widely applied. Conclusion: Four core requirements for valuable touchless gestures were intuitiveness, learnability, convenience and discriminability. Application: The gesture taxonomy can be applied to produce alternatives of applicable touchless gestures, and four design requirements can be used as the criteria for evaluating the alternatives.