Dynamics of Aimed Mid-air Movements

Mid-air arm movements are ubiquitous in VR, AR, and gestural interfaces. While mouse movements have received some attention, the dynamics of mid-air movements are understudied in HCI. In this paper we present an exploratory analysis of the dynamics of aimed mid-air movements. We explore the 3rd order lag (3OL) and existing 2nd order lag (2OL) models for modeling these dynamics. For a majority of movements the 3OL model captures mid-air dynamics better, in particular acceleration. The models can effectively predict the complete time series of position, velocity and acceleration of aimed movements given an initial state and a target using three (2OL) or four (3OL) free parameters.