Extending the Interaction Space of Rotary Knobs by Multi-touch-based Grasp Recognition
David M. Petersen, Edgar Gellert, Matthias Böhmer · 2023
Rotary knobs are widely used input devices for computers, household appliances, cars and other machinery. So far, their input capabilities are limited since the rotation of a knob only controls one single parameter. This paper presents the concept of a rotary knob that is capable of recognizing a user’s grasp for controlling different parameters, called MultiKnob. We contribute the hardware and software of a knob for detecting how many fingers are used when touching it. It uses IR light and FTIR-based multi-touch recognition. Within a target acquisition study, we used this new feature for allowing users to select the speed of a cursor for solving tasks. We found that users are able to leverage this novel device: Our 24 participants could make use of this new knob for being faster when moving a cursor into a target area compared to a fixed slow speed knob, and having less overshoots compared to a fixed fast speed knob. Further, we found that the MultiKnob gave rise to the strategy of changing grasp for switching from a fast and coarse-grained cursor movement to a slow and fine-grained cursor movement. We discuss different applications for using such a knob.