Feet movement in desktop 3D interaction

Abstract

In this paper we present an exploratory work on the use of foot movements to support fundamental 3D interaction tasks. Depth cameras such as the Microsoft Kinect are now able to track users' motion unobtrusively, making it possible to draw on the spatial context of gestures and movements to control 3D UIs. Whereas multitouch and mid-air hand gestures have been explored extensively for this purpose, little work has looked at how the same can be accomplished with the feet. We describe the interaction space of foot movements in a seated position and propose applications for such techniques in three-dimensional navigation, selection, manipulation and system control tasks in a 3D modelling context. We explore these applications in a user study and discuss the advantages and disadvantages of this modality for 3D UIs.

Interactions Under the Desk: A Characterisation of Foot Movements for Input in a Seated Position

“…In summary, (1) we built 1D and 2D ISO 9241-9 compliant movement time models for unconstrained foot pointing; (2) we found that unconstrained foot pointing is considerably slower than mouse pointing, but comparable to other input devices such as joysticks and touchpads; (3) we found no significant difference in performance between the dominant and non-dominant foot; (4) we found that left and right movement is easier than backwards and forwards; (5) the most comfortable movement for desktop foot interaction is heel rotation; (6) techniques that have a direct spatial mapping to the representation outperform the others; (7) when variables are shown separately, two feet work better than one; (8) we show that the feet perform similarly to the scroll wheel in tasks where the feet are used in conjunction with the mouse; and (9) we provide design guidelines and considerations based on our findings.…”

“…Sensing may be performed by conventional colour cameras [13], depth cameras [4,16], optical motion capture [18], audio [15] and smart floors [2].…”

“…Hoffman investigated unconstrained absolute positioning, but with users tapping on physical targets rather than using the foot for cursor control. However, modern devices that take input from the feet, such as depth cameras [4] and interactive floors [2] use absolute positioning, sometimes without physical proxies, making it important to study this kind of interaction.…”

“…To track the feet, we used an implementation of Simeone et al's tracker [4]. This system uses a Kinect sensor mounted under the desk and a MATLAB program that subtracts the background, converts the coordinate system from the camera plane to the floor plane, isolates the feet and fits ellipses to the remaining data.…”

“…Examples include the pedals in a car, musicians' guitar effect switches, and typists' use of transcription pedals. Recent technological advances renewed interest in foot-based input, be it for interacting with a touch-enabled floor [2], for hands-free operation of mobile devices [3], or for adding more input channels to complex tasks [4]. Despite this, we still lack a thorough understanding of the feet's capabilities for interacting in one of the most common computing setups-under the desk.…”