My name is Ludwig Sidenmark. I'm a PhD student at Lancaster University.
And I'll present our research project, Radi-Eye.
This work is done in collaboration with Dominic Potts, Bill Bapisch, and Hans Gellersen.
Radi-Eye is a pop-up radial interface, designed to maximise expressiveness with input from only the eyes and head
and provides discrete and continuous input, and scaling to support larger feature sets.
I'll present its design and results for how it supports this type of interaction.
Gaze and head are attractive hands-free alternatives, as sensing is directly integrated into the HMD.
Gaze is fast and effortless, while head movement is more precise for control. However,
both lack an explicit selection mechanism and expose Midas touch issues as they are “always-on”.
Hands-free interfaces have therefore remained limited in their expressiveness and control.
For the design of Radi-Eye, we built on eye-head coordination insights.
Radi-Eye's core concept is to use an eye- and head-controlled interface
for expressive hands-free control of objects in any 3D environment. To achieve this, Radi-Eye
consists of three parts: The first part is a pop-up radial interface.
Its radial structure is based on the eyes and head's capability to move in all directions
when performing gaze shifts. The pop-up nature allows on-demand control without causing clutter
when not in use. The interface structure, position, and invocation
depend on its context of use. Object-dependent Radi-Eye interfaces are used to manipulate
specific objects and are invoked by singling out an object in the environment.
Alternatively, an Object-independent Radi-eye interface can interact with multiple objects
simultaneously or with objects that are not visible or at an uncomfortable head position.
These are invoked via a generic gesture or command.
The second part is Look & Cross, a gaze-activated head-crossing technique that employs gaze
for hover interaction, and head-crossing to select the gaze-activated widget.
This is natural and efficient for selection as head movement naturally follows eye gaze and avoids
Midas touch as the head remains typically offset from gaze.
Finally, Combining the radial pop-up interface and Look & Cross provides a broad set of widgets
available for object control. First, in addition to basic selection, Radi-Eye
also supports logically connected widgets such as checkboxes and radio buttons.
Second, extending Look & Cross provides continuous interaction by having the head cursor remain
within the widget boundary after selection. The interaction is then active until the head
cursor leaves the widget boundary, similar to holding down a button. We can also transform
the widget into a 1-dimensional slider along the ring arc by adding meaning to the cursor position.
Finally, Radi-Eye supports scaling in three ways to support larger interfaces and increased functionality.
First, nested interaction is supported by expanding the interface on outer rings.
Hidden nested widgets are displayed when gazing on the parent widget that can then be selected.
Second, the interface can replace widgets on a ring via toggling. Replacing widgets
allows a single ring to store a large number of widgets without relying on multiple layers.
Third, Radi-Eye allows fluid command composition for input of multiple parameters by placing
command options on separate rings. The user then selects a command at each ring when traversing
through the rings. The user may even pass over a ring without performing a selection
if a command is undesirable. We developed three VR and AR applications
to highlight Radi-Eye design considerations, of which you’ve now seen snippets of. Please
refer to the paper and the accompanying video figure for full design and application details.
Finally, we did a user study to see how radial properties such as menu size, widget amount,
and widget direction affected Look&Cross selection performance and preference.
From this study, there are two key points that I’d like to highlight:
One, users were able to quickly and accurately select Radi-Eye widgets.
Two, it is important to consider the natural behaviours of the eyes, head, and their coordination.
This includes: Selecting a comfortable menu size for the neck.
widget amount to assure easy selection without relying on straining refined movements.
Consider the direction of commonly used widgets as horizontal widgets were more comfortable
to select. Please refer to the paper for full study details.
So in conclusion: Combining gaze and head for interaction extends
their capabilities to allow effortless interface exploration and stable selection.
Together with Look & Cross, the radial interface provides discrete and continuous interaction
and multi-parameter input via command composition for expressive hands-free control.
Careful consideration of interface parameters has to be made to support easy interaction
that does not disturb natural gaze and head behaviours.
That is all for my talk, thank you for listening.