GaCIT in Tampere, day 3.

In the morning Howell Istance of De Montford University, currently at University of Tampere, gave a very intersting lecture concerning gaze interaction, it was divided into three parts 1) games 2) mobile devices 3) stereoscopic displays

Games
This is an area for gaze interaction which have a high potential and since the gaming industry has grown to be a hugh industy it may help to make eye trackers accessible/affordable. The development would be benificial for users with motor impairments. A couple of examples for implementations were then introduced. The first one was a first person shoother running on a XBOX360:
The experimental setup evaluation contained 10 repeated trials to look at learning (6 subjects). Three different configurations were used 1) gamepad controller moving and aiming (no gaze) 2) gamepad controller moving and gaze aiming and 3) gamepad controller moving forward only, gaze aiming and steering of the movement.
Results:
However, twice as many shots were fired that missed in the gaze condition which can be described as a "machine gun" approach. Noteworthy is that no filtering was applied to the gaze position.
Howell have conducted a analysis of common tasks in gaming, below is a representation of the amount of actions in the Guild Wars game. The two bars indicate 1) novices and 2) experienced users.

Controlling all of these different actions requires switching of task mode. This is very challenging considering only on input modality (gaze) with no method of "clicking".

There are several ways a gaze interface can be constructed. From a bottom up approach. First the position of gaze can be used to emulate the mouse cursor (on a system level) Second, a transparent overlay can be placed on top of the application. Third, a specific gaze interface can be developed (which has been my own approach) This requires a modification of the original application which is not always possible.

The Snap/Clutch interaction method developed by Stephen Vickers who is working with Howell operates on the system level to emulate the mouse. This allows for specific gaze gestures to be interpretated which is used to switch mode. For example a quick glace to the left of the screen will activate a left mouse button click mode. When a eye fixation is detected in a specific region a left mouse click will be issued to that area.

When this is applied to games such as World of Warcraft (demo) specific regions of the screen can be used to issue movement actions towards that direction. The image below illustrates these regions overlaid on the screen. When a fixation is issued in the A region an action to move towards that direction is issued to the game it self.

Stephen Vickers gaze driven World of Warcraft interface.

After lunch we had a hands-on session with the Snap/Clutch interaction method where eight Tobii eye trackers were used for a round multiplayer of WoW! Very different from a traditional mouse/keyboard setup and takes some time to get used to.

• Istance, H.O.,Bates, R., Hyrskykari, A. and Vickers, S. Snap Clutch, a Moded Approach to Solving the Midas Touch Problem. Proceedings of the 2008 symposium on Eye Tracking Research & Applications; ETRA 2008. Savannah, GA. 26th-28th March 2008. Download

• Bates, R., Istance, H.O., and Vickers, S. Gaze Interaction with Virtual On-Line Communities: Levelling the Playing Field for Disabled Users. Proceedings of the 4th Cambridge Workshop on Universal Access and Assistive Technology; CWUAAT 2008. University of Cambridge, 13th-16th April 2008. Download

The second part of the lecture concerned gaze interaction for mobile phones. This allows for ubiquitous computing where the eye tracker is integrated with a wearable display. As a new field it is surrounded with certain issues (stability, processing power, variation in lightning etc.) but all of which will be solved over time. The big question is what the "killer-application" will be. ( entertainment?) A researcher from Nokia attended the lecture and introduced a prototype system. Luckily I had the chance to visit their research department the following day to get a hands-on with their head mounted display with a integrated eye tracker (more on this in another post)

The third part was about stereoscopic displays which adds a third dimension (depth) to the traditional X and Y axis. There are several projects around the world working towards making this everyday reality. However, tracking the depth of gaze fixation is limited. The vergence (as seen by the distance between both pupils) eye movements are hard to measure when the distance to objects move above two meters.

Calculating convergence angles
d = 100 cm tan θ = 3.3 / 100; θ = 1.89 deg.
d = 200 cm tan θ = 3.3 / 200; θ = 0.96 deg.


Related papers on stereoscopic eye tracking:

• Essig, K., Pomplun, M. & Ritter, H. (2006). A neural network for 3D gaze recording with binocular eye trackers. International Journal of Parallel, Emergent, and Distributed Systems, 21 (2), 79-95.

• Y-M Kwon, K-W Jeon, J Ki, Q M. Shahab, S Jo and S-K Kim (2006). 3D Gaze Estimation and Interaction to Stereo Display The International Journal of Virtual Reality, 5(3):41-45

The afternoon was spent with a guided tour around Tampere followed by a splendid dinner at a "viking" themed restaurant.

Eye Gaze Interactive Air Traffic Controllers workstation (P.Esser & T.J.J Bos, 2007)

P.Esser and T.J.J Bos at the Maastricht University have developed a prototype for reducing the repetitive strain injuries Air Traffic Controllers sustain while operating their systems. The research was conducted at the National Aerospace Laboratory in the Netherlands. The results indicate a clear advantage compared to the traditional roller/track ball, especially for large distances. This is expected since Fitt's law does not apply in the same manner for eye movement as physical limb/hand movement. Sure eye movement over longer distances takes more time to perform than short ones but it does not compare to moving you arm one inch vs. one meter. Certainly there are more applications that could benifit from gaze assisted interaction, medical imaging in the field of radiology is one (such as CT, MRI, these produce very high resolution images with resolutions up to 4096x4096 pixels)

Summary of the thesis "Eye Gaze Interactive ACT workstation"
"Ongoing research is devoted to finding ways to improve performance and reduce workload of Air Traffic Controllers (ATCos) because their task is critical to the safe and efficient flow of air traffic. A new intuitive input method, known as eye gaze interaction, was expected to reduce the work- and task load imposed on the controllers by facilitating the interaction between the human and the ATC workstation. In turn, this may improve performance because the freed mental resources can be devoted to more critical aspects of the job, such as strategic planning. The objective of this Master thesis research was to explore how human computer interaction (HCI) in the ATC task can be improved using eye gaze input techniques and whether this will reduce workload for ATCos.


In conclusion, the results of eye gaze interaction are very promising for selection of aircraft on a radar screen. For entering instructions it was less advantageous. This is explained by the fact that in the first task the interaction is more intuitive while the latter is more a conscious selection task. For application in work environments with large displays or multiple displays eye gaze interaction is considered very promising. "



Download paper as pdf

Hot Zone prototype (Wakaruru)

The following video demonstrates a prototype of the Hot Zone system for controling windows applications. Call out the Hot Zone are made by pressing a single Hotkey and blink. The menu can be closed by looking outside the zone and blinking. Submitted to YouTube by "Wakaruru"

Submitted to YouTube by "Wakaruru"

The second video demonstrates how Hot Zone could be used to work with real world applications (PowerPoint). The center of the zone is located at the current gaze position when it's call out (like a context menu). the commands in the five zones depend on current selected object (based on what you are looking at now). No mouse needed (the cursor was designated as the gaze position using API). Pure blink without hotkey pressed was designated as single mouse click. Thus blink on the text area start text editing. Keyboard is only used for typing and hotkey to call out the zone. The eye tracking device used is ASL EH6000.

Submitted to YouTube by "Wakaruru"

Gaze Interaction Demo (Powerwall@Konstanz Uni.)

During the last few years quite a few wall sized displays have been used for novel interaction methods. Not seldomly these have been used with multi-touch, such as the Jeff Han´s FTIR technology. This is the first demonstration I have seen where eye tracking is used for a similar purpose. A German Ph.D candidate, Jo Bieg, is working on this out of the HCI department at the University of Konstanz. The Powerwall is 5.20 x 2.15M and has a resolution of 4640 x 1920.

The demonstration can be view at a better quality (10Mb)

Also make sure to check out the 360 deg. Globorama display demonstration. It does not use eye tracking for interaction but a laser pointer. Nevertheless, really cool immersive experience, especially the Google Earth zoom in to 360 panoramas.

Inspiration: Looking my Way through the Menu: The Impact of Menu Design and Multimodal Input on Gaze-based Menu Selection

As discussed earlier in my blog the differences between gaze vs mouse based interaction calls for interfaces that are especially designed for the purpose. A group of German researchers present a novel approach based on a radial menu layout. The work has been carried out by Yvonne Kammerer and Katharina Scheiter both at the Knowledge Media Research Center, University of Tuebingen in conjunction with Wolfgang Beinhauer at the Fraunhofer Institute for Industrial Engineering, Stuttgart.

My own prototype contains U.I elements that are based on the same on the style of interaction. However, this work goes further towards a multi-level menu system while my component is aiming more for a quick one-level saccade selection. The advantages of the radial layout in a gaze based menu component is discussed in this paper. Interesting concept, looking forward to the presentation at the SWAET2008 conference.

Abstract
"In this paper a study is reported, which investigates the effectiveness of two approaches to improving gaze-based interaction for realistic and complex menu selection tasks. The first approach focuses on identifying menu designs for hierarchical menus that are particularly suitable for gaze-based interaction, whereas the second approach is based on the idea of combining gaze-based interaction with speech as a second input modality. In an experiment with 40 participants the impact of menu design, input device, and navigation complexity on accuracy and completion time in a menu selection task as well as on user satisfaction were investigated. The results concerning both objective task performance and subjective ratings confirmed our expectations in that a semi-circle menu was better suited for gaze-based menu selection than either a linear or a full-circle menu. Contrary to our expectations, an input device solely based on eye gazes turned out to be superior to the combined gaze- and speech-based device. Moreover, the drawbacks of a less suitable menu design (i.e., of a linear menu or a full-circle menu) as well as of the multimodal input device particularly obstructed performance in the case of more complex navigational tasks." Download paper as pdf.