Two days before my PhD defense, I found out that a manuscript that I submitted to ToCHI on unintended touch (aka palm rejection) was accepted for publication! The manuscript is entitled “Exploring and Understanding Unintended Touch during Direct Pen Interaction” (previously titled, “Is it Intended or Unintended? Palm Rejection during Direct Pen Interaction”) details a data collection experiment and an algorithmic analysis of various possible solutions to unintended touch on tablets. The work was part of the larger collection of pen-based work that I performed while I was an intern at Microsoft Research (yippee! for publication #4 from my MSR time).
An example of unintended touch information from the perspective of a digitizer. The current stylus location is denoted in blue and the unintentional touch events from the palm and little finger are denoted in varying shades of orange.
The manuscript will not be published until December 2014, so here is the abstract:
The user experience on tablets that support both touch and styli is less than ideal, due in large part to the problem of unintended touch or palm rejection. Devices are often unable to distinguish between intended touch, i.e., interaction on the screen intended for action, and unintended touch, i.e., incidental interaction from the palm, forearm, or fingers. This often results in stray ink strokes and accidental navigation, frustrating users. We present a data collection experiment where participants performed inking tasks, and where natural tablet and stylus behaviors were observed and analyzed from both digitizer and behavioral perspectives. An analysis and comparison of novel and existing unintended touch algorithms revealed that the use of stylus information can greatly reduce unintended touch. Our analysis also revealed many natural stylus behaviors that influence unintended touch, underscoring the importance of application and ecosystem demands, and providing many avenues for future research and technological advancement.
Yippee! Last week, I was honored to have my thesis accepted by, and successfully defended in front of my examining committee (consisting of the wonderful and fabulous, Dr. Walter F. Bischof, Dr. Pierre Boulanger, Dr. Brian Maraj, Dr. Paul Dietz, and Dr. Ken Hinckley). My defense ended up being a lot of fun, with many jokes and lots of laughter!
As my thesis won’t be released until November/December, I wanted to post my (very wordy) abstract below in the mean time. I’m super excited to be finished my PhD and am eagerly looking forward to my post-U of A days!
|Done and Printed!
Although pens and paper are pervasive in the analog world, their digital counterparts, styli and tablets, have yet to achieve the same adoption or frequency of use. Digital styli should provide a natural, intuitive method to take notes, annotate, and sketch, but have yet to reach their full potential. There has been surprisingly little research focused on understanding why inking experiences differ so vastly between analog and digital media and amongst various styli themselves. To enrich our knowledge on the stylus experience, this thesis contributes a foundational understanding of the factors implicated in the varied experiences found within the stylus ecosystem today.
The thesis first reports on an exploratory study utilizing traditional pen and paper and tablets and styli that observed quantitative and behavioural data, in addition to preferential opinions, to understand current inking experiences. The exploration uncovered the significant impact latency, unintended touch, and stylus accuracy have on the user experience, whilst also determining the increasing importance of stylus and device aesthetics and stroke beautification. The observed behavioural adaptations and quantitative measurements dictated the direction of the research presented herein.
A systematic approach was then taken to gather a deeper understanding of device latency and stylus accuracy. A series of experiments garnered insight into latency and accuracy, examining the underlying elements that result in the lackluster experiences found today. The results underscored the importance of visual feedback, user expectations, and perceptual limitations on user performance and satisfaction. The proposed Latency Perception Model has provided a cohesive understanding of touch- and pen-based latency perception, and a solid foundation upon which future explorations of latency can occur.
The thesis also presents an in-depth exploration of unintended touch. The data collection and analysis underscored the importance of stylus information and the use of additional data sources for solving unintended touch. The behavioral observations reemphasized the importance of designing devices and interfaces that support natural, fluid interaction and suggested hardware and software advancements necessary in the future. The commentary on the interaction – rejection dichotomy should be of great value to developers of unintended touch solutions along with designers of next-generation interaction techniques and styli.
The thesis then concludes with a commentary on the areas of the stylus ecosystem that would benefit from increased attention and focus in the years to come and future technological advancements that could present interesting challenges in the future.
Its now that wonderful time in my PhD life when I have finished writing my thesis, it has been passed on to the committee, and I are eagerly awaiting my defense! After many years of very hard work and some good planning on our part, my partner in crime (and life!!), Fraser, and I will receive our PhD degrees in November 2014! My thesis is a nice wrap up of all of the pen-based interaction that I have been publishing over the last year. I must say, I am super proud of myself. Fraser’s thesis is on gesture learning and I am super jealous that he gets to talk about LEGO and Disney’s Haunted Mansion in his dissertation!
We just couldn’t resist not getting Mickey Graduate Ears!
Rounding out today’s news is another Graphics Interface 2014 publication that I have forthcoming. This publication, “The Pen Is Mightier: Understanding Stylus Behaviour While Inking on Tablets” reports on a user study that was conducted at Microsoft Research during my extended internship. The study investigated the differences in hand posture, hand movements, writing size, and user preferences while participants were performing note-taking and sketching tasks using traditional pen and paper, a digital tablet with a passive stylus, and a digital tablet. Dr. Anoop Gutpa served as my Microsoft mentor during the project and Fraser and Walter assisted me with the analysis and discussion sections of the work. Once the full paper is available, I will provide a link to it.
Although pens and paper are pervasive in the analog world, their digital counterparts, styli and tablets, have yet to achieve the same adoption and frequency of use. To date, little research has identified why inking experiences differ so greatly between analog and digital media or quantified the varied experiences that exist with stylus-enabled tablets. By observing quantitative and behavioural data in addition to querying preferential opinions, the experimentation reaffirmed the significance of accuracy, latency, and unintended touch, whilst uncovering the importance of friction, aesthetics, and stroke beautification to users. The observed participant behaviour and recommended tangible goals should enhance the development and evaluation of future systems.
Today is a big day in the world of Michelle because I have lots of news to share! In addition to the CHI 2014 publication on the High Performance Stylus System, I am happy to report that I also have a follow-up paper that will be presented a Graphics Interface 2014 in Montreal entitled, “How Low Should We Go? Understanding the Perception of Latency While Inking”! (Yaaah again for no cell phone roaming fees to attend the conference!) As the paper is forthcoming, I can’t release all of the details but I can share the abstract and a short video that we shot. Once the full paper is available, I will provide a link to it.
Recent advances in hardware have enabled researchers to study the perception of latency. Thus far, latency research has utilized simple touch and stylus-based tasks that do not represent inking activities found in the real world. In this work, we report on two studies that utilized writing and sketching tasks to understand the limits of human perception. Our studies revealed that latency perception while inking is worse (~50 milliseconds) than perception while performing non-inking tasks reported previously (~2-7 milliseconds). We also determined that latency perception is not based on the distance from the stylus’ nib to the ink, but rather on the presence of a visual referent such as the hand or stylus. The prior and current work has informed the Latency Perception Model, a framework upon which latency knowledge and the underlying mechanisms of perception can be understood and further explored.
Although every accepted paper is cause for celebration, I am especially happy that this paper was accepted because the proposed Latency Perception Model is a nice summary of all the latency work that has been done by myself and others thus far. Here is the YouTube video summarizing our work: