Paper: The “Seen but Unnoticed” Vocabulary of Natural Touch: Revolutionizing Direct Interaction with Our Devices and One Another

In this Vision (for the UIST 2021 Symposium on User Interface Software & Technology), I argue that “touch” input and interaction remains in its infancy when viewed in context of the seen but unnoticed vocabulary of natural human behaviors, activity, and environments that surround direct interaction with displays.

Unlike status-quo touch interaction — a shadowplay of fingers on a single screen — I argue that our perspective of direct interaction should encompass the full rich context of individual use (whether via touch, sensors, or in combination with other modalities), as well as collaborative activity where people are engaged in local (co-located), remote (tele-present), and hybrid work.

We can further view touch through the lens of the “Society of Devices,” where each person’s activities span many complementary, oft-distinct devices that offer the right task affordance (input modality, screen size, aspect ratio, or simply a distinct surface with dedicated purpose) at the right place and time.

While many hints of this vision already exist in the literature, I speculate that a comprehensive program of research to systematically inventory, sense, and design interactions around such human behaviors and activities—and that fully embrace touch as a multi-modal, multi-sensor, multi-user, and multi-device construct—could revolutionize both individual and collaborative interaction with technology.

---

For the remote presentation, instead of a normal academic talk, I recruited my friend and colleague Nicolai Marquardt to have a 15-minute conversation with me about the vision and some of its implications:

Watch the “Seen but Unnoticed” UIST 2021 Vision presentation video on YouTube

---

Several aspects of this vision paper relate to a larger Microsoft Research project known as SurfaceFleet that explores the distributed systems and user experience implications of a “Society of Devices” in the New Future of Work.

---

Ken Hinckley. The “Seen but Unnoticed” Vocabulary of Natural Touch: Revolutionizing Direct Interaction with Our Devices and One Another. UIST Vision presented at The 34th Annual ACM Symposium on User Interface Software and Technology (UIST ’21). Non-archival publication, 5 pages. Virtual Event, USA, Oct 10-14, 2021.
https://arxiv.org/abs/2310.03958

[PDF] [captioned presentation video – mp4]

Paper: SurfaceFleet: Exploring Distributed Interactions Unbounded from Device, Application, User, and Time

SurfaceFleet is a multi-year project at Microsoft Research contributing a system and toolkit that uses resilient and performant distributed programming techniques to explore cross-device user experiences.

With appropriate design, these technologies afford mobility of user activity unbounded by device, application, user, and time.

The vision of the project is to enable a future where an ecosystem of technologies seamlessly transition user activity from one place to another — whether that “place” takes the form of a literal location, a different device form-factor, the presence of a collaborator, or the availability of the information needed to complete a particular task.

The goal is a Society of Technologies that fosters meaningful relationships amongst the members of this society, rather than any particular device.

This engenders mobility of user activity in a way that takes advantage of recent advances in networking and storage, and that supports consumer trends of multiple device usage and distributed workflows—not the least of which is the massive global shift towards remote work (bridging multiple users, on multiple devices, across local and remote locations).

---

In this particular paper, published at UIST 2020, we explored the trend for knowledge work to increasingly span multiple computing surfaces.

Yet in status quo user experiences, content as well as tools, behaviors, and workflows are largely bound to the current device—running the current application, for the current user, and at the current moment in time.

This work is where we first introduce SurfaceFleet as a system and toolkit founded on resilient distributed programming techniques. We then leverage this toolkit to explore a range of cross-device interactions that are unbounded in these four dimensions of device, application, user, and time.

As a reference implementation, we describe an interface built using Surface Fleet that employs lightweight, semi-transparent UI elements known as Applets.

Applets appear always-on-top of the operating system, application windows, and (conceptually) above the device itself. But all connections and synchronized data are virtualized and made resilient through the cloud.

For example, a sharing Applet known as a Portfolio allows a user to drag and drop unbound Interaction Promises into a document. Such promises can then be fulfilled with content asynchronously, at a later time (or multiple times), from another device, and by the same or a different user.

This work leans heavily into present computing trends suggesting that cross-device and distributed systems will have major impact on HCI going forward:

With Moore’s Law at an end, yet networking and storage exhibiting exponential gains, the future appears to favor systems that emphasize seamless mobility of data, rather than using any particular CPU.

At the same time, the ubiquity of connected and inter-dependent devices, of many different form factors, hints at a Society of Technologies that establishes meaningful relationships amongst the members of this society.

This favors the mobility of user activity, rather than using any particular device, to achieve a future where HCI can meet full human potential.

Overall, SurfaceFleet advances this perspective through a concrete system implementation as well as our unifying conceptual contribution that frames mobility as transitions in place in terms of device, application, user, and time—and the resulting exploration of techniques that simultaneously bridge all four of these gaps.

Watch SurfaceFleet video on YouTube

---

Frederik Brudy*, David Ledo*, Michel Pahud, Nathalie Henry Riche, Christian Holz, Anand Waghmare, Hemant Surale, Marcus Peinado, Xiaokuan Zhang, Shannon Joyner, Badrish Chandramouli, Umar Farooq Minhas, Jonathan Goldstein, Bill Buxton, and Ken Hinckley. SurfaceFleet: Exploring Distributed Interactions Unbounded from Device, Application, User, and Time.  In Proceedings of the 33rd Annual ACM Symposium on User Interface Software and Technology (UIST ’20). ACM, New York, NY, USA. Virtual Event, USA, October 20-23, 2020, pp. 7-21. https://doi.org/10.1145/3379337.3415874
* The first two authors contributed equally to this work.

[PDF] [30-second preview – mp4] [Full video – mp4] [Supplemental video “How to” – mp4 | Supplemental video on YouTube].

[Frederik Brudy and David Ledo’s SurfaceFleet virtual talk from UIST 2020 on YouTube]

Paper: The uncanny valley of haptics

This work explores a rather intriguing sensory illusion that can extend the sense of touch beyond the confines of your own body.

For a highly accessible discussion, please see the Scientific American Observations write-up of our work (“If (Virtual) Reality Feels Almost Right, It’s Exactly Wrong“).

And for a proper scientific write-up and analysis, see our Science Robotics cover article, The uncanny valley of haptics. Note the main article is short (per the format favored by Science) but the supplementary materials go into considerable depth. The full data, materials, and Azure notebook for the analysis are available as well.

nature materials also featured this work (“Zombie Materials“) but alas their article is paywalled.

---

Christopher C. Berger, Mar Gonzalez-Franco, Eyal Ofek and Ken Hinckley, The uncanny valley of haptics. Science Robotics, 2018. 3(17).
https://doi.org/10.1126/scirobotics.aar7010

[PDF] [Video on YouTube]

Paper: WritLarge: Ink Unleashed by Unified Scope, Action, & Zoom

Electronic whiteboards remain surprisingly difficult to use in the context of creativity support and design.

A key problem is that once a designer places strokes and reference images on a canvas, actually doing anything useful with key parts of that content involves numerous steps.

Hence, with digital ink, scope—that is, selection of content—is a central concern, yet current approaches often require encircling ink with a lengthy lasso, if not switching modes via round-trips to the far-off edges of the display.

Only then can the user take action, such as to copy, refine, or re-interpret their informal work-in-progress.

Such is the stilted nature of selection and action in the digital world.

But it need not be so.

By contrast, consider an everyday manual task such as sandpapering a piece of woodwork to hew off its rough edges. Here, we use our hands to grasp and bring to the fore—that is, select—the portion of the work-object—the wood—that we want to refine.

And because we are working with a tool—the sandpaper—the hand employed for this ‘selection’ sub-task is typically the non-preferred one, which skillfully manipulates the frame-of-reference for the subsequent ‘action’ of sanding, a complementary sub-task articulated by the preferred hand.

Therefore, in contrast to the disjoint subtasks foisted on us by most interactions with computers, the above example shows how complementary manual activities lend a sense of flow that “chunks” selection and action into a continuous selection-action phrase. By manipulating the workspace, the off-hand shifts the context of the actions to be applied, while the preferred hand brings different tools to bear—such as sandpaper, file, or chisel—as necessary.

The main goal of the WritLarge project, then, is to demonstrate similar continuity of action for electronic whiteboards. This motivated free-flowing, close-at-hand techniques to afford unification of selection and action via bimanual pen+touch interaction.

Accordingly, we designed WritLarge so that user can simply gesture as follows:

With the thumb and forefinger of the non-preferred hand, just frame a portion of the canvas.

And, unlike many other approaches to “handwriting recognition,” this approach to selecting key portions of an electronic whiteboard leaves the user in complete control of what gets recognized—as well as when recognition occurs—so as not to break the flow of creative work.

Indeed, building on this foundation, we designed ways to shift between flexible representations of freeform content by simply moving the pen along semantic, structural, and temporal axes of movement.

See our demo reel below for some jaw-dropping demonstrations of the possibilities for digital ink opened up by this approach.

Watch WritLarge: Ink Unleashed by Unified Scope, Action, and Zoom video on YouTube

---

Haijun Xia, Ken Hinckley, Michel Pahud, Xioa Tu, and Bill Buxton. 2017. WritLarge: Ink Unleashed by Unified Scope, Action, and Zoom. In Proceedings of the 2017 CHI Conference on Human Factors in Computing Systems (CHI’17). ACM, New York, NY, USA, pp. 3227-3240. Denver, Colorado, United States, May 6-11, 2017. Honorable Mention Award (top 5% of papers).
https://doi.org/10.1145/3025453.3025664

[PDF] [30 second preview – mp4 | YouTube] [Full video – mp4]

Paper: Thumb + Pen Interaction on Tablets

Modern tablets support simultaneous pen and touch input, but it remains unclear how to best leverage this capability for bimanual input when the nonpreferred hand holds the tablet.

We explore Thumb + Pen interactions that support simultaneous pen and touch interaction, with both hands, in such situations. Our approach engages the thumb of the device-holding hand, such that the thumb interacts with the touch screen in an indirect manner, thereby complementing the direct input provided by the preferred hand.

For instance, the thumb can determine how pen actions (articulated with the opposite hand) are interpreted.

Alternatively, the pen can point at an object, while the thumb manipulates one or more of its parameters through indirect touch.

Our techniques integrate concepts in a novel way that derive from radial menus (also known as marking menus) and spring-loaded modes maintained by muscular tension — as well as indirect input, and in ways that leverage multi-touch conventions.

Our overall approach takes the form of a set of probes, each representing a meaningfully distinct class of application. They serve as an initial exploration of the design space at a level which will help determine the feasibility of supporting bimanual interaction in such contexts, and the viability of the Thumb + Pen techniques in so doing.

Watch Thumb + Pen Interaction on Tablets video on YouTube

---

Ken Pfeuffer, Ken Hinckley, Michel Pahud, and Bill Buxton. 2017. Thumb + Pen Interaction on Tablets. In Proceedings of the 2017 CHI Conference on Human Factors in Computing Systems (CHI’17). ACM, New York, NY, USA, pp. 3254-3266 . Denver, Colorado, United States, May 6-11, 2017.
https://doi.org/10.1145/3025453.3025567

[PDF] [30s preview – mp4 | YouTube] [Full video – mp4]

Paper: As We May Ink? Learning from Everyday Analog Pen Use to Improve Digital Ink Experiences

This work sheds light on gaps and discrepancies between the experiences afforded by analog pens and their digital counterparts.

Despite the long history (and recent renaissance) of digital pens, the literature still lacks a comprehensive survey of what types of marks people make and what motivates them to use ink—both analog and digital—in daily life.

To capture the diversity of inking behaviors and tease out the unique affordances of pen-and ink, we conducted a diary study with 26 participants from diverse backgrounds.

From analysis of 493 diary entries we identified 8 analog pen-and-ink activities, and 9 affordances of pens. We contextualized and contrasted these findings using a survey with 1,633 respondents and a follow-up diary study with 30 participants, observing digital pens.

Our analysis revealed many gaps and research opportunities based on pen affordances not yet fully explored in the literature.

---

Yann Riche, Nathalie Henry Rich, Ken Hinckley, Sarah Fuelling, Sarah Williams, and Sheri Panabaker. 2017. As We May Ink? Learning from Everyday Analog Pen Use to Improve Digital Ink Experiences. In Proceedings of the 2017 CHI Conference on Human Factors in Computing Systems (CHI’17). ACM, New York, NY, USA, pp. 3241-3253. Denver, Colorado, United States, May 6-11, 2017.
https://doi.org/10.1145/3025453.3025716

[PDF] [CHI 2017 Talk Slides (PowerPoint)]

Scientific American Observations: If (Virtual) Reality Feels Almost Right, It’s Exactly Wrong

Scientific American Observations
If (Virtual) Reality Feels Almost Right, It’s Exactly Wrong: How adding touch to VR can lead to an “uncanny valley” of sensations—and what we can do about it.
Mar Gonzalez-Franco, Christopher C Berger, and Ken Hinckley. April 19, 2018.

A general-interest overview of the fascinating sensory illusions revealed by our Science Robotics paper The uncanny valley of haptics.

Paper: Wearables as Context for Guiard-abiding Bimanual Touch

This particular paper has a rather academic-sounding title, but at its heart it makes a very simple and interesting observation regarding touch that any user of touch-screen technology can perhaps appreciate.

The irony is this: when interaction designers talk about “natural” interaction, they often have touch input in mind. And so people tend to take that for granted. What could be simpler than placing a finger — or with the modern miracle of multi-touch, multiple fingers — on a display?

And indeed, an entire industry of devices and form-factors — everything from phones, tablets, drafting-tables, all the way up to large wall displays — has arisen from this assumption.

Yet, if we unpack “touch” as it’s currently realized on most touchscreens, we can see that it remains very much a poor man’s version of natural human touch.

For example, on a large electronic-whiteboard such as the 84″ Surface Hub, multiple people can work upon the display at the same time. And it feels natural to employ both hands — as one often does in a wide assortment of everyday manual activities, such as indicating a point on a whiteboard with your off-hand as you emphasize the same point with the marker (or electronic pen).

Yet much of this richness — obvious to anyone observing a colleague at a whiteboard — represents context that is completely lost with “touch” as manifest in the vast majority of existing touch-screen devices.

For example:

• Who is touching the display?
• Are they touching the display with one hand, or two?
• And if two hands, which of the multiple touch-events generated come from the right hand, and which come from the left?

Well, when dealing with input to computers, the all-too-common answer from the interaction designer is a shrug, a mumbled “who the heck knows,” and a litany of assumptions built into the user interface to try and paper over the resulting ambiguities, especially when the two factors (which user, and which hand) compound one another.

The result is that such issues tend to get swept under the rug, and hardly anybody ever mentions them.

But the first step towards a solution is recognizing that we have a problem.

This paper explores the implications of one particular solution that we have prototyped, namely leveraging wearable devices on the user’s body as sensors that can augment the richness of touch events.

A fitness band worn on the non-preferred hand, for example, can sense the impulse resulting from making finger-contact with a display through its embedded motion sensors (accelerometers and gyros). If the fitness band and the display exchange information and id’s, the touch-event generated can then be associated with the left hand of a particular user. The inputs of multiple users instrumented in this manner can then be separated from one another, as well, and used as a lightweight form of authentication.

That then explains the “wearable” part of “Wearables as Context for Guiard-abiding Bimanual Touch,” the title of my most recent paper, but what the heck does “Guiard-abiding” mean?

Well, this is a reference to classic work by a research colleague, Yves Guiard, who is famous for a 1987 paper in which he made a number of key observations regarding how people use their hands — both of them — in everyday manual tasks.

Particularly, in a skilled manipulative task such as writing on a piece of paper, Yves pointed out (assuming a right-handed individual) three general principles:

• Left hand precedence: The action of the left hand precedes the action of the right; the non-preferred hand first positions and orients the piece of paper, and only then does the pen (held in the preferred hand, of course) begin to write.
• Differentiation in scale: The action of the left hand tends to occur at a larger temporal and spatial scale of motion; the positioning (and re-positioning) of the paper tends to be infrequent and relatively coarse compared to the high-frequency, precise motions of the pen in the preferred hand.
• Right-to-Left Spatial Reference: The left hand sets a frame of reference for the action of the right; the left hand defines the position and orientation of the work-space into which the preferred hand inserts its contributions, in this example via the manipulation of a hand-held implement — the pen.

Well, as it turns out these three principles are very deep and general, and they can yield great insight into how to design interactions that fully take advantage of people’s everyday skills for two-handed (“bimanual”) manipulation — another aspect of “touch” that interaction designers have yet to fully leverage for natural interaction with computers.

This paper is a long way from a complete solution to the paucity of modern touch-screens but hopefully by pointing out the problem and illustrating some consequences of augmenting touch with additional context (whether provided through wearables or other means), this work can lead to more truly “natural” touch interaction — allowing for simultaneous interaction by multiple users, both of whom can make full and complementary use of their hard-won manual skill with both hands — in the near future.

---

Andrew M. Webb, Michel Pahud, Ken Hinckley, and Bill Buxton. 2016. Wearables as Context for Guiard-abiding Bimanual Touch. In Proceedings of the 29th Annual ACM Symposium on User Interface Software and Technology (UIST ’16). ACM, New York, NY, USA, 287-300. Tokyo, Japan, Oct. 16-19, 2016. https://doi.org/10.1145/2984511.2984564
[PDF] [Talk slides PDF] [30 second preview on YouTube] [Full video – MP4]

Book Chapter: Inking Outside the Box — How Context Sensing Affords More Natural Pen (and Touch) Computing

“Pen” and “Touch” are terms that tend to be taken for granted these days in the context of interaction with mobiles, tablets, and electronic-whiteboards alike.

Yet, as I have discussed in many articles here, even in the simplest combination of these modalities — that of “Pen + Touch” — new opportunities for interaction design abound.

And from this perspective we can go much further still.

Take “touch,” for example.

What does this term really mean in the context of input to computers?

Is it just when the user intentionally moves a finger into contact with the screen?

What if the palm accidentally brushes the display instead — is that still “touch?”

Or how about the off-hand, which plays a critical but oft-unnoticed role in gripping and skillfully orienting the device for the action of the preferred hand? Isn’t that an important part of “touch” as well?

Well, there’s good reason to argue that from the human perspective, these are all “touch,” even though most existing devices only generate a touch-event at the moment when a finger comes into contact with the screen.

Clearly, this is a very limited view, and clearly with greater insight of the context surrounding a particular touch (or pen, or pen + touch) event, we could enhance the naturalness of working with computers considerably.

This chapter, then, works through a series of examples and perspectives which demonstrate how much richness there is in such a re-conception of direct interaction with computers, and thereby suggests some directions for future innovations and richer, far more expressive interactions.

---

Hinckley, Ken, and Buxton, Bill. Inking Outside the Box: How Context Sensing Affords More Natural Pen (and Touch) Computing. Appears as Chapter 3 in Revolutionizing Education with Digital Ink: The Impact of Pen and Touch Technology on Education (Human-Computer Interaction Series), First Edition (2016). Ed. by Tracy Hammond, Stephanie Valentine, & Aaron Adler. Published by Springer, Cham. June 13, 2016. https://doi.org/10.1007/978-3-319-31193-7_3

[PDF – Author’s draft]

P.S.: I’ve linked to the draft of the chapter that I submitted to the publisher, rather than the final version, as the published copy-edit muddied the writing by a gross misapplication of the Chicago Manual of Style, and in so doing introduced many semantic errors as well. Despite my best efforts I was not able to convince the publisher to fully reverse these undesired and unfortunate “improvements.” As such, my draft may contain some typographical errors or other minor discrepancies from the published version, but it is the authoritative version as far as I am concerned.

Paper: Pre-Touch Sensing for Mobile Interaction

I have to admit it: I feel as if I’m looking at the sunrise of what may be a whole new way of interacting with mobile devices.

When I think about it, the possibilities bathe my eyes in a golden glow, and the warmth drums against my skin.

And in particular, my latest research peers out across this vivid horizon, to where I see touch — and mobile interaction with touchscreens in particular — evolving in the near future.

As a seasoned researcher, my job (which in reality is some strange admixture of interaction design, innovator, and futurist) is not necessarily to predict the future, but rather to invent it via extrapolation from a sort of visionary present which occupies my waking dreams.

I see things not as they are, but as they could be, through the lens afforded by a (usually optimistic) extrapolation from extant technologies, or those I know are likely to soon become more widely available.

With regards to interaction with touchscreens in particular, it has been clear to me for some time that the ability to sense the fingers as they approach the device — well before contact with the screen itself — is destined to become commonplace on commodity devices.

This is interesting for a number of reasons.

And no, the ability to do goofy gestures above the screen, waving at it frantically (as if it were a fancy-pants towel dispenser in a public restroom) in some dim hope of receiving an affirmative response, is not one of them.

In terms of human capabilities, one obviously cannot touch the screen of a mobile device without approaching it first.

But what often goes unrecognized is that one also must hold the device, typically in the non-preferred hand, as a precursor to touch. Hence, how you hold the device — the pattern of your grip and which hand you hold it in — are additional details of context that are more-or-less wholly ignored by current mobile devices.

So in this new work, my colleagues and I collectively refer to these two precursors of touch — approach and the need to grip the device — as pre-touch.

And it is my staunch belief that the ability to sense such pre-touch information could radically transform the mobile ‘touch’ interfaces that we all have come to take for granted.

You can get a sense of these possibilities, all implemented on a fully functional mobile phone with pre-touch sensing capability, in our demo reel below:

The project received a lot of attention, and coverage from many of the major tech blogs and other media outlets, for example:

• The Verge (“Microsoft’s hover gestures for Windows phones are magnificent”)
• SlashGear (“Smartphones next big thing: ‘Pre-Touch’”)
• Business Insider (“Apple should definitely copy Microsoft’s incredible finger-sensing smartphone technology”)
• And Fast Company Design (and again in “8 Incredible Prototypes That Show The Future Of Human-Computer Interaction.”) (paywalled)

But I rather liked the take that Silicon Angle offered, which took my concluding statement from the video above:

Taken as a whole, our exploration of pre-touch hints that the evolution of mobile touch may still be in its infancy – with many possibilities, unbounded by the flatland of the touchscreen, yet to explore.

 And then responded as follows:

This is the moon-landing-esque conclusion Microsoft comes to after demonstrating its rather cool pre-touch mobile technology, i.e., a mobile phone that senses what your fingers are about to do.

While this evolution of touch has been coming in the research literature for at least a decade now, what exactly to do with above- and around-screen sensing (especially in a mobile setting) has been far from obvious. And that’s where I think our work on pre-touch sensing techniques for mobile interaction distinguishes itself, and in so doing identifies some very interesting use cases that have never been realized before.

The very best of these new techniques possess a quality that I love, namely that they have a certain surprising obviousness to them:

The techniques seem obvious — but only in retrospect.

And only after you’ve been surprised by the new idea or insight that lurks behind them.

If such an effort is indeed the first hint of a moonshot for touch, well, that’s a legacy for this project that I can live with.

---

UPDATE: The talk I gave at the CHI 2016 conference on this project is now available. Have a gander if you are so inclined.

---

Ken Hinckley, Seongkook Heo, Michel Pahud, Christian Holz, Hrvoje Benko, Abigail Sellen, Richard Banks, Kenton O’Hara, Gavin Smyth, William Buxton. 2016. Pre-Touch Sensing for Mobile Interaction. In Proceedings of the 2016 CHI Conference on Human Factors in Computing Systems (CHI ’16). ACM, New York, NY, USA, p. 2869-2881. San Jose, CA, May 7-12, 2016. http://dx.doi.org/10.1145/2858036.2858095

[PDF] [Talk slides PPTX] [video – MP4] [30 second preview – MP4] [Watch on YouTube]

Watch Pre-Touch Sensing for Mobile Interaction video on YouTube