Defining ubiquitous computing vs. augmented reality

(and vs. All Other Such Paradigms)

What’s the difference between Ubiquitous Computing (“ubicomp”) and Augmented Reality (“AR”)? I hear this question often, and you could replace “augmented reality” in that question with any of the following buzzy paradigms for people-interacting-with-computers: Virtual Reality, Pervasive Computing, Mobile Computing, Wearable Computing, Multi-Device Interaction, Cloud Computing, Intelligent Systems, Ambient Intelligence, Context-Aware Computing, Adaptive Systems, Machine Perception, Social Computing, Smart Environments, Everyware, and so on.

The perils of definition

Is ubicomp a superset or subset of <buzzy paradigm>? A fair question, but I’ve hesitated to propose a formal definition because they’re:

  • Overly confining — I’ve heard people say “oh, but ubicomp doesn’t address x or y” …When it does.
  • Often misused — I’ve heard people call the use of a browser on a smart phone “an example of ubicomp” “–no, that would be “mobile computing” …But do we care??
  • Usually degrade into never-ending semantic or ontological debates — I’ve heard long discussions about how “ubiquitous” means literally “everywhere at once,” so ubicomp can only be equivalent to some kind of all encompassing artificial intelligence.  … Please. We’re not trying to write science fiction here, we’re trying to create systems that help people throughout their life.

For the most part, I don’t find formal definitions useful; you can call it whatever suits your fancy. All that matters is that I understand what you mean when you use a term and that you understand what I mean when I use it (whether we use that term in the exact same way or not is immaterial). So, here’s what my colleagues and I generally mean when we talk about ubicomp.

Ubiquitous Computing is…

The attributes of a definition that carry lasting meaning are not technological properties (performance, cost, size, distribution, latency), but the core capabilities that the paradigm enables for usage.

Ubiquitous is the property of being or seeming to be everywhere. Its synonyms: omni-present, pervasive, everywhere, universal.

Computing is the act of calculation or generation of an output based on input. It can be carried out by a person alone (“she is computing the result in her notebook”) or with the support of technology (“the teacher is computing their scores on the mainframe”). It’s also possible to think of computing as being carried out by technology alone (“the laptop is computing their scores”) but in fact those cases are directed by a human operator.  In all cases, “computing” involves a human (or some other autonomous intelligence).

Usefulness is actually a pretty important attribute of Ubiquitous Computing (or “ubicomp”). Just as the sound of the proverbial tree falling in the woods only matters when someone is there to hear it, the act of computing only matters when it is of use to someone. Usefulness differentiates ubicomp from terms like “artificial intelligence” or “ambient intelligence” or “smart environments” — where the intelligence or smartness could, theoretically, exist for its own sake, not necessarily for the usefulness of others or those in an environment.

  • Synonymous (practically) with ubicomp are “pervasive computing” and “Everyware”, though the terms didn’t come into use until later.
  • A common characteristic in ubiquitous computing systems is  “multi-device interaction”, but it is possible to create ubiquitous computing systems where the user is primarily interacting with one device (e.g., a smart phone, an electronic kiosk).
  • Not necessarily (but often), ubicomp can involve “mobile computing”. This term implies that either the person or the computation is capable of being in motion, but  it would not necessarily be the case that such mobility spans all places (certainly my 3G network doesn’t go everywhere I do). So mobile computing is not necessarily wholly ubiquitous, nor does ubicomp wholly include mobility as a ubicomp system might be stationary (e.g., a home entertainment system).

So what’s the difference between Augmented Reality and Ubiquitous Computing?

Getting back to the question, Augmented Reality (like “mobile computing” as described above) is neither a subset or superset of Ubiquitous Computing.  Augmented Reality (AR) is the presentation of electronic information along with a real-world object, projected physically or as seen through an electronic display. Ubiquitous Computing (ubicomp) is the seamless integration of information services as we accomplish goals throughout our work and personal lives.

BOTH have to do with the use of information services in conjunction with real-world objects.
BUT one is about perceiving “reality”, and the other about the usefulness of the “computing” to our goals.

The key point of overlap, and the source of confusion to some, is that both AR and Ubicomp utilize machine perception to detect the state of the real world. AR systems typically use cameras, GPS, and electronic compass to detect the location and orientation of physical objects relative to each other. A Ubicomp system may also employ those same sensors along with others such as switches, thermistors, microphones, chemical detectors, strain gauges, accelerometers, and more. Such sensing technologies enable machine perception that is approaching the fidelity of human perceptions — of temperature, sound, sight, smell and taste, proprioception, balance, and motion,  respectively.

Cutting to the chase,

  • AR depends on machine perception technologies to detect the identity and physical configuration of objects relative to each other. It aims to project information alongside a physical object.
  • Ubicomp does not necessarily require that the information be displayed alongside one’s perception of the real-world items. Ubicomp uses machine perception to incorporate inputs that are not necessarily explicitly entered by human operators — such as physical states of motion (running, walking, driving, or riding?), attentional demands of the situation (driving in traffic or sitting on a train?), other people’s attributes (roles, demographics, or psychographics), and more. It further encompasses electronic information about things outside of one’s physical environment, perhaps adapting the presentation based on the attentional (driving in heavy traffic) and physical (arms full) demands of the user.

Ubiquitous Computing, like sands through the hourglass

In essence, Ubicomp research focuses on the use of information services throughout our everyday lives, which might include an AR-style of interaction. In that sense, Ubicomp might seem to cover everything; but then the term “Ubiquitous Computing” would be no more meaningful than “Computing” in general.

For PARC, ubicomp is not a superset or subset of anything, but deals with what exists in the interstices of other computing paradigms and research areas. For me, this includes:

  • Device Network Interoperability, Implicit Interaction, Human Micro-Behavior Analysis, Contextual Behavior Modeling, and Activity Awareness;
  • A growing number of applications such as: Secure Data Exchange, Persuasive Systems, Context-Aware Recommendation Systems, Behavior Modeling, Remote Monitoring and Troubleshooting; and
  • Future advances that realize other capabilities not currently on the roadmaps of other paradigms such as: Responsive Media (similar to Human-Robot Interaction but without the anthropomorphic robot), Ubiquitous Digital Assistance (systems that make decisions modeled on your personal priorities and tradeoffs), Life Coaches (systems that monitor and advise you to help attain your personal goals), Hyper-Presence (the ultimate extension of digital presence we see of instant messaging and Social Computing), and of course all sorts of other things.

More about these some other time.

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