INSTITUTIONEN FÖR SYSTEMTEKNIK LULEÅ TEKNISKA UNIVERSITET Alternative Interfaces SMD157 Human-Computer Interaction Fall 2002 Nov-27-03 SMD157, Alternate Interfaces 1 L Overview Limitation of the Mac interface The anti-mac interface Challenges of the anti-mac interface Multi-modal, augmented reality and virtual reality Nov-27-03 SMD157, Alternate Interfaces 2 L INSTITUTIONEN FÖR SYSTEMTEKNIK LULEÅ TEKNISKA UNIVERSITET Limitations of the Mac Interface Nov-27-03 SMD157, Alternate Interfaces 3 L 1
The WIMP Interface Windows Icons Menus Pointers Nov-27-03 SMD157, Alternate Interfaces 4 L Historical Background The original Mac was for people without previous computer experience Targeted towards office applications Limited computational power and memory (128 KB) Small black and white display (512 x 384) Originally a stand-alone machine Nov-27-03 SMD157, Alternate Interfaces 5 L Fundamental Principles of the Mac Metaphors Direct manipulation See and point Consistency What You See Is What You Get User control and stability Feedback and dialog Forgiveness Aesthetic integrity Modeless Nov-27-03 SMD157, Alternate Interfaces 6 L 2
Metaphors for the Interface Problems: - limits what is possible - locks design - cause misunderstandings Examples of Problem Metaphors - Steering a tractor + pulling reins (loosen - forward, pull - back and stop) - The book metaphor is outdated + Video games and TV (channel flipping) is more common - Computer interfaces are used in traditional media + Menus in news programs Nov-27-03 SMD157, Alternate Interfaces 7 L Direct Manipulation Engages the user at the lowest level of operation Many steps required Repetitive action often needed Problems with abstractions Imprecise (language and formulas can be more exact) Nov-27-03 SMD157, Alternate Interfaces 8 L See and Point Not as expressive as language Pointing is a primitive form of communication Interaction is stateless (no history) Nov-27-03 SMD157, Alternate Interfaces 9 L 3
Consistency Life is inconsistent People are inconsistent Things do not look the same Forcing consistency can cause conflicts Nov-27-03 SMD157, Alternate Interfaces 10 L WYSIWYG But, it often means What You See Is All There Is Problems: - Limits manipulation to the surface aspect of the representation - Only one visualization of many possible ones (the printed one) - No access to the underlying structure - Not possible to manipulate structure with a program For example, documents have rich underlying structure Nov-27-03 SMD157, Alternate Interfaces 11 L User Control and Stability We do not want to be in control all the time - Flying an airplane, toasting bread, TV shows Control requires mental energy Networked environments means that other users are present - The phone rings, mail, push technologies Agents become more commonplace - answering machine Things change because the world changes - the web Nov-27-03 SMD157, Alternate Interfaces 12 L 4
Forgiveness Actions reversible and user warned about irreversible data loss But, this can be annoying Example, copying to a full diskette in a trash can metaphor system - Two actions required, deleting and emptying the trash - Problem, statelessness Nov-27-03 SMD157, Alternate Interfaces 13 L Aesthetic Integrity Simple, clean, consistent interface Outgrowth of limited expressiveness Also, limits expressiveness - Easy to understand limits what can be presented Nov-27-03 SMD157, Alternate Interfaces 14 L Modeless In reality, interfaces aren t People need to concentrate and modes help focus user action Mode visibility is what is important Nov-27-03 SMD157, Alternate Interfaces 15 L 5
INSTITUTIONEN FÖR SYSTEMTEKNIK LULEÅ TEKNISKA UNIVERSITET The Anti-Mac Interface Nov-27-03 SMD157, Alternate Interfaces 16 L Anti-Mac Interfaces Try to overcome the limits of the Mac-like interface Language is central Rich internal representation of objects Expressive interfaces Expert users Shared control Nov-27-03 SMD157, Alternate Interfaces 17 L Language Current interfaces are equivalent to Point and Grunt One cannot operate on sets of things or classes without language Language provides - Abstractions, - State, - History, - User programming Not full natural language, but adventure-game level Nov-27-03 SMD157, Alternate Interfaces 18 L 6
Language System contains - Dictionary (spelling correction) - Thesaurus (synonym recognition) - Displays of what is possible - User model Negotiates with the user to refine the query Nov-27-03 SMD157, Alternate Interfaces 19 L Internal Representation of Objects, More Expressive Interfaces More underlying structure is available to the user Differences will be expressed in the interface - Continues the trend of different icons for different document types - Beyond the open program Large more capable displays Nov-27-03 SMD157, Alternate Interfaces 20 L Experts Users, Shared Control Users will be familiar with computers - Less need to trade off in favor of ease of learning - Users will be more skilled in computer use More routine task will be delegated to agents Users will cooperate to perform tasks Nov-27-03 SMD157, Alternate Interfaces 21 L 7
The Mac versus the Anti-Mac The Mac - Metaphors - Direct manipulation - See and point - Consistency - WYSIWYG - User Control - Feedback and dialog - Forgiveness - Aesthetic integrity - Modeless The Anti-Mac - Reality - Delegation - Describe and command - Diversity - Represent meaning - Shared control - System handles details - Model user actions - Graphic variety - Richer cues Nov-27-03 SMD157, Alternate Interfaces 22 L INSTITUTIONEN FÖR SYSTEMTEKNIK LULEÅ TEKNISKA UNIVERSITET Challenges of the Anti-Mac Interface The Anti- Anti-Mac Interface Nov-27-03 SMD157, Alternate Interfaces 23 L Metaphors versus Reality What level of reality is needed? - Knowledge of disk organization isn t needed. Why won t better metaphor s work? - The trash as access to a structure of deleted files - A link to a directory is a directory, not a special file The right representation at the right level is usually an abstraction, i.e., a metaphor Nov-27-03 SMD157, Alternate Interfaces 24 L 8
Diversity, Graphic Variety, and Richer Cues Users must discriminate - Human perception is limited - Even more so under + High cognitive load + Stress Design of communicative visual languages is poorly understood Nov-27-03 SMD157, Alternate Interfaces 25 L Delegation Plus Describe & Command Requires - Trustworthy subordinate systems - Clear specification of intent - Verification of correctness End-user programming is problematic - Conditional expression difficult, but required for rules - Abstract parameters difficult, but required as size grows - Debugging difficult, but required for trustworthiness Deterministic results paramount Nov-27-03 SMD157, Alternate Interfaces 26 L Shared Control and the System Handles the Details Who checks the system? What explanations of history are available? Do users really want non-deterministic systems? - If the user can t construct a mental model, it s nondeterministic - Users can t construct models of complex systems What is the potential for abuse? Nov-27-03 SMD157, Alternate Interfaces 27 L 9
Modeling User Actions User models are complex Current systems are limited - Limited domains of application (e.g., music recommendation) - Do not cope well with dynamics - Little better than mean response Nov-27-03 SMD157, Alternate Interfaces 28 L Summary Current interfaces are limiting Some users will: - Have the training necessary to operate - Want more flexibility - Be comfortable with asynchronous action A more reasonable near term answer is: - A bigger display with more diverse graphics - Access to system objects via a scripting language - Limited capability filters Nov-27-03 SMD157, Alternate Interfaces 29 L INSTITUTIONEN FÖR SYSTEMTEKNIK LULEÅ TEKNISKA UNIVERSITET Multimodal, Augmented Reality and Virtual Reality Nov-27-03 SMD157, Alternate Interfaces 30 L 10
Multimodal Using more than one input channel simultaneously - E.g., speech and pointing. It is closer to the way people communicate. It is difficult to do. - Different modes have different command orders + Put that there (voice/gesture) versus + That there put (direct manipulation) - Current operating systems do not consider time. - Interpreting gestures and speech is error prone Nov-27-03 SMD157, Alternate Interfaces 31 L The Efficiency of Multimodal Interaction for a Map-Based Task Video CHI 2000 Nov-27-03 SMD157, Alternate Interfaces 32 L Total Immersion Systems Pros: - Can provide a very realistic simulation. - Can provide an environment which is impossible to build physically. Cons: - Current technology is uncomfortable or user- dependent. - Tracking delays can destroy the illusion. - Fatigue effects are unknown. (Think about repetitive stress injuries in VR.) - Most display resolutions are too low. Nov-27-03 SMD157, Alternate Interfaces 33 L 11
The Well Dressed VRist? Nov-27-03 SMD157, Alternate Interfaces 34 L Interfaces Using Physical Devices in Total Immersion Systems Video CHI 99 Nov-27-03 SMD157, Alternate Interfaces 35 L Augmented Reality Systems Pros: - Less technologically demanding than total immersion. - Does not preclude the normal work environment. Cons: - Current technology is still uncomfortable or user- dependent. - Tracking delays are still a problem. - Background can interfere with augmented reality images. Nov-27-03 SMD157, Alternate Interfaces 36 L 12
Navigation Methods for an Augmented Reality System Video CHI 2000 Nov-27-03 SMD157, Alternate Interfaces 37 L Palmtop Display for Remote Control, Haptic Feedback Video CHI 96 Nov-27-03 SMD157, Alternate Interfaces 38 L Questions? Nov-27-03 SMD157, Alternate Interfaces 39 L 13