jon@kitty.austin.ibm.com (Werner) (06/13/91)
Are there any papers written dealing with the use of touchscreens as an alternate input device in environments which don not have enough desk space for a keyboard or a mouse? -- ______________________________________________________________________________ jon@innerdoor.austin.ibm.com * Insert Standard Disclaimer here * IBM Advanced Workstations Division Austin, Texas USA 512-823-5156
jones@pyrite.cs.uiowa.edu (Douglas W. Jones,201H MLH,3193350740,3193382879) (06/13/91)
From article <8435@awdprime.UUCP>, by jon@kitty.austin.ibm.com (Werner): > Are there any papers written dealing with the use of touchscreens as an > alternate input device in environments which don not have enough desk > space for a keyboard or a mouse? I don't know of any papers, but as a long-term touch-panel user, I much prefer mice, trackballs, or knobs on my keyboard. I used the U of Illinois Plato touch panels between 1973 and 1980, and the big problems are: 1) You have to lift your hand up from the keyboard, perhaps a foot, to touch the screen. This slows you down compared to horizontal moves to a mouse. 2) No matter how good the anti-reflection coating on your screen is, fingerprints tend to defeat it. If you've got a touch panel, you'll need to wash it almost daily to keep the glare down. 3) If you have touch-intensive software, where you spend long periods holding your hand up to the screen poking here and there, your arm gets tired. I remember after some sessions debugging a particular touch-intensive piece of computer aided instructional material, my arm began to ache quite intensely. I've never experienced that kind of reaction to "desktop pointers" like mice. 4) Touch panels aren't particularly accurate. Even if you use a modern thin-film touch panel, there is a real problem with paralax. The front of a CRT display is quite thick, and the push button size we typically use with mice is small enough that it can be very hard to find the right spot on the screen to touch to get a particular button and not its surrounding area. The Iowa City Public Library on-line card catalog has been touch screen based for a few years now, and I've had numerous paralax problems with it, even thoug it has nice big on-screen push buttons. Doug Jones jones@cs.uiowa.edu it's
laforce@krypton.arc.nasa.gov (Soren LaForce) (06/13/91)
In article <8435@awdprime.UUCP>, jon@kitty.austin.ibm.com (Werner) writes... >Are there any papers written dealing with the use of touchscreens as an >alternate input device in environments which don not have enough desk >space for a keyboard or a mouse? >-- I don't know of any papers. There is an army/nasa project at ames research (Mountain View, ca) called CSRFD (Crew Station Research and Dev. Facility) that uses touch screens in a "glass cockpit" helicoptor simulator. You may be able to get some info from them. My experience with CSRDF was not too impressive. The "buttons" were fairly large, about 1"x1.25" (this was a few years ago so the details are a bit fuzzy...). The problem I had was getting the touch screen to respond. I don't think it was paralax, in any event, given the "buttton" size it SHOULDN'T have been paralax. I was told that the "button" location was set in software, and could be changed for different configurations. Perhaps the "buttons" were not configured correctly. It is also possible that the contacts in the screen were not performing well. I was not involved with the project and don't know enough to form a really solid opinion. On the other hand, it would be very dificult for someone to sell me a touch screen device. Non-technical complaints were: had to remove hands from controls to operate, could hit wrong button too easily, had to take attention away from the out the window display to select, etc. Some of the problems would not apply to a computer terminal, i.e. the touch screen is not in conflict with the out the window display (remember, I saw this stuff in a helicoptor simulator). Some problems would carry over, hands moving from controls/keyboard to screen. Did anyone else notice that when Mac users get proficent, they stop using the mouse/trackball and use the KEYBOARD! I think there is a message here... --Soren laforce@krypton.arc.nasa.gov
sears@tove.cs.umd.edu (Andrew Sears) (06/13/91)
In article <6460@ns-mx.uiowa.edu> jones@pyrite.cs.uiowa.edu (Douglas W. Jones,201H MLH,3193350740,3193382879) writes: >From article <8435@awdprime.UUCP>, by jon@kitty.austin.ibm.com (Werner): > >> Are there any papers written dealing with the use of touchscreens as an >> alternate input device in environments which don not have enough desk >> space for a keyboard or a mouse? > >I don't know of any papers, but as a long-term touch-panel user, I much >prefer mice, trackballs, or knobs on my keyboard. > >I used the U of Illinois Plato touch panels between 1973 and 1980, and There is a growing number of articles published on touchscreens, many of which have been written by members of the lab I work in, HCIL at the University of Maryland. First, I'd like to point out that touchscreens have improved dramatically in recent years. In addition, many of the problems that you mention have been investigated. >the big problems are: > > 1) You have to lift your hand up from the keyboard, perhaps a foot, > to touch the screen. This slows you down compared to horizontal > moves to a mouse. This is not necessarily true. There have been some studies that compared the touchscreen and mouse for tasks that involve typing. Typically, the touchscreen proves faster than the mouse. This is believed to be due to the fact that the user does not have to divert their attention from the screen to find the mouse. > > 2) No matter how good the anti-reflection coating on your screen is, > fingerprints tend to defeat it. If you've got a touch panel, you'll > need to wash it almost daily to keep the glare down. Glare can be a problem with touchscreens. However, touchscreen manufacturers are always decreasing glare. This combined with careful lighting can dramatically reduce this problem. The touchscreens in our lab tend to need very infrequent cleaning. Actually, the thin film of oil from your finger tends to prevent dust from accumulating. > > 3) If you have touch-intensive software, where you spend long periods > holding your hand up to the screen poking here and there, your arm > gets tired. I remember after some sessions debugging a particular > touch-intensive piece of computer aided instructional material, my > arm began to ache quite intensely. I've never experienced that kind > of reaction to "desktop pointers" like mice. This has always been a common complaint. However, simply changing the angle the monitor is mounted at can dramatically reduce this problem. We have conducted a study comparing several alternatives, 30, 45, and 75 degrees from horizontal. The 75 degree angle (near normal monitor position) was a clear looser. Additional studies by researchers in Sweden appear to support our results that indicate placement at approximately 30 degrees from horizontal is more comfortable and preferred. An article in the Journal of the American Optometric Association also suggests that lower screen placements will reduce eye strain. > > 4) Touch panels aren't particularly accurate. Even if you use a modern > thin-film touch panel, there is a real problem with paralax. The > front of a CRT display is quite thick, and the push button size we > typically use with mice is small enough that it can be very hard to > find the right spot on the screen to touch to get a particular > button and not its surrounding area. The Iowa City Public Library > on-line card catalog has been touch screen based for a few years > now, and I've had numerous paralax problems with it, even thoug it > has nice big on-screen push buttons. Touchscreens can be very accurate if used correctly. New touchscreen technologies offer resolusion of over 1000x1000 on an IBM PC screen. If appropriate feedback is provided and the correct selection strategy used, users with moderate experience can select even a single pixel from a 13 inch EGA monitor (under 1mm square). Studies have shown that novice users can select targets as small as 2mm per side as fast as they can with a mouse without any loss of accuracy. > > Doug Jones > jones@cs.uiowa.edu Well, this is long enough already. If anyone is interested in references for what I've stated here, or just additional references on touchscreen research (my own or others) please feel free to send me email (sears@cs.umd.edu). I will be more than happy to aim you at some of the more recent literature on touchscreens. Andrew Sears ----------------------------------------------------------------------------- Andrew Sears sears@CS.umd.edu Human-Computer Interaction Laboratory University of Maryland, College Park, MD 20742 (301) 405-2725
rsw@cs.brown.EDU (Bob Weiner) (06/14/91)
In article <6460@ns-mx.uiowa.edu> jones@pyrite.cs.uiowa.edu (Douglas W. Jones,201H MLH,3193350740,3193382879) writes: > From article <8435@awdprime.UUCP>, by jon@kitty.austin.ibm.com (Werner): > > I don't know of any papers, but as a long-term touch-panel user, I much > prefer mice, trackballs, or knobs on my keyboard. > > I used the U of Illinois Plato touch panels between 1973 and 1980, and > the big problems are: Mr. Jones painful experiences with touchscreens is a fine example of why a newsgroup like this exists. Often computer interface designers know little about ergonomics and usability and they put everything they know into their designs. Present a new technology and they try to make it fit with their old designs rather than contemplating the liberating aspects of the technology. Touchscreens hold much promise because of the greater level of direct manipulation they provide over indirect pointing devices. But interfaces need to be designed for direct versus indirect pointing. > > 1) You have to lift your hand up from the keyboard, perhaps a foot, > to touch the screen. This slows you down compared to horizontal > moves to a mouse. Mount the screen in a desk at a slight upward angle. You still have to move your hand but not as far and you don't have to raise your arm. A keyboard tray can be made to swing up and over or down and under out of the way for intensive touch screening. Some notebook computers will not have a keyboard but will rely solely on a touchscreen and pen input. > > 2) No matter how good the anti-reflection coating on your screen is, > fingerprints tend to defeat it. If you've got a touch panel, you'll > need to wash it almost daily to keep the glare down. Find a nicely balanced pen-like object with a blunt end and use it. No fingerprints. A number of touch screens do not actually require that their surface be touched but humans seem to love to jam their fingertips forward. My rule is that fingers should never touch a CRT, especially when indicating a point on a screen to a friend. Everyone should learn this. > > 3) If you have touch-intensive software, where you spend long periods > holding your hand up to the screen poking here and there, your arm > gets tired. I remember after some sessions debugging a particular > touch-intensive piece of computer aided instructional material, my > arm began to ache quite intensely. I've never experienced that kind > of reaction to "desktop pointers" like mice. > Carefully contoured desktops with wrist supports and the screen embedded in the desk can eliminate most of this fatigue. > 4) Touch panels aren't particularly accurate. Even if you use a modern > thin-film touch panel, there is a real problem with paralax. Shouldn't flat screens reduce this? > The > front of a CRT display is quite thick, and the push button size we > typically use with mice is small enough that it can be very hard to > find the right spot on the screen to touch to get a particular > button and not its surrounding area. Mice and touch screen interfaces should not work the same way, although they may have many similariities to maintain interface consistency. With different interfaces can come different actuator object sizes. -- Bob Weiner rsw@cs.brown.edu
acl3k@onyx.cs.Virginia.EDU (Allan Christian Long) (06/14/91)
One thing that hasn't been mentioned is that with a touchscreen, your hand obscures the screen when you use it. While this may not be a problem for some applications, for others it could be very inconvenient. Just my $0.02 worth. A. Chris Long, Jr. acl3k@virginia.edu
jon@kitty.austin.ibm.com (Werner) (06/14/91)
What are your thoughts on the z-axis surface acoustic wave touchscreen from Elographics. We have used the z value to define mouse clicks in the X Windows environment and it seems to work nicely. -- ______________________________________________________________________________ jon@innerdoor.austin.ibm.com * Insert Standard Disclaimer here * IBM Advanced Workstations Division Austin, Texas USA 512-823-5156
cdshaw@cs.UAlberta.CA (Chris Shaw) (06/14/91)
In article rsw@cs.brown.EDU (Bob Weiner) writes: >Mount the screen in a desk at a slight upward angle. This means that you need a low-profile screen. A deep CRT won't make it, because you can't sit at your desk with your legs stretched out. >Some notebook computers will not >have a keyboard but will rely solely on a touchscreen and pen input. Certainly this is self-consistent. But, my handwriting is hard to read, and after a mere year of using text editors to enter the text of papers, I gave up composing on paper entirely. I don't want to go back. I have also lost a significant amount of hand fitness, which makes picking up handwriting even more of a chore. >> 2) No matter how good the anti-reflection coating on your screen is, >> fingerprints tend to defeat it. If you've got a touch panel, you'll >> need to wash it almost daily to keep the glare down. > >Find a nicely balanced pen-like object with a blunt end and use it. Holding a pen while typing is difficult. If you have to pick up something, pick up a mouse! >A number of touch screens do not actually require that their surface be >touched but humans seem to love to jam their fingertips forward. This is because constrained selection is easier than unconstrained selection. Using a 3D technique to select a 2D object is silly. The tactile feedback is useful, also. >My rule is that fingers should never touch a CRT, especially when >indicating a point on a screen to a friend. Everyone should learn this. Well, yes and no. I think everyone should at least select with their fingernails (back of hand facing screen). >Carefully contoured desktops with wrist supports and the screen embedded >in the desk can eliminate most of this fatigue. That's an awful lot of expensive, non-portable furniture, given a traditional output device like a CRT. >Bob Weiner rsw@cs.brown.edu -- Chris Shaw University of Alberta cdshaw@cs.UAlberta.ca Now with new, minty Internet flavour! CatchPhrase: Bogus as HELL !
yee@osf.org (Michael K. Yee) (06/14/91)
In article <1991Jun13.235714.17297@cs.UAlberta.CA> cdshaw@cs.UAlberta.CA (Chris Shaw) writes: > >A number of touch screens do not actually require that their surface be > >touched but humans seem to love to jam their fingertips forward. > > This is because constrained selection is easier than unconstrained > selection. Using a 3D technique to select a 2D object is silly. > The tactile feedback is useful, also. Ahh, tactile feedback... This is my biggest complaint against touchscreens. There are no tactile feedback on any of the touchscreens I have seen. Even though a mouse is an indirect input device (i.e. moving the mouse moves the pointer on the screen), at least a mouse has REAL buttons. Touchscreens can ONLY provide visual and audio feedback. I think audio and visual feedback are great feedback mechanisms, but they are no replacement for the tactile feedback of a real button. =Mike -- == Michael K. Yee <yee@osf.org> -+- OSF/Motif Team == Open Software Foundation - 11 Cambridge Center - Cambridge, MA 02142 == "Live simply, so that others may simply live."
plaisant@witsend.cs.umd.edu (Catherine Plaisant-S) (06/14/91)
Since the touchscreen discussion is still going... Here is a list of
publications from the Human-Computer Interaction Laboratory at the
University of Maryland dealing with touchscreens. Some projects are
controlled experiments, the others are examples of applications where
the touchscreen was used successfully in innovative ways.
The first papers listed have already been published and are available
in journals and magazines, the ones in the second group are to be
published or technical reports. We will be happy to send you
a copy if you request it (send mail to sears@cs.umd.edu)
If you have questions about the projects... contact one the authors
listed in the paper [Andrew Sears (sears@cs.umd.edu) or of course me
Catherine Plaisant (plaisant@cs.umd.edu) and Ben Shneiderman
(ben@cs.umd.edu)]
Recently we also put together a video with several demos of
touchscreen applications (and other things like the already known pie
menus of Don Hopkins or a study of Table of Content browsers). I add
the announcement at the end of this message. If you are interested
contact me [plaisant@cs.umd.edu] (Unfortunately we have to charge $30 US
($35 US Overseas) for the video...)
Catherine Plaisant
Assistant Research Scientist
Human-Computer Interaction Laboratory
A.V. Williams Bldg. tel: (301) 405-2768
University of Maryland plaisant@cs.umd.edu
College Park, MD 20742, USA fax: (301) 405-6707
(-- et vous pouvez parler Francais si vous preferez! --)
--------------------------------------------------------------
Human-Computer Interaction Laboratory
HCIL PUBLICATIONS
about
TOUCHSCREENS
--------------------------------------------------------------
HCIL
A. V. Williams Building
University of Maryland
College Park, MD 20742
// PUBLISHED = already accessible //
--- Shneiderman, B., (March 1991), Touch screens now offer compelling
uses, IEEE Software 8, 2, (March 1991), 93-94, 107.
A brief review of the advantages of high precision touchscreens with
dragging and lift-off. Examples and screen prints show home
scheduling, message board, fingerpainting, and small touchscreen
keyboards. Suggestions for novel directions are offered.
--- Sears, A., and Shneiderman, B. (June, 1989), High precision
touchscreens: Design strategies and comparisons with a mouse.
Technical Report CS-TR-2268, CAR-TR-450. International Journal of
Man-Machine Interaction, 34, 4 (April, 1991).
Three studies were conducted comparing speed of performance,
error rates, and user preference ratings for three selection devices.
The devices tested were a touchscreen, a touchscreen with
stabilization (stabilization software filters and smooths raw data
from hardware), and a mouse. The task was the selection of
rectangular targets 1,4,16,32 pixels per side (0.4x0.6, 1.7x2.2,
6.9x9.0, 13.8x17.9 mm respectively). Touchscreen users were able to
point at single pixel targets, thereby countering widespread
expectations of poor touchscreen resolution. The results show no
difference in performance between the mouse and touchscreen for
targets ranging from 32 to 4 pixels per side. In addition,
stabilization significantly reduced the error rates for the
touchscreen when selecting small targets. These results imply that
touchscreens, when properly used, have attractive advantages in
selecting targets as small as 4 pixels per size (approximately
one-quarter of the size of a single character). Ideas for future
research are presented.
--- Plaisant, C., Shneiderman, B. and Battaglia J. (1990), Scheduling
home-control devices: A case study of the transition from the research
project to a product. Human Factors in Practice. December 1990,
7-12. Santa-Monica, CA: Computer Systems Technical Group, Human
Factors Society.
///Ask us a copy if you can't access this new magazine ///
This case study describes the transition from a research project
on scheduling home-control devices to a product integrated in an
existing home automation system. First we describe the research that
explored several designs to schedule devices over time periods ranging
from minutes to days: four designs were compared, three of them
prototyped and tested. One of the designs was selected for
implementation in the commercial system. We then categorize the
actions that were taken in order to improve and mold the prototype
design into an integrated product. Finally we report on an additional
study that emerged from the first one - the scheduling of periodic
events - and on the extensions of the scheduler interface design to
other aspects of home automation.
--- Potter, R.L., Weldon, L.J., and Shneiderman, B.,(May 1988), Improving
the accuracy of touch screens: An experimental evaluation of three
strategies. Proceeding of the Conference on Human Factors in Computing
Systems, Washington, DC, 1988, 27-32.
--- Potter, R., Berman, M., and Shneiderman, B. (Nov. 1988), An
experimental evaluation of three touchscreen strategies within a
hypertext database, Technical Report CS-TR-2141, CAR-TR-405,
International Journal of Human-Computer Interaction, 1(1) (1989),
41-52.
--- Sears, A., Kochavy, Y., and Shneiderman, B. (1989), Touchscreen
field specification for public access database queries: Let your
fingers do the walking. Proceedings of the ACM Computer Science
Conference (Feb. 1990).
Database query is becoming a common task in public access systems;
touchscreens can provide an appealing interface for such a system.
This paper explores three interfaces for constructing queries on
alphabetic field values with a touchscreen interface; including a
QWERTY keyboard, an Alphabetic keyboard, and a Reduced Input Data
Entry (RIDE) interface. The RIDE interface allows field values to be
entered with fewer "keystrokes" (touches) than either keyboard
while eliminating certain errors. In one test database, the RIDE
interface required 69% fewer keystrokes than either keyboard
interface.
--- Shneiderman, B., Brethauer, D., Plaisant, C., and Potter, R. (May
1989), The Hyperties electronic encyclopedia: An evaluation based on
three museum installations, Journal of the American Society for
Information Science, 40(3), 172-182.
// TO APPEAR //
-- Sears, A., Plaisant, C. and Shneiderman, B. (June 1990), A new era
for touchscreens: High precision, dragging icons and refined feedback.
Technical Report CAR-TR-506, CS-TR-2487. To appear in Hartson, R. and
Hix, D. ed., Advances in Human-Computer Interaction, Vol.3, Ablex
Publ., NJ.
While many input devices allow interfaces to be customized,
increased directness distinguishes touchscreens. Touchscreens are
easy to learn to use, fast, and result in low error rates when
interfaces are designed carefully. Many actions which are difficult
with a mouse, joystick, or keyboard are simple when using a
touchscreen. Making rapid selections at widely separated locations on
the screen, signing your name, dragging the hands of a clock in a
circular motion are all simple when using a touchscreen, but may be
awkward using other devices. This paper presents recent empirical
research which can provide a basis for theories of touchscreen usage.
We believe recent improvements warrant increased use of touchscreens.
--- Sears, A. (Sept. 1990), Improving touchscreen keyboards: Design
issues and a comparison with other devices. Technical Report
CAR-TR-515, CS-TR-2536. To appear in Interacting with Computers.
This study explored touchscreen keyboards using high precision
touchscreen strategies. Phase one evaluated three possible monitor
positions: 30, 45, and 75 degrees from horizontal. Results indicate
that the 75 degree angle, approximately the standard monitor position,
resulted in more fatigue and lower preference ratings. Phase two
collected touch bias and key size data for the 30 degree angle.
Subjects consistently touched below targets, and touched to the left
of targets on either side of the screen. Using these data, a
touchscreen keyboard was designed. Phase three compared this keyboard
with a mouse activated keyboard, and the standard QWERTY keyboard for
typing relatively short strings of 6, 19, and 44 characters. Results
indicate that users can type approximately 25 words per minute with
the touchscreen keyboard, compared to 17 wpm using the mouse, and 58
wpm when using the keyboard. Possible improvements to touchscreen
keyboards are suggested.
--- Plaisant, C.(Nov. 1990), Guide to Opportunities in Volunteer
Archaeology - Case study of the use of a hypertext system in a museum
exhibit. Technical Report CAR-TR-523, CS-TR-2559. To appear in Berk
E., ed. Hypertext/Hypermedia Handbook, McGraw-Hill Publ. (1991).
This case study shows how a hypertext system was used in a traveling
exhibit of the Smithsonian Institution. The database about
archaeology was constructed by a professor and students of the history
department of the University of Maryland. Regular updates of the
database were made for each new venue of the exhibit. Finally the
database was translated into French and automatically rebuilt to be
used in Canada. Helpful features of the hypertext system as well as
the difficulties encountered are described. System users were
observed in the museum and collected usage data was analyzed.
--- Plaisant, C., and Shneiderman, B. (November 1989), Scheduling
ON-OFF home control devices: Design issues and usability
evaluation of four touchscreen interfaces, Technical Report,
CS-TR-2352, CAR-TR-472. To appear in the International Journal of Man
Machine Studies.
This article describes four different user interfaces supporting scheduling two state (ON/OFF) devices over time periods ranging from minutes to days. The touchscreen-based user interfaces including a digital, 12-hour clock, 24-hour linear and 24-hour dial prototypes are described and compared on a feature by feature basis. An informal usability test with 14 subjects, feedback from more than 30 reviewers, and the flexibility to add functions favors the 24-hour linear version.
// TECH REPORTS //
--- Sears, A., Revis, D., Swatski, J., Crittenden, R. and Shneiderman
B. (April 1991), Investigating Touchscreen Typing: The effect of
keyboard size on typing speed. Technical Report CAR-TR-553,
CS-TR-2662.
This study investigated the effect keyboard size has on typing speed
and error rates for touchscreen keyboards. Four keyboard sizes were
investigated ranging from 24.5 cm to 6.8 cm wide (23% larger to 64%
smaller than standard keyboards). Results indicate that novices can
type approximately 9 words per minute (WPM) on the smallest keyboard
and 20 WPM on the largest. Users with moderate experience with the
keyboards improved to 21 WPM on the smallest keyboard and 32 WPM on
the largest. These results indicate that although slower, very small
touchscreen keyboards are possible and can be used for limited data
entry when the presence of a regular keyboard is not practical.
Results also indicate the increased importance of experience on these
smaller keyboards. Possible research directions are suggested.
--- Plaisant, C. and Wallace D. (Nov. 1990), Touchscreen toggle
switches: Push or slide? Design issues and usability study. Technical
report CAR-TR-521, CS-TR-2557.
This article describes six different touchscreen based toggle
switches allowing the control of two state (ON/OFF) devices. The user
interfaces, ranging from button type toggles to sliding toggles are
described and compared. A usability test with 15 subjects was
conducted. Error rates, user preferences and subjective satisfaction
ratings were collected. Results indicate that all the toggles
described here can be used with low error rates. The sliding toggles
were rated harder to use and were least preferred. Individual
differences in personal preference were shown to be very large. It
was also observed that users spontaneously or after one trial use a
sliding motion to activate a control showing a sliding affordance.
-----------------------------------------------------
VIDEO ANNOUNCEMENT
-----------------------------------------------------
UNIVERSITY OF MARYLAND
HUMAN-COMPUTER INTERACTION LABORATORY
VIDEO
"HCIL Open House 91 Videotape": a one hour tape containing reports and
demonstrations of HCIL projects:
1-Introduction:
Ben Shneiderman
2-Scheduling home control devices:
Catherine Plaisant and Ben Shneiderman
3-Touchscreen toggles:
Catherine Plaisant
4-A home automation system:
Reuel Launey from Custom Command Systems
Presented by Ben Shneiderman
5-PlayPenII: A novel fingerpainting program:
Andrew Sears and Ben Shneiderman
6-Touchscreen Keyboards:
Andrew Sears and Ben Shneiderman
7-Pie menus:
Don Hopkins
8-Three interfaces for browsing tables of contents:
Rick Chimera
Request for the tape (VHS-NTSC only) may be sent to Mildred Johnson,
HCIL, A.V. Williams Building, University of Maryland, College Park,
MD 20742. Submit a check for $30 ($35 for overseas) made out to the
University of Maryland (no purchase order or cash please).
[For questions about the video send mail to Plaisant@cs.umd.edu]
--
Catherine Plaisant
Human-Computer Interaction Laboratory
A.V. Williams Bldg. tel: (301) 405-2768sears@tove.cs.umd.edu (Andrew Sears) (06/14/91)
I'd like to suggest to anyone who is interested in references to touchscreen research that they look at the abstracts posted by Catherine Plaisant of HCIL (where I work) in article #76. These papers contain extensive references to papers by many other researchers (the New Era in Touchscreen Applications paper has the most references). This is actually in reply to the last three postings on touchscreens. First, I have used the SAW touchscreen from Elographics (z axis). I like this technology, but I wish they would stop saying that it provides 16 levels on the Z axis when they admit only 3 or 4 are useful. Some day it would be nice to use a touchscreen that allows many levels on a Z axis. Second, having the users hand obscure the screen can be a problem if the interface is not carefully designed. It is important to remember that an interface designed for a mouse may not be optimal for a touchscreen. Of course, the users hand will still cover part of the screen, but the negative impact of this can be reduced. There have been several comments about the issue of fatigue when using the touchscreen. I'd just like to restate the experiences I've had. We have a desk that simply lets the monitor be recessed into the desk at various angles. There is a place where users can rest their forearms in front of the monitor. Placing a normal monitor in this desk so the surface is 30 degrees from horizontal dramatically reduces fatigue and increases user preference. This desk is normal in all other aspects and the monitor used is also a standard monitor. (Sears, A. (1991). Improving Touchscreen Keyboards: Design issues and a comparison with other devices. To appear in Interacting with Computers) >>Some notebook computers will not >>have a keyboard but will rely solely on a touchscreen and pen input. > >Certainly this is self-consistent. But, my handwriting is hard to read, and >after a mere year of using text editors to enter the text of papers, I >gave up composing on paper entirely. I don't want to go back. >I have also lost a significant amount of hand fitness, which makes picking >up handwriting even more of a chore. We should really make a distinction between touchscreen and pen input. Most systems that do handwriting recognition require higher resolution than is offered by touchscreens. Sure some touchscreens can be used with a stylus, but not to recognize handwriting. Personally, I do not see touchscreens being used as the input device when extensive text must be entered, the keyboard is the appropriate device for this. However, in some situations, when limited data entry is necessary, a touchscreen only interface may be useful. > >>A number of touch screens do not actually require that their surface be >>touched but humans seem to love to jam their fingertips forward. > >This is because constrained selection is easier than unconstrained >selection. Using a 3D technique to select a 2D object is silly. >The tactile feedback is useful, also. > Selection of buttons can work very well on touchscreens. Appropriate feedback at the appropriate time can make this very easy to learn and use. Andrew ----------------------------------------------------------------------------- Andrew Sears sears@CS.umd.edu Human-Computer Interaction Laboratory University of Maryland, College Park, MD 20742 (301) 405-2725
mcgregor@hemlock.Atherton.COM (Scott McGregor) (06/15/91)
In article <RSW.91Jun13143719@tahiti.cs.brown.EDU>, rsw@cs.brown.EDU (Bob Weiner) writes: >>In article <6460@ns-mx.uiowa.edu> jones@pyrite.cs.uiowa.edu (Douglas W. >>Jones,201H MLH,3193350740,3193382879) writes: >>> 4) Touch panels aren't particularly accurate. Even if you use a modern >>> thin-film touch panel, there is a real problem with paralax. > Shouldn't flat screens reduce this? I don't think this is the cause of the parallax problem is that the angle between the your eyes and your extended arm (typically bent at elbow) is large, regardless of whether the screens are totally flat or not. However, in a video prepared by Ben Schneiderman and U Maryland in 1988, a technique was demonstrated that seemed to have significantly better resolution and avoided the parallax problem. They created a "sprite" (similar to the mouse arrow) which you moved around the touch screen by pointing. Now, interestingly enough, the sprite wasn't actually at the point directly closest to your finger or stylus, but just slightly above it. That way you could still see the small sprite even when your big finger was touching the display and visually covering a lot of screen area. Furthermore, because the sprite was small (just a few pixels) it was possible to point with greater precision than the typical 2x2 character positioning that is assume with traditional touchscreens. Furthermore, people could really take advantage of this precision in say drawing, etc. because while fingers are large, people in general have excellent precision control over their fine movements. Scott McGregor Atherton Technology
mcgregor@hemlock.Atherton.COM (Scott McGregor) (06/15/91)
In article <1991Jun13.164856.1006@news.arc.nasa.gov>, > Did anyone else notice that when Mac users get proficent, they stop using > the mouse/trackball and use the KEYBOARD! I think there is a message > here... I think so too. But I think many people get the wrong message. Some people conclude that because proficient users use the keyboard a lot that means that when designing a new application design it for a keyboard instead of a mouse. But this misses the message from above, namely that nonproficient users are attracted by, or prefer the mouse to get started. Since all novel products have a learning curve, this argues for trying UI techniques that may help people get started easily and with low psychological effort, even if another interface may help them work more speedily once they become acclimated. I think the above observation argues for more work on interfaces that help new users migrate to high proficiency (but harder to learn) UIs. Mostly this seems to be done with keyboard equivalents indicated in menus, but I think that there is some interesting work in prescient agents, and anticipatory software which watch what a user does and help recommend or guide them into more proficient usage modes. Scott McGregor Atherton Technology mcgregor@atherton.com
msb@sq.sq.com (Mark Brader) (06/17/91)
I never met an input device I liked as well as a keyboard, except for the two cases of specialized environments and of graphics/drawing. But that's just me. However, I'm particularly annoyed by a machine installed a few months ago in my bank branch. (Royal Bank of Canada, Yonge/Eglinton branch). ago in my branch of the Royal Bank of Canada. This machine takes the user's ATM card and account passbook, and prints any pending updates in the passbook [using a dot-matrix font :-(]. The device has a touchscreen and a numeric keypad. To verify the user's identity, it asks for a PIN, the same as an ATM does. This has to be entered on the numeric keypad. Then, after the user has used the touchscreen to choose which account to update, it asks the user for the most recent balance shown in the passbook; this is to provide a partial verification that it is the right passbook and open to the right page. It then displays a numeric keypad on the touchscreen and disables the real keypad! Sheesh. There is visual feedback, and I only have to type a few digits, but it's still quite irritating to be slowed down by having to use this method. (A detail: unlike some banks, the Royal requires you to use a decimal point on its machines. On ATMs, $150 is typed as "150.00" or as "150" plus the OK key, not as plain "150" or "15000". Similarly the passbook updater requires "150.00". But its numeric keypad, I believe, has no "." key. Was this the reason for the decision to force the user to use the touchscreen? Couldn't something else have been done about it, like getting numeric keypads *with* a "."?) -- Mark Brader "Actually, $150, to an educational institution, Toronto turns out to be about the same as a lower amount." utzoo!sq!msb, msb@sq.com -- Mark Horton This article is in the public domain.
shafer@skipper.dfrf.nasa.gov (Mary Shafer) (06/17/91)
In article <1991Jun13.235714.17297@cs.UAlberta.CA> cdshaw@cs.UAlberta.CA (Chris Shaw) writes: >In article rsw@cs.brown.EDU (Bob Weiner) writes: >>Mount the screen in a desk at a slight upward angle. >This means that you need a low-profile screen. A deep CRT won't make it, >because you can't sit at your desk with your legs stretched out. It also means that bifocal wearers are in trouble. They'll end up cocking their heads up to peer through the bottoms of their glasses and have incredible neck pain or they'll have to lean over the keyboard to look at the screen. -- Mary Shafer shafer@skipper.dfrf.nasa.gov ames!skipper.dfrf.nasa.gov!shafer NASA Ames Dryden Flight Research Facility, Edwards, CA Of course I don't speak for NASA "Turn to kill, not to engage." CDR Willie Driscoll
tsarver@andersen.uucp (Tom Sarver) (06/18/91)
In article <6460@ns-mx.uiowa.edu> jones@pyrite.cs.uiowa.edu (Douglas W. Jones,201H MLH,3193350740,3193382879) writes: >From article <8435@awdprime.UUCP>, by jon@kitty.austin.ibm.com (Werner): > >> Are there any papers written dealing with the use of touchscreens as an >> alternate input device in environments which don not have enough desk >> space for a keyboard or a mouse? > >I don't know of any papers, but as a long-term touch-panel user, I much >prefer mice, trackballs, or knobs on my keyboard. > >I used the U of Illinois Plato touch panels between 1973 and 1980, and >the big problems are: > > 1) You have to lift your hand up from the keyboard, perhaps a foot, > to touch the screen. This slows you down compared to horizontal > moves to a mouse. > > 2) No matter how good the anti-reflection coating on your screen is, > fingerprints tend to defeat it. If you've got a touch panel, you'll > need to wash it almost daily to keep the glare down. > > 3) If you have touch-intensive software, where you spend long periods > holding your hand up to the screen poking here and there, your arm > gets tired. I remember after some sessions debugging a particular > touch-intensive piece of computer aided instructional material, my > arm began to ache quite intensely. I've never experienced that kind > of reaction to "desktop pointers" like mice. > It appears that a touch-screen station would be designed in a completely different way than keyboard/mouse/screen combos are now. I suggest that a touch screen should have the monitor imbedded in the the desk pointing at the user with an adjustable angle to the desktop. This would be more natural in the way we deal with papers and pens and other items. (BTW, if you think about it, you don't want to judge an interface by the difficulties encountered by the developers. It's the users' opionons in which we're interested.) > 4) Touch panels aren't particularly accurate. Even if you use a modern > thin-film touch panel, there is a real problem with paralax. The > front of a CRT display is quite thick, and the push button size we > typically use with mice is small enough that it can be very hard to > find the right spot on the screen to touch to get a particular > button and not its surrounding area. The Iowa City Public Library > on-line card catalog has been touch screen based for a few years > now, and I've had numerous paralax problems with it, even thoug it > has nice big on-screen push buttons. > We should be able to use a stylus (sp?) or pen so that the computer is just one more thing we poke at. The optimal software would not require a keyboard at all. There should be some basic OCR which allows one to write letters (in print) which are replaced by text. Since it is interactive the OCR needs only about 80%-90% proficiency. This leans toward the attitude that the computer is simply a very flexible notepad. I realize I am basically describing a light pen interface, but the hardware is actually touch screen with the option of either stylus (hi-res input) or finger (lo-res input). > Doug Jones > jones@cs.uiowa.edu -- --Tom Sarver tsarver@andersen.com Andersen Consulting "Think straight; talk straight." 100 S. Wacker, Ste. 900, Chicago, IL 60606 (312) 507-4912 "If the Firm ever discovered my opinions, IT would summarily forget them."
jtchew@csa3.lbl.gov (JOSEPH T CHEW) (06/18/91)
>>> Are there any papers written dealing with the use of touchscreens as an >>> alternate input device in environments which don not have enough desk >>> space for a keyboard or a mouse? Don't know about papers, but touchscreens have appeared in garages (for diagnostic computers). It's a rude environment where, I suppose, mechanics waving their greasy fingers at the screen are preferable to trying to make a keyboard survivable. Joe "The pallid pimp of the dead-line/The enervate of the pen" --Rob't Service