THE GRAPHICAL USER INTERFACE was a relative latecomer to portable computers, but it’s here, it’s pretty, and it requires a pointing device. The portable alternatives to the desktop mouse are varied and creative, and sometimes even successful. But that depends upon how success is judged--there are plenty of competing criteria. As portables get smaller, real estate is more and more of a problem. And many hours of usability research have yet to come up with one perfect and perfectly comfortable solution.
From the pea-sized model on Panasonic’s notebook series to the large, centered unit on the old Apple PowerBook, portable trackballs show the greatest variety in placement and design. Although pointing accuracy is enhanced by software interpretation of your physical manipulation, you still need something physical to manipulate. Which is why the size of the ball itself is so important. A rash of tiny trackballs infected a recent wave of notebook computers, causing a backlash of user complaints. Not only was the rolling surface too small, but it also picked up oil and grime from the fingers, attracting dust and clogging the internal mechanisms. All trackballs need regular cleaning, but these needed to be cleaned only after a couple of hours of comprehensive use.
Tiny trackballs persist in machines by Dell and Compaq, where they’re found on the right side of the keyboard near the spacebar (Compaq also has placed a trackball beside the screen). NEC’s Versa series sports a small trackball perpendicular to the spacebar, restricting use to the thumb but placing the roller squarely beneath the thumb’s center, which does the most precise positioning. Gateway puts a small trackball on a slide-out drawer below the spacebar, which adds another moving part to the assembly.
Large trackballs centered in the palmrest are by far the most popular, appearing in such notebooks as the Acer AcerNote series, AT&T’s Globalyst 200, Zenith’s Noteflex series and machines by Ambra, Austin, and Ergo, among many others. Acer’s trackball is removable, allowing easy substitutions--a good idea considering some of the newer gadgets just appearing.
Hit the Road, Track
Some of those newcomers are just trackballs in different guises. Microsoft’s Ballpoint mouse, for example, and Logitech’s Trackman Portable are fit-in-your-palm trackball devices that
hang off the side of a portable computer. You sacrifice none of the notebook’s smallness, you’re not tied into any given device, and you have the freedom to place the gadget where you wish, so even the orneriest lefty should be pleased. Some manufacturers, like Texas Instruments and Toshiba, have gone straight to that solution, offering Ballpoints as factory equipment.
The large Ballpoint trackball is cradled in a half-circle shell that clips to the rim of your notebook computer, with several different-sized clips available to cover all possible keyboards--including the keyboard with your desktop machine. With your hand comfortably draped around it, the buttons are also easy to reach. And the clip has been streamlined to allow you to close the lid of your notebook, which wasn’t possible with the first Ballpoint design.
Logitech is trying to go Microsoft one better. Where the Trackman Portable is pretty much a Ballpoint knock-off, the new Trackman Voyager is a study in clever industrial design. Although the trackball itself is a little smaller than the Ballpoint’s, it’s flanked by three buttons--one of which can be programmed to be the equivalent of a double-click--and the unit is built to clip to the front or either side of the notebook. The sleek little gadget has a cover that can be fitted to one side of the Voyager to turn it into a comfortable desktop trackball. Or it can be cradled in one hand to facilitate presentations, like Interlink’s ProPoint (see below).
The Ballpoint and Trackman models still need to be cleaned, and a good clamp is required to keep them firmly nestled against the notebook; too much vibration aggravates a shaky connection. Depending upon your attitude toward ergonomics, these units may be preferable to center-mounted trackballs because they force you to move your mouse hand away from the keyboard (see Sidebar).
If you want to stay completely away from the keyboard, HandyKey’s all-in-one one-handed mouse and keyboard combo, the Twiddler, requires intensive learning to take advantage of all its features. Its 12 front buttons (operated by four fingers) and six rear buttons (operated by the thumb) work together to produce all possible letter and number and function key combinations. It sounds daunting, but it’s possible to gain facility with the Twiddler after just a few hours of study and practice. The unit is secured to your hand with a Velcro strap, and its most fascinating feature is its floating cursor control, achieved by tilting the unit. It’s similar to operating a joystick, but you do it in mid-air. The Twiddler can be used in either hand, and even can be plugged into a desktop computer without disabling your regular keyboard.
One of the strangest-looking pointers proves to be one of the most efficient. In adding a pointing device to its OmniBook series of subnotebooks, Hewlett Packard opted for a pop-out mouse (called the “pop-out mouse”) that tucks into the far right corner of the keyboard and emerges, propelled by a spring, when a button near the screen is pressed. The mouse itself is the size of a cigarette lighter, with two buttons at the front, where it’s also hinged horizontally to allow the back to pop up and provide palm support.
What does the actual work is a controller buried beneath the keyboard that’s attached to the mouse by way of a flexible plastic wand that looks like a popsicle stick. The combination allows the mouse to work in a very limited amount of space--a tray table is no problem--or even hang in the air if you cradle it in your hand to move it.
It’s limited to right-handed use, and the OmniBook has no PS/2 port to support the newer add-on pointing devices. But within that limitation, the pop-out mouse does a very good job of emulating a desktop mouse, so that the only finger re-training required is getting used to a smaller device.
On a Different Track
IBM solved the real estate problem condominium-style by adding its pointing device to an existing structure. The TrackPoint--a pencil eraser-like stub--sits in a hollow carved from the edges of the G, H, and B keys, emerging unobtrusively enough to not interfere with normal typing but to respond easily to a fingertip. Two mouse buttons are centered on the front of the keyboard, and the buttons can be configured as primary and secondary as desired. In other words, it’s a completely ambidextrous device.
It’s a simple unit to learn. Because it’s essentially a miniaturized joystick, your finger needs to remember the amount of throw necessary to move the cursor a given distance; that effort is helped by the acceleration built into the device. There’s a little initial resistance, but as you continue to push, the cursor picks up speed. As you relax pressure, it brakes to a stop.
Not much actual motion is involved, so you don’t get the tactile sense of covering as much distance as a mouse or even trackball provides. But the TrackPoint’s designers counter by damning the standard with faint praise: “The unlikely mouse design is a surprisingly good pointing device, proving that man can draw with a rock,” reads an IBM white paper. The TrackPoint evolved slowly; among the rejected design ideas was a keyboard that would wiggle back and forth to move the cursor. It has fewer moving parts than a trackball, and it’s operated by a fingertip, which gives much more precise control than the thumb.
For the word processing tasks of moving blocks of text, the TrackPoint is faster than a mouse or trackball. The hands never have to leave typing position, so it’s possible to move that much more quickly between typing and cursor-jockeying. Whether that’s entirely desirable is contested in repetitive stress studies.
It’s proving to be a popular design. Licensed TrackPoint devices are also found in Texas Instruments’ TravelMate M series of notebooks and the WinBook XP; imitations are used by Toshiba’s Portégé and NEC’s Versa S subnotebooks. If you’re an IBM user with a fondness for the TrackPoint, the company also offers it in a desktop keyboard.
The JMouse takes an unusual approach to the idea of embedding a pointing device in the keyboard--it piggybacks mouse functionality on the J key, where a touch-typist’s right index finger falls. Press and release the key and you type a letter; press and hold the key and swivel it slightly and it moves the cursor. For one-handed operation, the spacebar serves as the primary button; that’s duplicated by the F, with D as the secondary button and S as button number three. G is the equivalent of a double-click, and many of the other keys on the left side of the keyboard call up common Windows editing features when the J key is depressed.
And that tells you what this pointer is all about: it’s a writer’s tool. Touch typists and skilled four-finger artists alike will enjoy the speed with which block-oriented text changes can be made--because you never have to lift your hands from the keyboard. It has one of the more difficult learning curves, although distinguishing a J from a mouse movement is about the least of the problems--good algorithms that determine the typist’s intention take care of that.
What requires the most training is learning to substitute keyboard keys for mouse buttons. If you’re mildly dyslexic, as I am, a game of Minesweeper can be disastrous at first. Once that curve is crested, however--and it should take only a couple of hours of effort--the clicks and commands fall into place nicely.
At Your Fingertips
At first glance, there seems to be something missing from Apple’s new PowerBook 500 series. Where the trackball used to be is just a smooth surface the size of a matchbook cover. It’s called a Trackpad, and your finger becomes, in effect, the mouse. Touch the pad lightly and the cursor follows your finger.
It’s the same as an add-on device called the Glidepoint, from Cirque Corp., although neither company will admit to being associated with the one another owing, probably, to some Draconian licensing deal.
Probably the most intuitive of all devices tested for this article, the Glidepoint sports a pair of buttons at the bottom of the pad, although a primary button click can also be accomplished simply by tapping the pad--twice for a double-click. Interestingly, many users first encountering the GlidePoint simply assume that that’s so, testimony to a good design idea.
Although the pad seems undersized for its purpose, it works impressively well. Fine cursor movement only requires a slight roll of the finger, and the accompanying software allows for the typical niceties of acceleration and double click speed. This is the first pointing device that actually calls upon you to point, and there’s a very natural feel about using the index finger to place a cursor. Cirque hopes to license the product into other machines, which shouldn’t be a tough sell.
Diehard desktop mouse enthusiasts have two options: learn the keyboard equivalents of mouse-driven commands, or use the Mouse Slide from Creative Computer Associates. It’s a plexiglass assembly that Velcros to the bottom of your notebook computer and provides a pull-out mouse pad that’s surprisingly sturdy and roomy. Although it works well on an airplane tray, it’s even better on your own lap, giving a breakfast-in-bed sense to your work. And it only adds 13 ounces to the total weight of your machine.
It’s the only device that probably won’t require some finger retraining, although such retraining is quickly transparent and shouldn’t be a major consideration when choosing a portable pointing device. Other features of a notebook computer tend to outweigh the pointer when you’re deciding what to buy, and a few minutes of fiddling with any pointer in a retail showroom is never enough. What’s most comforting is that more and more attractive add-ons are available to compensate for unpleasant original equipment; tuck one of them in your pocket and you’re ready to face anybody’s machine.
Sidebar: Pointing Device Ergonomics
HOW EFFECTIVE is a particular pointing device? Bryce Rutter has been studying the health considerations and general usefulness of the various options and finds no easy-to-name solution. “A number of factors influence effectiveness,” he says. “Frequency of use and
nature of the work being done are usually tied in together. Cost and ergonomics are also considerations. If you look at some of the small trackballs, especially those mounted on the screen, you’ll see that over time the trackball is not that effective. You have to support the dead weight of your arm as you use the it, and it requires you to twist your wrist uncomfortably to click the buttons.”
Ergonomics is the study of the relationship between humans and machines, a relationship that gets a lot of attention thanks to a rise in computer-induced injuries. Dr. Rutter, who holds degrees in industrial design and kinesiology, is a principal of Metaphase Design Group, a consultant firm near St. Louis that specializes in design research and ergonomics in the high- technology and handheld areas.
“The way you use a device also includes where it’s used,” he says. “If you’re using it on something moving, like a vibrating train or airplane, and you’re trying to manage a trackball, that’s even more stress producing.” He argues against the small trackballs because too much motion is needed to produce cursor movement. “Because of that, the dynamics don’t work out. You can adjust the control so that a minor movement of the ball will shoot the cursor farther, but then it becomes a superfine motor task.”
Small trackballs also lack a good surface contact area. “It’s more of a point load as opposed to a distributed load. Not in terms of comfort, but in getting a good coefficient of friction with the ball.” And it’s not just the trackball family that comes under his scrutiny. “There are problems with devices that are embedded in the keyboard, such as the TrackPoint. People with long fingernails or large-diameter fingers easily hit the adjacent keys. Also, having a device near the keyboard like that means that your hands never leave the typing area. That’s not good. What you want is a computer interface that promotes a little bit of movement. This is also true of centrally-located trackballs. What you want to do is get your hands off to the side and open up your rib cage. Or at least move your hand back and forth. Trackballs like the Microsoft Ballpoint and Logitech Trackman that clip on the side get a stronger vote from us.”
TrackPoint and JMouse enthusiasts refer to studies that show increased productivity with these near-the-keyboard pointers; not surprisingly, Rutter challenges those results, saying that they don’t consider eventual stress and fatigue. “You’re nailing the user into one posture to use a machine, when it’s better to promote a minor of degree of variability. Different individuals have different body architecture, and require flexibility to find a comfort space.”
And what is the period of time it takes for any problems to show? “There are so many variables that we can’t nail down one answer,” says Rutter. “Variables include body size, age, and physical state. Just for a ballpark figure, if you have a device that’s up beside the screen, as you start to use it with typical Windows frequency, you’ll probably start to get tired after an hour or two. With a centrally mounted device, it will take a longer time to feel the effects--so that solution is more acceptable, because it takes longer to manifest. Of course, you can escape any of these effects if you use it for only 20 minutes, then go and do something else for a while.”
Sidebar: Up in the Air
One of the selling points of built-in pointing devices is cordlessness. While only a minor annoyance when setting up your notebook, they have incurred the wrath of some airline employees and you’ll hear of very inconsistent policies regarding add-on pointers.
It seems that some navigational problems last year were blamed, rightly or not, on a portable computer, and the Federal Aviation Administration came up with regulation 19.21, which lets the airplane operators ban any devices they think can cause radio interference. Anything electronic emits radio waves, although the FCC requires computers to fall within strictly-imposed limits. Nevertheless, carriers have gone all the way from requiring passengers to shut down the computer during take-off and landing to forbidding computer use at the gate and banning all peripherals equipment--add-on pointers included.
All airlines allow use of portables once the plane is above 10,000 feet, and none of them wants you to use it during the start and finish of your journey. Pointing devices with attached cords are cited by some airlines as potential interference devices (the cord, you see, acts as a transmitter), although this obviously isn’t the case with cords attached to headphones handed out for in-flight entertainment.
American Airlines forbids corded mice because someone might trip over the thing, but infra-red mice ore okay. Generally speaking, you’ll have more trouble with the computer itself than with an add-on pointing device, but be sure to ask about the policy before buying your ticket. And keep in mind that the policies are all so variable that the crew on your return trip may make different demands than the one on the way out.
For the record, a 1993 study by PC/Computing magazine found that an FM radio emitted more radio frequency than dozens of portable computers, and even that amount was hardly dangerous. Which only reinforces Michael Flanders’ observation that “if God had intended us to fly, He would never have given us the railways.”
– Mobile Office, November 1994