This year’s theme is ‘Designing for a Sustainable World’. Last year over 200 events were held worldwide, and it will be similar this year – see http://www.worldusabilityday.org/en/events/previous/2009 for an extensive list. While many of the events are fairly straight plugs to advertise usability review or training services, there are a couple of events that caught my eye.

Most events require you to attend in person, so readers are only likely to be interested in stuff in their locality, but a few of the on-line events are worth a mention.

Building Smarter Cities looks like it could be an interesting on-line discussion.

There is a essay contest on the topic of “How can the User Experience Community support the future of sustainability?” You only need 100 to 300 words and you might win a kindle. I have not come up with an entry myself yet, but I will definitely be keen to read a few of the entries.

There is a webinar on the topic of Agile Design within the Usability Process.

There is an on-line panel discussion on ‘How Can a User Centred Approach Drive Sustainable Design?’, which would not have grabbed my attention until I noticed Ben Schneiderman was on the panel. I have read a lot of his stuff, so it might be interesting to see him in the (digital) flesh.

If any readers see any other events that deserve a mention, let me know – or if you attend/observe any of the on or off-line events I would be keen to hear any feedback.

Many of these symbols will not apply in an embedded system, but others are more global – like ‘help’.

It is a handy place to browse if you think that your embedded system is going to borrow some symbols from the desktop world. In many cases the embedded application will have less resolution available than a modern PC, and so it might be worth looking at older, simpler versions of that icon.

One of the delegates pointed out that such frustrations actually encourage people to use pirate copies of the movie, since the bootleggers usually remove the stuff they know no one wants. In other words they set higher usability standards than the original content creators.

While the issue of wasting the user’s time was point number ten in my talk at the conference, I want to discuss a different aspect of the DVD experience in this blog. The design of the DVD menu is usually a triumph of form over function, which means it is nice to look at, but not so nice to use. The graphic design is usually impressive, but the blaze of colors makes it almost impossible to see which item is currently highlighted, so you are not sure what you will get when you press the play (or OK) button. A simpler layout, and less background color and movement, would have given us a better user experience. The bigger the budget, the flashier the menu and the harder it is to use! I think it is derived from a movie culture of having a passive audience, and they are just not used to the idea that the viewer may have to do something, or make a decision.

Even worse than the main menu is the scene selection menu – which usually shows a set of scenes as thumbnails, numbered 1 to 5 and then a number of choices to see thumbnails for 6-10, 11-15, 16-20 etc. . Having two types of selection is confusing – I would much prefer to have one set of scenes and use the left/right to scroll them, so if there are too many thumbnails to fit on the screen, I scroll to the one I want. This scrolling would chronologically move through the film, and I would not have to guess whether I want to go to the 11-15 set or the 16-20 set, which is a guess I usually get wrong.

Of course what they really need to do is show the number of the scene when you pause the movie, so that the scene numbers have some utility – some DVD players allow you access to this number but only after another button press that most users are not aware of.

The problem that is not addressed in the design of the DVD experience is how to resume watching the movie that you stopped watching yesterday. If the scene number was displayed when the DVD is paused then you could remember it – instead you have to look at the thumbnails and try to guess if you have seen the scene before. Yes, some DVD players have a resume function, but this seems to depend on the user pressing some mad key combination within 2 seconds of putting the disk in and I have always failed to get this feature to behave pleasantly on any DVD player I have owned. It also does not solve the problem if you move the disk from the player in one room to another (if you have to ask “Why?” Then you do not have kids).

Maybe part of the problem is that the experience is designed in part by the DVD format standard and partly by the DVD movie creator and partly by the DVD player, and while they all managed to agree on video and audio formats and compression techniques, it is harder to agree on, or even define, the most desirable user experience.

While I was travelling to the conference I called in on a friend, and while I was there, he received delivery of a prototype of a remote control, called Amulet, which he is developing. It works with Window Media Center. The unique thing about this remote is that it can pick up voice commands and use them to play music, video or other content on the PC (which is normally connected to your TV for this type of use).

I thought that this gadget would be an ideal third party tool to make scene selection easier. Since you could speak the scene number instead of moving the highlight from scene to scene. Alas the scene selection thumbnails seems to be buried in a part of the system that does not have any easy external API. Basically the platform designers never really considered it to be a platform where a third party may want to sit something on top of it. This makes it difficult to present the chapters, using the thumbnails, in a way not intended by the original DVD designer.

It may be a bit harsh to blame the original format designers for this. Should they have foreseen that DVDs might be played on a range of devices from PCs to game consoles and not just in dedicated DVD players. Also an API that would allow third party software to control the menus would widen the range of input devices possible. It is always a challenge to predict the variety of ways in which future developers may want to use the formats and protocols being designed today.

One topic that got a mention at the “Current State of MicroElectronics” panel discussion was the increasing importance of low power. There was also a paper on tweaking motor control algorithms to reduce power consumption. Low power considerations now matter at all parts of the design. Reduced network traffic, means that a wireless link can spend more time turned off, reducing drain. A compiler optimization means that the processing is performed quicker, and now the device can spend more time in sleep mode, which consumes less current. It set me thinking about whether this has any influence on my own area of user interface design. We are all used to battery indicators, but in some applications there might be scope for providing more information. Some cars display the fuel consumption level, to encourage drivers to drive in ways that conserve energy (i.e. don’t accelerate so hard). Similar indicators on a GUI could influence the way the user configures a device, if battery life or power consumption is a concern. If I reduce the backlight brightness or turn down the music volume on an MP3 player, it would be nice to know what percentage change I have made to current consumption. I am told that turning on Bluetooth on my cell phone drains the battery, but there is no feedback on the device which allows me to confirm if this is the case. Current consumption could be graphically represented, with maybe some time averaging depending on the application.

A few months ago, in an ESD article (http://www.embedded.com/218101668) I bemoaned the fact that GUI library vendors do not differentiate between mouse events and touch events, and Qt (qt.nokia.com) was one of a number of products that I mentioned in that piece. At the Qt stand at the show I had a look at Qt 4.6 and was delighted to see that they not only added touch support, but handled multi-touch and have a mechanism for passing gestures to the application on OS’es that support gesture recognition.

QNX had no stand, but Garry Bleasdale, a field application engineer with QNX, gave a talk on GUI development. The talk focussed on Flash as a way of making user interfaces a lot sexier than you can with a typical GUI builder. QNX’s GUI builder, Photon, provides buttons, sliders and other graphical widgets, but could never offer the kind of slick animated GUI available with Flash. Of course you have to get Flash ported to your platform first – or hopefully someone has already ported it for you. Flash definitely gives you the opportunity to make your GUI unique, and it is often desirable to get away from the slightly Windows-ish GUI that you get with most GUI libraries’ buttons.

There was a “Current State of Embedded Systems” panel. Much of the discussion was a language war, where panel and audience kicked about ideas about why something better had not replaced C. For a while the discussion turned to operating systems. Jack Ganssle, at one point, blurted out “Linux Sucks” in the hope of invoking a riot – sometimes the Linux evangelists get rowdy at these events. Getting them all fired up probably does little for the technical content of the debate, but it makes it more fun. While I am unsure of the validity of the “Linux sucks” position, Jack made a more telling comment, that maybe Android as a more shrink-wrapped version of Linux, might take some of the pain out of integrating Linux into an embedded device. Will Android become the one-size-fits all Linux distro for consumer devices. Maybe a bit early to say, but definitely one to watch.

My other mission at the show was to investigate SPI interfaces to graphical LCD displays. I occasionally deal with a client who wants to add graphics to a design, but their preferred processor has no built in graphics controller, and no external address/data bus to allow an external graphics controller to be used. If the number of pixels is low (sub VGA resolution), then there are a number of modules available from distributors such as Arrow and Review Display Systems, who both had booths at the show. The SPI modules are basically a controller mounted on the display, sometimes with a touchscreen combined, and an SPI interface. The SPI is incredibly appealing to the hardware designers, since address/data bus issues disappear. I was warned however that these modules are usually designed for specific customers, usually for a cell phone. If the big volume customer looks for changes, then the small volume customer might be faced with the same mechanical or electronic changes. So anyone who is building a medium or low volume product, which has a long design life, should be very wary of this otherwise appealing design solution. This is the sort of stuff I learn at the shows, that you just can not find in datasheets and marketing brochures.

The idle state can lead to some design contradictions. If there is nothing to say, then leaving the text window blank seems like the most appropriate thing to do. Why give the user something to read (like ‘Status: Normal’) which gives them no information. However a blank display can make the device look as if it is off, which may be misleading.

If something has happened, like an alarm condition, then the user needs to read that and the message displayed in the idle state can be replaced – but most of the time there is no such alarm or other activity to display.

On one project we agreed that it would display the time-of-day. This is commonly done on home appliances such as cookers, or a hi-fi. I am not convinced that time-of-day is a good idea unless the time is being used for other parts of the application. Once you display the time, you are obliging the owner to adjust it for daylight savings. You are almost guaranteed that the time will be wrong the first time it is installed (if the delivery has crossed time-zones), so the first thing the owner finds himself doing is hunting through the manual trying to find out how to set the time, when this activity contributes nothing to the utility of the device.

There are cases where displaying the time is advisable, or even necessary. If the device timestamps events or executes actions at predefined times, then if the time were set incorrectly the device would be out of step with the real world. The only way to be sure the time is right it to make sure the user can see the time so they will notice it is wrong. However in devices where the time is not used for any of its functions I would avoid the extra work for designer and user introduced by displaying the time.

So if time-of-day is not the thing to display in the idle state, maybe a company name or slogan works. I am fond of this idea and it encourages brand recognition. But proceed with caution. I worked on one design where we decided to display the company name at the top of the display. It eventually got dropped because of pressure on space in the text window. The company has since changed names twice, and this would have led to awkward software updates, to prevent the product looking immediately out-of-date.

One current design is following the same route, but because there are number of other configurable items, the string displayed in the idle state can be set in configuration. In this particular application it is often re-branded when sold by distributors so it suits them to be able to display their own brand rather than that of the OEM.

Some systems lend themselves to displaying some internal state or measurement. I recently worked on a device connected to a CAN bus (communications network for automotive and industrial applications). Some of the CAN messages would cause conditions that were displayed on this device, but other messages were not. However it was always interesting to know how much activity was on the bus. If the user pressed a button to drive some part of the equipment, there was usually a burst of CAN traffic, and then the bus would revert to zero traffic. On the device with the LCD we displayed a ‘Traffic = N’ line, where N was the number of messages per second on the bus. This meant that even if you were not displaying a specific message about what was going on, you had a rough measurement of whether the bus was active. A bar-graph might have been more pleasing than a number, since this is only meant to be a rough indicator, but in this case the application was just for in-house factory test, and did not merit the extra development work

Other applications may have other interesting numbers. In business information systems they often refer to Key Performance Indicators (KPI) and seeing the value of these numbers at all times helps manager maintain a feel for how well the business is performing, eve if exact thresholds for those values are not established. In the same way an embedded device would display its most important number. A printer could say how many pages it printed in the last hour. A piece of factory test equipment could display the percentage of manufactured items that passed their test. If the percentage is always higher on a Tuesday, even if within acceptable bounds, then maybe there is a flaw in the system that could be tracked down.

Even if the information displayed does not contribute to analysis of the system, it conveys the impression that the device is either busy on the user’s behalf or ready to obey any command received. This will encourage the warm-fuzzy feeling that the device is eager to please.

All o f the employee records existed in a database. As we added cards to the system, the long and unwieldy swipe card number had to be entered manually into the employee’s record to create the mapping. As with any long-number entry, there is a risk that the number was entered incorrectly. Checksums within the serial number detected some faults but it was still not very satisfactory. And if the mistake was not discovered immediately, it led to hassle for the employee and supervisor the first time the card was used.

As we thought through this challenge, one option would have been to add a card reader to the server, or the PC accessing the server, and allow a card to be swiped instead of typing in the number. This added a number of unwelcome challenges. This reader would be different from the already installed readers since the communications link was different. The server was updated via the web, so you could not be sure where the user would be located, and restricting them to one location or PC would be troublesome.

Many solutions look so obvious after the fact and this was one of those cases. We eventually realized that the scenario where a card is unrecognised also provided the ideal opportunity to enter the correct user name.

So when the card is not recognised, instead of simply rejecting the user, the supervisor has the opportunity of picking a name from a list of employees, and the mapping from card number to employee is then created. This solution requires no extra hardware. The supervisor no longer has to type in long error prone numbers. The card can be swiped at any location, so when a new employee receives his card he simply goes to his nearest access point, and over the phone, tells the supervisor that he is about to swipe for the first time. The swipe is unrecognised, and the supervisor sees the new serial number, and its location, and links it to the appropriate employee.

This is a case of applying a principle called equal opportunity. It means that something that was delivered as output to the user can be turned around and used as input. This means that the user never has to enter the original data, since they received that data as output. Another example would be receiving a call on your cell phone from an unrecognised number, and being allowed to add it as a contact without having to type in the number all over again.

My online tutorial on equal opportunity provides a number of other examples of this useful technique:
http://www.panelsoft.com/tut_equal/index.htm

Consider a call center routing phone calls to a band of support or sales staff. Once the call routing is computerized, it is possible to measure the exact duration of each call, the time before a call is picked up and the amount of time between each call. These numbers can be used to measure productivity of employees. Once that productivity can be measured then many steps can be taken to increase it, such as linking pay with the percentage of a person’s time they spend on the phone. A case can be made that such measurements make the work place more pressurized, less pleasant, and might occasionally cause the most talented employees to seek employment elsewhere. That is a discussion on quasi-ethical issues that I am not interested in addressing here – the main point is that the measurements, which are a side effect of the call routing system can have a profound effect on the control of the system.

In other cases the measurement is not an incidental by-product, but the core purpose of the system. In medical devices, many innovations have been in the area of providing real time measurements of attributes that had previously been only occasionally measureable. Pulse oximeters give real time feedback on blood oxygenation levels. Previously a blood test was required, and this limited the number of samples that could be taken, and by the time the sample data came back from the lab, the patient condition could have changed. Modern respiratory therapists can make minor adjustments to a patient’s lung ventilator or to their medication, and then observe second-by-second the impact of the adjustment. It even opens up the possibility that the control loop could be closed by automatically adjusting lung ventilator parameters’ in response to changes in blood oxygenation levels. This has been implemented in experimental cases, but is not a mainstream solution.

At one point in my career I thought that the cutting edge of medical device development was working on therapeutic devices that delivered treatment to the patient, but I now realize that measurement can have just as big an impact on patient outcome. If doctor’s decisions are based on guesswork rather than raw data, then they are going to make less precise diagnosis.

Another area that has been revolutionized by measurement is running. In the past few years, consumer devices which tell you how far and how fast you run have come to market and proved extremely popular. Some are based on a foot sensor that measures how many paces you have taken, and others are based on GPS technology to measure the distance and route of the run. This is not just a replacement of a stopwatch – because the feedback is real time during the run, these devices can provide a motivating influence that is almost as good as having a running companion who is always a couple of seconds quicker than you.

One of the big advantages of using a gym (which I do not visit often enough, but that is another story), is that most activities are precisely measurable. If I am on the treadmill for 20 minutes, it can tell me precisely how far I ran and how fast. If I return to the gym tomorrow (well OK – next week), I can try to equal or better that run, which is a huge motivational factor. Even the gym activities that do not involve electronics allow me this precision of recording. The number of chin-ups or the weight that I bench press are numbers that are easy to record.

Road running always contains a vagueness that does not happen in the gym. Unless I run precisely the same route, I cannot compare times. Even with the same route, it is difficult to know how I am performing while I am on the run. I want real-time feedback, not just a result at the end – too late to motivate me to do a final sprint. A system that measures my pace as I run, and tells me whether I am faster or slower than my target speed revolutionizes road running. I can now pick any road and just go.

It is interesting to note a couple of the differences between the two main technologies. If you use a shoe sensor then it requires calibration to match your typical stride length. A GPS based system avoids this issue and also offers the advantage that it can record the actual route and later superimpose it on a map when the route data is downloaded to your PC.

The Nike+ system is a collaboration between Nike and Apple. At first glance I was surprised that Apple did not opt for the GPS solution. They are the kings of simplicity, and would have wanted to avoid the calibration step. While I am not sure what the rational was, a case could have been made that GPS raised other complexity issues – battery life means that you have to remember to charge the device between runs – at least that is true for the Garmin wrist-watch based devices. While GPS adds lots of extra information because it knows the route, it could be argues that most of that information is superfluous – the runner just wants to know how far and how fast. So maybe their rational was to choose to measure the things that help motivate the runner, but avoid flooding them with so much data that only the statistics junkie is interested.

There is a good article on the motivational effect of the Nike+ at http://www.wired.com/medtech/health/magazine/17-07/lbnp_nike

I also wondered about the effect of a shoe sensor that might have accuracy issues as terrain, weather and fitness levels varied. It then struck me that the accuracy would be rarely tested and so a few percent of an error would go unnoticed by the runner. If you are trying to break your personal best for five miles and your monitoring device tells you that you have improved by ten seconds, when in fact you have improved by 5 seconds, then you will not realize this. The important thing is that the motivational effect of seeing an improvement is still there. Accuracy only matters if you are comparing the results to some reference, and these devices are not used to record world records, so no one will really care.

Adding measurement and recording to a device can also introduce a bond between the device and owner, which has advantages in terms of marketing – the owner feels the device is like a pet dog that actually knows the owner. It has a disadvantage for the owner that it can become impossible to share the device. If I borrow my wife’s Garmin 405 to go for a run, it cannot tell the difference between my run and the ones my wife has done, and so her weekly mileage stats will be messed up. They could have incorporated a multiple-user feature, but that adds complexity, and I guess the marketing people figured it might also reduce sales. They would obviously prefer that each runner bought their own rather than have one device shared between two or more runners.

Have a look at your own designs and see if there are opportunities for game-changing measurements that will alter the way your system motivates the user.

Then I noticed that the tone of the key beep when entering normal mode was slightly different than the key beep when entering any other mode. The interface designer was giving me an easy way to know when I had reached the end of the list. So now, rather than watching each mode appear on the display, I press the button quite quickly and listen for the button beep to change.

I have used other devices that have different tones to convey different messages, but they rarely succeed because it is too tricky to remember what each tone represents. There are some ways to encode meaning into sounds, sometimes humorously called ‘earcons’ ! A rising tone suggests success or happiness, while a descending tone implies the opposite.

Beeps can get closer together to imply that some threshold is about to be met. Anti-bump sensors in cars can provide these beeps while reversing. Note that the driver can not usually map the spacing of the beeps to the distance from the object behind. However the driver can judge the spacing of the beeps relative to the spacing a second earlier, so he knows he is getting closer. This changing sound also has a natural limit as the reduction in the gap between beeps eventually leads to a constant tone implying that collision is imminent, or perhaps has already occurred.

A much less critical application is a kid’s music keyboard. We have one at home with five volume levels. When you turn the device on it always defaults to five – the loudest. It is always easier to convince a kid to turn up the music than to turn it down, so why did they not default to a quieter volume? An even better solution would be to remember the last used volume, but that might have a cost impact since some non-volatile storage would be required. Without that ideal option, try to pick the volume defaults to be the least disruptive.

These scattered examples of the use of sounds in the user interface might influence your thinking the next time you add a beep.

One common assumption that your system is the central focus of the user’s attention. That leads to the assumption that if your device is making an ‘urgent’ noise then it will be attended to quickly. This violates another rule, that I often refer to, that states that the designer should always assume that the user is very busy. While you are designing one piece of medical equipment, it is easy to forget that the user may be responsible for thirty pieces of equipment spread across six patients. When your device starts beeping urgently, it may mean that a patient needs urgent attention, or it might mean that the machine is sitting at the side of the room waiting to be used, and it is not interacting with a patient in any way. So for urgent noises, it is important to investigate use-cases of the worst case, most dangerous, scenario, but it is also important to investigate the most benign case to find out if the harmless case is going to lead to nuisance noises.

Another common decision is to sound a buzzer if the device is stuck in reset, or in some ‘not working properly’ mode. I recently worked on an after-market automotive device that did this. If some configuration parameters were not set up right, then the device would beep constantly. It seemed reasonable, since you never wanted to drive down the road with the wrong configuration parameters. The problem was that the device would often be like this in the workshop while the vehicle had wiring installed. While the vehicle was being worked on, no one cared about the configuration, but the noise drove everyone nuts – they used to ring me up rather than e-mail me just so I would hear how annoying the background noise was so that I would add an override feature.

You should always give some thought to whether noises can be silenced for these special cases. For the service guys, the ideal thing would be a simple dip switch to turn off the buzzer, but of course the danger with that sort of measure is that it would be left turned off when the device is shipped (or a user would turn it off) and then the buzzer would be disabled in the field. So you have to find a balance between ‘easy to override’ and ‘hard to accidentally override’. The solutions tend to be application specific.

If the user can not override the sound, then it can lead to undesired behaviour.Consider a pasanger seat with a weight sensor, that will beep if the vehicle moves while the seat belt is open. Now a driver who regularly leaves a bag of shopping on the passanger seat gets beeped at even though there is no passanger present – just a bag of groceries that weight enough to be a small person. So the driver plugs the seat belt in and leaves it that way permanently, just to make sure the beep does not happen. Of course this makes it more difficult for a real passanger to put on the belt on the occasions when this driver has a passanger, and it might even discourage this passanger from using the belt at all, which is the opposite of the original design intention. If the original warning sound been only temporary and more subtle then the driver may not have felt obliged to work around it, and so the problem might have been avoided. Again there is a trade of between making the sound so annoying that the user can not ignore it, and allowing for the case where that sound is actually a false alarm.

When designing a sound, always consider whether it is just for the ears of the user, of if other will hear. If you have a ‘failure sound’ (usually implied by a descending tone), when the user presses an illegal key, then the people near to the user will hear it and get the impression that the user is doing badly (if the user is a doctor, and the patient can hear the ‘wrong key’ noise then that can reduce the patient’s confidence in the doctor !). No user will thank you for announcing to the world that they pressed the wrong button, and these users will quickly want to silence the device. Having an easy to access mute or volume facility is vital for any noise-making device. Beeps that might be very subtle in noisy lab environment may be deafening in a library.

For the urgent noises that you might not want to volume control, consider having long silences between the beeps. If a noise is too intrusive, then the user’s priority is to silence the noise, and not to solve the problem. In medical devices I often see staff silence an alarm before they make any attempt to see the alarm message or to asses the patient. It is obvious that their first thought was ‘How do I stop the noise- it is driving me nuts’ when their first thought should be ‘What is the patient care issue that needs to be addressed’. Design noises to inform the user, not to bully them into responding.

My next post will point out some particularly bad uses of sound, and some particularly good ones. In the mean time, if you have any examples of your own, let me know.

On one project we had a customer complain about certain features that they wanted to work during low-power mode. With a small bit of effort the engineers added some configuration flags to turn on some outputs that were normally off during low-power mode. The customer received the update, but was still not happy. More flags and features were enabled but still no success.

The reason we were failing to satisfy the customer is that we were interpreting the term ‘low-power’ in the way we had defined it internally within the team. The processor had a low power mode, where the main software loop was not running, and the processor only woke up occasionally. However the customer had no understanding of CPU cycles and the like, in fact the customer did not know or care that there was a processor in the product. To the customer, ‘low-power’ meant that the LEDs on the front of the box were not lit, so it looked like it had been turned ‘off’, in some sense.

We finally satisfied the customer by providing a button that turned off a set list of outputs and turning off the LEDs on the front panel. The LEDs remained off until there was some further interaction with the device. The device never actually entered ‘low-power’ mode (as the engineers interpreted it). This was fine as the outputs that consumed most of the current, were turned off. In terms of current consumption, the difference between the processor running its full loop or going to ‘low-power’ mode was negligible.

So the customer continued to call it ‘low-power mode’ whenever we turned the LEDs off. Ideally we should have come up with another term for it, since it was bound to lead to some confusion later. While you do not want to take a George Orwell style control of your customers thinking by dictating what words they are and are not allowed to use, resolving ambiguities will ease the path for everyone.

So the next time a customer uses a term that you engineers have very strictly defined, stop and think about whether that is the same definition that is in the customer’s head.