Pictures of the Future      Spring 2008

A procedure is being performed to correct a case of atrial fibrillation. The doctor punctures the patient’s femoral artery and slides a thin catheter into the opening, his fingers covered in sterile gloves. He feels for the joystick on the control panel, also kept sterile beneath a covering of film, carefully guides the C-arm of the Axiom Artis medical imaging system—an interventional cardiology system that makes blood vessels visible—around the patient, and presses the foot pedal to make an X-ray fluoroscopic image. With a glance at the monitor hanging next to him, the doctor sees how the catheter is moving through the artery. Slowly, he slides it into the heart. The doctor and his team work with great concentration for two hours until the afflicted region is treated with a high-frequency current and the heart is beating normally again. No sooner have they finished than the next patient is wheeled in.

So it goes for eight hours—all while a quiet observer in the background documents everything with a video camera. The observer is Philipp Quaet-Faslem, a usability specialist from Siemens Corporate Technology (CT) in Munich. Quaet-Faslem’s job is to watch how doctors and their assistants work with medical equipment. His goal, and that of his colleagues in 12 hospitals in the U.S. and Germany, is to find out what irks doctors while operating devices. They look for possible operating errors, for muted curses uttered by a doctor who reaches for the wrong joystick, trips over cables, or awkwardly cranes his neck to concentrate on monitors that are suspended uncomfortably high.

"Anything that distracts the medical team is bad," explains Quaet-Faslem. "They shouldn’t have to think very long about how to operate equipment. They should be able to understand and use the controls intuitively." Achieving that seemingly straightforward goal is, however, a time-consuming job for usability specialists like Quaet-Faslem.

"We worked on improving the operation of the Axiom Artis system for over a year," says Dr. Judith Regn, head of Ease of Use at Siemens Medical Solutions in Forchheim, Germany. Many hours of video material were evaluated; improve­ments were drawn up in sketches and implemented in prototypes. In the lab, medical procedures were tested with product managers, application specialists and, later, with the customer—all with the aim of making the system adapt to the user and not vice-versa.

Workflow analysts uncovered weak points, such as in the control panel at the patient table. "Many of the elements, such as joysticks and knobs, looked very similar and were easy to confuse. This is further complicated by the fact that the panel has to be covered with a sterile plastic film during procedures," says Quaet-Faslem. It was his idea to give the control levers different shapes. As a result, the control elements now look markedly different from one another. The doctor thus knows at a glance which knobs are used for which tasks.

For the Artis zeego and Artis zee family, which were presented in November 2007 at the Radiology Society of North America, usability specialists developed a special robotic control module for the C-arm. The module allows a doctor to move the arm with six degrees of freedom. Field tests are now underway.

Specialists also optimized a touchscreen that projected out of the control console—a potential impediment for doctors. "We built it into the panel in reduced form and replaced the old display messages with easy-to-understand symbols and characters," reports Quaet-Faslem. That was made possible by changing the underlying navigation software. He considers this kind of soft­ware ergonomics to be an important new trend, in addition to standard concerns with knobs, switches, and the like. "In the case of the Artis system, software accounts for about half of the development cost. The reason for this is that in the future these medical imaging systems will be increasingly linked online with other medical equipment, making radiology workflow more seamless and efficient," explains Quaet-Faslem. For example, results from examinations can be immediately analyzed by other systems, allowing critical decisions to be made more quickly.

More Icons. In addition to optimizing the usability of medical systems, experts are also working on ergonomics in other fields. For instance, in rail technology, Siemens’ Mobility Division is developing a train control system for a new generation of commuter trains in which, among other things, the display soft­ware for the driver benefits from a simpler architecture. "The trend is away from text-laden displays and hierarchically organized tree structures toward a flatter hierarchy with more icons," says CT usability expert Martin Kessner. The monitor at first shows the train driver only the information he or she needs for a normal trip. Drivers have quick, direct access to systems such as brakes and doors. And in the event of a fault, the software not only shows the location of a problem but also provides tips on how to remedy it at the touch of a finger.

A possible outcome of poor user guidance was made plain on November 4, 2006, when the electrical grid collapsed in various parts of Europe. Fifteen million people were without power for almost two hours. A report from the power company involved stated that a power system control center in northern Germany, working under deadline pressure, failed to use all the available technical tools for a comprehensive assessment of the situation. Werner Höfler, a usability engineer at Power Distribution, has a simple explanation: "When a person miscalculates, the reason is almost always a usability problem." The operating structures were simply not adapted to the situation, he says. This is why Höfler considers it crucial for usability specialists to be involved from the very beginning in system analysis when new products are developed. "We should first think about the operation of a system, and then, as a second step, analyze its engineering process—not vice-versa," Höfler says.

Usability experts at Siemens Power Distribution therefore rely on analyses of work procedures as well as on-site evaluations and user tests; these are studied in the lab of the Georg-Simon-Ohm College in Nuremberg, for example. The lab investigates reciprocal connections between man and machine, sometimes using sophisticated techniques like eye-tracking. In this process, a camera films the face of the user at a simulated operator console in a control room. Software using image recognition calculates which monitor messages the operator is looking at when he or she deals with certain tasks. "One thing we can see from this is whether we’re giving the user maximum support with his work," says Höfler.

Triggered by Vision. "In the future, it will be possible to control and guide some devices without even touching them," predicts Dr. Heinz Martin Scheurer, head of the Usability department at CT. Some Axiom Artis functions can already be activated by voice commands. At Siemens, researchers are also contemplating new interactions that turn eye-tracking into an input system. By looking at a certain portion of monitor, for instance, a user could trigger a specific action. "This is something we’ve already studied," says Scheurer, "but we’re still struggling with a few problems. For example, a situation where the system falsely interprets a more or less coincidental glance."

This problem could be alleviated by a brain-computer interface, whereby an electrode cap worn by the user reads thoughts in the form of electrical activity in the brain. CT experts are already investigating what it would take to link these systems appropriately with conventional interfaces. The principle that applies to today’s mouse, keyboard and voice command applies equally to the eye-tracking control, brain-computer interface, gesture input, and haptic feedback of tomorrow. "The crucial thing is having a mixture that’s well adapted to a given user situation," says Scheurer.
                                                                                                                     Rolf Sterbak