Many aspects of the test and measurement business are different from the way they were relatively few years ago. Perhaps the most obvious example is the people who are using test and measurement instrumentation. A recent industry study shows that 20 percent of electrical engineers now in the global workforce started their careers within the last decade.

Figure 1. Early instruments with analog interfaces required multiple front panel dials to configure measurements, and results had to be transcribed manually.

There have also been other significant changes in the industry; for example, manufacturing companies once typically had large staffs of dedicated test engineers. Today, these companies are often outsourcing test system development and have drastically cut the size of their test engineering departments. Shrinking in-house staffs and shortened test design schedules mean that engineers have far less time available to focus on becoming instrumentation experts.

A Look Back

Test instrument design is undergoing some striking changes as instrument user expectations have evolved along with the users themselves. For perspective on how instruments and user interaction have changed, it may be useful to look back at how instrument interface designs have evolved over the last six decades.

In the 1950s, interacting with instruments was often a laborious process. Configuring a measurement typically required twisting dials to select the desired functions and set ranges. “Taking data” often involved transcribing readings from an analog dial manually or measuring traces from a printout from a strip chart recorder with a ruler.

When digital instrumentation began to replace analog designs, the new user interface designs began to employ LED and LCD digital readouts (Figure 2). Function and range setting knobs were increasingly replaced with pushbutton controls. Engineers no longer needed a clipboard or notebook to record data when early communications interfaces like RS-232 and GPIB were added to instruments to support system integration and triggering, remote programming, and control, as well as transfer of data to an external PC for analysis and display.

Figure 2. Starting in the 1960s and continuing through the 1980s, LED and LCD digital displays and pushbutton controls increasingly replaced analog dials and knobs.

By the 1990s, users had begun to demand increasingly detailed information on their measurements, which eventually led instrument makers to develop brighter, easier-to-read vacuum fluorescent displays that could display multiple measurements simultaneously from a single measurement connection. To allow users to configure the display settings and performance options, vendors often assigned multiple functions and performance options to the same front panel button (Figure 3).

A Look Forward

Figure 3. Vacuum fluorescent displays and multi-function buttons became increasingly common in the next stage of user interface evolution.

Over the past decade, instrument vendors have been striving to develop user interfaces that offer their customers more information faster. Due to shrinking design cycles, many engineers are under greater time-to-market pressure than ever before, so they need to acquire reliable data on experimental devices and circuits as quickly as possible. Although digital multimeters (DMMs), for example, have long been fixtures on every electrical engineer’s benchtop, they haven’t always provided the type or depth of information users need to do their jobs. To get the answers they need, DMM users have had to turn to other kinds of instruments to go “beyond the numbers.”

Figure 4. The latest benchtop instruments combine intuitive touchscreen operation with functions rarely found in a single instrument. For example, Keithley’s Model DMM7510 graphical sampling multimeter integrates a high-speed digitizer that supports displaying and analyzing voltage and current waveforms and transients precisely.

At the same time, changes in user characteristics and expectations about ease of use have led instrument manufacturers to create user interfaces that incorporate many of the same control and display innovations that have revolutionized consumer products like tablets, smartphones, and cameras. The most prominent of these innovations is the use of advanced capacitive touchscreens with multi-point, pan-pinch-zoom-swipe operation, which simplifies interacting with data. By providing immediate visual feedback and a more content-rich display, touchscreens support faster learning than other control and display approaches, and give users greater confidence in what they’re doing. This can substantially reduce user learning curves and training requirements while improving measurement integrity and testing efficiency.

Figure 5. DMMs that combine built-in graphing utilities and a large screen make it easier to display and compare stored test results because users are no longer dependent on an external PC to analyze measurements.

The intuitive nature of touchscreen interfaces allows users at all levels of testing sophistication to become experts quickly. They also offer the advantage of providing instant access to context-sensitive help, eliminating the need to consult a user manual to get an instrument up and running. For those relatively new to testing, these instruments can speed up the measurement process by helping users test accurately and get results quickly, and allows them to focus on their next breakthrough rather than on learning how to configure the instrument. With simplified setups configured from the front panel (Figure 4), such instruments support faster time-to-measurement and significant improvements in test productivity.

Simplifying the User Experience

Instruments with touchscreen interfaces aren’t just for novice or infrequent users. Touchscreens allow display of results using larger, more legible characters; provide more details about the measurement; and support on-screen data display and analysis capabilities never available before (Figures 5 and 6). The flexibility to present data graphically as well as numerically helps users explore results in a way that goes beyond the numbers. Because touchscreen displays are software defined, they are easily changed to reflect the different controls and indicators required for different applications, freeing up valuable “real estate” on the instrument’s front panel.

Conclusion

Figure 6. Instruments with full graphical plotting windows make it easy to convert raw data into useful information easily and display it immediately. The touchscreen supports “pinch and zoom” operation to allow examining data on the graph in detail.

As time-to-market pressures increase, more and more users will demand that their instrumentation deliver more in-depth answers quickly and without compromising measurement integrity. Fortunately, instrument vendors are coming to understand that helping their customers do their jobs with greater confidence is a prerequisite to creating successful products.

This article was written by Jerry Janesch, senior market development manager, at Keithley Instruments, Cleveland, OH. To learn more about how new interface designs are redefining how users of all levels of experience interact with their instruments, visit www.touchtestinvent.com .