Are You a Dial-Twiddler?

Test engineers historically bent over bench instruments or larger pieces of equipment twiddling dials, flipping switches, and otherwise manually manipulating measurement functions. ← This sentence is desperately in need of a verb.

But to address the issue, touch screens are great for some uses like iPhones and information kiosks. I'm not sure that they'd be a good idea for use on the display of a test instrument, where the users have a tendency to touch the screen while discussing with their co-workers the data and graphs that are displayed there.

"bent" is the verb

Been done for decades now. Hewlett-Packard has had touch screen logic analyzers for a long time. I think they started with the 16500 series.

I just installed a new piece of equipment that came with a touch screen. One of the adjustments required, previously done with a manually controlled dial, required "sliding" an indicator along a bar graph.

THIS IS A BAD, BAD IDEA. Fortunately, this particular adjustment was not safety critical, so the fact that it took minutes instead of seconds to get the indicator to settle to the correct position was mostly an aggravation. I can see where this would be a MAJOR problem for a life support system, or a critical system control...

Give me old-fashioned knobs to twist...

A million years of evolution with the opposing thumb - perfectly suited for a knob - and some marketing idiot decides to replace it with something totally alien with the way the human hand works.

I see this problem with a lot of consumer products. Form trumps function.

I'll have to side with cwarner on this one. For controlling my phone a touch screen often works great most of the time (how many time have you had to hit the "home" key to go back or backspaced due to a typo?)

The power plant I used to work for had a pretty good control system. During the installation, it was asked if we wanted our turbines integrated into the system, and unanimously we voted it down. We opted for monitoring capability only. For control of multi-million dollar pieces of equipment, we didn't want even the possibility of an "ooops". For things that can easily be undone the touch screen is great, but as cw said, for control of critical things, give me a knob.

Been using them for years now. Make sure they are large enough for a NFL offensive linemans fingers, and keep spares in binstock. They're great if you like recalibrating them often before replacing them. Touching them firmly with a hammer before trashing them can be therapeutic.

"Digital" = knob with notches like a chess rook, and a springy finger doodad as a detent.

They may say that it's all a matter of habit. But I think that in many situations, working with knobs, etc, has distinct advantages. There is a phenomenon in life which could be called the "mass versus significance ratio." In any situation, you have the mass of the situation which arrives via sense channels, and the significance of the situation which is totally in the form of symbols and thought patterns. If the two become unbalanced, the activity can break down. Like an engineer trying to visualize a new design without using sketches. Using the sense channels to control an instrument helps keep things in balance. Beyond that, having knobs on an instrument panel, or real control rings on a camera lens means that that all the instrument settings can be seen by just looking at the instrument. You don't have to navigate menus to make settings which then become invisible when you navigate to a different menu option.

I know that computer-controlled instrumentation beckons designers to use software-driven control panels as well. But I would take the lead from the world of electronic music: Give the musician an instrument that he can play with his body. After all, that's a part of the experience. Though bench testing may be less glamorous than musical performance, I think a certain amount of physical interaction with the instruments is a necessary part of both experiences.

I would judge that the inclination to do away with real controls is mostly a financial consideration. If followed, I think it will make most instruments less usable.