You are probably right. The Optimus Maximus (and Popularis) keyboard(s) featured OLED screens in each key. The function label of each key could them be changed as the application demanded. It does look useful. Not sure how popular the $1000 USD keyboard was. I am sure it wasn't a happy time for buyers when they dumped a Diet Pepsi on the keys... you know it happened.
Also see the Optimus Mini-six, a 6 spot keypad for $700 USD.
Cabe, For starters the interface to a rugged pushbutton is more robust than the interface to a touchscreen would normally be. Next, buttons in a row below a screen, used as smart buttons, which change function depending on their screen label, are often very durable. The one button that I have seen fail had been accidentally filled with oil and metal particles after it was installed, when holes were drilled in the panel abobe it without any precautions being taken. But that same model of button has survived mud and floods and being hosed off to clean it. But those buttons do cost a few dollars each. The seven cent buttons are not so robust and durable.
I really don't see that anything better needs to be designed. For systems that are mission critical, and those where reliability trumps following the current fad, non-touch systems have been much better for quite a few years. One more thing is that the off-screen buttons use less power to operate, and incur less circuit complexity, making them more reliable in a very fundamental way. Of course, that atttitude would not add anything to the profits that are obtained from selling touch screen systems.
Do you think you could design something better than what is currently available in the touch market? If so, perhaps you should work on that. Produce a concept, flow charts, etc. If patented, you may be able to get ahead of the big contenders. Then, sell the design. Just a thought.
An interesting HMI that I created a while back used an alph-numeric display with several buttons below. The function of each button depended on the message displayed. What made the interface unique is that when the system was functioning correctly there were several messages that went by so fast that they were not noticed, but when mechanical parts of the system would hang up or get stuck, there woulkd be a message asking them to wait for that function. A form of diagnosics that did not need any branching logic, it wound up being very reliable.
The buttons below the screen served the similar purpose as tough screen buttons, but they were waterproof and did have a nice click feel when operated. Sot of "haptics for free"
Have you ever made a HMI before? I have made a few in the past, and I was faced with the challenge of making a simple and intuitive system. I have to tell you, it is difficult. What made sense to me, was not clear to others. After the attempts to make a complete system, I switch to the one button approach. "Hit it, and it goes" methodology.
Cabe, that is exactly my point, which is that in many applications the touch function is just sort of stuck in, not well thought out ast all. Those applications would be far better served with actual buttons. The 17 cent touchscreen is not reliable and it does not last long, either. My point is that it would be much better to do the job right, instead of using some new technology that does not work very well.
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