My company builds and works with industrial automation, custom CNC machines, and industrial robots. I've observed a shift from purely button-and-neon operated p

My company builds and works with industrial automation, custom CNC machines, and industrial robots. I've observed a shift from purely button-and-neon operated panels from early PLC or relay logic machines, to multifunction keys on the human-machine interface display (HMI) before touchscreens, to a fitful few years when people thought it was a good idea to build machines with VB6 and various serial to digital IO adapters, to purely touchscreen-driven machines with one legally-mandated physical emergency stop button (about when I arrived in the industry, the other machines were mostly historic beasts I've occasionally been charged with maintaining), and back towards multifunction keys. There are usually a few dedicated buttons and indicators for common operations (reset, cycle start, control power on, feed hold, feed rate override, etc), that still makes sense most of the time. I really think multifunction keys are the best of both worlds. As the author of this piece describes, the multifunction display with 20 keys around the outside (or, for CNCs, 10 keys across the bottom of the monitor and 10 off to the right, in a 1-4-4-1 spacing so you can feel exactly which button you're hovering over while you're staring unblinking at a cutter chewing through 5-figure assemblies) is a good compromise. It takes some serious concentrated planning to design a set of keys that are intuitive (top to scroll up, bottom to scroll down, one dedicated for enter, two for context-specific operations, etc), but it gives you the freedom to design relatively shallow but featureful menu systems that you can memorize and get tactile feedback to operate with confidence.