Sometimes, all you need to run a machine is an on-off switch. At other times – if you’re piloting a Tesla Model S, for instance – only a 17-inch touchscreen will do.
The interface between humans and machines is both complex and subtle. There are many ways in which humans can tell machines what they want them to do, and many ways in which a machine can provide feedback.
The human-machine interface has two parts: Switches, thumb wheels, keypads, joysticks and touch screens are examples of the physical part, which we can see and touch. The other part is ergonomics, a broad discipline, that is concerned with adapting machines and tools to humans’ skills, limitations and anatomy. Ergonomics aims for usability, safety and, above all, user productivity.
But while the focus on user productivity is driving user-friendly design, what’s not often recognized is that it can also contribute to a “fuzzier” benefit – user satisfaction, that warm feeling you get when something works really and unexpectedly well.