You've probably seen reports on and video on the first test flight of the Terrafugia flying car, formally called the “Transition” Roadable Aircraft. It's the latest embodiment of the long-heralded dream and goal of a practical vehicle which be both a car and an airplane.
No doubt, this is an impressive engineering achievement, relying on innovative design, simulation, materials, and fabrication techniques, to cite just a few items. There are so many technical demands and constraints in such a design, and every design decision is linked to every other one.
At the same time, any flying car is an attempt to reconcile conflicting design objectives. This is the challenge faced by designers of almost any product which is supposed to be flexible in its functions.
Certainly, software-based products can transform themselves into many things and take on many attributes, but that is both good and bad. Often, what you end up with is a design which is OK, but not great at any one thing. It can do all the things it was supposed to do, in principle, but it's not really good at any of them in terms of size, weight, functions, or user interface. Even when the user screen is fully configurable and programmable, as with the Apple Phone, there are still areas where the device's design must reflect compromises.
In contrast, a unit which is designed to do just one thing, and do it well, can often provide superior performance, user experience, and at lower cost than the admittedly more versatile unit. The obvious example is today's cell phone, loaded with music player, camera, GPS, data link, and, oh yes, a voice-phone function. They're great, but also a compromise in almost every function compared to a single-purpose design.
Which one makes sense depends on the market you are designing for, the priorities you have, and many other factors. There is no single or easy answer, but we know one thing: nearly every user will have a different view of what they wanted and say “why did they [the engineers] do it that way? It's not what I wanted.”
And the next challenge will be to make the Terrafugia vehicle amphibious! ♦