I trust a computer much more than a human to keep a tiny gap at high speed for hours on end.
Also if you have a nice clear barrier, it becomes easier to automatically manage steering.
Also if you have a nice clear barrier, it becomes easier to automatically manage steering.
We saw how human factors can complicate the correctness of code in the Toyota unintended acceleration case. The instruction fed to the system by its programmers were incorrect and not up to industry standards. Computers caused the accidents in that case, despite human intervention by drivers.
And I said I trust a computer more, not that the presence of a computer is automatically enough.
I'm not getting in a manually-controlled plane that's flying centimeters from a hard surface. I will get in some computer-controlled planes doing the same.
(At the very least I want a real-time OS and dedicated range sensors. And the confidence of a plane owner who would lose millions of dollars if anything went wrong.)
What you really mean is you want to see safety data and a track record.
As for the actual planes and auto-pilots, the real point is the kinds of engagements and disengagements that work in the air don't necessarily work on the ground and being so close to potential collisions is part of that.
The implication of the hard barrier is that it's not safe to crash into it. If there are big wheels on enormous shock absorbers making it safe to hit the barrier, then a lot less precision is needed, and you can put almost anything in control, even a heavy clamp that keeps the controls skewed slightly toward the barrier. But that's not the scenario anyone else is talking about.