[PaulDavisThe1st]

What machines have we built that reflect a reduced and simplified model of how some part of a human works (other than as a minor and generally invisible research projects) ?

[dragonwriter]

> What machines have we built that reflect a reduced and simplified model of how some part of a human works

A very large number, e.g., lots of implants and prosthetic devices for one fairly large class.

[zmgsabst]

Electronic are a simplified model of the brains used by computers:

They emulate the faculty, rather than biology.

[dekhn]

any chemical or large industrial plant built in the last 30 years

[PaulDavisThe1st]

I think most industrial chemists would likely disagree. But I guess YMMV.