SCARA

(described in various works, particularly
Frederik Schodt's Inside the Robot Kingdom)


What you are about
to see is the arm that holds
perhaps the greatest
promise of all. One moment—
I'll turn the light on for you.

This is our baby—
the Selective Compliance
Assembly Robot
Arm—quite a mouthful, I know.
We call it SCARA for short.

Unlike most other
working arms, SCARA is not
anthropomorphic.
Its action was inspired by
a Japanese folding screen.

Was that a question?
Yes. By "compliance" we mean
the capacity
to adjust its position
according to changing needs.

Like a human arm,
it can exploit the local
geometry of
pegs and holes, letting the parts
fall into place by themselves.

Simplification
is key here. It has just four
degrees of freedom,
but works more accurately
and faster than you or me.

Note the simple end
effector. With no fingers,
it can grip even
fragile payloads gently for
drilling, pressing and punching.

No supervision.
That's correct. And almost no
down-time. You don't need
me to tell you what that means.
Yes. Twenty-four hours a day.

This room is threading
nuts, but that's not all it does.
It's cornered the light
assembly market, in spite
of a few limitations.

Flexibility
along the vertical plane
is quite low; that's why
it inserts screws, bolts and dies
horizontally, like so.

First it has to find
what we call the notional
center of the hole,
then use manipulable
force to ease the object in.

As we pass between
the lines, I would just ask you
to stay well within
the marked paths and not to touch
the arms while they are working.
















"SCARA"
copyright (c) 1997 by
Melissa Monroe.
All rights reserved.