FIGURE 8. Second Garco patent application 2A.
the aesthetical views of how Chapman intended Garco to
appear when completed. (This part of the patent was
granted early in 1954.) Note he did not show the base that
Garco was mounted on and the arm assemblies are covered
with fabric or rubber.
The second set of patent drawings show more of the
mechanical and electrical aspects of the robot. Figure 8
shows a test column on which the complex ‘Remote
Control Manipulating Apparatus’ is mounted. This part of
the patent was granted almost five years later. Cables 170
and 171 at the bottom are connected to the sending unit
(shown in Figure 9) that replicates the operator’s arm
movement. Pushbuttons and toggle switches enable or
disable sections of the robot’s arms. In Figure 10, a linear
actuator (numbers 96 to 101) moves the arm up or down.
Motor/actuator 106 moves the elbow joint and motors,
while 122 and 126 rotate the wrists and open and close
the claw. It appears that Chapman used dual wound field
DC motors to drive the linear actuators both directions
through gearboxes, as Figure 10 seems to indicate. Figure
From Garco To The New Bots In Town
11 shows an excellent view of the claw and actuators, as
well as the shoulder actuator.
FIGURE 9. Second Garco patent application 2B.
How Is Garco Controlled?
According to an article — Plug-In Workman Built in 90
Days — written about Garco in the December 1953 issue
of Popular Science: “Chapman brings Garco to apparent life
by first opening the circuits and sending electricity surging
into the complex metal body. He then lays his right arm
along a five-jointed electro-mechanical control arm which
has a handgrip at the end of it. The joints can be moved up
and down, in and out. As Chapman twists and turns his
own arm — and the control arm along with it — Garco’s
right arm moves in exactly the same way. Garco is so
sensitive, in fact, that if Chapman’s hand shakes, Garco’s
does too. Garco’s brain was electronic using six aircraft
servo systems. His nervous system consisted of 1,200 feet
of wire cable. A two-way radio transmitter enabled Garco
to make pertinent remarks.
Today’s definition of electronic refers to ICs, transistors,
or at least tubes, but it appears that anything full of wires
and motors was mysterious enough to be called ‘electronic’
SERVO 10.2010 77