Automation Infrastructure System for a Robotic 30-Ton Bridge Crane.
Automation Infrastructure System for a Robotic 30-Ton
Stone, W. C.; Pfeffer, L. E.
Robotics 98 Conference Proceedings. American Society of
Civil Engineers. April 26-30, 1998, Albuquerque, NM,
195-201 pp, 1998.
robotics; bridges (structures); construction; bridge
cranes; construction automation; construction
simulators; data telemetry; wireless jobsite
This paper describes the sensing portion of a system
used to convert an existing 30-ton high bay bridge crane
to computer control for automated placement of
construction components. The system is being designed
to permit either telepresent or fully autonomous
assembly of representative parts of buildings and
industrial plants, e.g., girders, tanks, and pipes. In
order to achieve six degree-of-freedom manipulation of
the components the traditional crane cable and hook have
been replaced by TETRA, an inverted cable-operated
Stewart platform equipped with various manipulators.
The sensing systems are primarily displacement, force,
and other state sensors. What makes this application
unique is the scale of the robot: the crane's workspace
is 40 m long, 23 m wide, and 24 m high - a volume of
more than 10,000 cubic meters. This scale, and the need
to operate without wires has led to a control system
based on wireless packet communication by intelligent
modules known as "smart pods." The pods interface to
one or several force, displacement, or state sensors.
The pods broadcast their data via wireless ethernet to
base stations which then communicate with the world via
a higher speed networks. The present paper discusses
issues relating to the architecture of the sensor array
needed to operate this large construction robot and the
communications infrastructure needed to supply that
information to remote sites in real time.