Decontamination and decommissioning (D&D) workers can now trade their cumbersome steel-toe boots, hard hats, and protective garments for an ergonomic command chair and computer screens.
The Modified Brokk Demolition Machine with Remote Console (Tech ID 2938) is a powerful, custom-equipped robot designed to ensure worker safety at the worst D&D jobs. It was created by combining a Swedish-built Brokk 250 robot (Tech ID 2100) with a newly designed remote console. The machine looks and performs like something out of a futuristic action movie, wielding a powerful 15-foot hydraulic boom (arm) for breaking hard materials, loading, and digging. With the hammer attachment, the Brokk 250 delivers 600 foot-pounds of impact with up to 1500 strokes per minute. Now, all of this power can be directed from a completely remote location. An operator can sit comfortably indoors and guide the machine with the help of four video screens and a two-handle joystick, safe from high-radiation areas and falling debris.
The Modified Brokk is designed to go into an environment where people cant be, said Matthew Anderson, principal engineer at Idaho National Engineering and Environmental Laboratory. In a single INEEL deployment, the Modified Brokk lowered risk to workers, saved more than $66,000 in D&D expenses, and shortened the cleanup time to one-tenth the original schedule. Moreover, Anderson noticed, D&D operators were quick to accept the new tool. They were skeptical at first. Theyre used to grabbing jack hammers, he said. They were pleasantly surprised.
Three DOE initiatives contributed to the Modified Brokks development.
A standard Brokk demolition robot was first demonstrated in 1997 during
the Deactivation and Decommissioning
Focus Areas large-scale demonstration and deployment project
(LSDDP) at Argonne National Laboratorys
Chicago Pile 5 (CP-5) Research Reactor (see Initiatives,
Summer 1998). Based on the machines performance, a Brokk
250 was then deployed at INEEL through OSTs Accelerated Site
Technology Deployment (see Initiatives,
Winter 1998). Most recently, the retrofit remote console was built
from a Compact Remote Control (CRC) system (Tech ID 2180), developed
at Oak Ridge National Laboratory
through OSTs Robotics
Crosscutting Program with additional engineering from INEEL staff.
The result is that a single operator can direct the robot from as
much as a mile and a half away.
The INEEL demonstration was intended to show that computer video technology enabled operations from a remote site as efficiently as closer, line-of-sight operations. Standard Brokk controls enable operation at a distance of 400 feet from the work area, safe from most types of demolition hazards but not completely protected. The Modified Brokk was tested during January 2000 in the basement of the former Security Training Facility. The task was to remove, size-reduce, and stage overhead piping and facility equipment. Operators familiar with the standard Brokk 250 became proficient with the controls and new monitoring equipment after just one day of training. Anderson said that they were so pleased that they asked to keep the Modified Brokk for two more days to finish the job. Thus, the demonstration became a deployment. The entire deployment was coordinated from an enclosed trailer, far removed from the work area. A fiber-optic tether sent video images from the site to the control trailer.
Innovative technologies play an important role in D&D of DOE
facilities. Such structures often have radioactive and hazardous contamination
and were built from a variety of heavy materials. Concrete block;
structural steel; and massive, cast-in-place, steel-reinforced concrete
are difficult to dismantle with traditional means. Often large amounts
of steel piping and equipment are also present. Testing has shown
the Modified Brokk to be up to the job.
According to the manufacturer, Holmed Systems AB, the standard Brokk
250 can be used to dismantle bridges, beams, floors, copper plants,
and nuclear facilities. Brokk robots, which cost approximately $130,000
for basic equipment, are also suitable for interior demolition, slag
removal, and furnace demolition. At the CP-5 LSDDP, it was even used
to segregate and containerize waste without operators entering the
INEEL engineers found that the lightweight Brokks extensive
arm reach delivered tremendous hammer blow force for its size. The
arm is mounted on a revolving table atop a small, tractorlike base.
The arm itself is made of three extendable parts, designed to accept
attachments such as a hammer, rotating grapple, loader bucket, and
rammer shear/crusher. Attachments can be changed in approximately
10 minutes. Anderson said the unmodified Brokk 250 has already become
a baseline D&D tool, often replacing traditional methodologies,
such as manual saws, backhoes, and explosives. The new remote console
makes the robot even more versatile.
The remote console modifications cost $120,000. However, nearly half
of that was for the specially equipped chair, which can be shared
with multiple Brokk robots. The ORNL-developed CRC portion of the
remote console includes the operator's chair and its base, designed
for easy transport and setup. It serves as the data link
for the electronic hardware that controls the video cameras and viewing
monitors. INEEL staff added the fiber optics; robot-mounted, image-stabilizing
cameras; video software; and detached, stationary zoom cameras to
provide a broader view of the work site.
The Modified Brokk is already getting attention from others with
D&D needs. According to Anderson, the Department of Defense has
expressed interest in the system for an old naval reactor facility
undergoing D&D at INEEL. They came to us and said, We
want to duplicate what you have, Anderson recalled. He
also expects a wide variety of other deployments on upcoming D&D
projects at INEEL.
One reason the Modified Brokk is gaining popularity is its durability.
It can be operated on double 10-hour shifts for weeks without failure.
The expected useful life is about 10 years.
Anderson and others are researching ways to further improve this
D&D tool by eliminating the tether and developing a wireless,
completely remote operating system. Currently, an additional worker
is required to be at a work site to occasionally move the tether.
The limitation right now is primarily the interference and dropout
associated with commercially available wireless video systems we have
evaluated thus far, Anderson said.
Even with the limitations of a tether, the Modified Brokk promises
to change the approach to D&D jobs in and out of DOE. Numerous
applications outside of D&D are also likely. Manufacturers of
the standard Brokk robot even claim that it is capable of breaking
open bank vaults. For now, engineers like Anderson are happy knowing
that they can protect workers from hazards like radiation, a benefit
difficult to measure in dollars.
More information on the Brokk Demolition Robot is available from
a page of the INEEL EM Technology Catalog at http://techcatalog.inel.gov/searchreportresults.asp?id=6.
You can also contact Matthew Anderson, INEEL, (208) 526-4308, firstname.lastname@example.org.