A new area of ergonomic material handling has
opened up in the last few years and our company is proud to be one of the
leading installers in this field. Intelligent Assist Devices are
basically hoists, balancers and trolleys with embedded computer
controls. The
electric winch
is becoming the tool of the past. This intelligence gives these devices the ability to do
many things that were never before possible, like sensing weight via a
load cell and adjusting height in accordance, or following a
preprogrammed path from point A to point B. IAD's are available as
both pneumatic and electrically powered devices, below please find a
brief description of both types:
Pneumatic IAD
Pneumatically
powered IAD's offer the combination of proven mechanical balancing
technology and the intelligence of electronic controls all in one
package. These devices offer many of the some of the same
features as the all electric models below, but at significant cost
savings. Probably the single most powerful feature that most
IAD's offer is the "Float" mode. When in float mode,
the device can detect slight changes in weight of the object being
positioned. The operator can physically lift or push on the
object and adjust its position without his/her hands being on the
controls. So, if the part needs to be shoved into an alcove and
then pushed down into position on some bolts, the operator can
accomplish this without even pushing a button. Some benefits of
the pneumatically powered IAD's are that they can usually lift a
little more weight than the electrically powered IAD's and they are
more economical to purchase. One drawback is that because they
are air operated, they tend to be a little more jerky than the
electric ones, which can cause problems in some applications.
Electric IAD
As
with the pneumatically powered lifting IAD's above, the electrically
powered units have the ability to be pre-programmed with a specific
lifting "profile". The electric units
are capable of high speed lifting or slow and precise placement,
whatever the task demands, unlike their predecessor, the
electric winch. No matter how many different speeds make up the profile
of the lift, these units are smooth to operate, even for large loads
there are no jerky movements.
The unit pictured at the left is powered in the z-axis only,
movements in the x axis are powered by the human operator.
Although shown with a hook, custom end effectors can be attached as
needed for the task at hand.
Cobotics iLift & iTrolley
Although
we deal with many companies products, there is one product that stands
out as a leader in IAD field at present. This is the combination
of the iLift and iTrolley from Cobotics. The iLift is similar to
other electrically powered IAD's as mentioned above, having similar
features and
capabilities,
however, when coupled with the iTrolley, also from Cobotics, you get
a whole new world of possibilities. Using the iTrolley, you
can maneuver the iLift not only in the z axis, but also in the x and
y. You can use a 1, 2 or 3 iTrolley setup for controlling the position of
your part within your system.
A
one axis iTrolley system is easy to envision, you have an iTrolley
suspended from a rail. Then suspended from the iTrolley is the
iLift. You can program a motion sequence into your system and
have it deliver a part from position A to B. Now, what if you
need more than just x and z movement? Add three rails and an
iTrolley on the middle rail, now you can position your part within x,y
and z space. What if the part is heavy and requires more torque
to move? Put up two rails with an iTrolley on each and have a
full bridge and rail system, you have x,y and z movement, and quite a
bit of mobility within the confines of the system.
One
other important factor about the iTrolley, it almost takes
inertia out of the equation. In a traditional bridge and rail
system, as you pull along the part, the trolleys naturally lag
behind. Then, when you stop the weight, the trolleys keep moving
causing a pull on the part. Not, with the iTrolley. It has
a cable deflection sensor built into it. It will detect the
angle of the cable and change the acceleration of the iTrolley as the
situation demands. What about negotiating curves? The
iTrolleys are all electronically linked, so the iTrolley on the inside
of a curve will slow down, and the iTrolley on the outside will speed
up, the net effect is that your part moves in a smooth path the whole
time, always hanging vertically, i.e., very little swing, as the
pre-configured path is traversed.
I want to say that the iLift / iTrolley combination is a little
more expensive than competitors, but there are no
competitors. If you need this kind of functionality, they are in
a class by themselves.