Exoskeletons provide users greater
endurance rather than greater strength
contact with the body, including hip belt
and arm cuffs, are available in different
sizes. They can be removed for washing or
replaced when worn. ‘Hundreds’ of units
of the ExoVest have since been sold.
Bringing the weight down was a
difficult design challenge, one that led to
a complete reevaluation of the device,
Haas states. “We can make a device that
weighs half as much, but then you can’t
provide as much force as the level four
spring provides, because it puts too much
strain on the lighter-weight components.
The ideal weight of a device is zero
pounds. It was a constant battle between
where shaving weight off was worth what
you had to give up, and where it wasn’t.”
The team would try to reduce weight by
redesigning parts with lighter components,
or swapping in lighter materials such as
carbon fibre where possible. “We were
looking for every opportunity to shave out
an ounce here or there. The idea was that
if we add up enough of those, we can take
our vest that started at 18 pounds, move
it down to 14 pounds and find in the end
that we got it under 10 pounds.”
Weight also factored into persuading
potentially dubious workers to use it,
he adds. “A lot of companies who are
coming to us know that these jobs which
have a negative rating ergonomically are
resulting in injuries over time. You still
have to convince the user, who says:
‘Why do I need this; I can do my job every
day without this.’” For workers to receive
the benefits of the device, both now and
into the future, they have to be willing to
strap something to their body that is not
the same as just wearing a T-shirt, Haas
points out.
THE VITAL DESIGN ISSUE
Comfort was also a vital design issue for
Swiss design company Auxivo, developers
of the yet-to-be launched LiftSuit, a
harness for lifting objects such as
suitcases ranging from 5kg-25kg, currently
on trial at the Basel Airport, Switzerland
with ground handling company Swissport.
Volker Bartenbach, CEO of Auxivo,
states: “We have forces up to a couple of
hundred Newtons, depending on the level
of support. So how do you interface these
forces correctly with the human body to
ensure that it’s a good fit, that the force
transmission is working, but it remains
comfortable? This is the balancing act
of all of these exoskeletons. Otherwise,
if you have a pressure point like with a
backpack, you’ll want to take it off. And
that is not acceptable, actually.”
The LiftSuit, said to weigh less than
1kg, consists of a series of straps
running to blocks of an elastic material at
the back. When the user reaches down
below hip level, or leans forwards to hold
something in place, the straps pull on
the elastic, which stretches. That stored
energy then pulls the user back up. Load
in the lifting muscles of the upper and
lower back, hips and hamstrings can
be reduced by 10-30%, Volker claims.
Like the other exoskeletons, this device
compensates for gravity, but of the whole
upper body, rather than just the arms.
Like the others, the suit reduces general
fatigue. To put it on, users slip into the
Applications include construction,
manufacturing and engineering
shoulder straps, and then fasten a hip
belt. Unlike the others, there are also
closures that go around the upper legs.
Applications include not only baggage
handling, but also healthcare – nurses
spend a lot of time bent over patients,
for example – as well as logistics,
construction and perhaps agriculture, too.
A key feature of the design is that it still
provides benefits to users when they are
kneeling, for example in a cargo hold.
“It’s almost impossible to find a technical
solution for inside an aircraft hold,” points
out Swissport innovation and IT manager
Silvio Bosshardt, speaking about robots or
other non-wearable assistance machinery.
Not only are the spaces confined, but
aircraft operate on tight turnaround
times, complicating the deployment of
equipment.
Having developed the basic
functionality and having proved the
concept, Auxivo is now in the process
of selecting materials and making final
designs. “We will rely a lot on textiles
to keep the weight down and make it
breathable,” Bartenbach says.
Austrian design agency Edera Safety
took the testing element of exoskeleton
research and development to an extreme
in developing a sports back protector
under the brand name ‘adamsfour’ that
is expected to launch next year (prototype
pictured, p15). The company plans to
launch the first product as a concept
design at an international sports fair
next year, having won two contracts with
sporting goods brands.
MD Thomas Adams Saier’s inspiration
16 www.ied.org.uk
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