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charges the toothbrush’s battery.
This type of charging is perfect
for small devices since the charger
base uses very little current, as do the
needs for the charging circuit in the
toothbrush. It’s inefficient in this
application but works just fine.
However, with the much bigger
current needs of a large robot with
hefty batteries, efficiency is very
important. Not only will the coil in the
floor need to be continually active,
but the air gap between the two coils
will need to be as small as possible,
which means the robot will be able to
‘go to dinner’ with its coil exactly in
line with the base.
When the robot is roving about
the house, a large conductive metal
object accidentally set on the base
can cause a large current draw. The
Haier robot vacuum cleaner
robot shown in Figure 6 does
use a side-mounted coil system
for charging the robot.
Yes, a sensor can detect the
presence of the robot and turn
on the current as required, but
why use this less efficient
method? All robotic vacuum
cleaners have a charging station
that the unit can detect and then
slide into the live contacts for
charging — a far more efficient
and less expensive method.
How Can Robots be
Made More Useful in
We’ve looked at a few points
about improving a home environment
for robots. Now I’d like to look at
improving the robot itself. As you
might have noticed in recent news
about the ‘latest and greatest’ robots
that are being manufactured, many of
these creations differ very little from
the previous year’s models.
To me, many of these ‘robots’ are
little more than an Amazon Alexa that
sits on a table and wiggles and has a
They are attractive and have
numerous styles of cute eyes that the
designers hope will have their robot
stand out from the competition. Some
have implemented facial and voice
recognition and have a bit of crude AI
to allow them to interpret human’s
needs and wants better.
Touted as robotic appliances, they
are little more than expensive
entertainment devices in my opinion.
For the most part, many are not even
mobile and very few have any sort of
ability to usefully manipulate objects
in the assistance of humans.
What is a Useful
Wow! That’s a loaded question.
What is the best tool? What is the
best car? What is the best seafood
restaurant? What is the best robot?
We all know the answer to that
question: the one we think is best.
The same applies to a machine as
complex as a personal home robot.
As an example, If I were
homebound and had to use a
standard wheelchair that I propelled
with my arms and hands, I would not
necessarily need a robot that had to
assist me into and out of bed or the
bathroom and bring me my food that
it had prepared to my liking.
Perhaps, I can get around my
home just fine and can even drive,
tossing my folded wheelchair into the
back of my car and using my crutches
to get myself into the driver’s seat.
However, someone with more
disabilities would gladly pay many tens
of thousands of dollars to have such a
capable personal robot assistant.
Basically, the Wired article was
centering on a large mobile robot that
was designed for a home
environment, so we don’t need to
consider all the table-top models that
are not mobile. We can also dismiss
the smaller 20 pound or so robots
that can rove about a limited area,
and even the taller but lighter
telepresence robots that can be
remotely-controlled or autonomously
designed to follow us around our
home. I’m thinking of the large
machines in the 100 pound plus class
that have one or more functional
arms to assist humans in their
Designing a Large
The needs for a truly useful
personal robot assistant in a
private home will probably end
up with a mass over 100 pounds
or more. Such a robot could be a
life saver, assisting a person from
a fall to the floor and calling
emergency personnel, or, it could
also be a life-taking device should
it topple upon a frail person or
fall down a stairway and strike
someone. Safety must be at the
top of the list in designing a
large robot to operate within a
person’s private space. Not only the
dangers in the weight of the robot,
but moving joints have the potential
of pinching if not protected from
Functionality of a
I firmly believe that if a person is
in a specific situation — whether that
be a physical condition that is age
related, a specific disability caused by
injury or disease, or just that someone
desires a little physical help around
the house — a truly functional robot
assistant can be designed and
developed with today’s technology.
Grandpa doesn’t need a robot to tell
Figure 6. Haier wireless robot vacuum charging system.