Since the floor has variations in height, the HoverBot's skirt
must be flexible to maintain its cushion of air. If the skirt
wasn't flexible, the air cushion would blow out one side of
the HoverBot causing it to crash to the ground. A plastic bag
attached to the bottom deck and filled with air from the lift
fan is perfect for doing the job.
1-3/4 inch diameter circle. Now, cut out the octagons and
their center circles with an Exacto knife or scissors. Next,
drill two holes — one centered on each side — in the nozzle
plates with a 1/16 inch drill bit. I recommend stacking the
nozzles when drilling the holes so they align properly.
Two bolts and spacers hold the nozzle plates the
proper distance from the bottom deck. I found a good
spacer to be two #4-40 bolts 3/4 inches long, two #4-40
nylocks (nylon lock nuts), and two 1/4 inch diameter
styrene plastic tubes cut 3/8 inches long.
To ensure proper alignment of the nozzle, center one
of the nozzle plates over the lift fan opening in the bottom
deck and mark the location of the two spacers. Then, drill
two 1/8 inch holes in the bottom deck for the spacers.
The HoverBot requires two of these nozzle plates.
After gluing the fan clamp on the bottom deck, use a
sharp Exacto knife and cut out two notches 1/2 inch wide.
The nylocks from the nozzle will attach here. Notice that
the hole in the deck where the fan draws air is slightly
smaller than the diameter of the hole in the fan clamp.
Now, test the nozzle by stacking the two nozzle plates,
running the #4-40 bolts through them, stacking the plastic
tubes over the bolts, and then attaching the nozzle plates
to the bottom of the bottom deck. The nozzle will look like
the image below this.
Next month, we’ll start on the skirt and electronics.
NearSys is about to produce a HoverBot kit, however, my
articles will contain enough information that a SERVO
reader can build one from scratch. (Just don’t start selling
NearSys HoverBots!) Check out the NearSys You Tube
channel to watch a short video on the HoverBot. I think
you’ll be impressed enough with its performance that you’ll
want to make one for yourself. Be prepared for a new
paradigm in robot control. SV
The nozzle plates are held 3/8 inches below the bottom
deck. In this image, the bottom deck is upside down.
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