for mounting mechanisms and sensors.
The newest Runt Rover is the impressive Bogie, which is
the other Runt we acquired for experimenting. The Bogie
has six motors, six wheels, and a super cool rocker-bogie
suspension arrangement. The Bogie towers over its fellow
Runts with nearly five inches of ground clearance, and
features a simple plate for mounting.
Runt Rovers Assemble
Now that we’ve become acquainted with the whole
crew, we can take a deeper dive while we assemble the
Sprout and the Bogie. First up was the Sprout. For starters,
we laid out all of the parts much like is shown on the
website. It’s a surprisingly small number of parts — only 13
individual pieces! Perhaps most surprising is that the Sprout
actually requires no screws whatsoever — everything snaps
Just like with the grippers we worked with last time, the
assembly instructions took the form of online videos. The
familiar voice of the patient narrator takes you through each
step, first identifying the parts you need and then showing
exactly how things go together. The plastic parts all come
with a rough edge and a smooth edge, so it’s easy to know
if you have them in the right orientation. The snap-together
parts strike the perfect balance between being easy to put
together but snug enough to assuage any worries about the
bot coming apart at the seams. It’s the perfect interplay, like
between Johnny Carson and Ed McMahon.
Even the motors snap into the frame. The DC motors
themselves are pretty impressive little packages. The motors
are small and have a nice little gearbox attached to them.
The output shaft from the gearbox is plastic with a flat
edge, which fits nicely into the wheels that come with the
kit. The motors even come pre-wired with nice solid pins on
the end — not some frayed end of stranded wire. When it’s
all said and done, the Sprout weighs in at just over half a
One of the features of the Runt Rovers that are touted
throughout the ServoCity website are the snap-on
microcontroller mounts. The mounts are two U-shaped
brackets with a stepped tooth-like structure on the inside
curve. They looked simple enough, but the site ballyhooed
them as an innovative and hassle free way to mount any of
the popular microcontroller boards.
After testing them out ourselves, we are definitely
believers. We slid an Arduino Uno in nice and easy by
gently spreading the pliable plastic pieces. Once in place,
the board was as solidly fixated as Lippy the Lion on one of
his get rich quick schemes (despite the entreaties of Hardy
Har Har). We could pick up and shake the Sprout, and the
Uno board was at no risk of coming loose.
The unobtrusive mount also ensured easy access to
every port and connector on the board. If we wanted to
switch out the Uno for something bigger like a Raspberry Pi
board, all we had to do was slide it out and affix the bigger
board to the wider set of teeth. No more fiddling with
posts and screws whenever you want to remove or install
Once the Sprout was together, we were ready for the
more sophisticated Bogie. The Bogie requires a few more
parts, and entails screws as well as snap-together parts. At
the beginning of the instructional video, it tells you what
tools you need. For the Bogie, the video recommends a
Phillips head screwdriver and a pair of pliers. The
recommendation for pliers seemed a bit odd to us.
In the instructions, the pliers are used to hold nuts in
place while the screws are tightened. A pair of pliers will
indeed get the job done, but we preferred to go with a
small socket wrench. Since we had the ideal tools at our
disposal, we might as well use them.
We actually think the pliers recommendation speaks to
the admirable goals of the Runt Rovers. The Runts are
SERVO 08.2015 71
Twin brothers hack whatever’s put in front of them, then tell you about it.
THE SEEDS OF THE SPROUT.
THE SPROUT COMES TOGETHER IN A SNAP.