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Electrical engineering
Course: Electrical engineering > Unit 7
Lesson 5: Bit-zee Bot- Bit-zeeeeeeeeeee
- Bit-zeeeeeeeeeee (long version)
- Parts for Bit-zee and It-zee
- Tools for Bit-zee and It-zee
- Introduction
- Planning and propulsion
- Parts
- Chassis/frame
- Wheel mounts and fenders
- Component mounting holes
- Batteries/power
- Battery wires
- Power wires and on/off switch
- Motors/propulsion
- Motor controller functions
- Motor controller
- Motor controller connections
- Arduino connections
- Digital camera connections
- Digital camera connections II
- 5 volt power distribution board
- Digital recorder/player connections
- Power connector for the Arduino
- Prototype board
- Motor controller connection to Arduino
- Camera connection to the Arduino
- Bumper switches
- LED eyes
- IR sensor
- Chassis modifications
- Camera wiring update
- Programming
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Chassis/frame
In this video we show you how to craft the chassis for the Bit-zee using a $3 piece of Lexan and tap light housing. Created by Karl Wendt.
Want to join the conversation?
- When you were making this video, were you designing and building the robot for the first time or had you built something similar in the past upon which you're basing the design?(6 votes)
- I think they built it in the past other wise they must of done a lot of guessing(1 vote)
- Where can you buy the tap light?(3 votes)
- at any hardware store, Home Depot, Lowes etc, hope this helps(4 votes)
- How does he do all these projects?(3 votes)
- He probably has a college education in several subjects, and most likely also has some help from friends and learns about other subjects to be able to make the courses on this site. But, there are also most likely staff that help keep the site and courses updated.(1 vote)
- why do they need at least 12 volts of battery(1 vote)
- so the propellers can move faster. If they were only propelled by 1.5 volts, it would go really slow(1 vote)
- How do 4 batteries in this configuration of any size between AAA and D(not including 9 volt):
x x
x x
have a total voltage of 12 volts when 4 * 1.5 V(voltage of the battery) = 6 V?(1 vote)- https://www.khanacademy.org/science/discoveries-projects/robots/Bit-zee/v/bit-zee-s-batteries
In the battery video you can see that he uses 8 of them.(1 vote)
- How do you make it if you don't have any of that stuff?(1 vote)
- You have to buy supplies if you don't have any. Radio Shack, Fry's Electronics, and hobby stores are good places to buy these. Not including tools, this project can cost around one hundred US dollars. Prices also depend on how many supplies you already own.(1 vote)
- cant we use a ready made chassis instead of the tap light one?(1 vote)
- Hi Aryan,
Use whatever you can find. A piece of wood, foam board, metal, or even cardboard would work. To get started hot glue can hold everything together. Later when you get more experience you can get fancy.
The most important part is to make something!
Regards,
APD(1 vote)
- Atwhich way and how did he clamp the dremal in place? 4:08(1 vote)
- so he could cut without the LEXAN moving(1 vote)
- does the bit-zee bot have a lid? Or does it's wires and bits show?(1 vote)
- There is no lid, but you can easily make your own. But personally, I like the way it looks better without a lid. I like looking at all the wires, boards, and circuitry.(1 vote)
- can you use a band saw(1 vote)
- Yes, and it would likely be easier and more precise, but most people don't have access to one.(1 vote)
Video transcript
--different components
here for our Bit-zee Bot. And we're going to take
our tap light apart and see if we can use the structure,
the outer ring of the tap light as a way of
supporting or creating a structure for our Bit-zee Bot. So we're taking
all the screws out, and we're going to take
the tap light apart. And you can see the base of it
has a lot of features on it. Screw features, and
battery holder features, and so we're going to see if we
can use the material-- I'm just lining up the motor see if
it fits there with the ring-- and then we're going to see if
we can use the material that's flat, like this sheet
of lexan to support the internal components. The original piece there has
all these raised components so they're not quite
in the right space. So we're going to use the
original piece as a template. And we're going to just trace
it with a permanent marker. And the lexan has a
covering on the outside, so it's no problem
to trace on that. And we're using lexan because
it's a very durable plastic. It machines easily, you
can drill holes through it, and it also looks good. It's clear and very strong. And so this is
called a rotozip bit. It's a bit that allows you
cut sideways in a material. And the Dremel comes with this
fitting that you can put on. You have to take the
collar on the top off. And then once you've
removed that collar, you can put this fitting
on, and this fitting will allow you to basically
use the Dremel like a router. And you can use it to
cut material apart. And so we're going to
adjust the depth of that so that only about a quarter
of an inch of the bit is sticking through. OK, so now that we have our
housing connected to the Dremel and it's all tightly
fastened, and we have it adjusted
to the right depth, we're going to clamp our lexan
to the edge of the table. And once we get the
lexan clamped-- and we're going to only allow about
an inch of the lexan to overhang the table, so
that when we make the cut, the lexan doesn't flex too much. If much more than an inch
hangs out, it'll flex a lot. It's important to only do this
if you have a lot of experience using a rotozip-type tool and
you know what you're doing, because it can be
dangerous if you don't. So we're just trimming
the edge there, and then we're going to go
ahead and trim the other edge. Then what we're going to
do is rotate the plastic and we'll continue the process. It's much easier
to do this if you have a jigsaw or a scroll
saw, because you can just make the cut
continuously, and it doesn't require near
as much finishing. But we only happened to have
a Dremel with us at the time, and so that's what
we decided to use. And in the event that
that's all you have as well, then this will be a
way for you to do it. So we're using our ruler to
measure 90 degrees-- to measure across to find the
center, and then we're turning the circle 90
degrees to make sure that the center's
in the right place. And once we've found
the center, we'll be able to drill a hole
in the center of the lexan and that will allow us to
rotate around a specific point. And we'll be able to grind
the edge of the lexan down to an exact circle. So we're drilling a hole in the
center for our machine screw to fit in. And you can use a nail
if you happen to have one and you don't have
a machine screw. A nail will probably
actually work a little bit better because you could just
nail it through the lexan into the board below. But we happen to
have a machine screw so we're going to use that. We're just trimming the
edges off of the plastic that was sticking up. And now we're going to
clamp down our board. And this is just a scrap piece
of wood that we happen to have. And we've measured the
distance to the center in from the edge of the board. And we're going to drill
our machine screw-- or make sure our
machine screw fits. And then we're going to
put our plastic over it and put the machine screw in. Again, if you have
a nail, you can just drive a nail through the
lexan, and then pull it out after you're done. So we've got a grinding
bit on our Dremel, we've clamped it in
place, and it is just a little bit above
the edge of the lexan. And we're turning it
and rotating our lexan as we go around and
around to remove the burrs and the edges to
make the lexan truly round. So we're fast forwarding through
this because it takes a while. The whole process
took about, I think, about five or six
minutes because you just want to keep turning it to
take down all the high spots, so you get a nice,
clean, round edge. So now that we've got that
pretty well sanded down we're going to verify
that it's round, and it looks like
it's pretty round. And we'll take our screw
out and put it in place. Yeah, that's going to work well. You can see the
screws go in the edges so it's important that
it's fairly round. OK, the fastening screws. OK so now we're
going to use our file and just clean up the edge. There's some burrs and things. We're just going to again
push the file away from us and just take the rough
edge off of the plastic. Right, now that we've
cleaned off the edges, we're going to mark the
points, or the holes, that we need for the
screws that are going to go into our
polystyrene housing through our lexan to hold
that lexan base in place. And so we're just going to mark
those with the Sharpie there, and since the
material is clear we can see right where
the holes need to go. So we're going to clamp that
material in place, the lexan, and we're going
to use a 3/32 bit and drill our
holes in the lexan. And we don't need
to use a drill press or worry too much about
the holes being perfectly centered or perfectly
straight up and down, because the material
is very thin, so if the holes are
not perfect, it's OK. Now it is important
that we try and get them as close to the center of
those screw bosses as possible. Otherwise we won't
get as good a fit. So we're going to use
our break-off blade knife to trim the-- there's a
little bit of excess plastic around the hole
from the drilling, and we want to trim that excess
plastic off so that we can get a nice tight fit
with our screws. So we're just going to run the
knife around the edge there, and we'll do that on both
sides for all four holes. And we're just fast
forwarding there so you can see it in action. Now we're going to take our
screws and put them in place. And this part is
really critical. The polystyrene
housing is very soft and so you want
to turn the screws very slowly when
you put them in. Otherwise you'll
strip the threads out and the screws won't
hold very well. All right, so now the
housing is complete and we're ready to
begin creating our wheel mounts, or our motor mounts.