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Electrical engineering
Course: Electrical engineering > Unit 7
Lesson 3: Spout Bot without Solder- The goal of Spout
- Parts list
- Tool list for Spout
- Tools and parts to build a Spout
- Connect the SPDT switches
- Attach the LED eyes
- Wire the SPDT switches
- Create the motor mounts
- Secure and wire the motors
- Install on/off switches
- Connect the LEDs to an on/off switch
- Attach Spout's antennae
- Add Spout's tail
- Give Spout some grippy feet
- Spout in a maze
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Attach the LED eyes
Created by Karl Wendt.
Want to join the conversation?
- At, can the wire be attached to the switches before the switches are glued to the battery holder? 2:24(10 votes)
- I agree you should follow directions it is safer(5 votes)
- how old do you need to be to do this alone?And if you are yong and can't work alone how old would the help need to be.(6 votes)
- if you practice it will be easier,and faster than before(1 vote)
- Could you use hot glue instead of the electrical tape on the red wires / LEDs connection?(5 votes)
- I don't think so. Hot glue doesn't act as a great insulator but is a great connector. Electrical Tape works as both. The hot glue could drop off and they wires could touch another connection to make a short.(4 votes)
- Can you connect a remote to your spout bot?And control it?They should make a section where they connect or build the remote don't you agree?(3 votes)
- I do agree, it would be more beneficial for the purposes of learning, but what if someone is trying to teach this to third graders? It would be hard enough as it is!(1 vote)
- At, why are red LEDs used for eyes? Can you use other things or other LED colors? 8:14(2 votes)
- Probably you can use a small light or other colors.(3 votes)
- Do the resistors need to point in a certain direction? He does not specify if the current needs to flow through the resistors in a particular direction.(2 votes)
- I think I saw elsewhere that it doesn't matter which way the resistors are put in. Don't quote me though! :D(3 votes)
- Are you moving faster along building this bot, or are you just doing it in a different order?(2 votes)
- From where would I get this products in BANGLADESH anyone know?(2 votes)
- Alibaba? Amazon? An online hardware store would work, I guess. Since you would already know what you wanted, you could buy duplicates to make more that one!(1 vote)
- Can the eyes be left off the spout bot?(1 vote)
- What are the pros and cons of stranded vs solid core wire?(1 vote)
- Hello Shawn,
Cost and performance.
For a given size the solid core wire is generally be less expensive as the larger conductors are easier to work - simple machines at factory. The solid wires are easier to terminate. Take your house wiring as an example. An electrician can strip the insulation and install a device such as a power outlet in less than a minute.
As a rule the stranded wire is more flexible and less prone to breakage. This is important for applications where the wire is continually stressed such as a power cord of electric guitar cable.
You may want to research "skin effect" and "litz wire."
Regards,
APD(2 votes)
Video transcript
OK, so in this
video, we're going to connect our LED lights. The LED lights are
going to be used to test various
parts of the circuit, and they're also used as eyes. Now, LEDs are
polarized, which means it does matter which
direction the power flows through the LEDs. LEDs usually have one
short leg and one long leg. The long leg is
usually positive, and so we want to make sure that
we match up our two long legs together. If we connect a short leg
and a long leg together, it will have problems. They won't work the way
they're supposed to do. So we're going to look
for our two long legs. Once we've got those two
long legs figured out, we're going to bend them out
so that we can connect them together. And so we're going
to display those two legs there on
the LEDs, and now that we know that there
are two positives together, we're going to twist them
together-- just twist them around one another. And we want to make sure that
the twists are very tight, so we have a really
good, solid connection. So just keep twisting
those legs until they've been twisted around each other
probably between 5 and 10 times. So then we have the
negative legs of the LEDs on the outside, and
the positive legs are twisted together
on the inside. So now what we need
to do is we need to connect the LEDs
to the switches. And the way we're
going to connect the LEDs to the
switches is first we're going to take
some of the red wire that we had in
our kit, and we're going to strip off about half
of an inch of that red wire. And we're going to
feed that red wire through the top connections. There's little
tiny holes on each of those connectors on
the back of our switches, so we're going to trying to run
this wire through those holes. And this is probably the
trickiest wiring part in the entire bot,
because you have to bend the wire in a sort of
a large loop or a hook shape to get it to go through both of
the holes in each connection. So that's why we've got our
trusty needle-nose pliers there. And it does take a
little bit of doing, but you can get it to go
through both of those holes. And it does help to make
sure that the connection will be a good one. So there we go. We got the wire to feed
through both holes there. So then I just bent the
wire up at a 90 degree angle to the connector that
it's going inside of, and I'll zoom in
here just a bit just to make sure you can
see what's going on. And in order for this particular
[INAUDIBLE] bot build to work, we have to make sure that those
wires are crimped, or bent, very tightly against
the contacts. If there's a lot of
space in between the wire and the contact, the bot may not
function the way we want it to. So we're taking our
needle-nose pliers and getting it into
those tight spaces between the wire
and the contacts and bending those wires tightly
against the connections. And we're going to
our LEDs to make sure that that connection
is actually a good one and that power is flowing. So the next thing
that we need to do is we need to trim our
wire down just a bit. So we're going to cut out about
two inches off of our wire. The wire that's remaining should
be about an inch and a half long, and we're going
to take off about a half an inch of insulation
from that wire. So again, that's a 22 gauge
wire, so it's really narrow, so we'll use the smallest
hole on our wire stripper. And these are really
low wire strippers, so you have to twist
them a little bit to get the insulation
to come off. OK, so now we have
our red wire there. We also have the red wire
coming from our battery. So what we need to
do now is we need to connect our red
wire from our battery to the red wire
we just connected to our single-pole
double throw switches. We're going to take a little
bit more insulation off of this wire, so we also
made it a little longer. So it's about two
inches long, and we're going to take about 3/4
of an inch of insulation off of this wire with
our wire strippers. And you've got to be
careful, because this is a stranded wire. It's not solid, so it's easy
to break the strands when you're stripping it. So you want to take your time
to pull the insulation off carefully so that you have all
those electrically conductive strands still connected. So then we're going
to take those strands and we're going
to take that wire and we're going to wrap
it around the solid core wire, which is the one we just
connected to the switches. And the best connections
are really tightly wound, so we want to make sure
that all of those strands are very tightly wound around
that solid core copper wire there. And so that's going
to make it easier for us to connect the positive
side of our battery to our LEDs and to other
components, as well. So we're going to take
our LEDs, and we're going to connect the
resistors to the LEDs. The resistors prevent the LEDS
from taking too much current and burning out. So again, we're going
to put the resistor leg at about 90 degrees
opposed to the LED leg, and then we're going to just
wind it around the LED leg. And we want to wind it around
at least four or five times, if not more, to
just make sure we've got a really solid contact
connection with the LED leg. And again, that's
the negative leg. And the resistors can go on
either the negative or positive leg, but in this video, we
chose the negative legs, which are the outside ones. So again, just twist
it all the way around, until it's nice and
firmly connected. It's important that those loops
that we make with that resistor leg are very tight and firmly
attached to the LED leg. OK, so now that we
have our LEDs set up, we can begin to connect them
to the red wires which we just wound around. Before we do that,
we're going to just test to make sure everything works. Let's move it here
so you can see it. OK, there we go, yeah. So we're getting power
through the wires, and we'll try the other side. This just makes sure that
we've wired our LEDs correctly. OK, so we have. And this is a low enough
voltage circuit and low enough current circuit that we
can just use our hands to connect these things. OK, so now let's
connect our LEDs. Now that we know that power
can flow through there, we're going to try
and wrap our red wires around our LED
positive legs, which are the center legs there. So we're going to try to
twist everything together, and this may be a
little difficult. So if it is, you can always
take your needle-nose pliers and just crimp it on
there and make sure that the wires are
connected tightly. Now, the better this
connection is, the more likely it's going to be reliable,
so it's really important to make sure that
connection is solid. OK, once we've got those
wires twisted together and our LEDs are there, we can
take a piece of aluminum foil and wrap it around just to help
ensure that the wires are going to stay solidly connected
and they conduct power. Now, you don't necessarily
have to use the aluminum foil. It's just an added
precaution, but basically it allows to make sure if
there's any loose wire connections there, that we still
get electrical conductivity. But again, you don't
necessarily have to have that. OK, so now we're going to take
some insulating material, which will be electrical tape. We're going to wrap
it around our aluminum foil and the twisted
together wires, and that should help to hold
everything in place so that we have a reliable connection. And it's just a little
bit out of the screen. There we go, moving it
back into the screen. And you want to wrap that
electrical tape as tightly as possible around
that connection to help hold everything
snugly in place. So now what we're
going to do is we're going to connect our resistor
leg and our black negative wire from our batteries to the two
open terminals on our switches. And depending on which
terminal you connect it to, the switch will turn
it on or turn it off. And so one thing you
want to be careful of is, you don't want
to leave it on there too long, because
when it's turned off, you can actually
short the circuit, and that will cause
the wires to heat up. But it does allow
us to test the LEDs and to make sure that all
of our connections are good, and they are. So we're going to hot-glue
the red wires, which are the positive terminal
wires, and that'll keep them from moving
around and hold them against our single-pole
double throw switches there at the top.