they were about fans welcome back to the build over the past two episodes we've
dealt almost exclusively with the head arms take a look at the past two
episodes to see the work done on those now we're at the point where we have to
realistically start thinking about how we're gonna power all the servos that
control those arms and how we're gonna route the wires within the head looking
back in my BBA project I really loved that project it was one of my first
major robotics projects but the inside of that body is a mess the wires are
super tangled they're all soldered randomly to Rails I've had experience
with them pulling out of their sockets or becoming D soldered on their own so
with this build I really want to keep everything as neat and tidy as possible
no wires hanging around no wires I can get pulled out by the arms everything
tightly routed tightly packed and really neatly organized that's the name of the
game for this entire video so let's dive right in and take a look at what needs
to be done okay so the batteries for chopper are going to live somewhere in
the body maybe in the main body area maybe and the battery box is down by the
feet we can figure all that out later but the important thing here is that
they are not going to be in the head so we need to transfer the power to the
head and since the head spins we also need to use a slip ring a slip ring is a
device that uses a circular track to complete the circuit between two wires
allowing one end of the slip ring to rotate and keep the connection to the
other end this is a 12 wire slip ring we are going
to dedicate two of those wires to I squared C data communication between the
main Arduino in the body and the two Arduino in the head which are going to
control all the servos up there that leaves us with 10 wires for power I'm
going to use all 10 wires to transfer power to the head 5 for power and 5 for
ground so let's go back to our main diagram here and talk about what
actually needs to be powered in the head 24 volts are coming in and being
converted down to 12 volts these 12 volts will run the two solenoids the
linear servo that will push the periscope out and run the SBE sees which
power the mega scale servos pushing our head arms in and out of the head one
output of the 12-volt bus will also go to another step down to 9 volts which
will power the two Arduinos a second output from the 12-volt bus will run to
a 6 volt step-down this bus will run all our six volt servos three in each arm
and two for the doors an additional bus will be running five volts from the
Arduino to power tower neopixels so how are we going to set up this crazy power
house while still keeping everything as neat and tidy as possible this is the
wogo 5 port lever nut I really like saying that so I'm going to say it again
lever nut and what this is going to do is create a solderless bus for me so I'm
gonna be able to have one input going in here and it's going to charge the other
four ports in the same way and by using a bunch of these together I can create a
pretty intricate power house so this is kind of gonna be the star of our show my
goal is to use a whole bunch of these I bought 50 of them that should be more
than enough to get me through the head and I'm going to use these to create a
modular power unit like this this is the first one I already have it all wired up
and the goal is to have these be completely plug and play throughout the
entire head so if we look at this one this is actually the first one off of
the slip ring inside the head so the slippering power comes into here charges
these two ports positive and negative with 24 volts I have an output coming
from each one of those into that Pololu 12 volt regulator and then from there we
come to here where we have a huge port of 12 volt buses and the goal with this
is to keep everything completely plug in place so you can see all the permanent
wiring is done on this board and all that we're left with is jst connectors
on the input side and jst connectors on the output side so once this is plugged
into the slip-ring what I essentially have here is seven 12 volt power sources
that I can plug an AST connector into and then if I ever decide oh this board
isn't working out for me I can just unplug all the jst connectors take out
this hall port and replace it with something else and it really doesn't
affect too much down the line because all it is is these simple connections
rather than all of this intricate port stuff here so bottom line permanent
wiring is done and everything is on a more plug-and-play level from here on
out so I want to set up a few of these modular units throughout the head
and have everything that is going to be permanent already done and keep
everything super accessible for all of my servos and all of my motors so let's
take a look at how we're going to do more of these modular units ok I've
created three modular units here that'll sit on top of the four spindles of the
base of the head this green one here is the one that we just looked at here's
the slip ring where it's going to come through and come to the 24 volt bus step
down to the Pololu voltage regulator and then give us those seven 12-volt outputs
here one of those 12 that 12-volt outputs is going to go here to the blue
module which is going to have a step down here to six volts this is probably
going to be the first of a couple six volt buses this is going to power all of
our servos that are going to do the doors for the arms and the arms
themselves I think each arm is going to need one of these little ports up at the
top to control all the servos within the arm another one of these 12-volt outputs
is going to go here to this module which is going to have a 9 volt step-down here
the 9 volt bus is going to power the 2 Arduino I'm going to use two arduino who
knows for reasons that I will talk about later that could also change to an
Arduino mega or maybe a mega and a new no I'm still a little unsure here but
that's another reason why these modular units are great the Arduino is are going
to also supply a 5 volt power source to here and then this last little unit is
coming off the slip ring also and that's going to have our data connection to the
Arduino in the body this area here is for an mp3 trigger which will also be
powered by the 9 volts here so that's a lot to print and a lot to wire up but
let's see what that's gonna look like okay I got all the modules printed out
and wired up it was quite a bit of work setting up all of these jst connections
but there was a little bit of a calming feeling when I was doing it knowing that
once these are set up the rest of the works gonna be super easy and especially
with something as difficult as these head arms where I'm constantly changing
everything not having to deal with soldering wires and desoldering wires is
going to be awesome so I'm going to get all of these install
on the base of the head but before we can do that I need to install the base
of the head on to the body so let's change gears and take a look at that
okay up until now the gear here has been attached to the lazy susan using a 1024
screw in a nut these are never really secure and I don't like the idea of
mounting the head to a single screw so I'm going to replace them all with these
half-inch standoffs right here I have six of these for all of the holes in the
lazy susan and there are six recesses in the bottom of the base of the head this
will give me a nice secure fit that is also removable once this is put on there
we can install the slip ring I've built a very temporary bus here attached to
the main axle which will accept all of the wires from the slip ring and give us
power to the head from the body this will eventually be replaced by whatever
we decide to do for power distribution in the body but this will give us what
we need to test out all of this stuff in the head so let's get this all installed
and we can start putting the modules in the head okay we have the base of the
head installed on the top of the lazy susan we have the slip ring installed
into the base of the head that is wired into our temporary powerhouse and the
body and all of that goes to our new control panel here which also features
the wah go lever nuts it's a much cleaner setup than our last temporary
control panel we have 24 volts going in which is on a switch this goes 24 volts
to the body and this step-down gives us nine volts to power the Arduino from the
Arduino we have our ID squared C connection leaving here and going up
into the slip ring I also took this time to update this
servo holder here previously it was pretty weak it was just holding on to
that bottom ledge and it was really wobbly whenever we moved ahead and that
caused a lot of backlash and slop in our nod mechanism so I printed out a
two-piece version which fills up this entire cavity it's now super secure
there's no backlash there so this is going to work out great with all of that
wired up we can start installing our module power units here I have the first
one set up which is plugged into the slip ring here and stepped down to 12
volts I put in a little tester bus here so I could test each of the ports as I
go and I have a multi here and all the ports are reading as 12
volts so this is good next I installed the 6 volt modular unit
I bridged off one of these 12 12 volt outputs and ran it along the inside of
the spindle here on the base of the head if I power this on you could see that
that step-down is putting out 6 volts if we look at the input voltage we can see
it's 11.5 so that's just fine and last but not least here is the 9 volt side
I'll wire it up I bridged another output from the 12 volt side into this step
down to 9 volts this powers the 2 Arduinos this mp3 trigger and supply is
5 volts to this bus here which we will use for neopixels down the line I think
that's gonna do it for this video we've gotten the entire base of the head wired
up we have 24 volts 12 volts 9 volts 6 volts 5 volts 2 Arduinos an MP 3 trigger
a few step downs along the way so I think we're all set as far as power goes
for now one thing we did not address was the I squared C connection to the
Arduino Omega in the body that's what we're gonna tackle first in the next
video I don't think I'm quite brave enough to try that yet with the
craziness of the head arms so I'm going to develop the periscope next I have
some really fun ideas for that so stay tuned for the next video check out some
of my other projects on my channel and I'll see you next time
you