+ (section
+ :title [battery wiring]
+ (subsection
+ :title [leads]
+ (subsubsection
+ :title [strip]
+ (p ["leads" are the wires coming out of the battery pack.
+ prepare the leads of the batteries by stripping them and
+ placing heat shrink on them.
+ your battery packs are not attached to your deck yet,
+ but that will be the next step.])
+ (figure :legend "batteries / prepare leads / stripping"
+ (video
+ :file "2-batteries/0-prepare-leads/0-strip.ogv"))
+ (enumerate
+ (item (bold [do not pick up batteries by their leads!]))
+ (item [strip the leads a tiny bit at a time.
+ keep stripping until a total of an inch is stripped.
+ the leads are made of tons of tiny wires that will
+ tear apart if too much insulation is stripped at
+ once.
+ wire made of a bunch of tiny wires
+ is "stranded wire".])
+ (item [strip both leads of both batteries.])
+ (item [then place heat shrink on every lead.
+ make sure the heat shrink is either clear or matches
+ the color of the lead.]))
+ (p [check])
+ (enumerate
+ (item [should you pick up a battery by its leads?])
+ (item [should you strip the leads a large amount at a time?])
+ (item [what's the name of wires made of a bunch of tiny
+ wires?])))
+ (subsubsection
+ :title [wrap]
+ (p [do the next 2 sections with just one lead at a time.
+ wrap, then solder one battery lead before moving on to the
+ next.
+ wrap the stranded wire around a solid core wire, as shown
+ in this video.])
+ (figure :legend "batteries / prepare leads / wrap"
+ (video
+ :file "2-batteries/0-prepare-leads/1-wrap.ogv"))
+ (p [the solid core wire is the stiff short wire.
+ it is much easier to poke into the breadboard.])
+ (p [check])
+ (enumerate
+ (item [why are we using a solid core wire?])))
+ (subsubsection
+ :title [solder]
+ (p [do this next section and the previous with just one lead at a
+ time.
+ solder the stranded wire and solid core wire, as shown
+ in this video.])
+ (figure :legend "batteries / prepare leads / solder"
+ (video
+ :file "2-batteries/0-prepare-leads/2-solder.ogv"))
+ (p [soldering is the process of joining 2 metal things with
+ solder.])
+ (enumerate
+ (item [use the helping hands to grab the wires and hold them in
+ place.])
+ (item [clean off the tip of the soldering iron if it has been
+ sitting still for a while.
+ this cleans off corroded metal.])
+ (item [apply some solder directly to the tip of the soldering
+ iron.
+ this creates a pool of solder on the tip.
+ we will use this to transfer heat to the wires.])
+ (item [put the soldering iron up to the wires.
+ we want the wires to be hot enough to melt the
+ solder.
+ at the same time, poke the solder into the wire.
+ the solder will start melting and quickly spread to
+ hot parts of the wire.
+ there will be smoke.])
+ (item [move the solder away, then move the iron away.]))
+ (p [check])
+ (enumerate
+ (item [should the wires melt the solder?])
+ (item [why should we clean off the tip of the soldering iron?])
+ (item [why do we put more solder back on the tip of the iron?])))))
+ (section
+ :title [motor wiring]
+ (subsection
+ :title [leads]
+ (p [attach leads to the motors to supply the motor with power.])
+ (figure
+ :legend "motors / leads"
+ (video
+ :file "3-motor-assemblies/0-leads.ogv"))
+ (enumerate
+ (item [strip both the green and yellow wire on both ends.
+ strip one side only 1/8 inch.
+ strip the other side about 1/4 inch.])
+ (item [use the end of the wire stripper to bend a hook in the wire.
+ make this hook on the side of the wire with a smaller
+ exposed section.])
+ (item [do not bend the wire so that the exposed wire runs alongside
+ the sheath.])
+ (item [put the hooks through the tabs on the motor.
+ make sure to place the green and yellow wire on the
+ correct side of the motor.
+ match the side of the motor that already has wires
+ attached.
+ wrap the rest of the wire around the motor in order to
+ keep the wire from falling off.])
+ (item [once the wire is in place, wrap solder around the motor tab
+ and wire.
+ heat up the solder, motor tab and wire with the
+ soldering iron.])
+ (item [test the solder joint with the 9v battery.
+ touch the battery leads to the motor leads.
+ make sure the 9v battery is on.
+ if the motor moves, the solder joint is good!])
+ (item [get section of electrical tape, roughly 100mm
+ (about 4 inches).
+ slide the middle of the tape under the wires.
+ this tape will keep the solder joints away from the
+ metal band around the motor.])
+ (item [the zip tie will hold the wires to the motor.
+ wrap the zip tie on the round part of the motor where
+ it meets the square portion of the motor.
+ this will provide mechanical support for the solder
+ joints.
+ once the zip tie is wrapped, use wire strippers to cut
+ off the excess zip tie.])
+ (item [cover the solder joint with hot glue.
+ this will further keep the solder joints from corroding
+ in the air's moisture.
+ it will also keep the joint safe from anything poking
+ in.]))
+ (p [check])
+ (enumerate
+ (item [should the electrical tape go between the wires and the
+ metal band?])
+ (item [are the motor tabs strong?])
+ (item [what are we doing to reinforce the motor tabs mechanically?])
+ (item [does hot glue make an electrical connection?])))
+ (subsection
+ :title [motor mount]
+ (p [now let's attach the motor mount to the motor.])
+ (subsubsection
+ :title [angle bracket to motor mount]
+ (p [first, attach the angle brackets to the motor mounts with
+ #6-32x3/8 inch screws.])
+ (figure
+ :legend "motors / mount / angle bracket"
+ (video
+ :file "3-motor-assemblies/1-motor-mount/0-angle-brackets.ogv"))
+ (p [if you cover up 2 of the holes on the motor mount, the
+ remaining holes look like a surprised face.
+ these are the holes to attach the angle brackets.
+ make sure the angle brackets on one motor mount are attached
+ in a mirror image to the other.])
+ (p [check])
+ (enumerate
+ (item [should the motor mounts have angle brackets attached in
+ a mirror image fashion?])
+ (item [why should the motor mounts have angle brackets attached in
+ a mirror image fashion?])))
+ (subsubsection
+ :title [motor mount to motor]
+ (p [now attach the motor mount with angle brackets to the motor.])
+ (figure
+ :legend "motor / mount / mount to motor"
+ (video
+ :file
+ "3-motor-assemblies/1-motor-mount/1-motor-mount-to-motor.ogv"))
+ (p [we will attach the motor mount to the motor using #4 bolts.
+ these screws are thinner than the #6 bolts we have used.
+ to clamp down on the motor, we will use a #4 nut.
+ the white side of the nut should face outward.
+ this section of the nut will keep the nut from jiggling
+ loose off the bolt during normal operation.
+ the head of the #4 bolt is a philips head, so we will
+ use a philips head driver for it.])
+ (p [check])
+ (enumerate
+ (item [is the #4 bolt thicker or thinner than the #6?])
+ (item [do you have a ratcheting socket wrench, or not?]))))
+ (subsection
+ :title [deck attachment]
+ (p [now that the motor assemblies are together, we will attach them
+ to the deck.])
+ (figure
+ :legend "motor / motor assembly to deck"
+ (video
+ :file "3-motor-assemblies/2-motor-assembly-to-deck.ogv"))
+ (p [when attaching the motor assembly to the deck, be sure to push
+ the assembly as far outward from the center of the robot
+ as you can while tightening it down.
+ this will give more clearance to the wheels of the robot
+ so they do not rub the deck.])))