Step 2: Build the Electronics

I highly recommend etching a PCB for this project. They are more resilient and reliable than perfboard (IMO) and therefore more suitable for use in a childrens toy.

Start by etching your board using your preferred method. I won't go into detail here - check out my other instructable on how to use the toner transfer method to make a PCB.

Now, populate the board using the parts list and board layout as a guide. Start with the ICs, and then the resistors and caps. Make sure the two electrolytic capacitors are installed with the correct polarity. When soldering the LEDs, bend the leads a bit so that the LED is flush with the edge of the board. LEDs are polarized too, install the the right way! Finally, solder in the potentiometers and the 9V battery clip.

Two of the switches will have three wires, one of them only needs two. Solder about 2-3" of wire onto the pins of the switches, and finish them with heat shrink. Note that the body of the switch must not be longer than the standoffs, or they won't fit!

Cut a piece of perfboard equal to the size of the PCB (3x3 inches). Drill holes in the four corners that match the holes of the PCB. Drill three more holes that match the shaft diameter of the switches. You can put these three holes wherever you like; I chose to put them in a line. Mount the switches on the perfboard, using one of the supplied nuts. Save the second nut for later.

Now it's time to solder the switches onto the PCB. Match up each switch to a position on the PCB, and solder its wires in place. Make sure that the middle pin on each of the switches with three wires goes to the middle pin on the PCB. Soldering can be tricky, since you have to solder to a pad on both sides of the board.

With the switches installed, you may link the perfboard to the PCB using the standoffs. The perfboard should be mounted as shown in the picture. I used flathead screws on the perfboard side, so that the screw heads wouldn't cause the fabric to bulge. Don't tighten the screws completely just yet though, as you'll need to remove the PCB from the perfboard for mounting inside the robot's head later on.

Solder long wires to the leads of the photocells, and finish the joints with heat shrink. You may also want to add a glob of hot glue to where the leads connect to the package of the photocell for added strength.

Finally, solder long wires to the speaker terminals and finish the joints with heat shrink.

Don't solder the photocell or speaker wires to the PCB yet - you need to mount them inside the Thingamaplush's body first.
now make two of those and let them 'comunicate' :D<br>that ought to be fun :D
me you could send the listing of the materials? thanks
Can the speaker be replaced with an audio jack?
Not directly. You can connect an audio jack to the input of the audio amplifier, on pin 3. The other pin on the jack goes to ground.
you are a genuis, i just have one question, does it really move or do you move it?
Thanks!<br /> <br /> No, it doesn't move.&nbsp; It does beep, though!<br />
You sir, are a genius worthy of being inducted into the instructables hall of fame.<br />
Well thanks!&nbsp; I don't think I've earned such accolades just yet, though!<br />
btw, did people stare at you strangely at the park? When i was playing wiht Bebot (http://www.youtube.com/watch?v=KFG7-Q0WI7Q) in Joe Ann(while my mother shopped for sewing materials), people stared at me like I was a weirdo. <br />
I'm not sure, I wasn't really paying attention to anyone else.<br />
Very good job, it's really nice. But I have a question,<br /> What IC corresponds to U2?
Whoops, sorry!&nbsp; That IC is the brain of the operations, an Exar XR2206.<br />
Great ! , thks very much ;)<br /> The answer that i esperate xD
I&nbsp;need to see more of Thingamaplush's&nbsp; adventures....can't...stop......watching....
&nbsp;Success! &nbsp;If you make your own, you could make your own adventures... &nbsp;;)
Ooooo - maybe they could video conference!
NEED&nbsp;HELP!!! Is this PCb double sided?<br /> can someone send me a PDF of the pcb
Yes, it's double sided.&nbsp; To view it, go to www.cadsoft.de and download the freeware version of Eagle.&nbsp; That way, you can print out the PCB design from the original vector artwork, at the correct size, rather than from a PDF.<br />
&nbsp;Every time I click your download link it downloads a .tmp file that cant be opened, this is the same for both the thingamaplush.sch and thingamaplush.brd
It's a bug in instructables.&nbsp; Either rename the file that downloaded, or right-click the file, choose &quot;save as...&quot; and pick a name for the file.<br />
&nbsp;tried renaming it as an .sch file but it still won't open. Is there somwhere else I can download the files.<br /> <br /> I'd be really grateful if someone emailed me them<br /> <br /> rayads786@hotmail.com<br />
This is super cool, I'll remember this for when I&nbsp;manage to produce some spawn.<br /> Though I&nbsp;have to be honest, when I&nbsp;first watched the video I thought &quot;Dang I&nbsp;hate to be caught with that thing in my carry on at an air port.&quot;.&nbsp;
It's a great gift for Significant Others as well!<br />
so how much would all this cost?
Hmmm, maybe around $25-$30.&nbsp; It depends on how many of the parts you have lying around.<br />
Instead of sewing up the battery pack why dont you put velcro or buttons<br /> <br />
I sewed it shut so that my daughter wouldn't tear the battery out.&nbsp; But of course, if there is no danger of toddlers performing surgery then by all means use a less permanent method of closing it up!<br />
yup i did your right <br />
&nbsp;Well, you can use it for something else then!
Coolest toy ever. 5*. Excellent work man, excellent work! I can't believe I didn't see this and vote on it!<br />
&nbsp;Thanks! &nbsp;Maybe next time... &nbsp;;)
I'll subscribe so as to not miss something :P<br />
jim244, the ears are just knobs for the potentiometers. They were bought from futurlec as well, and were part number "KNOB7"
ok uhm my country doesn't have the 1uf capacitor ceramic and mylar so i brought .01uf the problem is how will i connect it to make it 1uf
Well there's not much you can do unless you connect 100 of those in parallel. And that, of course, is not really an option! If you use that one in place of the 1uF, the modulation rate will be 100 times too fast. You could put in a 0.1uF capacitor - it would only be ten times too fast. It will at least be useable. But, try to get a 1uF capacitor if you can. They are pretty common...
typo it's .1uf can i connect these in parrallel
You can. You'll need 10 in parallel to get the full effect, but 2 or 3 should be enough.
ok thx
what are the caps for anyway
The caps are part of a very simple RC oscillator, consisting of one cap, a Schmitt trigger inverter, and a resistor. Also, don't forget to vote for me! :)
already did even before you asked
Thanks!! :)
what will id o if my pot2 switch only has 3 pins (does not have the 2 at the back)
Well, you could get a different pot, or hook up a separate power switch to those pins.
what kind of pot<br /><br />
&nbsp;A switched pot. &nbsp;Futurlec part number POT10KSWITCH is what I used.
i can use pot10kswitch&nbsp; for pot 2<br /><br />
i went to the store again and only got a 6 pin can i bent the middle one off or could you help me edit your board<br />
Ummm...&nbsp; I think you got the wrong thing.&nbsp; If your pot has 6 pins, it's probably a dual potentiometer (that is, two pots controlled by a single shaft).&nbsp; Confirm this by testing the pins with a multimeter before doing any damage to the part!<br />

About This Instructable




Bio: By day, Jeff is the Jack of All Robots at Clearpath Robotics. By night, a mad scientist / hacker / artist / industrial designer wannabe!
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