The Most Useless Machine EVER!

Step 9 Dead Bug Circuit Construction:

The circuit has very few parts so instead of making a circuit board or using a prototyping board I just soldered most of the components directly to the appropriate pins on the 555 chip.

This method of prototyping is called Dead Bug construction.  As the name implies, the finished results aren't very pretty and often resemble a dead bug.

You’ll need a fine tipped soldering iron, steady hands and basic soldering skills.

Keep in mind that you don’t have to dead bug the circuit.  Prototyping or perf board can be used for the final circuit, or just keep it on the half-size breadboard that you tested it on.

Comments

[bio88]

I wonder how hard it would be to make the servo rotate 90, hit switch, wait say, 10 seconds, then rotate/return to home. All initiated by a momentary switch! That would be cool.

[Frivolous Engineering]

A delay would be cool, but I don't know of any way of doing that without using a micro-controller. If anyone does know, please show how.

[FJMSoft]

SaskView... I'm not a pro, but, maybe an another 555 set for 10 seconds which resets or disables first one, maybe another toggle switch will be necessary.

[abvnatter]

capacitors. do your research. I'm not the best at this so please be safe. In one of my classes we were able to make LEDs pulse very slowly or quickly depending on what size resistor we threw in the line. I popped a couple caps by putting them in the circuit backward.

[BrunoG]

maybe with a transistor and a big capacitor connected in series
:-}

[bpfh]

an NE555 timer circuit would do a a great time delay - just wire the current wire that runs the finger output and plug that into the NE555 trigger... you could then turn it on, leave it on a table, wait until guests arrive and have a zombie finger appear from the box after 10 minutes!!

You could also implement the circuit with a PICAXE chip and you could make random reponses to the box, and program it to do other things (like the Useless Machine that after a preset number of times getting turned on starts spinning around on the desk before turning itself off! )

[garrickg]

i'm trying to troubleshoot my circuit. A big problem I'm having is the battery overheating, and smoking, even when the microswitch is pressed down.

[Frivolous Engineering]

Double-check how it's wired up. Most likely there's a short.

[Whizzman]

Since I couldn't find an answer to this question: How is C1 poled? 

[Frivolous Engineering]

The positive lead connects to pin 2.

[insane2642]

Hi,

I'm having problems with my servo, it only rotates in one direction.
I haven't modified it, and I can't see any difference between my circuit, and the ones shown here. BTW I am trying to use the 555 circuit, and don't really want to crack open my servo!

Thanks for any help.

[Frivolous Engineering]

It's possible that the timer is generating a usable signal for one direction but not the other.

Check and see which toggle position it's not working in and the corresponding resistor (R2 or R3).  Make sure things are wired up correctly for that part of the circuit.

If things are wired up right, then you can try changing the valure of the resistor.
If it's R2, try using a slightly higher value.  R3 slightly lower value.

[insane2642]

Thanks for your help.

I think what happened was the connections to the toggle switch were a bit dodgy. I got a soldering iron today and put them in, and now it works like a treat!

Thanks anyway, and thanks for the instructable!

[ihaveasubaru]

This is probably something i'm going to have to figure out myself because of my wiring but i'm curious if anyone can tell me the deal...

Everything is wired up perfect, exactly like Sask's schematic. Checked 40 times over...and for some reason it works with and without the micro-switch.

when the microswitch is in its normal up position and the toggle is hit, the servo rotates up, then the toggle is hit again and it goes back to where it was. it also works like it should in the instructable. hmm

It's not really problem im just curious if anyone knows the reason.
ok, Awesome instructable, thanks for the inspiration!

[Frivolous Engineering]

If everything is wired properly, and you keep the microswitch button held in, the servo will stop right after it's switched the toggles.  Release the micro and power is restored and the servo should move back to it's home position.

Sounds like power has been wired directly to the timer, instead of being switched by the toggle and micro...

[ihaveasubaru]

got it to work! thanks! awesome instructable...



http://www.youtube.com/watch?v=NPDU7pLXSDo

[Frivolous Engineering]

You're welcome!

[kingbling11]

 Mine wont work!!!

I have wired it matching yours (Switch in second configuration) (Pic of second machine) and it simply does nothing when i turn it on!!

I can make the servo wiggle about a bit by connecting pins 2 and 3 together with a probe. I multimeter tested the servo power and its getting 5.5 volts when the batteries are giving off 5.8.

Anybody got any ideas as to why its not working?
 Thanks in advance.

[Frivolous Engineering]

Check the polarity of the diode (white line is facing pin 6 on 555).
Make sure the servo is wired correctly.  If you get the ground and signal wires mixed up it will do that.

[breakspeare832]

What is C2?

[DerekMellott]

c2 was deleted, it was not needed.

[breakspeare832]

thanks for the info

[breakspeare832]

Could you please show how to wire this on a breadboard?

[maxximerus]

Hey, I've got a question.

I'm trying to build one myself. Ordered all the parts to make the circuit first. But now I'm wondering. The 555 has got 8 pins. 4 on each side. How do I know which pin is what? There are no numerbers what so ever on it.

When It's done I'll post a video of it. Just have to make it work first. haha.

[Razormann242]

maxximerus
 
There will be a small dot on the top of the 555, that will be the number one, pins facing down, left side, from there it goes 1234 and from the bottem up right side 5678. hope that helps...Ray

[Frivolous Engineering]

en.wikipedia.org/wiki/555_timer_IC  Right hand side, 3rd diagram down.

[jazzluvr]

my servo is only turning a 1/4 turn, everything looks right - even rewired twice to double check... same result.

any suggestions?

[poorsob]

I had the same problem.  I put another 15k resister in parallel with the 15k resister that was already there.  This turns it into a 7.5K and makes the stroke about 1/2 a turn.

[jazzluvr]

perfect. that worked.  thanks for the help. so the amount of current controls the amount the servo turns. 

[Child of Strife]

Heeeeeey... hi. im only 12 and, kind of new to all this stuff, have little supplies and a very low budget. my biggest problem is the whole soldering thing, is there some way i could dead bug it without a soldering iron? Or is there some other method i could use that does not require soldering?
thx,
Child of Strife-- [e-mail]

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[zakerid]

a switch with screw terminals would start you in the right direction.
like this one-
cgi.ebay.com/ebaymotors/TOGGLE-SWITCH-DPDT-20-amp-12-volts-2-ea_W0QQcmdZViewItemQQhashZitem35a63deea7QQitemZ230422343335QQptZRaceQ5fCarQ5fParts
using the modified servo without the 555 circuit would be the way to go.

[Child of Strife]

thanks, but, like i said, im very new to this stuff and i dont understand exactly what you mean by "modified servo," so if you could point out where i could find one of these, that would be great,
thx.
Child of Strife-- [e-mail]

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[Frivolous Engineering]

There's a bunch of 'ibles showing how, here's a good one:
www.instructables.com/id/How-to-modify-a-servo-motor-for-continuous-rotatio/

[Frivolous Engineering]

I suppose you could just twist wires on to the switches and use a small bread board for the parts but I wouldn't really recommend it.

[beware87]

I have a question about the servo it has 3 wires 1 black(i supose is for the -) 1 red(for the +) and 1 white (i supose for the conection 3 of the servo) am i correct?
Thanks

[Frivolous Engineering]

That should be right.

[crawbridge]

 Yes. The black will go to ground, 1 on the 555 chip, a yellow, which should go to 3 on the 555 chip and a red which should go to pin 4.

[fordman15243]

(Sorry, another stupid question coming...) Can you tell me where the black wire for the servo goes to on the 555? I can't see on the picture...

[Frivolous Engineering]

Black USUALLY is ground so connect it to pin 1 on the 555 chip  which is connected to the black on the battery pack.

[fordman15243]

ok, thank you! =)