Finished the Leave Me ALONE! box, p2

Where was I? oh yeah, the wiring it all up:

And there it is.. all done! Little bit of hotglue to secure the freeform "brains" in place for all the shaking in its future, and using the red wired purposely soldered in a "too high" arch (so that the wires would pin the brains in place when the baseplate was screwed down.. sneaky, huh?!)

 

All that was left to do for now was to put a fresh battery in, bolt it all up tight, and add a little red ink to the silver paint I put in the writing on top.. and it was finished!

 

 

I'm taking a break on the LeaveMeALONE! box for a while, let it sit in glory for a while on my "neat stuff" shelf. But there ARE plans for further additions! After the relay mod, the DPDT switch is really not being fully used anymore.. and I have ideas for what to do with the "off" position set of posts. Things it can do when its technically "off"... like punish people who peek. But you know the saying: a pic is worth 1000 words, so lets save some space:



From Top to Bottom: micro piezo buzzer, mercury tilt switch, submicro pager vibrator motor. Oh.. that thing on the right? Just a little something I yanked out of an old CD-Rom player.... thats mah LAYZOR diode!!

Basically; if its "off" but the tilt switch on underside of door gets closed, all hell breaks loose on the cover itself- the buzzer is piercing at 9v, the pager motor is insane buzzing (feels like getting shocked, actually) at 9v.. and the laser.. well.. I'm not an EVIL guy, who wants to blind anyone or anything, so I was thinking more for internal effects.. a laser "tripwire" spotted when you open the lid for a peek... or a servo mounted cylon scan sweep inside.. something. I dunno. but nothing EVIL ( maybe I'll save it for mounting on frickin' sharks heads!!)

Finished the Leave Me ALONE! box

For those who may not know yet, the "Leave Me ALONE!" box is like a "most useless machine" found everywhere... only angrier. It builds up a bit of rage, then turns itself off.This started as an electronics self test to see if I could make an electronics circuit from scratch that could do what I wanted it to do: slowly build up the speed and power of a vibrating pager motor in a building ramp up of "rage", and then activate the arm to cycle the whole machine back off, and put the arm away.

It took a lot of on the breadboard experimenting to get it to work just right. Turns out it takes 3 transistors and a voltage trigger to allow all of the different things to happen. Here is the final schematic:



So you see, now the switch does not directly power the arm motor (far right).To the left is the vibrating motor controls, to the right is the relay arm control, and in the center is the heart of it all: a Big 'ol resistor capacitor RC "thing", that does all of the slowly building up voltages that the rest of the circuits works off of.

 

 

I learned a lot about RC style systems, mostly from a ration of failures in trying to get this to work. See; the resistor slows the charge up of the capacitor (to about 3-5 seconds), meaning that that 4 way intersection in the center will go from 0 to 9 volts in a slow climb. At first, I just tried to have the vibrating motor powered directly at that intersection- it didn't work; the motor was a "path of least resistance" for the power to escape through after passing the resistor. similarly, the intersection would not turn on the relay at around 5v as I planned, because its coil acted the same way as the coil in the motor... so a RC wont ramp up a charge with a 'load' present, and in the end, Neither will do anything. Check! If I had gone to some electronics class or something, I might have been told that at some point... and not known what it meant, exactly. BUT with this practical experience, now I get it!

 

So both the vibrator motor and the relay needed a "buffer" in between. Like a transistor base. The rising voltage will turn on a transistor more and more as it climbs, meaning the thing the transistor is powering (from another route of power)- so, in dumbdum terms: the RC intersection cannot power a thing directly, but can power a knob to adjust the power.

 

The vibrator motor worked with the intersection powering the base of a single NPN.. but the motor peter'ed out (poor Peter.. what did he ever do to get that term named after him?!) at around 4v.. oscillating the circuit.. like the transistor was "floored" already, and couldn't push any more power. So I doubled it up- a "darlington transistor pair" apparently- two NPN's stacked up. At first I thought they would both just drive the motor "in parallel", but apparently this "in series" arrangement works better- not sure why if the first NPN was floored in the first place...? But anyway, 2 NPNs and the motor will power itself right up to 9v and self destruction... if need be.

 

That's where the relay comes in. I had to add a special little hard to find chip: a 1381U voltage trigger (salvaged from some solar engine parts I bought- the U was unusable for those, as it triggers around 4.5v) to keep the NPN from just turning on the relay as soon as possible (which turned out to be MUCH too soon!) So now, with the voltage trigger waiting until it reaches its trigger levels before enabling the NPN, the vibrating motor gets more time to ramp up to a really alarming level. The diode was a little trick I learned to stall the trigger even longer; as the diode "keeps" about .7v as power goes through it, meaning the voltage reaching the trigger is lower than the actual voltage in the capacitor: an extra little delay.

 

I drew this sketch AFTER I had moved this here and there all over the breadboard to get it right, so lets look at the breadboard, wired to control the box externally:

What you see is the relay, the NPN by the relay, and the trigger in the foreground, powering the NPN. The Black and Red jumpers leading to the box went to the motor, the red and green in the background came from the battery/switch. The RC and vibrating motor NPNs are tucked under the Cap (built up previously), and the pager motor is the white blob tucked behind.  Lets see if it works!

 

Looks good from here! (the diode was missing, so the shutoff is rather quick at this stage)

 

Well, with that all said, all that's left to talk about is the neat little arrangement of the relay and motor wiring. You may note that there is no polarity reversing taps, nor a back stop switch to pull the arm back.. yet it pulls back anyway! This is where I start getting DEEP:

 

Its all about Back EMF. Or, more specifically, "Motor Kickback". As a motor is spun, it is also generating its own little power, because the coils are spinning near a magnet. This is the Back EMF (electromagnetic force) that is normally found in all running motors. If the power to the motor is suddenly severed, the Back EMF, which was generating power in the opposite polarity discharges as the motor coasts to a stop. Motor Kickback is a BAD thing in normal electrical engineering (causing belts and such to snap, or motors to lurch in their mounts with the violence), and is usually eliminated with a shunting diode to let the back emf drain away to ground (its just a reversed spike of power that lasts only a moment), found as a diode reverse wired between the motor leads.

 

So Motor Kickback = BAD. Unless you want the motor to kickback! And that's what the motor does in my Leave me ALONE! box. This is why the relay uses both contacts to connect and sever both the ground and the power of the motor simultaneously; with both wires suddenly disconnected, the back EMF has no where to go.. but to drive the motor backwards for as long as it lasts. Which turns out to be just enough! I learned all about this in some other experimental research I was doing, involving scavenging back EMF for usable power... but that's for another time. Whew! {/break DeepMoment;}

 

So, how to pack all of this circuitry in this little 4" x 6" box? printed circuit board? Psh! the Junkbots book taught me about "freeforming" components together.. and I really LIKE the way it looks!

 

So, there it is: all the stuff that was on the breadboard. just SEEING that makes me go "oh, cooool!". If it was going to essentially be the brains of this little box, it might as well look like some brains.. robot brains, of course!

Go ahead! zoom in on the intricate interweavings of all those prongs, each doing its own little thing. To the left is the original RC/vibrating motor driver, in the middle is the newer Trigger/NPN driver for the relay, and the relay itself. The little bits of salvaged wire insulation over some of the prongs helped me remember which ones were switched power and ground. but in the end, I thinks its a bit of a work of art, if I do say so myself.

It was Freeformed into this particular shape to sit neatly in an open spot within the box, as seen here. And thats the neat thing about freeforming: no way a printed circuitboard would fit in there! Plus, it leaves all the stuff inside out of sight from the peeking door, AND leaves me more room for more goodies if I decide to add them later.

All that was left was to wire the power and the two motors in... hmm looks Like I've reached the end of my photo uploads for one post. To be continued!

 

 

 

LEAVE ME ALONE BOX- Vibration add on project.

I really love Instamorph! The stuff is just amazingly useful, and has an additional feature I plan on using from now on, now that I have discovered it: its "refusal" to bond putty state IM against cooled plastic state IM! Why is this cool?! Well, let me show you:

Here is the new vibrator install. It is placed center line, on the heavy end of the box- to make the mass of the box jitter around more (in theory). To the left of the motor is a big new section of IM, thats just a holding frame for the 9V battery, seen socketed in it. I figured this was needed due to the violent vibrations the box would now undergo, plus, the battery kept slipping loose anyway. Added bonus, my thumbprints are now a part of the box for posterity!

 I was originally planning on stuffing the large Cap in the square void left available, but found the vibrator motor fit just fine. So, I got a big glob of Instamorph all warm and clear and playdough-like, and squished the motor into it, then squished the still malleable putty (now more like modeling clay consistency as it cools) into that hole. Since the warm newly installed glob was warm, yet the white stuff to either side of were cold, they didn't interact with each other. Why is this cool?

Because if you notice, the bottom picture glob around the vibrator is already molded to fit in that socket, and YES, it is still removable! Notice the grooves on the bottom, that match the bump lines at the rear of the box. That means this motor is now socketed into a custom molded plug, to fit snugly in its place, yet still be removable! Don't believe me? well, watch:

Its a nice solid click, due to the shape of the plug and socket, when it clicks in, it holds it solidly in place (notice that when trying to remove it again it picked up the whole box). no glue, screws, etc required! how many other mounting methods can claim the same features?! NONE! this stuff is future technology material at its best.

After mounting the motor, and seeing that nothing more was needed to secure it inside the box, it was time to permanently wire the little RC engine that would drive it.




I was trying to go for compact and small, and wound up getting Super Cool looking as well! Bonus! Like my 1wing Solar engine, all of the electronic components fit between the Capacitor prongs, so if I can find room for the Cap, all that's left is to wire the additional wires up.

 

I cant decide if it looks High Tech? or Vacuum Tube Retro? Regardless, its super neat looking (IMHO), and I get a little beam of pride knowing no circuit board was required.

With the intricacies all done, it was now time to test it! lets set it up, place the camera, and see what happens when I (electrician term) "Turn on the Juice, and see what shakes loose!"

 

Yup! I'd say its working OK. and there seems to be enough power- electrical, transistor supplied, motive mass, whichever power you may have thought I was talking about!



PAGER VIBRATOR RAMP UP CIRCUIT

Success! After maybe 5-6 different tries, I have a circuit that works the way I wanted it to!

This is a big achievement for me, as this is the first time had an idea of what I wanted to do first, then successfully designed a series of electronic components that would make it do it correctly! Up to this point, I was either following circuit drawings, or mimicking other circuits, like the solar engines.

This also taught me some more details about capacitors. I already knew how to trickle charge a large Cap up in voltage slowly, either with a trickle coming from a solar cell, or through a high ohm resistor... BUT I never had any practical idea of how to USE that, other than to voltage trigger it to dump it through a motor... making the cap merely a second hand battery.

Now, I know how to make it a timer as well! This is an RC style electronics trick, which most electronics guys would already know about, but I learned it the hard way... as RC to me meant "Radio Controlled" :)

Anyway, here's the circuit, drawn on an index card and definitely going into my "don't forget this trick!" index card box.

So, it took me a few tries; The Cap here, the Cap there, across the motor leads, etc etc.. and it never worked. The Cap wouldn't charge up if there was a motor there to hog all the power, apparently. So, I eventually tried an NPN Transistor between the Cap and motor, hoping that the Base wouldn't "hog" the power from the Cap, and that Base, as it rose in voltage along with the capacitor, would "throttle" the power waiting at the transistor Collector (not sure on the terms yet). Turns out, that was the trick! The capacitor was now "separated" from the motor, the motor getting its power from the transistor. Simple. Sorta. The transistor seemed to peter out with the motor around 5v, and there was 9v there.. so maybe I had reached the limit of what that tiny transistor could "throttle".

SO... hearing about this trick called a "darlington transistor pair", where you simply double up the transistors to get them to supply more working power. THAT was the final problem solved!

 

So, right now that resistor is 1k ohm.. and the ramp up of the pager motor is pretty quick... oh, wait, I didn't show the video of that yet!



Heh.. you cant see it, but the soldering iron resting in those mechanical fingers was vibrated almost out of its holder! Wow that vibrator is strong (when forced with much more power than it was ever designed to take.. hehe). Its out of focus, but I got the gauge in the background showing the voltage rising in the capacitor... It peters out around 7v.. meaning the other 2 is probably what the transistor pair is "stealing" but anyway, it perfectly meets the power requirements to energize the 5v relay after a few seconds delay-  that I plan on adding to my LeaveMeAlone box to give it more "activity"

As I was saying, the resistor causing the delay is 1k Ohm, which is a little too fast I think, but when I tried a 10k ohm, it took too long. So I'm guessing 5k Ohm or so will let the box sit inert for maybe 3 seconds before the first rumblings... then its On like Donkey Kong!! as they say... at least as those as old as I am used to say. heh.

So that's it for today. learning stuff. taking notes. almost vibrating a hot soldering iron into my lap. The usual.

THE MOST USELESS MACHINE

I call mine the "Leave Me ALONE" box, because of what it does, and also because it knows what the rest of the world calls it. Basically, this is a simple device that will make you smile, simply because its only purpose is to turn itself back off if anyone hits the switch.

I got the Idea from Instructables, MakeMagazine, Solarbotics and YouTube stories/ads/videos about it. Its really sort of a "Meme"- like a Viral Idea that spreads like a Virus everywhere rapidly, as in all the articles listed above.

It is a really simple thing, both to build and to wire, yet it behaves like there is more in there going on than there actually is. All that's inside is a double pole, double throw switch, a motor, and a push button switch than can be wired Normally Closed.

Most of the Useless Machines you see online are rather big.. like cigar box sized.. which didn't appeal to me very much. I figured I could make one out of a little radio shack Project box, with a micro DPDT switch, and a mini geared motor I got from solarbotics.

The hardest part was cutting the door away with a hacksaw... carefully slicing a section of the top off, yet leaving it intact enough to replace and hinge with some ubiquitous HotGlue. It makes a really nice spring loaded hinge- that keeps the door flap closed and slammed shut. No springs/screws required!

Seen here painted Silver... I don't know why, to match the painted writing in the channels made with a hot soldering iron (used) tip on the top I guess.

 

After getting it all built and wired up, I was surprised to find this box.. roughly the size of a 5 x 8" index card, had plenty of room inside still!

 



Hrmm Its a little hard to see, but lets try to give a Tour: The 9Volt battery is the 9 volt battery ( :P ), the red thing is the underside of the DPDT switch, the big white Square blob is the mini "Geared Motor"- a motor with a built in gearbox for more torque, the blinding white arm thing is the arm, made of that Instamorph stuff, and hiding under the axle of the arm, is the black contact switch. The paperclip coming off of the right of the arm is what hits the contact switch, and what can be easily bent to adjust the stop portion just right.



If you look closely in the top right corner, you'll see another white blob... that's some more instamorph, using that corners screw mounting posts as a "grip", and wrapping around the back end of the motor case of the gear motor to make... an instant BRACKET. MAN that stuff is handy.. I don't know HOW I lived without it. I guess I would have hot glued it before.

 

So there it is, the silly Leave me ALONE box. I brought it to work, left it on my desk, and everyone couldn't resist but to NOT leave it alone. They all loved it. Oh! I almost forgot the other goofy detail. Notice how all the internals are off to the side, not visible from the door, well, since I knew everyone was going to look inside and not see anything. I figured Id give anyone curious something to look at:

 

 

With all that extra room inside, I feel tempted to add some more "things it does" to it. One of the first ones will be a hidden on/off switch- sometimes it chatters a bit like a ticking time bomb if it gets slammed around a bit, and the arm starts bouncing on the contact switch sping.

 

Other ideas are:

- A vibrating pager motor wired so that when the switch is in the "left alone" position, but the door gets opened (tilt switch on its underside?) the box will vibrate angrily!!  :) (hmm but then I would have to make the box more drop-proof)

 

- A Large cap acting as a time delay, and ramp up for when the switch is engaged- the switch wont directly move the motor, but rather start to ramp up power in the Cap- slowed by a resistor to take a bit of time, the rising power making the pager motor vibrate more and more violently as it gets up to about 5v: the voltage to make the mini relay inside energize- initiating the whole arm thing- rather than the Switch. (this will take some experimenting, learning how to make a capacitor charge up, and at the same time drive the motor for the vibrator under the varying voltage levels).. sort of a "b.b.b.bb.bb.bbbbbbBBBBBBBRRRRRRRRWOOOOOAAAAAOOOOOWWW!!!!*click!*-arm smacks switch, arm retracts, everything stops. vibrations slow down and stop (as CAP drains away the remainder energy)

 

-toothbrush heads chopped off, and holes hut into metal base plate so the bristles stick out on each side of the base as feet- one angled one way, the other the opposite way. IF its not too heavy, as the vibrating motor gets going, the box should spin in place as a "bristlebot" on whatever its sitting on! Placing the weight of the vibrator will be key to this one, but its just a dream at this point.

 

 

So you see, its these ideas that keep me interested in continuing to tinker- if I didn't have these crazy ideas I wanted to try, I wouldn't be quite so mad scientist enthusiastic about it all!!

 

I'm going to go work on that "getting more violent" vibrator circuit. Be back soon with results, if any.