Batteries Not Included? A Question on Self-Contained Power Supply
Midnighter
Posts: 13
I'm working on a major hobbyist robotics/artist piece of work. Mainly, it's a fortune-telling device built into a 15x15x15 wooden cube, one face open, varnished and treated to look like a Victorian-era watch-works kind of deal. The robotics and mechanics of the thing are to be kept simple and hidden.
Suffice to say, I do not want to have to have a modern-day electrical plug and cord trailing out of it looking to be plugged into a wall if I can help it.
Here's all the machine has to do, perhaps someone here can tell me if I'm outta luck or what:
1. Spectator puts a coin into a slot on the side, activating a little IR sensor to switch everything on.
2. The front of the display are two wooden panels/doors which now swing open to reveal inside a little lighted area.
Inside the area are two pinwheels, one on each side. They're just light-metal hoops with little celestial/Zodiac images pasted on their outer edge. These slowly turn revealing all the little shapes on their edges. Just behind them are each a bright-white LED light, mounted so that as the pinwheels turn, mounted on the same shaft with them is a little multi-colored wheel of acrylic--as the pinwheels turn, the color wheel turns with it, all in front of the LED's, making the colors change as well as the little images on the wheel.
3. In the middle of these pinwheels, mounted against the back partition, is a metallic "Tik-Tok" head which does nothing, no light-up or anything. A little brass ramp comes out from just under the slot mouth all the way to the front of the box, towards the spectator.
4. An mp3 player board plays a short one-minute piece of eerie-pretty music to go with the rotating pinwheels.
5. When the one-minute piece is done, everything stops. A single fortune-telling card, the size of a 2x3 1/2" business card, spits out of the Tik-Tok's mouth slot, sliding down the ramp to the spectator for them to take.
6. After about fifteen seconds, enough for the spectator to take the card, the whole thing closes up, the lights go out, and it's reset for another run the next time a coin is put into it.
Now, assuming that I only have to turn it on and leave it running for short periods, say a couple of hours, and it's not running non-stop, only as people are putting nickels into it when I invite them to, I would *like* ideally to have all this run off some sort of D-cell or C-cell batteries, etc.
So I need to know if I'm barking crazy on this, or if it's doable and if so how do I go about providing the connection between batteries and the rest of this menagerie.
Let's assume I'll use: two continuous-rotation servos for the pinwheels, the two white LED lights, the mp3 board and speaker to play a musical piece, the BASIC Stamp module running everything, two basic servo motors for opening the two doors, a low-voltage top mounted light to show everything in a dim yellowed tone (like an old machine might have), an IR sensor for the coin-op slot, and a very simple little motor or armature that just has to shove out a card one at a time, from a spring-mounted little box where the cards are loaded like a bullet magazine, so that as one is dispensed the weight loss makes the pile rise and 'loads' the next card.
Presuming I'm using all that for the total effect, but it's all for very brief or one-second operations, and that I'm not needing it to run constantly, can this be done on an independently-stored battery arrangement inside the back, or am I totally out of luck and I have to suffer having a twentieth-century power cable sticking out of a 19th-century-looking illusion?
Suffice to say, I do not want to have to have a modern-day electrical plug and cord trailing out of it looking to be plugged into a wall if I can help it.
Here's all the machine has to do, perhaps someone here can tell me if I'm outta luck or what:
1. Spectator puts a coin into a slot on the side, activating a little IR sensor to switch everything on.
2. The front of the display are two wooden panels/doors which now swing open to reveal inside a little lighted area.
Inside the area are two pinwheels, one on each side. They're just light-metal hoops with little celestial/Zodiac images pasted on their outer edge. These slowly turn revealing all the little shapes on their edges. Just behind them are each a bright-white LED light, mounted so that as the pinwheels turn, mounted on the same shaft with them is a little multi-colored wheel of acrylic--as the pinwheels turn, the color wheel turns with it, all in front of the LED's, making the colors change as well as the little images on the wheel.
3. In the middle of these pinwheels, mounted against the back partition, is a metallic "Tik-Tok" head which does nothing, no light-up or anything. A little brass ramp comes out from just under the slot mouth all the way to the front of the box, towards the spectator.
4. An mp3 player board plays a short one-minute piece of eerie-pretty music to go with the rotating pinwheels.
5. When the one-minute piece is done, everything stops. A single fortune-telling card, the size of a 2x3 1/2" business card, spits out of the Tik-Tok's mouth slot, sliding down the ramp to the spectator for them to take.
6. After about fifteen seconds, enough for the spectator to take the card, the whole thing closes up, the lights go out, and it's reset for another run the next time a coin is put into it.
Now, assuming that I only have to turn it on and leave it running for short periods, say a couple of hours, and it's not running non-stop, only as people are putting nickels into it when I invite them to, I would *like* ideally to have all this run off some sort of D-cell or C-cell batteries, etc.
So I need to know if I'm barking crazy on this, or if it's doable and if so how do I go about providing the connection between batteries and the rest of this menagerie.
Let's assume I'll use: two continuous-rotation servos for the pinwheels, the two white LED lights, the mp3 board and speaker to play a musical piece, the BASIC Stamp module running everything, two basic servo motors for opening the two doors, a low-voltage top mounted light to show everything in a dim yellowed tone (like an old machine might have), an IR sensor for the coin-op slot, and a very simple little motor or armature that just has to shove out a card one at a time, from a spring-mounted little box where the cards are loaded like a bullet magazine, so that as one is dispensed the weight loss makes the pile rise and 'loads' the next card.
Presuming I'm using all that for the total effect, but it's all for very brief or one-second operations, and that I'm not needing it to run constantly, can this be done on an independently-stored battery arrangement inside the back, or am I totally out of luck and I have to suffer having a twentieth-century power cable sticking out of a 19th-century-looking illusion?
Comments
My boebot ( BS2 and two servos ) can run a substantial amount of time on 4 AA batteries.
Your project should be feasable .. as far as power consumption is concerned.
The challenge will be the mechanics. I look forward to see some drawings and diagrams.
Good luck and keep us posted.
Ed
NiMH type batteries are also an option, smaller and lighter,·but are a bit more picky about how they're recharged.
You could go with non-rechargable batteries if the expense over time is not that important, but I think you will be replacing batteries fairly often.
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- Rick
My 2 cents
Marty
Second choice would be NiMh, they store 2x as much power a NiCds. Just don't fast charge them. I've never seen a fast charger that will charge them all the completely, just use a slow charger with maybe an extra set to trade out.
Alex
It is available in most RC Hobby store or any electronics store. also please obeserve when using this kind of battery. My robots are powered by a lithium polymer and a switching regulator to conserve power.... You may search ebay about 123a type of lithium...
-Phil
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Think Inside the box first and if that doesn't work..
Re-arrange what's inside the box then...
Think outside the BOX!
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My computer, http://forums.parallax.com/showthread.php?p=630466
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- Rick
This project is the kind that excites the heck out of me! You've gotten alot of good feedback on the power end of it but I too would love the see the mechanics or help on it. Also if you are going to use a Stamp and need help on the code-I'm in! I can see a neat Nuts & Volts or Servo magazine article on the horizion.
Keep us all posted.
Danny22
In response to the questions: I don't yet have a fixed diagram of the overall design, partly because I'm pretty much learning as I go not just in the robotics and programming but also in things like casting resin for the head, wire sculpting, painting, etc. I'm even learning the basics of classic wood varnishing and construction. I'll happily provide a better detail of the specs and such when I reach a closer point of operation design.
I am thinking that the concept of either an RC battery or basic lithium rechargeable setup is going to be the most feasible. The actual box itself doesn't have to move around at all, just the little diorama devices within it, so I realize that an AC cord would be technically doable, but this is something where I would like to go the extra mile so that I could literally walk in, carrying the thing in my arms, set it down, and it's already ready to go on its own.
The most I can conceive doing is charging up the batteries, putting them in for the day's operation, and then locking up the back to avoid any tampering, and leave it at that. Then I can unlock it later to recharge when I get it home.
I'm slowly teaching myself the basics of, well, BASIC programming. I almost could kick myself that just as I was beginning down this road the Propeller comes out and suggests that it might even be more versatile and flexible in running an operation like this with multiple, independent-but-coordinated events off of a single controller system.
But right now, I'm still trying to suss out things like programming for a continuous-rotation servo (I'm still learning with the standard servo that came with the deluxe kit) and how to coordinate sensor or output data like on an LED (I'd really like to see if I couldn't wire up an LED display so that I could also look in occasionally and see how many times the Tik-Tok Tarot has been run, if only for curiosity and bragging rights' sake). I will no doubt be asking more questions on things like the coding down the road.
But if so many of you think it's feasible to let it have its own indepenent power supply, then at least that assures me I'm not already going down the road of a fool's errand where that idea of the design is concerned. Even if it took a dozen D-cells, I'd rather arrange for that than to have an ungainly power cord sticking out of something that otherwise is already starting to shape up like a real turn-of-the-century-built device.
Now I just need to look into how to hook up a sufficient battery casing to hold the batteries and supply the resultant power to the array. Parallax here seems to only offer AC cord options, but I'm sure with some additional Googling around, I can find a compatible supplier of battery hook-ups.