Call for participation -- first draft

[nilcum]

Yes, I agree that there is a fine balance to be achieved with complexity, having realistic goals, and cost. Here is where I think we agree:

* Arduino based
* Vibrator control
* SOME level of flexibility

So, there are a few things I can think of to help address this. If we are going to produce a Arduino shield or provide instructions on how to modify / build your own it should have a modular way to attach toys. I think 3.5mm audio jacks are a good choice for this. Hook up any thing you want to it. I also think it would be good to have a relay control for toys that hook up to main power. Plug in anything.

For a mains relay it would be on/off only. For the 3.5mm jacks we should offer a variety of functions controlled at the microcontroller level. For example, if we can use PWM to drive the vibrator at low, medium, high, wave, slow pulse, fast pulse, and response to analog input we can do a LOT with that. We could also try to work out some sort of switch that could be inserted in a batter pack of a traditional toy.... haven't thought that one out too much but it could be attached to the same 3.5mm plug.

On the software side here is what I am thinking. We get some community feedback to pick one tease. We convert this tease to interface with hardware. The tease will only need img tags to http://127.0.0.1:8888/?vibe=low or something similar. I will write a web server that our users will run that will serve back an image (needs to be an image to get around the cross domain issues) and send the commands over serial to the arduino.

In terms of cost, it should be the cost of an arduino ($25 or so), a toy (bullets can be had for $5), and a few basic electronics to drive the DC motor (<$20). So, I think trying to keep our price point around $50 is a good goal.

What do you think?

[PiJoy]

Nilcum,

You wrote:

Yes, I agree that there is a fine balance to be achieved with complexity, having realistic goals, and cost. Here is where I think we agree:

* Arduino based
* Vibrator control
* SOME level of flexibility

I agree with those, and would add a couple more:

* Firmata for the PC <=> Arduino communication, until/unless we find something we need to do that firmata can't do. (And I think firmata is somewhat extensible, so it's probably fine as is.)

* Control motors with PWM for variable speed. (Not sure that we need direction, but direction control's unlikely to hurt.)

* Control at least two motors independently. (And I think we should get two variable speed motors working before adding more complexity.)

* Reserve at least two digital inputs and two analog inputs (agree on Arduino pins not to use for motors.)

One thing that looks like it'll be an issue is a high-current (at least 2 Amp, low voltage power supply), to run two vibes, both at max power at the same time. 2 Amp wallwarts are not common items. For those comfortable with electronics, a PC power supply is pretty easy to modify, and the +3.3 volts at oh-my-god current would be great for most battery operated toys. However, I get the impression that hacking an ATX power supply might scare too many people off, even though (to my mind) there are some pretty good tutorials out there, with pictures and everything. In the US, I can probably find a surplus supply that's not too expensive, but I don't know about what would work elsewhere. (One attractive thing about scavanging a PC's supply is that if one scavenges locally, the supply ought to work with local power, without a hitch.)


I like the idea of using 3.5 mm plugs for vibrators.
I'd like to suggest "reserving" 2.5 mm plugs for sensors, so the two types don't get mis-connected.

Enough for now. I think I'm getting off into TL;DR territory.

[Bandit224]

http://www.bgmicro.com/ sells 5V 3Amp wallwarts for about $5. 2 amp and 4 amp modules are also available.

[Nezhul]

If you need a tease written in nyx, I can help. Can do pretty advanced stuff. Although no time to help you with actual programming right now..

[nilcum]

Thanks for that link Bandit. I would personally like to see a power supply that could take 220v as well as 110. There are a lot of European users here. My powers supply here was reading about 300mA on for one of the eggs I have. Going up to 1 Amp per device might be a bit overkill, but I would rather have the power if we need it. Hacking a PC power supply is probably not something we want people to do. Not when with a little shopping you can solve the problem for $5. With that kind of current draw it's no wonder vibrators chew through batteries!

I would be on board with exploring firmeta. The little I've looked into it does make it seem very flexible. I a big on having the microcontroller be told a state fro the vibrator and having the controller handle it from there. The more complex routines like pulsing and wave would be fun to do but I could see firmeta getting in the way of that capability. Like I said, something to explore.

PiJoy sent me this link: http://www.adafruit.com/products/81 for a motor shield that will drive 4 DC motors with up to 0.6A each. The terminals here make it easy for people to hook up which every toy they like. The cost of this shield, plus a high current wall wort, bullet vibes, and arduino put us somewhere somewhere close to $70. Which is still good and it does balance complexity with flexibility nicely. It is probably overkill for what we need and the current might be limitation. Is it worth trying to do something cheaper and custom?

Thanks,
Nil

[nilcum]

Also, here is a 5v 3a power supply that will do 100V-240V. $7.99 http://www.ecrater.com/p/6060406/d-link ... ac-adapter

[Bandit224]

It is probably overkill for what we need and the current might be limitation. Is it worth trying to do something cheaper and custom?

It looks good. Making a custom servo motor won't save much money at all, but we could also try to adapt other servo motors into the machine as well. For instance, a geared dc motor for a custom-made sybian . Granted, a custom-made sybian alone will be way over our expected budget, but I consider it one of the "optional attachments" and not the main controller project that we're working on.

Cool link of just servo motors
http://www.hobbyengineering.com/SectionM.html

It would also be cool if we could incorporate the Penile Plethsymograph project into our controller (only with seraphox's permission of course), but I think it would only be the software end that would really need to do anything. The hardware side can just be considered "optional attachments."

[PiJoy]

<snip>

PiJoy sent me this link: http://www.adafruit.com/products/81 for a motor shield that will drive 4 DC motors with up to 0.6A each. The terminals here make it easy for people to hook up which every toy they like. The cost of this shield, plus a high current wall wort, bullet vibes, and arduino put us somewhere somewhere close to $70. Which is still good and it does balance complexity with flexibility nicely. It is probably overkill for what we need and the current might be limitation. Is it worth trying to do something cheaper and custom?

Thanks,
Nil

At this stage, I am against trying to design and fab a custom shield for Milonova Kinksters (Read that as, I'm not in any hurry to design and fab custom shields.) That would only make sense to me if we had a well-defined, standard set of vibrators, etc., and we were making huge numbers of them (100+.) Instead, lets start with something we can buy, adopt to our fiendish purposes, and then focus on the software needed to make it work with Flash teases.

(I'm also wondering about what software would be needed to control the vibes via chat or some sort of private messaging. The open-source chat software Pidgin http://sourceforge.net/projects/pidgin// might be a good basis for that -- but later, much later.)

If it turns out that there really is a sizable market, then we could reconsider making a custom shield. But for the early stage, where we have neither hardware of software defined, I favor the use of already-designed, easy to order modules, wherever we can. I have bought Arduino-related stuff from Adafruit, and had good luck. She ("Lady Ada") also puts up very detailed instructions.

Just to muddy the waters with more options,
There's at least two other Arduino motor shield that might be of use for participants who want more current than the adafruit motor shield (which maxes out at 0.6 Amps steady state.)
The first is from sparkfun.com (and I've had good luck with them on other items, and gotten lots of useful info from their instructions and forums.)
$25 US wIthout connectors, http://www.sparkfun.com/products/9815
Or $30 US with all the connectors included (probably a safer option, unless you have a well-stocked parts drawer), http://www.sparkfun.com/products/9896
Both of the above can drive only two motors, but they each can be 2 Amp steady state (and about twice that momentarily.)

Here's at least one more I've found, from a company I've never ordered from: "Freeduino motor shield" $11 US http://store.nkcelectronics.com/freedui ... d-kit.html
It's based on the TI SN754410NE motor driver. It appears this one can drive either one motor bi-directionally, or two motors one direction only. I'm a bit leery of this one, because it doesn't have external protection diodes, and the SN754410NE is supposed to have marginal internal protection from inductive loads (e.g. motors.) It claims to be compatible with the Arduino Duemilanove, and I'm not sure it's been tested with an Arduino Uno, which is probably the best short-term choice for Arduinos. (I'm very interested in the 32-bit Arduino, the Arduino Due, but that won't be out until the end of the year, at best.)

I suspect that the adafruit option is the safest, although lower in power. The Sparkfun one is higher current, but only two motors. The last one by nkcelectronics seems a bit risky, due to questionable robustness (no protection diodes) and no explicit statement that it fits the Arduino Uno. I suspect that a motivated user, with a bit of Arduino and electronics could make any of the above work (or build a custom circuit.) However, the adafruit one, with screw terminals, is IMHO the most friendly to new-to-electronics kinksters.

I'm hoping we can come to a consensus on a motor shield to adopt, instead of trying to support every motor shield on the market. My first choice is the adafruit shield, with the sparkfun one second choice (for those with high-current toys.)

Please chime in with your opinions!

[Bandit224]

My first choice is also the Adafruit shield. The safety features, like the pull down resistors, are extremely important, and we know it supports the Adafruit Uno and other Adafruits. If we need more Amps, we can always go custom, or try something else.

[PiJoy]

Earlier in this topic, I wrote:

(I'm also wondering about what software would be needed to control the vibes via chat or some sort of private messaging. The open-source chat software Pidgin http://sourceforge.net/projects/pidgin// might be a good basis for that -- but later, much later.)

I'd like to correct myself, the chat-enabling software I was thinking of is called Jabber, http://www.jabber.org/
and http://jabber.sourceforge.net/ Among the good things about jabber is that it's open source, so a variant could be coded, that watched for certain kinds of records, and relayed them to our hardware as commands. Jabber is also distributed, and one can apparently get accounts on various servers for free. (So setting up our own isn't absolutely required.) Here's the short description from the jabber.org webpage:

Jabber.org is the original IM service based on XMPP, the open standard for instant messaging, and one of the biggest nodes on the open XMPP network. Create an account by visiting register.jabber.org or one of the other public XMPP services, then download a free client, log in, and start chatting!

[Nezhul]

Well if it comes to that then you can actually use any messenger protocol, be it jabber or even ICQ. Al you have to do is simply write your own client that will recognize certain words as tags and generate hardware commands for your device through a simple driver.

[PiJoy]

Greetings all,

I just received some new toys, and measured their max current, with fresh batteries. This gives us some data on currents needed for some representative vibes. If any of you have a vibrating toy and a meter that reads DC current, please measure your toys with fresh batteries and post your results also.

1:
Small pager motor (vibrating cock ring), with two fresh AG3/LR41 1.5 volt alkaline button cells: 25 mA

(I seem to recall running larger pager motors (about 2x as long) at 90 mA, but not constantly on, maybe 50 -- 75% duty cycle.)

2:
"Water Sealed Silver bullet" vibe, mgfr=D.A.V.E., with two fresh AA alkaline cells: 250 -- 300 mA (slightly higher when the vibe is held firmly; lower when allowed to hang free.)

3:"Rump Shakers" vibrating butt plug, mfgr: Doc Johnson: 650 -- 700 mA (higher current when held firmly, making the motor work a bit harder.)

The measurements above indicate that the http://www.ladyada.net/make/mshield/ (whose H-bridge drivers are rated 600 mA) can almost (but not quite) handle the biggest current draw of the toys I measured currents on. 600/700 = 85%, which is pretty close to full power. The above measurements do however suggest that some toys cannot be run at full nominal current by the 600 mA bridge drivers on the ladyada shield. So either current-limiting resistors or careful limiting of the PWM for such high-current toys will probably be needed. The driver chips have thermal protection, so they shouldn't fry, but having a thermal shutdown of a toy during play would be a let down, to say the least!

If any of you have battery-operated vibes -- especially powerful ones -- (and a meter), please measure your toy's max current and post here. The more info we gather about the electrical needs of vibes and related toys, the better we can pick appropriate hardware and make progress on flash-controlled hardware for fun and perversion.

Thanks!

PS Splicing an Ammeter into the circuit may take some engenuity and/or some electrical tape, to make the measurement without cutting any wires. I used a (separate) battery pack for AA cells, and some clip leads in place of the power packs for my two AA cell-using toys. For the little button cells, I carefully taped two in series with wires taped tightly to each end of the stack. Yay electrical tape, right up there with duct tape!

[SexualChoc]

Awesome,
No way to go to larger batteries is there?
I like using rechargeable
I understand small best for portability,
just curious.

[PiJoy]

Awesome,
No way to go to larger batteries is there?
I like using rechargeable
I understand small best for portability,
just curious.

My measurements were just a few data points for us to start with, nothing definitive.
One could certainly go to larger batteries; however all these motors have a maximum power dissipation, though we don't know what that is for these motors. I suspect that most of these could be run for an hour, at somewhat more than what I measured. However, without a motor part number, I don't know how to find the limit, except for raising the current, running it for (you pick how long), rinse and repeat until the motor fries, or you decide to stop.

Some re-chargable batteries don't do well at heavy current draw, which vibrators are, IMHO. However, I'm no re-chargable battery guru. I suspect that LiPo batteries are better at heavy current draw, but from what I've read, one must be *very* careful about charging them (and neither charging too fast or over-charging.)

@SC: If you know about re-chargable batteries, please summarize and/or post relevant links.

Thanks,

[Nezhul]

As I know rechargable battaries come in a few basic shapes, and actually mimic the measurements of normal battaries of the same standart. i.e. rechargable AA accumulator would give out the same voltage as normal AA battarie. The difference is only in chemicals inside, but that's irrelevant for you, I think.
Also you can always use 15 volt AC-DC power block. It's plugged in a normal 220v AC power source and it's output is 15v DC. They are small and handy.