estim project

Sometimes you just have to do things yourself.
justDIY
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RE: estim project

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I've been working on a modular e-stim system the past few months. It's still a long way from completion, but it is starting to gain some function. Here's a screencap of the windows control / programming interface.

The estim itself is self contained, battery powered, and can be connected to the PC over bluetooth or usb. I've made a lot of improvements to my high-voltage circuitry and driver, this stim unit delivers very impressive continuous power from only four AA batteries. Improvements to the driver and programming now allow for 1000 intensity "steps", a big improvement over my previous prototype that only allowed for 50 steps.

So far I've programmed four simple functions:

Ramp; power increases and decreases based on the intensity set point, speed of the ramp is adjustable with the step setting.
Ramp up; power increases on a ramp and then drops to zero
Ramp down; power comes on at the full set intensity and ramps down
Pulse; power alternates between full set intensity and off

All of these functions are governed by an on time and off time delay, which other devices call the "frequency".

Yet to do:
Finish the channel link option, which lets me control multiple outputs with one set of inputs.

Add the ability to record, edit and playback sessions.

Add the channel-wait feature, which will trigger a channel based on the status of another channel, like channels alternating, or have a second set of trodes come alive when a channel reaches a certain level.

Add the ability to personalize channels, such as set a max power, time (frequency) limits, whatever else I can think of, and more advanced options like change the AC current frequency (currently fixed at 500hz)


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JCRubberAndRope
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RE: estim project

Unread post by JCRubberAndRope »

Hi justDIY, did you build the estim itself or is it a bought system that you have modified?

justDIY
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RE: estim project

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I built the unit myself.  It's a modular design, consisting of a control chip on a master board which talks to the computer and a number of slave boards which perform various functions.  so far the function i've been working on is the estim boards.    I also plan to implement boards to control things like vibes, mag locks / key releases, etc.Each estim board has two output channels, so four (or six) electrodes.  The estim board has a small processor chip that controls an h-bridge chip, which drives two small audio transformers.  battery voltage enters the h-bridge chip and has is turned into a high frequency alternating current, which is then amplifed by the transformers.  The audio transformers have a center tap, which can be used to split the output of a channel across three electrodes, or the full output power can be used across two electrodes. 

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JCRubberAndRope
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RE: estim project

Unread post by JCRubberAndRope »

Cheers, sounds a great project.

justDIY
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RE: estim project

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Progress is being made, slowly but surely. I've made more screens on the windows side, as well as doing some development on the electronics side. Here's a pic of one of my modular estim units, rigged up for stand-alone operation as an SB torment device.



What you see here are two small step-up transformers, a quad half h-bridge chip and a microcontroller. The green terminal blocks provide input power, currently 4 AA batteries (5-6 volts DC), and output power to the electrodes. The white terminals provide connection back to the master control board, when operating in slave mode, or to be reprogrammed. The black thing wrapped in electrical tape is a simple voltage regulator to allow the board to operate disconnected from the master.

The microcontroller performs three basic roles (these are simplified):

1. Generate a signal that causes the h-bridge chip to switch polarity rapidly, generating an AC current in the transformers.
2. Generate a second and third signal that enables / disables the two outputs of the h-bridge chip, energizing the transformers. This signal varies from very short pulses to much longer pulses, called pulse-width modulation. Relying on the inductance of the transformer to average out the current, these pulses allow the module to generate more than 1000 intensity settings from barely a tickle to holy-shit.
3. Implement timers controlling the frequency (duration) of the two channels.

More to come!

justDIY
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RE: estim project

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I took the device out for a "field test" today and it worked great. I used a bi-polar anal insert with a strict crotch rope to keep it in place. The device was programmed for controlled random operation, with on times of 1 sec to 30 sec and off times of 2 sec to 30 sec. Intensity was set to random chose between 20 and 120, which is about 2% to about 12%.

I was able to walk my dog, and visit three different stores to do some shopping, while being shocked very frequently by the device.

For a repeated field test, I'm going to extend the off time to chose values between 20 and 60 seconds, as estim delivered too frequently tends to lose its "punch". After the first 30 min or so I was accustomed even though the power level was random. It felt more like a vibe turning on and off then shocks.

After about 90 min of continuous operation, the batteries show minimal drain, so they should be good for much longer sessions. I'm using high current nickle metal hydride batteries designed for a DSLR camera, so this application is like a yawn to them.

Ashleigh
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RE: estim project

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Hi justDIY,

Any chance you could post your schematic? How do you program that board (what is the ICSP connector for, USB?) Once programmed, can it be unhooked and act on its own? The board looks pre-etched, can it be bought somewhere?

I'd love to try something like this out.

justDIY
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RE: estim project

Unread post by justDIY »

[quote="Ashleigh"] Hi justDIY,

Any chance you could post your schematic? How do you program that board (what is the ICSP connector for, USB?) Once programmed, can it be unhooked and act on its own? The board looks pre-etched, can it be bought somewhere?

I'd love to try something like this out. [/quote]

I might post it after more testing, the design is really straight forward (crude) hardware wise

The ICSP connector is for programming the firmware on the microcontroller, the eStim routine is programmed through the white connectors (either one), but only by a master control board.

Right now only a set of randomizing parameters can be uploaded to the individual boards for stand-alone operation, they don't have enough memory to hold any kind of routine. The master controller however has a ton of memory and will eventually control and sequence multiple eStim modules, along with vibrator modules and key release modules - all the brains of a self-bondage robot of sorts.

The circuit board has been professionally fabricated by a prototyping service, created from my design. They are not for sale anywhere ... maybe I will eventually license my ideas to Erostek or someone else.   

I need to have another run of boards made as I've changed the wiring from the initial design used to create the boards. The top looks nice but the bottom is a mess of wires running everywhere.

justDIY
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RE: estim project

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I received a resupply of parts from my vendor and I was able to assemble two more estim boards today, a matched pair. These will be dedicated slave boards to the master controller. I also tried a brief session with all four channels, and it was sensory overload on my nether regions :)

one deep anal 'trode as a "common", one resting in the anus, one on the balls, one on the base of the cock, one around the glans (head), and one urethral probe. yes that's only six ... some of the outputs were stacked on the deep anal 'trode as a common. the isolation of the channels allows them to operate without shorting each other out.



a pic of the two boards connected together, and to the controller. each board is using its own set of batteries not because they need that much power, but because I didn't feel like daisy chaining a power cord



I've found a next square of plywood to mount my devices on, will eventually make a plexiglas box for them, but for now this'll do. the two assembled boards are on the left, with two unassembled on the right. an unassembled controller sits at the top, next to a battery pack.

I don't think I'll need four more stim channels, there are boards in the works for vibe control, and mag-lock control.

justDIY
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RE: estim project

Unread post by justDIY »

Progress is on-going, mostly software work, nothing much new on the hardware.

I have given a lot of thought to sharing designs, schematics, even boards:

I will share almost every aspect of this project with everyone, with the exception of the eStim boards. I will not share any aspects of the eStim design, other than the general information I've already provided. Here's why...

From my research and knowledge of the legal world, powerful estim units are expensive for two reasons.

#1 Expensive Insurance; Liability insurance to cover the "what-ifs" of someone foolishly injuring or killing themselves with a device make an insurance adjuster see dollar signs. Sure, they put disclaimers, waivers, warnings and other boiler-plate on the device and in the instruction manual, but none of that will stop someone's family from hiring an ambulance chaser and suing the company. The boiler-plate will probably protect them from a judgement in the end, but it won't cover their legal costs to mount the defense.

#2 Limited market; The things just don't sell like hotcakes, so they're probably hand-made, and that is really expensive.

Since I can neither financially afford that kind of insurance, nor would I want to mess with a lawsuit, I will not share my eStim designs. I do not think they are dangerous, especially powered by only AA batteries, but I cannot control what someone else might do with my designs.

So, with that out of the way, here is what's new:

I've completed designs on a few more boards, these are just renderings of the PCB, the real deal is out for manufacturing and should be here in a month or so.



1. DC Output Module. This module can directly control two battery powered vibrators or two electromagnetic locks, or any other DC device up to 12 volts dc. Using a gizmo called a powerswitch tail, this module can safely turn on/off AC line powered devices. The module has two constant-current drivers to protect the motor of a vibrator from running too hot, while also providing smooth speed control - much smoother than the crappy adjustment most vibes come with. It also has a USB port for programming and operation separately from the master control module.



2. Analog Input Module. This module provides nine low-voltage analog inputs for use with the master control module. This allows for expansion of the controller to respond either to the sub, the dom or the environment. You can either connect knobs / sliders to have that old-school control feel, or sensors like photo-cells, pressure switches, even use with conductive rubber cock-rings to measure just how hard you are.



3. Four Digit Display Module. This module provides the master control module with an output, other than blinking lights or the computer screen. Use it to display time remaining on a mag-lock countdown or the power level of a vibrator in a special place.

All these modules are "modular", and the controller will detect and support multiples of each, along with the estim module that started this thread.
justDIY2011-11-16 11:56:42

justDIY
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RE: estim project

Unread post by justDIY »

Here's a shot of the program editor... this program is simple, all the steps are for one channel on one module.



the programs can be up to 63 steps, and can control multiple modules, such as estim, vibe, maglock, or special functions like delay and loop.

for estim and vibe, the first box following the channel is the intensity, followed by the on and off time (frequency) in 0.01 second increments (100 = 1 second). The next field is the function, either a pulse which is just on/off, there's also ramp which slowly increases and decreases the intensity. There's also some randomizer modes in there that deal with time and power levels. The field following that is how slow the ramp is, with 1 being fastest and 99 being slowest, in 0.01 second delays. So for the ramp to go from 0 to 100 with speed set to 10 would take 10 seconds. The last box is the number of repetitions each line is active for.

The last line, #17, is a loop command, which skips back to step 13 and repeats four times.

Scotty
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RE: estim project

Unread post by Scotty »

that looks amazing.  let us know if they become commericially available
i like my bondage like sara lee pastry - layer upon layer :)

twistersam
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Re: estim project

Unread post by twistersam »

if you make them commercial available just sell them as DIY sets. The assembly can be done by the buyer, making the modules less exprensive.

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