www.BoundAnna.com

http://www.spankermachine.com/

I have one and I like it. It really needs a better timing device.

Interesting

I bought one of those, and it's pretty good. It's very WYSIWIG, there are no fancy timing or pattern options, just power and speed, but it works. For the price it's a fair deal.
If anyone in the UK wants one, I will probably sell mine since I plan to upgrade soon.

Oh, and one thing I would recommend: the spanker machine does not come with a floor stand, so you will need to put together some kind of rig or stand for it. Don't underestimate the importance of a good adjustable stand.

I received my new spankermachine today. I already had the old model, but the new one is stronger.
It works pretty well with short canes, a wooden spoon or a ruler.
It doesn't feel like 30% stronger like they're claiming, but it's enough to have a reminder tomorrow

I had the old machine connected to a RaspberryPi to have more timing options and I'm currently experimenting with an IoT board, so it can be directly accessed over Wifi.
I'm going to post some plans in the DIY section on the weekend...

I think it's a very interesting thing to try. But too expensive unfortunately.

It isn't that expensive actually (104€). A very basic device, but quite good for that price

Welcome to Bound Anna, John

I've been idly wondering whether anyone's tried using a robot arm for spanking. Not the full industrial setup but the education/maker/hobbyist devices that start from £100/€100/$100 for four or five axes of movement. They'd certainly have the flexibility to be able to vary the point of impact and maybe with suitable programming to work over buttocks and thighs separately and perhaps even change whip during the session, but do they have the acceleration and strength to cause pain with even a basic bamboo cane or nylon riding crop? Maybe I need to put a Nema 17 or 27 motor and controller or two on my next order from China to do some testing?

Sergio wrote:... but do they have the acceleration and strength to cause pain with even a basic bamboo cane or nylon riding crop? ...

Without having tested it, I guess that that is EXACTLY where things won't work as supposed.
The strength shouldn't actually be the problem.
However, the acceleration needed is certainly a factor. Even more so, the sturdiness of the arm is at test here. After all it has to withstand the impact of the cane (or whatever you intend to use) on it's target, too.
Plus, depending on the arm's angle upon contact, the resulting torque and thus the impact on the arm's mechanical components will be even bigger than the impact on your body.

All in all it seems, that a good lot of tinkering will be necessary to make this work.

Then again, none of the problems I mentioned are unsolvable:

- The arm yould be used to vary the position of a spanker, that would otherwise hit the same target repeatedly, instead of using the arm as a spanker
- The spanking mechanism could be designed to act like, e.g., clay target throwers. It's actually a very common way to construct spanking machines, iirc.
- If you use a whip instead of a cane, the arm should at least be protected from impacts being thrown back into it. It will require a bit of tinkering, to create enough acceleration, though.

I'm not sure, whether this helps, but I sincerely hope it does!

Kind regards and good luck

Blacky

Sergio wrote:I've been idly wondering whether anyone's tried using a robot arm for spanking. Not the full industrial setup but the education/maker/hobbyist devices that start from £100/€100/$100 for four or five axes of movement. They'd certainly have the flexibility to be able to vary the point of impact and maybe with suitable programming to work over buttocks and thighs separately and perhaps even change whip during the session, but do they have the acceleration and strength to cause pain with even a basic bamboo cane or nylon riding crop? Maybe I need to put a Nema 17 or 27 motor and controller or two on my next order from China to do some testing?

Speaking as an engineer I doubt the average hobby robot arm is going to be able to deliver any kind of forceful blow, they usually use quite small motors with lots of gearing to compensate for the lack of torque and high RPM from the motor.I've recently seen a direct drive design, but that arm was still relatively small and made of plastic. Not something I would expect to cope with the stresses.

If you want to go down this route it's quite easy to get a good idea for the general specs you'll need if you just look at the torque required by making some estimations. Let's say the intended hitting implement is a cane weighing some 50 grams. A human will make a roughly 180 degree swing in approximately 0.05 seconds. Assuming a constant acceleration Alpha = Omega/time = (Pi*(finalRPM))/(time*30) -> our angular acceleration would be aprox. 21 rad/sec^2. Lets assume our cane is a homogeneous rod of uniform thickness, with a length of 40 cm, rotating about it's very end, the rotational moment of inertia I=1/3(m/(L^2)) -> 0.1042 kg*m^2. Thus, required torque is 21*0.1042=2.18 Nm. (Keep in mind, that's just the cane itself, for what is likely a light swat, it ignores any additional weight of the arm itself.) The trouble with direct drive electrical systems like this is that they don't really like the "explosive" short pulsing power required for this application. Certainly good cooling and high power drive electronics would be required, beyond the normal hobby grade stuff. The problem is that you need to deliver all that power from basically standstill where you're power curve, current curve and efficiency curve are all working against you in a very, very short pulse, without the luxury of a lot of acceleration time. Motor windings tend not to like that sort of high current low RPM application.

I do think it should be possible to build a "direct drive" spanker machine that uses a rotational voice coil or a BLDC motor without all that tedious mucking about with springs and the like. That's on my "one day, when I have a proper metal hobby shop" list, but not for right now as 3d printed plastics certainly aren't going to cut it.

Before I got involved with the face-to-face kink world, I did some experiments with electric motors.

I had a 12volt dc motor, it was designed for low rpm but high torque, IIRC pulled about 10 amps on 12volts but I ran it on 24v so probably over 300 watts. It was switched from a rest position with a power MOSFET and switched off at about 180 degrees rotation, with (cane) contact occurring at about 200 degrees. It then returned to base at a slow speed. I used Hall Effect sensors for the limit switching, plus a microprocessor to givea random number of strokes, at random intervals, and an electronic release for cuffs etc (and, of course, a mechanical timer) Just for fun (?) there was a buzzer that beeped just before the cane operated.

From subsequent experience with a number of accomplished Dommes (including my wife!) I would say my machine was 4 on a scale of 10. One problem was that the target was fixed by the position of the machine, so if I didn't, or couldn't move, each stroke hit the same place. And the blows were always the same strength. With a Domme holding the cane, the number, position and strength of strokes depends upon her evil nature, plus there is the verbal interaction (well, perhaps one-way...) Then there is the decision to end, or not end the session, the change of implements from the sting of the dressage whip through to the thud of a thick Delrin cane. And I limited the number of strokes on the machine to, IIRC 32, but the "real" sessions usually included far more - I did have a session with a Domme who wanted to show me the range of implements she had, with 20 strokes from each. She had 20 canes...

I know a thing or two in this area, having tested many different approaches

The Spank-O-Matic, operated with 150 PSI incoming air, propels the implement with 250 pounds of force over about 90 degrees/3" in standard config. The XP doubles that. This design is built to operate everything from a cane to a paddle weighing several pounds... a caning-specific machine would be better with a smaller diameter cylinder.

https://orgasmalley.com/product-categor ... -machines/

OrgasmAlley wrote:I know a thing or two in this area, having tested many different approaches

The Spank-O-Matic, operated with 150 PSI incoming air, propels the implement with 250 pounds of force over about 90 degrees/3" in standard config. The XP doubles that. This design is built to operate everything from a cane to a paddle weighing several pounds... a caning-specific machine would be better with a smaller diameter cylinder.

https://orgasmalley.com/product-categor ... -machines/

I like the simplicity of the pneumatic system you've designed, but I'm a little wary of the amount of "extra" stuff you need to power it, and I've never seen an air compressor capable of any sort of volume output that didn't make a massive amount of noise when running, which would rather turn me off.

Ps: out of curiosity do you use a special type of pneumatic actuator? Most I've seen give a pretty low max speed rating and seem to have quite a lot of resistance.

Compressors come in quite a range, from dead silent to quite loud. The standard head does well with about 1CFM minimum, a throughput that has a number of options. Personally, when out of the range of my piped compressed air at the shop, I use this: https://www.senco.com/tools/details-page/pc1010 At 68dB it's a bit less noise than a hair dryer when running. Very compact and easy to carry and store. That's occasionally bothersome, and I've used a passive air tank which is silent but must be pressurized from an external source. My 10 gallon tank is good for more than 400 moderate (70 PSI) strokes before pressure drops below that level. I have customers who use a CO2 tank with appropriate regualtor... that's handy because they're pressurized to the 2000 PSI range and even quite a small tank will last many sessions. Other people use a large compressor and employ it like a passive tank... fill it beforehand and don't run it during a session. Of course, whatever the air source you can move it away from the session to a basically unlimited distance with more hose.

A bigger compressor issue is that most compressors have a turn-off pressure lower than the SOM system's 150 PSI limit. At 100 PSI with the Lexan paddle (3/8" thick, 3" wide) the standard head is not quite as powerful as an average adult man, and those looking for more power look for a higher pressure compressor... which are out there, but tend to NOT be the quietest ones.

You may be thinking of some other sort of actuator. I've never seen a speed rating for a pneumatic cylinder... the only limitations are the port sizes, incoming and outgoing. As fast as you can get pressure in, it will push the piston forward. There also isn't any inherent resistance to movement in a pneumatic cylinder. It's simply a guided shaft with a piston in it that runs within a bore. You can create resistance in either direction by adding a spring or restricting the flow of air from the unpressurized side of the piston. I use a single-acting (pressure connection behind the piston, relief hole forward of the piston) cylinder with an internal return spring, and add additional return force with an external spring.

OrgasmAlley wrote:You may be thinking of some other sort of actuator. I've never seen a speed rating for a pneumatic cylinder... the only limitations are the port sizes, incoming and outgoing. As fast as you can get pressure in, it will push the piston forward. There also isn't any inherent resistance to movement in a pneumatic cylinder. It's simply a guided shaft with a piston in it that runs within a bore. You can create resistance in either direction by adding a spring or restricting the flow of air from the unpressurized side of the piston. I use a single-acting (pressure connection behind the piston, relief hole forward of the piston) cylinder with an internal return spring, and add additional return force with an external spring.

Example:SMC C85 ISO cylinder See page 3, speed rating 50-1500 mm/s, and maximum kinetic energy ratings if using the cylinder end-of-stroke bumper (either air cushion or rubber bumper) which doesn't really apply if you have an external end-stop. I'm guessing the speed rating will have to do with seal wear, but I doubt your spanker machines will reach the millions of strokes required for that to become problematic. I keep forgetting not everything is an industrial design that has to have a mean time before failure of at last 10 years and/or 12 million cycles

As for resistance, I confess it's been a while since I've handled anything pneumatic, and my comparison might be a bit skewed as my day job often involves electromagnetic drive linear actuators on high precision air bearings or ball-return guides, which have basically no resistance whatsoever. Especially new air cylinders in my recollection have quite a bit of seal friction (both on the piston to cylinder bore and the rod in the rod gland). Nothing too showstopping if you're blowing 150 PSI into a 1 inch cylinder I guess