Re: Vacuum bed self bondage
Posted: 24 Jan 2015, 21:06
Vac beds are definitely a unique experience; though I've never tried the expensive latex ones (US$ 350-500). I don't think you can expect people to avoid them because someone had a fatal accident with one. The best approach is to make them very safe which really is not that difficult nor expensive.
I tried to make a sealed vac bed, and I couldn't do it; there were too many little leaks, and the one-way valve picked up crud from using the vac to clean up the den when it wasn't connected to the bed. Therefore, if the power goes out, the vac stops and the vac bed releases. Or, if the shop vac fails, burns out, whatever, it fails in a safe way.
There's explosive bolts which might be available as surplus from the terminated US Space Shuttle program to release a sealed vac bed, but since I don't have experience with these, I don't recommend them
Even better, is to make not only vac beds but all SB safer with fail-safe interlocks. Many years ago I took a three day course with OSHA, which is one of the rare positive things to emerge from the government. OSHA means Occupational Safety and Health Administration (their motto: if you think OSHA is a town in Iowa, you're in big trouble). I had to manage a few buildings where physics experiments were being done, and OSHA could shut down anything that wasn't run with safety as first priority.
"Fail-safe" means that if the power goes off, or a wire breaks, or anything refuses to work, the system shuts down; design the system so that the only way it can keep going, is if all the fail-safes are functioning and reporting 'good to go'. Personally I don't think that electronic timers are necessarily safe; someone might program, for instance, thee days instead of three hours, and I don't know if they are immune to picking up glitches. But, you can always put two timers or more in series with the safety system, one digital and the other mechanical. The earliest fail-safe systems included the 'dead man switch', a pedal that a locomotive engineer had to keep holding down while running a train; elevator ('lift') brakes that would immediately engage if the cables broke, slowly lowering it to the ground floor; and train brakes that normally were fully engaged preventing any movement — a pressurized line released the brakes, but if anything came loose anywhere, the pressure would drop and the brakes would engage. Generally, several things had to be kept active and energized, or everything would shut down.
Actually, any sort of SB (rope, cuffs, etc.) can be made fail-safe, or at least more fail-safe, by incorporating a magnetic lock or electromagnetic latching device that must stay energized; if the safety system disables it, the SB is ended. A lot of people like ice as a release method, but if there's a fire, that might make the ice melt faster, but possibly not fast enough.
A typical fail-safe system has several safeties in series, like links in a chain; if any one of them goes down, the session is ended, liftoff is aborted, or whatever. Generally it's easiest, safest, and cheapest to do this with a few simple electronic circuits. I'd imagine that this could be sold as a fish tank monitoring system or anything similar that is easily pervertible for SB use. For instance:
--- One safety could be a cheap microphone as an input to an op amp; any sustained loud noise from a fire, smoke, or burglar alarm, motion detector, etc. shuts the safety system down;
--- Someone elsewhere mentioned hypothermia; if the core body temperature sensor (or fish tank water temperature) goes too low, the safety system goes down;
--- Likewise, if that temperature goes too high, the system goes down, an alarm sounds, and the fish is released from the tank so it can open a window and get a cool drink from the fridge. (Wait, ignore the thing about the fish);
--- pulse rate monitors have been around for decades. Forget the digital display. an analog output from a monitor can be turned into a stream of pulses, and that can be an input to an op amp integrator. If the integrator output is either too high or too low, the safety system shuts down; and finally,
--- For an emergency release, a microphone near the face goes into a differentiator that senses any rapid and sharp series of noises (e.g. Mf-Mf-Mf-Mf-Mf, or glug-glug-glug-glug, etc.) and then into an integrator circuit that will shut it all down.
Now, regarding the emergency release thing, people have suggested orange paint and urine on ice for a deterrent from using it. Well, I dunno, that sounds like more of an annoyance. Maybe a big annoyance, but there might be something more emotionally edgy that could add a sustained piquancy and drama to the scene. I've never owned and operated one, nor even seen one, but I've heard that there are butt shockers on the market that deliver a range of outputs, even to the point of being unpleasantly punishing and well worth avoiding, and it might take a few memorable minutes to remove. If the emergency release is used, then this thing would kick in.
---
nothing can be made fool-proof because fools are so ingenious.
I tried to make a sealed vac bed, and I couldn't do it; there were too many little leaks, and the one-way valve picked up crud from using the vac to clean up the den when it wasn't connected to the bed. Therefore, if the power goes out, the vac stops and the vac bed releases. Or, if the shop vac fails, burns out, whatever, it fails in a safe way.
There's explosive bolts which might be available as surplus from the terminated US Space Shuttle program to release a sealed vac bed, but since I don't have experience with these, I don't recommend them
Even better, is to make not only vac beds but all SB safer with fail-safe interlocks. Many years ago I took a three day course with OSHA, which is one of the rare positive things to emerge from the government. OSHA means Occupational Safety and Health Administration (their motto: if you think OSHA is a town in Iowa, you're in big trouble). I had to manage a few buildings where physics experiments were being done, and OSHA could shut down anything that wasn't run with safety as first priority.
"Fail-safe" means that if the power goes off, or a wire breaks, or anything refuses to work, the system shuts down; design the system so that the only way it can keep going, is if all the fail-safes are functioning and reporting 'good to go'. Personally I don't think that electronic timers are necessarily safe; someone might program, for instance, thee days instead of three hours, and I don't know if they are immune to picking up glitches. But, you can always put two timers or more in series with the safety system, one digital and the other mechanical. The earliest fail-safe systems included the 'dead man switch', a pedal that a locomotive engineer had to keep holding down while running a train; elevator ('lift') brakes that would immediately engage if the cables broke, slowly lowering it to the ground floor; and train brakes that normally were fully engaged preventing any movement — a pressurized line released the brakes, but if anything came loose anywhere, the pressure would drop and the brakes would engage. Generally, several things had to be kept active and energized, or everything would shut down.
Actually, any sort of SB (rope, cuffs, etc.) can be made fail-safe, or at least more fail-safe, by incorporating a magnetic lock or electromagnetic latching device that must stay energized; if the safety system disables it, the SB is ended. A lot of people like ice as a release method, but if there's a fire, that might make the ice melt faster, but possibly not fast enough.
A typical fail-safe system has several safeties in series, like links in a chain; if any one of them goes down, the session is ended, liftoff is aborted, or whatever. Generally it's easiest, safest, and cheapest to do this with a few simple electronic circuits. I'd imagine that this could be sold as a fish tank monitoring system or anything similar that is easily pervertible for SB use. For instance:
--- One safety could be a cheap microphone as an input to an op amp; any sustained loud noise from a fire, smoke, or burglar alarm, motion detector, etc. shuts the safety system down;
--- Someone elsewhere mentioned hypothermia; if the core body temperature sensor (or fish tank water temperature) goes too low, the safety system goes down;
--- Likewise, if that temperature goes too high, the system goes down, an alarm sounds, and the fish is released from the tank so it can open a window and get a cool drink from the fridge. (Wait, ignore the thing about the fish);
--- pulse rate monitors have been around for decades. Forget the digital display. an analog output from a monitor can be turned into a stream of pulses, and that can be an input to an op amp integrator. If the integrator output is either too high or too low, the safety system shuts down; and finally,
--- For an emergency release, a microphone near the face goes into a differentiator that senses any rapid and sharp series of noises (e.g. Mf-Mf-Mf-Mf-Mf, or glug-glug-glug-glug, etc.) and then into an integrator circuit that will shut it all down.
Now, regarding the emergency release thing, people have suggested orange paint and urine on ice for a deterrent from using it. Well, I dunno, that sounds like more of an annoyance. Maybe a big annoyance, but there might be something more emotionally edgy that could add a sustained piquancy and drama to the scene. I've never owned and operated one, nor even seen one, but I've heard that there are butt shockers on the market that deliver a range of outputs, even to the point of being unpleasantly punishing and well worth avoiding, and it might take a few memorable minutes to remove. If the emergency release is used, then this thing would kick in.
---
nothing can be made fool-proof because fools are so ingenious.