Mach Effect progress

djolds1 · Post by **djolds1** » Sun Dec 16, 2012 11:59 am

GIThruster wrote:I'm lost. Did this sanman from NSF perform an experiment based on Nembo's work?

Commented on and analyzed Nembo's SPESIF 2011 paper.

djolds1 · Post by **djolds1** » Sun Dec 16, 2012 5:48 pm

GIThruster wrote:I'm lost. Did this sanman from NSF perform an experiment based on Nembo's work?

Upon review, I found that this paper was posted to the NSF thread about a year ago - at the top of page 107. It looks like Nembo's SPESIF 2011 paper was never picked up on for discussion, as other matters of substance rapidly intruded. However, I only scrolled though page 108 to check.

OTOH, I do recall previous discussion of using alternate means (resonance chambers?) to generate Mach Effects somewhere.

GIThruster · Post by **GIThruster** » Sun Dec 16, 2012 10:41 pm

I don't recall use of resonance chambers. I recall the rotator experiment which was a rousing success, and the Mach Guitar experiment at UW which was incomplete and inconclusive.

djolds1 · Post by **djolds1** » Mon Dec 17, 2012 3:19 am

GIThruster wrote:I don't recall use of resonance chambers. I recall the rotator experiment which was a rousing success, and the Mach Guitar experiment at UW which was incomplete and inconclusive.

I hadn't read Nembo's paper when I posted this, and was inferring (badly) from the NSF thread. The proposed embodiment is essentially a modified coilgun.

GIThruster · Post by **GIThruster** » Mon Dec 17, 2012 4:07 am

Yes, while I do hope he'll pursue it, I have to admit I htink the things that should be top of the agenda are to:

a) generate more thrust
b) demonstrate more control, such that the thrust can be generated constantly as well as reversed and negated on command
c) replicated cheaply.

The problem with proof of science experiments like the rotator is no one cares about them. To get a real reaction from others there needs to be these three things above. The trouble with this is, that one needs all the test apparatus--the balance, the vacuum, the sensitive instrumentation, etc. Even if one finds a way to build a very cheap thruster and power system (which I have) one still needs to be able to measure these thrusts reliably. It's the simple things, meaning the balance and vacuum; that makes these experiments very difficult for the average engineer to do.

CaptainBeowulf · Post by **CaptainBeowulf** » Mon Dec 17, 2012 7:29 am

I don't know if (a) and (b) are compatible with (c). It seems like there's been a constant struggle to find parts/materials and construct the stacks so that everything is "just so." To demonstrate more thrust and control, most likely dedicated parts, manufactured to order, are going to be needed.

Your own cheap thruster might be a solution to all this, is there any possibility of having it tested in a lab with the proper equipment (vacuum chamber, balance etc.) and people who know what they're doing?

GIThruster · Post by **GIThruster** » Mon Dec 17, 2012 8:28 am

There are a handful of labs around the world that could do replication work fairly cheaply. George Hathaway up in Canada could do it. EarthTech could do it. Sonny White's Eagleworks lab could do it. These are all pretty heavily invested in ZPF however, and some have a personal stake to see the work fail. I would not want to use any of these labs for that reason.

Marshall Space Flight Center opened a new $40 M advanced propulsion research center run by Glenn "Tony" Robertson back about 7 years ago, but it was not even fully open when the new VSE closed it down. Tony was building an MLT at the time. If Marshall were to reopen the center, Tony could build a balance in no time and characterize it within a month. They already have lots of vacuum and with the lessons learned the last few years, I think MSFC could have good replication data inside a year. Just don't hold your breath. Likewise, Lock-Mart, Boeing, Northrup-Grumman, and many others could step forward once Jim's book is out and ask to do a replication. They're all set up to do such a project with ease. The question is will they.

As far as the "just so conditions" etc. most of the sensitive issues concern the power system. Putting an accomplished EE on a design team is enough to remove most of the problems we've seen to date. The current issue, that the thruster needs to be in both acoustic and electrical resonance to provide the high thrusts we've seen is actually not a difficult thing to do. I found an amp that has a PLL circuit built in such that it automatically searches for the resonance of an attached piezo transducer and runs at that resonance. That little box sold for $50 last October before I could snatch it up. All by itself, that would make it possible to do all manner of tests we have not yet seen Jim do. New, such amps cost a mere $3,400 so that is certainly inside the budget for any professional replication. It operates from 20-120 Khz, so dozens of cheap thrusters can be constructed from Steminc stuff on EBay (what Jim is currently using) and run with this single power system. One could use rings instead of discs and a single bolt clamp--there are host of things that could be altered to make very small enhancements in the utility of the system for very advanced studies. And of course, running up around 120 Khz should produce much larger thrusts than we've seen to date, without messing with the type ceramic.

So sad to say, but the skills necessary for this are pretty common and easy to get. Just needs the right person to take an interest. Lets hope the book helps in that regard.

MSimon · Post by **MSimon** » Mon Dec 17, 2012 12:29 pm

GIThruster wrote:There are a handful of labs around the world that could do replication work fairly cheaply. George Hathaway up in Canada could do it. EarthTech could do it. Sonny White's Eagleworks lab could do it. These are all pretty heavily invested in ZPF however, and some have a personal stake to see the work fail. I would not want to use any of these labs for that reason.

Marshall Space Flight Center opened a new $40 M advanced propulsion research center run by Glenn "Tony" Robertson back about 7 years ago, but it was not even fully open when the new VSE closed it down. Tony was building an MLT at the time. If Marshall were to reopen the center, Tony could build a balance in no time and characterize it within a month. They already have lots of vacuum and with the lessons learned the last few years, I think MSFC could have good replication data inside a year. Just don't hold your breath. Likewise, Lock-Mart, Boeing, Northrup-Grumman, and many others could step forward once Jim's book is out and ask to do a replication. They're all set up to do such a project with ease. The question is will they.

As far as the "just so conditions" etc. most of the sensitive issues concern the power system. Putting an accomplished EE on a design team is enough to remove most of the problems we've seen to date. The current issue, that the thruster needs to be in both acoustic and electrical resonance to provide the high thrusts we've seen is actually not a difficult thing to do. I found an amp that has a PLL circuit built in such that it automatically searches for the resonance of an attached piezo transducer and runs at that resonance. That little box sold for $50 last October before I could snatch it up. All by itself, that would make it possible to do all manner of tests we have not yet seen Jim do. New, such amps cost a mere $3,400 so that is certainly inside the budget for any professional replication. It operates from 20-120 Khz, so dozens of cheap thrusters can be constructed from Steminc stuff on EBay (what Jim is currently using) and run with this single power system. One could use rings instead of discs and a single bolt clamp--there are host of things that could be altered to make very small enhancements in the utility of the system for very advanced studies. And of course, running up around 120 Khz should produce much larger thrusts than we've seen to date, without messing with the type ceramic.

So sad to say, but the skills necessary for this are pretty common and easy to get. Just needs the right person to take an interest. Lets hope the book helps in that regard.

What you want is something called an oscillator. If you put a tuned circuit (the piezo and the ceramics) in the feedback loop of an amplifier you get an oscillation at the resonant frequency. (you also have to get the phase right - a minor detail and have enough gain - not too difficult) If you do soft limiting and a little buffering you can get fairly good sine waves out of such a rig.

I don't know why you would want a PLL unless it was important to operate at a very fixed frequency. Or maybe to multiply up the oscillation frequency for sampling purposes. If I was running a rig at ~100KHz I'd want samples at a 16X rate or even 128X or 256X depending.

I will go this far - you propose a circuit and I'll critique it. That is one way of getting it designed.

Stubby · Post by **Stubby** » Mon Dec 17, 2012 2:25 pm

perhaps due to lack of sleep, but I found Lock-Mart to be hilarious.
Nice big box factories! All painted blue with greeters inside the front doors.

GIThruster · Post by **GIThruster** » Mon Dec 17, 2012 6:49 pm

MSimon wrote:I don't know why you would want a PLL unless it was important to operate at a very fixed frequency.

PLL Allows the circuit to adjust to the changing temperature of the transducer when its run for extended periods of time. One of the goals is for more control, and the ability to generate large thrusts all the time is part of that goal. To do this you need to be able to produce large amplitudes by running on resonance regardless of the temperature of the stack, which can change the resonance by a Khz or more.

Basically, what you want is something like this:

http://ntrs.nasa.gov/archive/nasa/casi. ... 024165.pdf

chrismb · Post by **chrismb** » Mon Dec 17, 2012 7:03 pm

GIThruster wrote:...the ability to generate large thrusts..you need to be ..running on resonance ...

MSimon wrote:If you put a tuned circuit (the piezo and the ceramics) in the feedback loop of an amplifier you get an oscillation at the resonant frequency.

(GIT = EE fail)

GIThruster · Post by **GIThruster** » Mon Dec 17, 2012 7:53 pm

I should note there are other issues. The matching circuit needs to match power at 2 different frequencies simultaneously. Really the best thing for this is an over-coupled resonant transformer. With that sort of power system Jim would be freed up to use some of the very high quality ceramics we've talked about like PMN-PT with dielectric constants more than 40X higher than the PZT he's using, higher electromechanical linking coefficient, lower loss and cubic structure than can't depolarize. The thing with electrostrictors is they have no 1w piezo action so they need to be driven with a 1w+2w wave, which means matching at 2 frequencies simultaneously. For that you want a resonant transformer.

MSimon · Post by **MSimon** » Mon Dec 17, 2012 8:47 pm

GIThruster wrote:
MSimon wrote:I don't know why you would want a PLL unless it was important to operate at a very fixed frequency.
PLL Allows the circuit to adjust to the changing temperature of the transducer when its run for extended periods of time. One of the goals is for more control, and the ability to generate large thrusts all the time is part of that goal. To do this you need to be able to produce large amplitudes by running on resonance regardless of the temperature of the stack, which can change the resonance by a Khz or more.

Basically, what you want is something like this:

http://ntrs.nasa.gov/archive/nasa/casi. ... 024165.pdf

If you run your VCO at 4X (not difficult at these frequencies) you can use a Tayloe Detector. The Tayloe is good for low output transducers because all the amplification takes place at the base band. i.e. 1 KHz and below. But the transducer has to be clean. No wandering glitches.

I'm currently working on just such an artifact for a different purpose.

For a VCO I like the one in the 9046. 74HC I think but I'd have to look it up. Another option is to use the 9046 as the phase detector in the low voltage input mode.

Design of such a system is easy. It is the debugging that is difficult.

GIThruster · Post by **GIThruster** » Mon Dec 17, 2012 9:07 pm

MSimon wrote:Design of such a system is easy. It is the debugging that is difficult.

I believe you. Several EE's have said this over the last few years, but none of them have designed, debugged and built such a system. And this is why I say that despite we want to see new ceramics, new designs, higher frequencies, more thrust, what is needed more than anything else is a salary for an EE in the lab. There are plenty of people able to solve the power system problems we have, but they need to be paid.

This is why I'm so annoyed at NASA that they aren't even interested in a NIAC grant. According to Jay, NIAC is okay with funding TRL 1-3. They're just not available to be the first to fund TRL-1-3. NIAC is a sham.

93143 · Post by **93143** » Mon Dec 17, 2012 9:35 pm

chrismb wrote:
GIThruster wrote:...the ability to generate large thrusts..you need to be ..running on resonance ...

MSimon wrote:If you put a tuned circuit (the piezo and the ceramics) in the feedback loop of an amplifier you get an oscillation at the resonant frequency.
(GIT = EE fail)

You need electrical and mechanical resonance simultaneously.