Latest Minelab Patent - 11th Feb 2016

[Davor]

Just the story. It most certainly is inspired, so it must have a good story.

[Dave J.]

Could you be bothered to elaborate on the making of CZ5? It is a great machine and it surely must have a story behind it. If not here on some dedicated topic?

Well, this thread has already been clogged with off-topic stuff, I don't suppose a post on the CZ5 would do any additional harm. What was it you wanted to know?

[Teleno]

It also do not ground balance and paper say problem of exactly what the patent solve! It say “The response due to the magnetic properties of the soil can also influence the DSRF since the response of the soil is superimposed on the response of the target and it is not possible to completely separate the two.”

You keep repeating that the patent solves the GB problem but as I earlier pointed out, the patent discloses no such a thing at all.

So let me challenge you to quote the patent where it supposedly discloses GB (not simply mentions it in passing) in such a way as to allow the skilled person to duplicate the alleged technique. Once you post here the juicy bits (if you find them) we'll see whether it's known from the prior art or not.

So please, cut down on your own text and point us to the literal subject matter, if it exists.

Also, “UXO time-constant estimation from helicopter-borne TEM data” have no ground balance, and do not generate TC spectrum only single TC in results (but do mention TC spectrum)

You certainly lack understanding of what a time constant spectrum is.

The definition of discrete SPECTRUM is "decay parameters (time constants and weights)" (page 8 ). The signal is "decomposed as a weighted sum of pole responses" (i.e. a discrete SPECTRUM ):

The expression above represents a discrete time-constant spectrum. This fact flew over your head, another strong indicator that you know little about what you're talking about. Whether the word "spectrum" is mentioned or not is irrelevant, the disclosure is there and the skilled person understands.

Then on page 9:

"...two time constants were estimated ... for this example .. approximating the two strongest eigencurrent modes in the plate model..."

So you're proven wrong again, the paper does disclose a two-time-constant approximation of a target just like ML's "invention" does.

[Davor]

Nope. Voltage supplied to the inductive reactance is what does it. The physical coil has series resistance -- plenty of it-- and some of the voltage gets dropped across that. To make matters worse, in the case of a perfect inductor knowing the voltage at any point in time tells you nothing about the current because the two things are 90 degrees apart. If you want to know what the magnetic field is, you have to know the current. This is ordinary high school physics.

OK, I see your point. I normally don't go to the parasitics when trying to present a concept in its simplest form, but again, you are right.

My view of the practical coils is that they are mostly of considerable Q factor in a working frequency range. Series resistance is very obvious with shorted coils that refuse to produce constant field, but instead you have some reactive component.

Could you be bothered to elaborate on the making of CZ5? It is a great machine and it surely must have a story behind it. If not here on some dedicated topic?

[daverave]

Except for occasional effusion of unnecessary arrogance by some people, I do not see anything special educational in this whole debate.
I think that it is precisely the presence of this arrogance prevents that the debate goes in the right direction.
Egocentricity and arrogance otherwise spoil the many topics on this forum.
So that all of this became very boring.
It all boils down to masturbation some of these arogant people who seem to have no other ways of pleasure in life.
Whichever professional achievements that man has; become completely irrelevant and void by the presence of such arrogance.
And such people are good for avoiding and ignoring.
The theme revolves around, nothing new has been said, nothing was found.
People from ML are probably lauhing to death reading this.
So this is all very comical and pathetic.
And those who were arrogant, and who think of themselves are worth more than others; better yourself sit down and learn something more than what you know.
It's one thing to know for real and another to be the turkey struts with colorful feathers, tossing empty words around.
When you can not find the right answers; then along comes this course of behavior and action.

Whether he was joking or not, KT315 gave here pretty sane and honest question and doubt.
In the spirit of this forum, it should be just tried to answer on that.
Several nice people tried to do that.
Some of not so nice people took advantage of the situation to show their arrogance which is also their weak point.
Now we know that from such can not expect any contribution here.
I can not participate in such a story, i'm sick of these kind of people.
And my last advice would be; do not continue to give cause ML people to laugh!
They did a job and now they taking a money for that... while you here are wasting your (and our) time by empty debating.



https://www.youtube.com/watch?v=XKk5KGp6Foo

i find some of the input of this discussion very daunting...ok there are some high tech people on here that do this for a living but it makes one feel very small in comparision when some of us are mere mortals and just hobbyists....even with all these big statements of high tech jargon what does it all add up too.......how far have modern motion machines and such like have come ???? take away fancy lcd displays and gimicks compared to old technology how far have we really come ???? but marketing wants to make us believe the la
test tech is the best...but in reality maybe not !!! even home hobbyists can equal and better the depth on high end machines at a fraction of the cost........i know of someone who used an old arado 95 and he has found more gold over the years with that old machine than many will find in a life time with their modern dual frequency...bbs...dvt....vflex and such like.

[clancy]

Teleno, you do what many do on forums. Spot few “key-sounding” sentences and post these as “proof” paper or patent say that you want forum viewers to believe it say. Lucky in academic scientific nobody can cheat like this.
You say “TC spectrum” taught in this paper “UXO time-constant estimation from helicopter-borne TEM data” on page 8, and Wei, Scott, McClellan paper “discloses ground balance using the same technique.” This be not true. What Wei paper do, is see if Rx signal = soil well-known log-uniform VRM signal and if it do, then no target present in Rx. Only if Rx be different to soil log-uniform VRM signature, only then must be target detect, and only then data use for generate target TC spectrum from Rx data without any ground balance.

Thank you for last bonus paper. Note this written by same author Wei of paper above. It also do not ground balance and paper say problem of exactly what the patent solve! It say “The response due to the magnetic properties of the soil can also influence the DSRF since the response of the soil is superimposed on the response of the target and it is not possible to completely separate the two.”
Excellent proof that how to GB and then generate TC spectrum be NOT OBVIOUS. Thank you Teleno for this proof. If you still think GB then transform to TC spectrum be obvious, maybe you write to Wei, Scott, McClellan and tell them they stupid?

I see you cannot answer my questions to you. Only if you can, only then you understand why patent solve problem of ground balance then transform to TC spectrum for first time be not obvious. The 2 numbers ask you be very different to each other.

If you read patent you see it point out problem that Wei (et al) (who you cite twice) cannot solve:
“It is known to demodulate receive signals of a metal detector for processing to characterise the receive signals in terms of time constants. WO/2011/011820 discloses that discrimination of a target to a certain degree can be achieved by analysing the spread of the time constants. Mu-Hsin Wei, Scott, W. R., McClellan, J. H., “Estimation and application of discrete spectrum of relaxations for electromagnetic induction responses,” Geoscience and Remote Sensing Symposium, 2009 IEEE International, IGARSS 2009, vol. 2, no pp. II-105, II-108, 12-17 Jul. 2009 discloses that by identifying each of the main frequency components (inversely proportional to time constant) of the received signals, it is possible to enhance discrimination. Mu-Hsin Wei, Scott, W. R., McClellan, J. H., “Landmine detection using the discrete spectrum of relaxation frequencies,” Geoscience and Remote Sensing Symposium (IGARSS), 2011 IEEE International, vol., no., pp. 834,837, 24-29 Jul. 2011 discloses a pre-screener to ignore cases where substantial soil signals are present.”

Also, “UXO time-constant estimation from helicopter-borne TEM data” have no ground balance, and do not generate TC spectrum only single TC in results (but do mention TC spectrum), and it not sync demodulate then LPF, but get TC from time data, but it say that this technique have poor s/n: This be why patent synch demodulate then LPF to get good s/n.

[kt315]

half brigde + half bridge you get a bridge

this driver from Koschej. you can use it with resonance coil or un-resonance coil. you may call your detector either PI or hybrid - on your choice.

[Beav]

Carl. I got a Kick out of your term "cleverneering"! It suits engineering to a "T"! LOL
Thanks for making me chuckle!
Beav

[Carl-NC]

Except for occasional effusion of unnecessary arrogance by some people, I do not see anything special educational in this whole debate.

The reason I keep coming back around to the BBS transmitter and how it works (as opposed to how people believe it works) is because, for those who are interested in moving to a MF design, it's a really good way of getting there. With just a micro and a few MOSFETs, you can have a very flexible transmitter that can do 1, 2, 3, or more frequencies, in any ratio you like, all selectable at run-time. Add some vanilla demods and the rest is Fun with Signal Processing.

But here's another tidbit: The Impulse transmitter design can do what the BBS transmitter can do, but more. This becomes apparent by playing around with it, preferably in Spice as Davor suggests. It can even produce a simultaneous hybrid VLF+PI waveform. With a little cleverneering, it will do multi-frequency hybrid VLF+PI. The prototype I had running was pretty impressive and exciting, and one day I may resurrect this concept as well.

[Carl-NC]

I never met Don, but I did get the chance to dig through his notebooks. I liked his work. I was told the MF design he did worked brilliantly when it worked, but it didn't work often enough and the project dragged on too long. (Unfortunately the prototype had disappeared.) It was, in my opinion, too far ahead of the chips that were available at the time. With DDS and powerful 32-bit micros, it might be the kind of project you'd resurrect and turn into a commercial product.

[Taktyk]

Shoemaker. I know only patent 5900/6000.
I know your detectors Fisher CZ5 it is not simple Dave Thank you for your reply. Your projects are always an inspiration for me.
I was looking for a solution for the multifrequency detector but other than it is now - the emission signal based on the network reactive impedance - as the MXT (control signal TX by integrator). Only it works for the two frequencies 3kHz and 30kHz Program loop is 1mS - the project is based on the platform of Cortex M4.
Below prototype detector.
Regards

[Dave J.]

http://www.google.com/patents/US5642050

Shoemaker. I knew the guy, Carl probably never met him. His apparatus was a horribly complicated mess that was almost impossible to get working even on the bench, but he did prove that you could discriminate iron in the multiple frequency domain. Unfortunately the apparatus itself was not the basis of a manufacturable product, so to get an actual product they hired me to design the circuit that became the DFX, which is of the same general sort as the CZ although not in any sense a copy.

The story then takes an even stranger twist. The engineer on the DFX project was Rowan, and he'd absolutely insisted that iron couldn't be discriminated using multiple frequency methods--- despite Shoemaker's patent! I showed him how to do iron discrimination on the DFX platform, but he refused to do it because he'd already told Mr. White it couldn't be done.

The first swinging multifrequency machine I built approx. 1984 used multiple frequency methods to do iron ID, although under weak signal conditions it helped itself to the reactive signal single-frequency style. That particular platform was not sensitive enough or reproducible enough to become a manufacturable product, but it established the principles involved. It was all-analog, too-- no microprocessor. And on our freshwater beach test site with granite-derived sand containing a lot of magnetite, it did just about the same thing in the ground as in the air and you didn't dig any trash you didn't want to dig.

In this industry there's gobs of stuff that's been done and gobs of other stuff which folks have known how to do although they may not have actually done it, that never saw the light of day. The reason for that is that a commercial business has to decide what is most likely to actually produce a return on investment and then to invest in that, and those other possibilities (some of which might even be better investments but management doesn't know that) don't get funded. Business is guesswork.

[Taktyk]

Carl M.

Plural frequency method and system for identifying metal objects in a background environment using a target model US 5642050 - why he did not see the light of day? I ask because
you worked in white's...

Does anyone have any other materials of this inventor?

Regards
TAKTYK

[kt315]

KT 315 so many years on the forum Geotech and you still do not understand the basics.....

T.

RTFM ITMD.

[Taktyk]

KT 315 so many years on the forum Geotech and you still do not understand the basics.....

T.