Automatic And Variable Recovery Speed?

[Digalicious]

Johnny,

When I first read your post, my thought was "Huh"? Then after a moment of thinking about it, I realized that you're correct. That is, the detector wouldn't have to know the speed of the coil. The only data point the detector would need to know, is the time interval between targets, then an algorithm would adjust the recovery speed accordingly. Hmmm 🙂

I don't know if I'm missing something obvious, but this would seem like a great feature to have, considering the density of targets can change quickly and dramatically on multiple areas of a particular site. For example, I go to site, take a few swings and realize the target density is so high that I decide to use a very fast recovery rate. Yet, a few feet over, the area has low target density, but I'm now needlessly losing significant depth because of my high recovery speed. That can easily happen continuously on many sites, wich results in many missed targets. An automatic recovery speed mode should solve that problem, in the same way automatic ground tracking solves the issue of varying ground mineralization.

 

[Bill (S. CA)]

Personally I would be very interested in Geotech's (Carl) thoughts on this.

[Digalicious]

29 minutes ago, Bill (S. CA) said:

Personally I would be very interested in Geotech's (Carl) thoughts on this.

Me too, or thoughts from anyone that can explain the technicalities behind such a mode.

Given the serious performance loss due to an incorrectly set recovery speed, I would think a mode that would count targets and adjust the recovery speed to match the target density, would be an obvious, "no brainer" feature. Given that no detector has such a seemingly important feature, I'm leaning toward the engineers have already thought of such a mode, but realized that all the variables would cause the mode to be inaccurate.

 

[Chase Goldman]

On 4/13/2023 at 11:39 AM, Digalicious said:

Point # 1 seems silly to me. I mean how hard is it to press that button that's right beside your thumb when you occasionally ground balance? Also, I'd be worried that it would automatically go into ground balancing mode just by natural or inadvertent movement of the coil.

Frankly, the Quest implementation of sensed coil pumping to initiate GB makes more sense to me (than an automatic recovery speed adjustment feature) as I often encounter areas where I need to do frequent manual ground rebalancing due to shortcomings or downsides to automatic (ground mineralization sensing based) ground tracking that either can't keep up with ground phase variations or that can cause weak target signals to be missed.   In fact, I could make a similar statement regarding implementing automated adjustment of recovery speed.  That is, how hard is it to simply manually bump the recovery speed up or down based on the number of targets encountered in in a single sweep.  Also, the perceived change in target density (sudden machine gun effect) with constant manual sweep and machine recovery speed is the thing that alerts me that I am in an area where I need to concentrate on the target signals and also alerts me to the boundaries of the high density target patch.  The key to that perception is keeping recovery speed and sweep speed constant but high enough to not significantly affect depth while being able to perceive high density situations.  I personally would rather be making the conscious decision myself on trading off depth vs. recovery speed, for the reason stated.  Not sure whether my routine would be adversely impacted by an automated recovery speed adjustment, having a little trouble visualizing how it would change things for better or worse, TBH.

Note also, having the ability to adjust recovery speed manually or otherwise as a basic feature is a relatively recent trend.  For the longest time the ability to change recovery speed independent of other features with the range of adjustability that is commonplace now, was a feature present only on the Deus (yes, there were limited fast process, mode-based recovery speed adjustments available on Fisher, Whites, Nokta/Makro and other machines over the years, but they were much more limited than the implementation you see on Equinox, D2, Legend, Quest V series, and Manticore today). 

I agree that it should be a relatively simple feature to implement utilizing coil accelerometers as swing sweep sensors and counters.  But I think the real reason we are not seeing it that it is just not something users are clamoring for, so manufacturers are not inclined to go to the trouble to implement it.  I may be a Luddite, but I personally see the feature as a solution looking for a real problem statement.  I am not really seeing a compelling use case, but then again, I am also in the camp of detectorists that like a wide range of manual parameter adjustability but less automation of that adjustability whether it has to do with ground tracking, gain (transmit power or sensitivity) adjustments, noise elimination, dynamic adjustments in target signal volume, or the suggested auto recovery speed feature.  I may come around on this particular feature suggestion but just not yet seeing how it can significantly enhance my detecting experience.  That's just me.

[Digalicious]

Chase,

I don't recall anyone saying, "I can't believe I have to slightly move my thumb and press this button when I do a ground balance!" Oh the humanity! 😉

Further to that, not having to occasionally press the GB button, does nothing to increase performance. As such, I would consider that feature, "grasping at straws" to come up with something to make the detector have a feature that other detectors don't. But I digress, as the point of this post is about a possible feature that has the potential to significantly increase the number of good finds.

If someone isn't using any discrimination, and has the iron volume on, then sure, they can hear all the targets and constantly adjust their recovery speed...but how many actually hunt like that? Even if they did hunt like that, it would be a welcome feature for the detector to able to change the recovery speed on the fly, instead of the hunter having to push a bunch of buttons every time the target density changes.

Also, good point when you said, "having the ability to adjust recovery speed manually or otherwise as a basic feature is a relatively recent trend". Ok, the adjustable recovery speed option is rather new in the regard as you described, and could be a reason why automatic recovery speed hasn't been implemented. Perhaps the next natural progression, is to maintain the manual adjustment, but have the automatic setting as an option. 
 

[Jeff McClendon]

1 hour ago, Digalicious said:

not having to occasionally press the GB button, does nothing to increase performance. As such, I would consider that feature, "grasping at straws" to come up with something to make the detector have a feature that other detectors don't. But I digress, as the point of this post is about a possible feature that has the potential to significantly increase the number of good finds.

Every detector that I own has some form of automatic ground balance tracking where no button press is technically necessary. However, very few of the places where I detect are good candidates for automatic ground balance tracking so I rarely use that feature. Instead I sometimes end up ground balancing a dozen times or more during a hunt. I sometimes even have to ground balance after every detected target due to how hot the ground is. So, having the ability to avoid doing a forefinger or thumb (often with thick gloves on) button press ground grab without having to press a button or multiple buttons in the case of one particular detector I own, is an extremely attractive feature for where I often use a detector and is directly related to an increase in performance.

My sentiments about automatic recovery speed tracking are similar to those about automatic ground balance tracking. Mineralization conquers all, and recovery speed, just like ground balance can be adversely influenced by ground mineralization. I have yet to see a high end VLF or Pulse Induction detector that can actually keep up software wise with many of the places I hunt if I let the detector try to do things like track ground balance automatically.

[Digalicious]

Can you imagine having the best separation and the best depth, at all times, because your detector is able to set the best recovery rate as you swing? If such is possible, I believe most hunters would consider that a true game changer.

The more I think about an automatic recovery speed mode, the more I think it has the potential to be the next main selling point of future detectors. If it can be accomplished effectively, those detectors would fly off the shelves.

[Digalicious]

I previously mentioned that the whole idea may not work due to the variables. What I meant by that, is that the target density simply changes too frequently. In other words, even if we take a small 20' x 20' area for example, the target density can change so much in that small area, in one swing a low recovery speed would be ideal, and the next swing, a high recovery speed would be ideal. I can't see how an auto recovery mode would be able to accurately keep up with that.

If the above is the road block to auto recovery speed, then what about simultaneous recovery speed? For example, the first pulse is transmitted with a low recovery speed, and a nano second later, the second pulse is transmitted with a high recovery speed. Those are then combined to get the "best of both recovery speed worlds". 

[Chase Goldman]

3 hours ago, Digalicious said:

If someone isn't using any discrimination, and has the iron volume on, then sure, they can hear all the targets and constantly adjust their recovery speed...but how many actually hunt like that?

Don't know how many hunt like that, but that's what I do.  More precisely, I use discrimination WITH iron volume on D2 because Disc as implemented on D2 is not just a ferrous signal silencer, it helps to better differentiate ferrous vs. Non-ferrous targets in proximity to one another and mitigates ferrous down averaging of non-ferrous IDs.  I use iron volume to tell me where concentrations of ferrous targets exist because that tells me where human habitation existed (when the visual clues have been erased by time).  FWIW.

1 hour ago, Digalicious said:

Can you imagine having the best separation and the best depth, at all times, because your detector is able to set the best recovery rate as you swing? If such is possible, I believe most hunters would consider that a true game changer.

Well, there are no free lunches in detecting.  It's a constant struggle of managing tradeoffs.  So, in reality you can't have best depth AND best separation simultaneously because one parameter works in opposition to the other, automated or otherwise.  There may be an optimal balance point, but what criteria would you use to determine that (like you said, too many variables)?  In high target density I am utilizing high recovery speed to find the shallower keeper targets that are hiding amongst the iron and that have hopefully been left behind by previous detectorists with slower machine.  Selecting that recovery speed is a trial and error process that relies on "feel".  It's imprecise and somewhat subjective.  I have no expectation of depth.  Also, when I'm in "machine gun" target density situations, my swing tempo and amplitude is highly variable as I try to lock in on keeper targets in the " muck", so auto recovery might be a hindrance and counterproductive.  If I want depth, auto recovery speed is not going to do it, removing the iron and trash piece by piece is necessary and tedious to achieve that end.  However, great strides in AI and machine learning have been made of late, so I'm not saying we'll never have a machine learn in real time based on the detectorist's manual adjustments someday that is able to emulate what we do by intuition and experience today. Might be ways off and detector manufacturers are going to have to decide whether the return on investment and cost passed on to consumers for that effort is going to be worth it.

Frankly, in the mean time, just give me accurate target ID at depth under a wide range of soil conditions and give me on demand fast recovery for proximity trash targets and I'm good.

[Digalicious]

Chase,

It's my understanding that SMF isn't true simultaneous, but rather, extremely fast sequential. If so, then what about what I mentioned in my previous post, in regards to kind of making the recovery speed "simultaneous" as well?

12 hours ago, Chase Goldman said:

 

Frankly, in the mean time, just give me accurate target ID at depth under a wide range of soil conditions and give me on demand fast recovery for proximity trash targets and I'm good.

I'm thinking we have detectors that already do that quite well. Give me a detector that can distinguish aluminum from gold and I'm good 😁