What the vast majority of cave and mine explores want is
RELIABILITY!
Design a bomb proof lamp that can be worn all day.
In wet & muddy conditions and keep working.
That will take knocks and bangs without falling apart.
With reliable switches and cables that don't break.
(Sorry, been looking at the Oldham again!):angel:

I do a bit of Oldham servicing for a couple of CapLamps.co.uk customers. In a typical 6 month operating period out of around 90 lamps we'll see:

2 to 3 blown pilot bulbs
4 to 5 blown main bulbs
4 to 5 cable replacements (usually perished at the lamp entry)
4 to 5 perished cable gland (battery top exit)
1 to 2 broken keyway slots "lock contact"
2 to 3 broken bezels
5 to 6 blown fuses
5 to 7 broken wires on the reflector bush connection assembly (solder or replace)
1 to 2 switch problems - varying from cracked plastic to worn through contacts
An increasing number of dead cells (good for an hour or so, not good for a shift - and as Roy mentioned in another thread, there's a disproportionate number of newer cells failing and the old T2s seem to keep going)

These lamps aren't getting 10 hours a day 50 weeks of the year hammering.

Reliable yes 🙂 And even more impressive for the fact they are 20 or 30 years old.

But not indestructible and by the end of the 6 month season there will be 20 or more lamps needing attention.

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I can recall many instances where the good old traditional cap lamp resulted in many headaches etc underground, in most cases while walking along tunnels/drives etc, the long beam was great for seeing what's in the distance but not very good for making you aware of the presence of objects that were just ahead of you at just above head height or what was below at foot level whilst looking straight ahead, eye pegs and track sleepers come to mind..Ouch.

The ones we had were were just main beam and pilot light, a problem would sometimes happen if both the main beam and pilot light failed when miles from anywhere underground, it happened to me only once, not a particularly nice experience.

Lozz.

Heading back to the original concept, I am a bit uncomfortable with the idea of the light deciding how bright it is as the last thing I want when walking over rough ground is the lights to suddenly drop! Automatically switching off when you get back out to daylight might be good though could be a pain in places that have been opened to day.
The added complexity of the circuitry means more chance of failure, this isn't a comment on the design per se, just a general rule. Simply put, in a hydraulic system more joints = more possible failure points.
In my day job as a design engineer I try to design stuff with the "Add lightness and simplicate" motto in mind, along with "If string works, use string".

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Making a circuit more complex doesn't mean that it is more prone to failure ie: the microprocessor in a computer in it's current form (the chip) it's far far more reliable than it's equivalent would be if it were to be made from good old traditional separate passive and active components.

The fact is that most UG explorer folks these days seem to use LED lighting, that in itself increases the complexity of the system used to supply the LED with power because the LED is primarily a constant current device, that in turn requires an electronic loop in order to maintain a constant current, that extra complexity doesn't mean to say that the system as a whole is more prone to failure, in fact it would me more prone to failure without a control loop due to the nature of the voltage versus current curve of the LED device.

Beware of mechanical-electrical analogies, some times it can make things more confusing and less understandable.

Lozz.

Yeah but no but...
As well as mechanical failure points in the components & the joints you then add in software failure points!
The design life of the components used in led lights is several orders of magnitude higher than for filament bulbs and the component solder joints are equally long life. This leaves the significant failure points as flying leads (limited need for these in an led light), mechanical switching & software.
Obviously if the housing isn't well designed, eg insufficient heat dissipation, then this will cause premature failure which could be attributed to the component that fails but is because it was having to work outside its comfort zone.

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Normal everyday shock/hitting it with a hammer etc aside, the reliability of a soldered connection is most commonly governed by the quality of the soldered connection in the first place and by differing rates of expansion/contraction between the metals involved including magnetostriction.

Badly soldered joints, dry joints and heat being the most common problems I've encountered in that area.

Anyways, back to the OP's original post, seems that Petzl have already cottoned on to the reactive light thing, maybe the OP can improve on that on a cost basis, or fine tune that arrangement specifically for underground situations?

Can the illumination ie: flood/beam/intensity be controlled by the user but in a hands free way?

Lozz.

I debated how to control mine a lot. I wanted to do a ribbon controller, but I'm not sure how it would stand up to an underground environment. I think I've settled on an analog sealed potentiometer inputting to a micro-controller with a pre-programmed logarithmic curve in it. This would override the LDR input.

My LDR levels will be be controlled only by the light levels or the override, at least initially. This will also take some time.

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Hey guys, thanks for all your replies, they have all been extremely helpful in formulating a final design concept, which I have included in the following link.

If you can spare 3 minutes to fill out a quick survey about the product for the quantitative part of my market research that would be greatly appreciated and any additional feedback can be posted here or in the survey if you see any major flaws.

Thank you in advance.


https://www.surveymonkey.com/s/VX5CC6R 

Done this myself and been up and running for two years, although mine is a fairly simple passive affair with no logic control on the feedback side of things. It really does not need to be that complicated IMO unless you are swapping between flood and spot modes etc..
I replied to the UKC thread with a piccy and outline of my experience.
http://ukcaving.com/board/index.php?topic=16900.0 

Done this myself and been up and running for two years, although mine is a fairly simple passive affair with no logic control on the feedback side of things. It really does not need to be that complicated IMO unless you are swapping between flood and spot modes etc..
I replied to the UKC thread with a piccy and outline of my experience.
http://ukcaving.com/board/index.php?topic=16900.0 

Nice to see this in person today, it's well made, and looks like a factory mod externally.

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Yes nice to meet you Ally, and thanks for the compliment!

Auto adjustment and playing with colour temp will attract a few (all be it vocal) players.
Hundreds of lumens are usefull for about 1% of underground work.
What the vast majority of cave and mine explores want is
RELIABILITY!
Design a bomb proof lamp that can be worn all day.
In wet & muddy conditions and keep working.
That will take knocks and bangs without falling apart.
With reliable switches and cables that don't break.
(Sorry, been looking at the Oldham again!):angel:

I am sorry but Colin says it all here.

Some may have derived amusement from my little rhyme, but serious thought about the points I made in it are worthwhile.

Like I said, the ability to THINK.

Technology is wonderful when it gave us the LEDs, the efficient electronics to go with it, the ability to communicate across the globe with little devices that slip into the pocket, cars that can deliver over 200 b.h.p. and still do over 40 to the gallon (I especially like the last, LOL). But when it starts to take over, for me as many others, its no, no, no.

Sorry, but when I first saw this thread my first was horror, then disbelief.

Anyway, off thread, well slightly, but another one of my prophesies has come true, but it hasn't gone mainstream yet.....

Out there, lurking ominously...... A CHINESE SCURRION CLONE

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Auto adjustment and playing with colour temp will attract a few (all be it vocal) players.
Hundreds of lumens are usefull for about 1% of underground work.
What the vast majority of cave and mine explores want is
RELIABILITY!
Design a bomb proof lamp that can be worn all day.
In wet & muddy conditions and keep working.
That will take knocks and bangs without falling apart.
With reliable switches and cables that don't break.
(Sorry, been looking at the Oldham again!):angel:

I am sorry but Colin says it all here.

Some may have derived amusement from my little rhyme, but serious thought about the points I made in it are worthwhile.

Like I said, the ability to THINK.

Technology is wonderful when it gave us the LEDs, the efficient electronics to go with it, the ability to communicate across the globe with little devices that slip into the pocket, cars that can deliver over 200 b.h.p. and still do over 40 to the gallon (I especially like the last, LOL). But when it starts to take over, for me as many others, its no, no, no.

Sorry, but when I first saw this thread my first was horror, then disbelief.

Anyway, off thread, well slightly, but another one of my prophesies has come true, but it hasn't gone mainstream yet.....

Out there, lurking ominously...... A CHINESE SCURRION CLONE

Would you care to expand on the Scurrion clone.

Rick, tomorrow I will open a new thread, late now.

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Roy, why not make one yourself and try it out?? You might be surprised ;)

For cavers at least with a mixture of squalid crawls and open chambers there are advantages to this design. The lamp only outputs the light that is required and so battery life is extended by some duration.
My converted Oldham uses the two switch settings to choose between the Chinese module and my own circuit, common 7135 drivers but as each is paralleled up there is enough redundancy built in that only battery or LED failure could ever prove a problem!

The only problem with my design is that I am running XML's and under-running them to keep heat down, so I either need to switch to XPG's or develop a new enclosure entirely, something I hope to do later this year!

Never in 1000 years will technology ever be a substitute for the human brain, all it will achive is to make a nuisance of itself in the attempt.

I have not always thought like this, I was originally open minded, my opinion is based on experience. But too many instances of things doing something off their own bat that I didn't want them to do and never asked them to do.

I can see the day when cars have proximity sensors of some kind to prevent forward movement when an object is within a certain distance.
So you end up broke down on the motorway on a wet night because a dead fly or something is in the wrong place.
This where we are going.

So all you people who develop this sort of technology, dont forget the vital bit, the ability to DISABLE.

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Trouble is the human brain is a broad brush, some folks appear to have no brains whatsoever and some folks do.

Technology is fine, it's peoples inability to fully understand it and the consequences thereof.

Lozz.

The problem is that if you take away the necessity for people to think and make decisions they will entually loose the ability to do so.

Keep dumbing everything down and eventually we all become dumb

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The problem is that if you take away the necessity for people to think and make decisions they will entually loose the ability to do so.

Keep dumbing everything down and eventually we all become dumb

Or it releases more brain power to come up with even more technology. :)

Lozz.

Fellows Lamp Mission Statement

Do continuously strive to produce lamps that are more efficient so as to provide exceptional performance combined with a reasonable weight and smaller lighter batteries, whilst at the same time maintaining superb core reliability.

But the only person who will ever be in control of the thing will be the person wearing it.

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