Of cases and batteries


thatgui

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How is situation 2 worse than situation 1? And situation 2 is basically a worst case scenario, at least some cables will never progress far enough to break the redundancy. So as near as I can tell, outside of a few extra cents for wider cables, the redundancy is strictly better: those that would have broken either get more usage or never notice that anything is wrong.
Because of this
Shouldn't the real question be is why the LCD cable wearing out in the first place?
 
Is there a webpage which counts interested buyers?

All peoples who are interested in buying a Pyra could register.

I think it would be helpfull if Evildragon could see how many pieces he will sell.
There is a subscribe button on http://www.pyra-handheld.com/
Is it possible that the traces on Pyra's cable can also be made thicker? Does that make any sense as an additional mitigation tactic?
How would that affect flexibility and possible bend radius ?

I honestly do believe we're making a mountain out of a mole hill here.
Big talk from someone whos good looking calfs alone are bigger than a mole hill.
 
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WizardStan

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How is situation 2 worse than situation 1? And situation 2 is basically a worst case scenario, at least some cables will never progress far enough to break the redundancy. So as near as I can tell, outside of a few extra cents for wider cables, the redundancy is strictly better: those that would have broken either get more usage or never notice that anything is wrong.
Because of this
Shouldn't the real question be is why the LCD cable wearing out in the first place?
That's the part that doesn't make sense to me. If the cable never breaks because of redundancy why does it matter? If it breaks six months later why does that prevent you from questioning why it's wearing out? Nothing is lost by adding the redundancy, only gained.I still don't see why redundancy isn't better. If there's a problem and they're going to break then they are going to break, and if an extra few pennies gets a few more months out of them then I figure that's money well spent, and if the redundancy actually prevents them from breaking at all then it's definitely money well spent.

Big talk from someone whos good looking calfs alone are bigger than a mole hill.
Oh you smooth talker you. :)
 

FBnil

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How would that affect flexibility and possible bend radius
https://www.quora.com/What-are-the-best-electrical-wires-those-with-fine-threads-or-those-with-thicker-threads?share=1

The resistance per unit length is inversely proportional to the cross section of the copper. So, as wire gets heavier (thicker) the resistance goes down. So thinner gauge wire has a higher resistance per unit length than thicker wire.  Stranded wire is used because it is much more pliable and flexible over it's length than solid wire and the more wire strands inside a wire bundle, the more flexible and stronger the wire is.
 
N

Nickie

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seriously that whole redundancy obsession is getting ridiculous..... we use redundancy in countless scenarios everywhere, and the only real reason to it is "shit happens" ,
every mecanical system is prone to wear and then failure, the LCD cable is located in a highly mobile area, therefore it is reasonnable to plan ahead , it's a case of the age old "better safe than sorry"
 

TrashyMG

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seriously that whole redundancy obsession is getting ridiculous..... we use redundancy in countless scenarios everywhere, and the only real reason to it is "shit happens" ,


every mecanical system is prone to wear and then failure, the LCD cable is located in a highly mobile area, therefore it is reasonnable to plan ahead , it's a case of the age old "better safe than sorry"
Well in the case of the Pandora LCD cables the original cables were breaking within a few months of use and there are still some signs of it breaking today even with a more durable cable. It's one thing to say "shit happens" and another to investigate why the "shit happens" and to plan ahead to prevent the shit from happening in the future devices.  
 
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comradekingu

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But what if I get shot in the LCD cable? What if i want to play pikmin with my last dying breath.

I've never tried pikmin, but that might be some kind of shit that i want to do there and then. And if it doesnt work, well at least I had a chance.

I HAD A CHANCE. DONT PURPLE ON ME NOW DAMMIT!
 
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thatgui

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That's the part that doesn't make sense to me. If the cable never breaks because of redundancy why does it matter? If it breaks six months later why does that prevent you from questioning why it's wearing out? Nothing is lost by adding the redundancy, only gained.


I still don't see why redundancy isn't better. If there's a problem and they're going to break then they are going to break, and if an extra few pennies gets a few more months out of them then I figure that's money well spent, and if the redundancy actually prevents them from breaking at all then it's definitely money well spent.
I guess I have a problem owning a device "knowing" (or at least heaving the impression) it has a design flaw in it, and instead of doing something to remove the cause only the symptoms are treated...

Oh you smooth talker you. :)
Are they actually good looking ? I'm interest in a strange way:blink:

The resistance per unit length is inversely proportional to the cross section of the copper. So, as wire gets heavier (thicker) the resistance goes down. So thinner gauge wire has a higher resistance per unit length than thicker wire.  Stranded wire is used because it is much more pliable and flexible over it's length than solid wire and the more wire strands inside a wire bundle, the more flexible and stronger the wire is.
Mind explaning the connection to my question a bit ?

But what if I get shot in the LCD cable? What if i want to play pikmin with my last dying breath.


I've never tried pikmin, but that might be some kind of shit that i want to do there and then. And if it doesnt work, well at least I had a chance.


I HAD A CHANCE. DONT PURPLE ON ME NOW DAMMIT!
So sad it had only two moths till retirement
 

pmprog

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I guess I have a problem owning a device "knowing" (or at least heaving the impression) it has a design flaw in it, and instead of doing something to remove the cause only the symptoms are treated...
The only way you'd prevent issues with the cable is to remove the hinge, and make it like the Nintendo 2DS. (or find a way to transmit signals contact-less, I guess)
If you want to keep the clamshell, you're going to have to accept that there is *always* going to be the possibility.
 
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Bosbeetle

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I guess I have a problem owning a device "knowing" (or at least heaving the impression) it has a design flaw in it, and instead of doing something to remove the cause only the symptoms are treated...
The only way you'd prevent issues with the cable is to remove the hinge, and make it like the Nintendo 2DS. (or find a way to transmit signals contact-less, I guess)

If you want to keep the clamshell, you're going to have to accept that there is *always* going to be the possibility.
Sadly the mipi cable option cannot work... However probably even such a cable would be under quite some repeptitive stress.
 

FBnil

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Mind explaning the connection to my question a bit ?
hmm.. I gotta stop posting too late... not sure myself what I wanted to point out.

Original question was "Is it possible that the traces on Pyra's cable can also be made thicker? Does that make any sense as an additional mitigation tactic?"

Note the words thicker, as opposed to wider.

From the article (and comments), thicker would make it less bendable, hence more metal fatigue, breaks earlier.

However, there are more variables, like the bendability of the plastic. Making a trace wider, still leads to rupture of the whole trace, but two thinner tracelines would make it impossible to patch (heh, as it is now, it is impossible to me). And I did not think of these.
 
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thatgui

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The only way you'd prevent issues with the cable is to remove the hinge, and make it like the Nintendo 2DS. (or find a way to transmit signals contact-less, I guess)

If you want to keep the clamshell, you're going to have to accept that there is *always* going to be the possibility.
Depending on how the hinge(s) will look like, routing the cable directly from the board to the screen could still be an option (much like IBM/Lenovo did it in the past)
 

WizardStan

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I guess I have a problem owning a device "knowing" (or at least heaving the impression) it has a design flaw in it, and instead of doing something to remove the cause only the symptoms are treated...
I've got some unfortunate news for you: everything you own has a flaw. Every product ever produced in mass quantities has a greater than zero failure rate. The best anyone can do is design around the flaws and hope for the best. There is not a product in your house that isn't a ticking timebomb with some (sometimes extremely low) probability that it will fail: electronics wear out; batteries inflate; oven safe glass spontaneously shatter when heated; Pandora cables break.
But ok, I understand where you're coming from, you don't like knowing that something has a flaw even when it does, so I will tell you with a straight face that the Pyra cable has no flaw, there's no need for redundancy, it's just there as a precaution to make the people who experienced the Pandora cable problems feel safer. And I'm actually serious about that, the original cable problems were identified, the failure rate in later Pandoras went from over 20% for just the cable down to below 5% for everything (I forget where I calcuated those numbers from, it was something ED said years ago about 6 months after the CC Pandoras started shipping, sorry). 5% is an amazing failure rate, big companies drool over less than 5% failure rate. If that 5% was all in the cable it would still be considered a problem solved by Nintendo and Sony. ED went a step further and proposed the redundancy "just in case", because 5% is still not 0% and he wants people to feel safe.

But even if that's not enough, even if you don't believe me or you want a guaranteed 0% failure rate and nothing less will do, you still haven't explained why that makes the redundancy is bad. Why does an extra 6 months of usage mean that you cannot also be worried about the cause of the breakage? Why is it so important that it break early rather than later (and in some cases not at all)? These are not mutually exclusive things, if there's a huge number of cables breaking after a year rather than 6 months it'll still push someone to question why, ED's not just going to keep throwing more cables at the problem. I still see the redundancy as strictly better.
 

Bosbeetle

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What the heck is a MIPI cable? :eek:
Oh sorry then I misinterpreted some of your earlier posts.

I got the impression from ealier posts that a non ribbon like LCD cable would be used but that it was switched later on. But I might just have misread it. Funny I cant seem to find it must have imagined it.
 
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Grench

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ED's rounded edge cable with redundant traces is an OK solution.

So - this brings the thought that some time the best way to draw consensus to an OK solution is to examine the alternatives and see how much worse they are than the proposed solution.

If the cable is going through the hinge, then it is going to need to curl through the hinge and flex and slide as the lid opens and closes.

Alternative bad option 1:  No cable.

In this option the lid hinge has contact wires that slide on pads on the top edge of the lower case.  Should work until the contacts get dirty, but since they're exposed, the user could blow them out with contact cleaner.  A disadvantage is that the exposed contacts could create micro-sparks and radio interference as the contacts slide against each other.  An advantage is that it could look very steam-punk, which is also a disadvantage.

Alternative bad option 2:  Flat exposed cable.

IBM & Lenovo have used this in many of their notebook computers.  The connector is a flat black ribbon cable ~40mm wide that comes up from a slot in the base and into a slot in the display frame.  The cable bends up to 180 degrees every time the unit is opened/closed.  The primary disadvantage is that this is an exposed cable - subject to wear and tear - and it's ugly on close inspection.

Alternative bad option 3:  Wireless with a clip on display.

Additional power needs to run transmitter would be substantial.  Display would get heavier as it would require it's own battery.  Potential for 2 Pyras to interfere with each other - see the display signal of the guy 3 rows up in the airplane.  Yet another radio.

So, ED has managed to greatly refine the flat curled cable through the hinge design.  He's probably changed hundreds of the original Pandora ones.  He knows where and how they fail and has come up with a refreshed design that he's confident in.  I'm willing to defer to his experience on this one.  He likely has the best possible solution already.
 

EvilDragon

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Well, an analyzation why Pandora cables fail would cost more than 10,000 EUR. It's not easy analyzing cables with such thin layers - and find out why exactly they break. That needs very high-tech equipment.

Of course, we got our own experiences from the units we got back.

A lot of them failed because they teared at one edge. That's why we're not using edges anymore (round them) and have less of them.

Also, a few times the cable simply wedged at the plastic until it hit the copper trace. Therefore, the traces of our cables are further away from the edge.

We also checked details of other cables (well-known and very robust 3M cables) and will use the same copper thickness they have - and they are know to be working well even when you fold them a lot. They're VERY robust.

And finally, if a trace breaks, we added redundancy... I guess that is the best we can do. No other options would work easily, sadly.
 

TrashyMG

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^ Great!, it looks like you got it well covered EvilDragon.
 

WizardStan

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Hey ED, are my numbers more or less correct? Going from a 20% failure rate originally to below 5% after making some changes for the CC and 1Ghz Pandoras? I can't remember how I know those numbers, they're just in my head and I'd like to be sure I'm not just making them up.
 
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