Experiment: Improving the keyboard quality, based on technique used in HP 200LX keyboard


hmc

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Hi guys,


today I got an idea, and I made experiments, and they seem to lead to somewhere :)


I try to improve the keyboard quality of the Pandora, using parts from a HP 200LX Palmtop's keyboard.


Issue:


The keyboard of the Pandora is much less suitable for quick writing with more than one finger. It's perfect for thumb-typing, when holding the Pandora in two hands, but if the Pandora sits on a table, and I want to type on it like on a laptop, I have a hard time.


On the HP Palmtop 200LX, though, I could write even much faster than on a standard PC keyboard. That keyboard was excellent.


What's the difference between the two keyboards?


It's hard to describe. This is my attempt:


- The Pandora's keys need to be depressed much more (way in vertical direction is larger)


- The Pandora's keys need to be pressed harder all the way down


- The Pandora's keys have a more squashy tactile feedback


This is the HP 200LX:


hp200lx.gif



Experiment:


Since I service the 200LX for about 15 years now, I know exactly, how it is built.


Today I had the idea to merge the keyboard "mechanics" of the 200LX with the Panodra's keyboard, in order


- to reduce the vertical way the keys of the Pandora need to travel, until the keypress is recognized,


- to lower the force needed to depress the keys


- to give each key a more defined tactile feedback


The method needs to be refined, and I hope that you can provide some more ideas and knowledge to that, but once I have a well working solution, we may try to bring some of the results also to mass production. At least for Pandora 2, but maybe even earlier.


The 200LX's keyboard is built this way (bottom to top):


It has the key contacts at the bottom, similar to the Pandora.


Then there is a plastic foil with holes in it for each key. It's a spacer for:


The next foil. This one has "bubbles" in it, one for each key. Each bubble has some graphite inside for the key contact.


Then there are the keys, mounted in a grid. Each key has a thin plastic pin, that is placed directly over a bubble.


See this picture (right to left is bottom to top):


02030073.jpg



More detail:


"Bubble foil" bottom:


IMG_2697.jpg


"Bubble foil" top:


IMG_2698.jpg


Key grid bottom:


IMG_2696.jpg


Key grid with fitted bubble foil:


IMG_2699.jpg


Keyboard top view:


IMG_2692.jpg


What I did:


IMG_2687.jpg


IMG_2688.jpg


IMG_2700.jpg


- I cut a row of the bubble foil and fitted it - with the spacer foil in between - onto the key contacts of the Pandora, so that the keys "Q" and "W" were modified.


- Then I fitted the Pandora key mat onto that and tried to press the two mofidied keys.


Result: The keys now have two pressure points, the first one when the Pandora key rubber releases its resistance, and the second when the bubble releases its resistance. Not so good.


- Then I applied small pieces of double-sided adhesive tape onto the bubbles, that I used to attach very small pieces of plastic on top of each bubble, bridging the gap between the bubble top and the Pandora key bottom, in the hope that the Pandora key would directly apply its force onto the bubble and that the result would feel similarly to the 200LX keys.


Result: After adjusting the thickness of the attached plastic parts to about 0.5mm (0.3mm was too thin, 0.8mm was too thick), the key press was now indeed directly applied to the bubble. However, now the mechanical resistance of both the bubble and the Pandora key mat's rubber "mechanics" summed up, making the key even harder to press. The tactile feedback was also not optimal yet.


- Then I cut out one key out of the key mat of the Pandora, placing it directly onto the bubble. I hoped that this would avoid the summed up mechanical resistance and make it easier to press the key. It did. However, the tactile feedback was still not good.


IMG_2691.jpg


- Analyzing the key I just cut out, squeezing it between my fingers, pressing onto that little thing on the bottom, that originally establishes the key contact when the key is pressed, I found that the entire key, even the inside, is made from elastic rubber, and that makes for a very weak pressure point in combination with that bubble.


Bottom line:


In order to improve the Pandora's keyboard in a way that it feels more similar to a HP 200LX keyboard, we'd need the following:


- A bubble foil that fits the key layout of the Pandora. Does anyone know a source for something like that? Costs? Pandora 1.


- A modified key mat for the Pandora (costs?), with the following differences to the current one:

  • A harder key, not made from soft rubber, but rather stiff plastic
  • A well fitted bottom thing for each key (I don't know how to call it, you know, that knob on the bottom, that establishes the contact normally), which should have a smaller diameter than the current one (otherwise the bubble does not provide that snappy tactile feedback) and which needs to be placed directly above the bubble, with almost no gap in between.


Maybe, if there are enough people interested in such modifications (I have a lot of former 200LX users in mind, that are hesitant about the Pandora mainly because of the keyboard), these modifications could be financed even for Pandora 1 already, using crowd funding.


Thoughts?


Opinions?


Questions?


Thank you!


Daniel
 
I love seeing hardware hacks like this, makes me envious since I have little free time.


Looks like Project 3 (iCP2?) which design may lead to Pandora 2 appears to hae a bubble foil layer, one can guess a better keyboard? but the keys haven't been shown yet..
 
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Great, then you already have a supplier for such bubble foil? How about a few samples for the Pandora, so we can play with them and optimize them? :)


EDIT:


Is the concept for Pandora2 keyboard finished already? How will the keys be built?
 
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Issue:


The keyboard of the Pandora is much less suitable for quick writing with more than one finger. It's perfect for thumb-typing, when holding the Pandora in two hands, but if the Pandora sits on a table, and I want to type on it like on a laptop, I have a hard time.


On the HP Palmtop 200LX, though, I could write even much faster than on a standard PC keyboard. That keyboard was excellent.

I think the Pandora will probably be in people's hands more often than on a table when they type. Don't you agree?


Also, do you think most people that can type on a standard PC keyboard properly (no hunting and pecking) will be able to type faster with their thumbs (or forefingers) or all ten fingers?

The design and layout is different:


parts2.jpg

Yikes! My thumbs are crying at the smaller keys! :( Sorry, I don't find this appealing, it looks like a sacrifice to reduce size.
 
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Yikes! My thumbs are crying at the smaller keys! :( Sorry, I don't find this appealing, it looks like a sacrifice to reduce size.
That's what the naysayers said about the first Pandora as well, and I quite enjoy thumb typing on it. It does indeed seem smaller, I have my doubts about the rectangular keys, but I'm willing to give it the benefit of the doubt.
 
That's what the naysayers said about the first Pandora as well, and I quite enjoy thumb typing on it. It does indeed seem smaller, I have my doubts about the rectangular keys, but I'm willing to give it the benefit of the doubt.
Fair point, but I don't like typing on the P1 numerical keys which appear to be about the same size as what Craig presented. I mean, certainly there's a lower bound on size...
 
Without having tried all this (obviously), I must chip in with this: hmc is absolutely right in that the HP 200lx keyboard is easier to type on (be it with thumbs or with more fingers). And that is including the facts that the keys themselves are smaller. So, if these changes bring the keyboard feel closer to that of the -lx, it is indeed an improvement.


By this, I don't mean that I am disappointed with the pandora keyboard - It is quite good enough - but if it was a competition for keyboard feel alone, the HP wins over the Pandora (and possibly the Psion5 wins over them all).


Also: Great experiments, hmc!
 
Craigix,


the image of Pandora2 keyboard looks great! It seems to me like a big improvement to the current keyboard, which is, agreeing to what Moxie said, not bad, but it could be even better, especially for fast typing when sitting on a table.


bismuthdrummer,

1 - I think the Pandora will probably be in people's hands more often than on a table when they type. Don't you agree?


2 - Also, do you think most people that can type on a standard PC keyboard properly (no hunting and pecking) will be able to type faster with their thumbs (or forefingers) or all ten fingers?


3 - Yikes! My thumbs are crying at the smaller keys! :( Sorry, I don't find this appealing, it looks like a sacrifice to reduce size.

1: Probably you are right, but I don#t think that thumb-typing will be harder on such a new keyboard.


2: Not all ten fingers, but from my experience, and what I heard from many 200LX users, people, when typing fast on a 200LX keyboard, use about 6 or maybe 8 fingers. I used 8 fingers all those years. And I could type really, really fast on that keyboard :) The small size is actually an advantage: Fingers don't need to travel as much as on a larger keyboard, so it's actually easier, once you got used to the Keyboard, to type quickly. Provided that your fingers aren't too think of course.


3: What looks very promising is the 4th row of keys! Less Fn- combinations needed? As said already, I don#t think that tumb-typing will be harder with that new keyboard. Well, it may depend a bit, on how the keys themselves are built.


Craigix, do you have an image of the key mat? How will the keys be built?


Would it be possible to have two different key mats? One with convex rubber-based keys, like the current ones, for better thumb-typing, and one with flat and harder keys for those, who prefer to "laptop-type" on the Pandora?


I didn't follow all the Pandora2 discussions, but maybe I should! :) When will the first prototype of Pandora2 be built? I need to test this! :)


Here are a few examples of keyboards I tested, and my experiences with them.


(all pictures not by me, but linked from online sources)


200LX as described in first post: Excellent!


HP200LX_SG70200118_small.gif



Viliv N5 UMPC:


- Looks very good at first, but has its disadvantages: Fast typing is difficult, becasue the keys are all so uniform, and there is almost no gap between the keys. Ithappens often, that you hit the wrong key accidentally, when typing quickly. Otherwise the keyboard is quite good.


--> A gap between keys is essential! Keys may be small then (like on the 200LX), but that's perfectly okay.


vilivn5-1024x768.jpg



Trust 17808 Bluetooth keyboard:


- The keys have almost no spaces in between, BUT: Each key has an elevated part of it, that is smaller than the actual key, So the fingers again feel gaps between the keys, and that makes quick typing possible. Quite good keyboard, but it is too large. It's 20cm wide.


17806-4.jpg



Sharp Zaurus SL-C1000, SL-C3x00:


Very small device with very flat keybaord, keys have a very small vertical way when pressed, and only little force is needed for pressing them. That's why it took some time to get used to the keyboard (coming fro the 200LX), but after all, I could type on that one almost as quickly as on the 200LX.


Good keyboard! And it was build similar (internally) as Pandora 2 pictures by Craigix show. That makes me hope the best for Pandora 2. :)


zaurus-c3000.jpg



Daniel
 
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Has it been answered already why the actionkeys are on the left and the dpad on the right?
 
Probably because the plate is upside down, i.e. you are seeing the underside of it.
 
I don't think it is upside down as the enter key is in the downright corner.
 
I don't think it is upside down as the enter key is in the downright corner.
Look at the top of the picture. There is another key, symetrical to the enter button opposite it. Shift perhaps?
 
I second what Moxie said: While the Pandora's keyboard is surprisingly good the Psion 5 is outstanding and only slightly wider (about 16 cm).


When I was asked just yesterday why I do carry my Pandora AND my Psion 5 mx Pro I had to admit that the Pandora lacks some features which the Psion has. Mainly the excellent keyboard and some inbuilt programs (data, agenda...)


A2000
 
Off topic:


A2000, you may check my new Pandora port "PortaBase", if you need a database on the Pandora. (I assume that this is what "data" on the Psion is).


http://repo.openpandora.org/?page=detail&app=PortaBase-hmc


For an agenda replacement, I am currently working on a port of KDEPIM/PI by Lutz Rogowski to the Pandora (an excellent PIM suite!). However, I need his help for that, and he is very busy, so that can take quite some time.


Danie
 
I think the Pandora will probably be in people's hands more often than on a table when they type. Don't you agree?


Also, do you think most people that can type on a standard PC keyboard properly (no hunting and pecking) will be able to type faster with their thumbs (or forefingers) or all ten fingers?

The design and layout is different:


parts2.jpg

Yikes! My thumbs are crying at the smaller keys! :( Sorry, I don't find this appealing, it looks like a sacrifice to reduce size.

Looking at that picture and assuming the nubs and dpad are the same:


The new Pandora would be a little bigger (W x L) than the size of the current LCD.


I estimate that keyboard cover is around ~104mm x ~55mm (W x L) leaving the extra 5mm or so for the hinge solution.


Its a smaller Pandora with the same sized screen.


Tiny keys for sure as the four rows are almost the same height as the dpad.
 
Although never used the Pandora yet, the keys do look like they would need quite a deep press, where I'd prefer a lighter touch I think...


The smaller k/board on this one looks better IMO though, more like the change when newer Android version came out [forget which version now] and their one got more compressed to the lower section of screen.

25qunmg.png
 
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