[Arm-netbook] Warning about tablets/netbooks with detachable keyboards

[chadvellacott at sasktel.net]

On 16.12.14 13:20, Luke Kenneth Casson Leighton wrote:
> On 12/13/16, dumblob <dumblob at gmail.com> wrote:
>> Hi Luke,
>>

>> In case you're planning to have the keyboard detachable (even worse if this
>> detachable piece should have some connectors like USB), think of it twice
>> as per experience of many users of different such tablets/netbooks (youtube
>> is full of such reviews), the detachable connection is very fragile
>> (because the detachable design requires a shallow or rather just "touching"
>> connection in contrast to "sliding" deeper connectors like USB).
>
>   ok.  first thing: have you heard of the alwaysinnovating touchbook?
> it was the world's very first hybrid netbook / tablet.  most people
> don't even know it exists, sadly.  as a monolithic design it would
> ordinarily have a lifespan of about... six to eight months, but
> because it was targetted at linux users that was actually
> about...eighteen months / two years.  what killed it was the use of a
> 720mhz ARM Cortex A8, RAM limited to 512mb... no means of upgrading
> except a whopping $50k for replacing the entire main PCB.
>
>   anyway: the casework was extremely robust, with the
> keyboard+extra-battery portion having inch-long "arms" at the sides to
> securely and firmly hold the main tablet part in place... in a
> standard USB socket.

    The "ThinkPad"-series had (or has) convertibles ("X41 Tablet", "X60 Tablet, 
Helix) [1].
    (By the way, the X60-convertible is listed as supported by "libreboot" [2].)
    This line of computers seems to have been distinctively-sturdy.  And the 
X60-convertible was said to have "signature ~ bulletproof build quality" and be 
"more ~ sturdy than any ultralight convertible we have used." [3].
    So maybe how they JOINed the key-board to the screen, was more sturdy than 
other often-problematic "implementations".  (But I have neither seen nor read HOW 
Lenovo connected the two parts.)
    As far as I see, there are two separate concerns- (1) the data-connection (USB 
here, I guess Luke wrote) (the concern of the original post), and (2) how the 
screen and the key-board are held (joined) together (a 2nd thing discussed in this 
context, like the arms mentioned above).

    [1] https://en.wikipedia.org/wiki/ThinkPad_X_Series
if you press ctrl f and look for "conver"
    [2] https://libreboot.org/docs/hcl/index.html#supported_laptops_x86intel
    [3] http://www.laptopmag.com/reviews/laptops/lenovo-thinkpad-x60-tablet
>
>   you have to bear in mind that i'm being quite realistic about this
> whole exercise: if i can't design it to be robust in PLA with a
> standard mendel 3D printer, and i can't get off-the-shelf generic
> parts that are commonly available from multiple suppliers in huaqiang
> rd, futian district, shenzhen, china, it ain't going in.
>
>   so whilst what you're seeing is complaints based on a
> fight-to-the-minimum (in terms of both thickness and price), i will be
> designing stuff that's "chunky", realistically maintainable by a
> lego-mindsetted individual, and built to last.
>
>   therefore, i will *NOT* be attempting to replicate the existing slew
> of magnetic catches and so on, apart from anything i won't be able to
> get hold of them as they will have been custom-designed for specific
> OEMs.
>
>   i _do_ have a background in physics and mathematics which gives me
> some mechanical design aptitude :)