[Tfug] Tablets

[Bexley Hall]

Hi,

I need The Straight Dope on tablet offerings.

I have three locations in the house where a user can interact
with its automation via kiosk-like stations.  These are located
just inside the front and rear entryways -- as well as the
hallway to the bedrooms.

The bedroom hall is considered "private space" vs. the more
"public space" that the front and rear entryways represent.
I.e., you don't expect visitors to wander down there.

OTOH, the entryways are *very* "public".  So, whatever is located
there is very visible.  As such, the "kiosks" in these locations
should be as unobtrusive as possible.  I.e., you wouldn't want
to draw *extra* attention to them due to size, prominence, etc.
(e.g., you wouldn't set up your *workstation* in your living room!)

Also, *at* an entryway, a user is typically arriving or departing.
So, the types of interaction with the kiosk tend to be "summary"
and "abbreviated" -- verifying everything is "correct" prior to
entering or exiting the building.

By contrast, any prolonged interaction would likely occur in the
more "private" hallway location (or, *seated* somewhere using a
laptop or desktop PC, etc.).  So, that kiosk/terminal wants to
be "friendlier" -- more hospitable.  And, can risk being more
obtrusive because it is located off the beaten path (as far as
visitors are concerned).

(N.B.  The hall kiosk also serves similar roles to the entry
kiosks regarding "arrival"/"departure" -- except pertaining to
"arising"/"retiring"... from the bedrooms!)

I was hoping to use COTS devices to fill these roles.  E.g.,
a pair of "tablets" for the front and rear entryways -- and
a larger tablet for the hall unit.  But, getting a *large*
device (for the hall) seems problematic.  So, I will probably
just use a more conventional "touch computer" packaged in a
slim frame. (I currently have a 15" device that might fit the
bill)

[Sorry for the long winded introduction  :< ]

For cosmetic reasons (remember, this is a *house*, not a
commercial office space!), the tablets at front and rear
entryways will have to be capable of operating off of their
respective PoE drops (I would prefer to avoid PoE+).  I'm
not keen on having a power cord running down the wall to a
regular electric outlet nearby!  So, nominally 10 or 12 Watts
(I can allocate that to whatever supply voltages the tablets
require -- within reason).

[The hall kiosk won't fit in this power budget mainly due to
the size of the display.  So, I am having to resort to providing
mains power at the kiosk.  Doing so in a cosmetically pleasing
way is a royal PITA! <frown> ]

Ideally, I would like to find tablets that I could root since
running an application *under* some (lame) OS will obviously
impact performance, etc.  (I need to be able to run full motion
video over the network interface in addition to the interactive
aspects of the interface *and* don't want a user to have to
do anything to "boot" the application -- nor risk some other
application co-opting or crashing the device: "Your battery
level is 12%.  Please recharge, now."  "WiFi network detected.
Do you want to connect?"  "A system error has been detected."
etc.).

(Hardware) Requirements:

- Low operating power (including any increased power that it would
  tend to want to require to keep its battery topped off)
- Can't require pens/styli -- fingers only!  No need for multitouch.
  Touch technology may be significant as you can't count on the user
  having a *bare* finger in those two locations!
- I can't see a real need for a rear facing camera as it would
  just be staring at the wall!  :>  OTOH, a front facing camera
  opens possibilities for future authentication mechanisms!
- Microphone (or audio in) and speaker (or audio out) would 
  probably come in handy, though!
- A *wired* network interface essential -- though it may need to
  be implemented with an external adapter or via a USB interface
  (boo-hiss!)
- Bluetooth is unnecessary (and would need to be disable-able, if
  present as I'll have my own BT radios nearby and don't want to
  have to compete for spectrum).
- WiFi is completely unimportant (and similar issues to BT)
- Accelerometer would only find use if we were expecting earthquakes
  (since the thing will be bolted to the *wall*!)
- The most taxing (computationally) activity would be playing streamed
  video -- though I can design a CODEC to trade horsepower for bandwidth
  and/or fidelity.

Questions:

- What sort of offerings will fit the ~12W power requirements?
  Note that the device has to assume it will be on 24/7/365
  so I can't "cheat" and slowly recharge it's internal battery
  between "sessions" -- though I can obviously scale down the
  device's activity for much of the time (e.g., displaying a largely
  static screen, etc.) as *active* duty cycle will tend to be very low.
- What's the largest *practical* (i.e., something I can afford to
  keep a spare or two) display I can find? (i.e., hoping I might
  be able to go COTS for the hall kiosk as well)
- Suggestions as to vendors?  Models?  Is the dealextreme sort of
  offering even worth attention?  (keeping in mind I am NOT looking
  for "mainstream application compatibility"!)
- What sorts of reliability can I expect?  (note that these are
  now filling "infrastructure" roles -- not the sorts of things you
  *plan* on replacing regularly.  How often do you replace your
  *thermostat*?)
- What might I have forgotten to consider? ? ?

Aside from /Spark/, there don't appear to be any prospects that look
really encouraging (and I don't hold out hope that /Spark/ will
actually materialize).  Given my modest hardware requirements, is
it better to just roll my own (rather than fight with the inevitable
"undocumented" aspects of COTS offerings and "half-ports"?) -- and
modify the implementation of the hall kiosk to make it adaptable to
the front and rear entryways (I think I have some 9" panels that
I could probably use that might fit in the PoE power budget -- a bit
larger than I had intended, but...)?

Thanks!
--don