Jonathan said:...using an RFID encapsulated into a plastic credit card,
upon which I'd paste a picture for her.
To avoid going to the extra trouble of RFID you could glue
an iButton to each card, and fit a reader into the microwave.
If you want to talk about overkill how about the RFID chip that's implanted
into a person's arm? Either her that would turn off the appliances if she
got close or you two to turn them on. Probably you guys since you mentioned
she has the hyper-aware senses and would spot the device after it's placed
in her arm.
I'm sure if you google microwave repair, you'll see how doable it
is. When I read up on it umpteen years ago, it discussed all the
lockouts and the magnetron electronics. It's something simple like a
relay and/or MOSFET, HV cap, & HV diode. You'd just be turning the
magnetron on and off.
The point here is that she will focus on these and make our lives a real
pain over them. Whatever method we devise for a solution here needs to
be one where the technique for enabling the various systems can be
hidden in such a way that she will think it is entirely "MAGIC" that we
use. No technical gizmo can become the focus. For example, if we have
a toaster oven that we just seem to turn on and use normally without any
obvious special means that she can observe, she will struggle with it on
her own for a bit and eventually decide to simply hand us the food when
she wants it cooked that way. And that's fine, the way we want it. But
if she sees us use some "special device" or "special means" and she
makes the connection that this is either now missing (hidden) or else
needs a special technique to make it work, she may get frustrated and
angry. But not so, when all the pieces she sees are always there.
Yes. That is pretty good, I think. I don't know if I mentioned this before,
but one of the things I considered was using an RFID encapsulated into a plastic
credit card, upon which I'd paste a picture for her. She could grab that card
and wave it near the microwave and all the necessary particulars would be
automatically programmed in. This would be an optimal solution for the
microwave, as I'm sure she could handle the popcorn picture just fine. It would
allow me to program copies of the same card or also to program other cards for
other foods I might want to test her with, each with their own pictures. That
microwave idea isn't general enough for other power outlets, most of which I
don't want her using at all. But the microwave is something she is *almost*
able to handle, if only something like the card existed today.
The idea you mention above might work (room-wide basis.) I could see how if it
was too inconvenient. My gut tells me it would be trouble, though. I really
need the ability to experiment on a per-item basis with her, so that I can
tinker to get the whole picture right. An example would be that I shut off, by
default, too many things and that this causes her to stress out and wreck havoc
elsewhere in the middle of the night. Not being able to turn on the room lights
would be a specific example of this. I'd be able to anticipate some of this,
but really it would need to be convenient to change whatever the current
arrangement was.
Sorry about the delay. Was on a business trip.
Jon
OK Jon, I am seeing a bit more of your problem.
You mentioned experimenting with your daughter, one
appliance at a time, so lets look at the microwave oven.
Where I live in Sydney, people chuck out microwave
ovens and other household goods on to the footpath
rather than getting them repaired for scavengers like
me to pick them up. Some ovens are very easy to
repair. Some of the chuck outs still work fine. I have
a box load of spares from discarded ovens for my
existing working unit.
I was thinking for you and your daughter. find a
simple microwave oven with a mechanical timer.
The "turn the knob" for so many minutes type. If you
can't find one for free just buy an old one.
Now, you modify or replace the existing mechanical
timing mechanism with a timer for say 2 minutes maximum.
Or build- in, a 2 minute electronic timer in series with the
existing mechanical timer.
Terry Pinnell's site has heaps of timer circuit ideas.
Your daughter makes her pop corn in the night. Even
if there was nothing in the oven, the magnetron
would survive 2 minutes of abuse.
If you or your wife want more than two minutes just live
with the two minute maximum time and and hit the timer
again or put in your own secret over ride.
I know you were talking about cards but could your
daughter learn to use a modified oven like this?
Jonathan Kirwan said:Not sure how to respond to this. It doesn't sound serious. But just to
make
sure, on the assumption you might be and need a technical reason, we would
not
be able to allow her to select the timing and power that way. The plastic
card
+ RFID approach, with a picture attached, allows her to select from one or
two
different things and to intentionally turn on the microwave. Not
accidentally,
when she walks by. Not always the same way, when she walks by.
Of course, it's crazy for other reasons. Just thought I'd take it
seriously for
a moment, though.
My preference remains an AC adaptation, though, because it has a broader
application than just the microwave. But regarding the microwave, the
RFID/card
is probably the slickest for my needs.
Jon
Yes, actually. A modified oven may be very good, in fact. We've joked that a
microwave with ONLY a popcorn button and nothing more at all would probably help
a fair amount. The other problem we do have is that she likes to warm up bread
with cheese on it in the microwave and that should NOT have 2 minutes to it --
here, more like 30 seconds at most. This is why I'd probably use several of
those convenient "cards" I mentioned -- I'd put pictures of each common thing
she likes to make and work on making sure she makes the connection and uses them
for the purpose. I think she would go along with this, after she got the idea
okay.
There are times when she chooses to repeatedly run the microwave for a few
seconds, stops it, looks, starts it again, stops, looks, etc. I think she's
learned this habit the hard way -- from burning things up. I might like to
experiment with some kind of accumulation counter that would allow her UP TO 2
minutes of use before it just refuses to work anymore until I "clear it" for
her. This would tend to inhibit the more serious problems.
In the case of the microwave unit itself, it may actually be better for me to
tinker with the front panel system either as you describe or in some fashion to
allow me the flexibility for her use, with limitations as I later find I need.
(Rather than using a specialized AC power outlet, for example.) That may get
back to a programmable microcontroller or, at least, some manner of
programmability in it so that I can discover new problems and work out new
strategies to cope with them. (Hopefully, with an end in sight -- but if no
exact end, then at least some very long times before I have to come up with
something new.)
We are also finishing a self-contained area for her, occupying about 1400 sq ft
or so of pre-existing space in our home. I've already finished up a new kitchen
there and am working on a new bathroom. In total, she will have a bathroom, a
large den area (family room), a toy room with her computer and stuffed animals
and toys of various kinds, a bedroom, and a kitchen. Nearby, we will also have
two rooms for a caregiver that can "live in" with us and her, which add another
800 sq ft, for about 2200 sq ft separate from the rest of the house we live in,
with me and my wife and my youngest child (who is also autistic, but not so
seriously so.) Total space is about 5000 sq ft, so we aren't cramped.
Over time, I suppose, I'd like it if the modifications we do and work through
could find a broader market than just ourselves. If we can work out those
things which satisfy our own needs and yet are adaptable enough to adjust to the
needs of others without burdening the ideas down in the process, then that would
be nice. We've already contacted one of the construction folks we know who
specializes (and has long done so, some 30 years) in adapting homes. And he
believes that he'd be able to make immediate use of some of what we've talked
about. The state pays for some of these things, but will only pay for UL
approved adaptations, if electrical, so that would be a necessary hurdle.
Oh, well.
I've enjoyed having to write about this and think more about what it is that may
really be needed. It's helped me focus better, quite frankly. My thanks to you
and others.
Jon
The state pays
for some of these things, but will only pay for UL approved adaptations,
if electrical, so that would be a necessary hurdle.
I read in sci.electronics.design that Jonathan Kirwan
Does UL already have a special policy for this situation? If not, I
suggest you (and others) discuss the possibility with them.
But is there a reason to suspect that they'd set aside the necessary
testing in the case of a microwave modified for "special needs?"
Somehow, I think they would not do so.
All I can imagine is that they'd
require such microwave units to be even safer, should they know the use
to which they'd be put. (I believe the entire unit would need approval
as a whole, not just the control panel.)
Am I misunderstanding the question here?
In the case of the microwave unit itself, it may actually be better for
me to tinker with the front panel system either as you describe or in
some fashion to allow me the flexibility for her use, with limitations
as I later find I need.
Jonathan said:Just did a quick look and it is a "could be." Do you have a good site for
buying such things and what kind of price would this add to each card? (Keep in
mind that each card needs to be "very cheap" as they will be lost, tossed into
the garbage, etc. I'll need these things literally by the dozen.)
It's easiest to order direct from Maxim, but you can also get them
from Newark. DS1990 (ID only) is $4 in one-off, if you care to teach
the reader about every individual chip. Otherwise use DS1971 (EEPROM)
for $5.64 and you can store the "available functions" in the chip.
Maxim are good about samples. Get a probe socket (for example DS9092)
for each device that needs a reader. You'll need a adapter for your
PC to plug in to RS232, parallel port or USB, to program the buttons
and test the software. The plastic fobs (DS9093A) are what I use for
my sports scoring equipment - the runners wear an NVRAM button on an
elastic band around the wrist, but you could tie a picture card to them.
If you get samples from Maxim, and buy an MSP430-1121STK starter kit
and JTAG adapter from Olimex, you'll have a complete development
environment for US$35+shipping. Check though, I think the EEPROM
buttons might need 5V instead of the MSP430's 3V, which would require
a level shifter.
Jonathan said:An environmentally sealed RFID would be relatively maintenance-free
Fair point - but the IButton sockets are very shallow (easy to clean),
have large stainless-steel contact areas, and would probably work even
if filled with mashed banana. In my case the problem with grot is the
additional leakage current. In street orienteering the controls are
often chained around lamp-posts where dogs piss on them, which shoots
the <1uA average consumption out the window :-(. They need cleaning
if the CR2032 battery is to last the expected five years, but since
the units are potted, a bucket of soapy water and a toothbrush works
fine.
