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How Can I Build a Portable "Dead-Man's" Switch?
An anonymous reader asks: "I'm a widower caring for my very disabled child. I have family who check in on me often, but not reliably, and not every day. How can I rig up a 'dead-man's switch' that will alert family or emergency services should something happen to me, so that my child can be cared for? Her medical needs are significant enough that being alone for even an hour could be fatal for her. We do occasionally get out of the house, so a GPS type cellphone and a heart-rate monitor watch would seem to be the ticket, but how to link the two and get the desired dialing behaviour?"
There's this bluetooth enabled Alive Heart Monitor that apparently works with GPS, and with a PDA/smartphone or a server. You'd probably need to write (or hire someone to write) an application to use the data for the actual contacting other people in case of x part, but the hardware seems to exist for what you want to do.
Have you considered a medic alert bracelet for the times when you're out? Or are you in remote, non-populated areas?
May I suggest you visit a medical store? Get a device like those made for hospitals or old folks. Probably easier than posting to slashdot.
Being disabled and prone to dangerous falls myself, I know this sentiment all to well. Needless to say, I've had difficulty finding something that would not only work within my home, but anywhere I go, without needing to carry a full-blown cell-phone.
Something like a human-based form of OnStar, but with a heart/lung monitor and an accelerometer/impact sensor (to detect the speed and severity of a fall).
8==8 Bones 8==8
My aunt uses a device which is medically implanted by her heart. If her heart stops is defibs and logs a report. The same device can be modified to make a phone call and pass along GPS coordinates. Problem is, this requires surgery so it is not a DIY project. It is a nice solution though and water proof too. Talk to your doctor.
-Tim Louden
I saw an interesting article in a Japanese newspaper, it relies upon a relatively unique cultural circumstance, but I think you'll be inspired to think of how it can be adapted. The device was invented for one guy's family, but after it got some writeups in the newspapers, the idea was so popular that it went into production, and now lots of people have them.
There are many elderly Japanese people who live alone, some are deaf and can't use the phone, etc. so it's hard to get a way to check in on them to see if they're still alive. But almost every home has a hot-pot, an insulated pot with an electric heater used to keep water near the boiling point, to make tea every day. So some clever guy put a sensor in the hot-pot, if nobody picks it up within a day, it phones a preprogrammed number to alert someone to check in on them. Yeah, these people drink a lot of tea, it was the only thing they could think of that elderly people did EVERY day.
Of course this only checks in once a day, but you could probably think of other ways to adapt this idea.
This is not everything, but this type of phone might help-
e r?item=phoneFirst&action=viewPhoneDetail&selectedP honeId=2060
It is normally meant for kids, but it has reduced number of buttons, and a dedicated emergency button...
http://www.verizonwireless.com/b2c/store/controll
from the site-
Migo from Verizon Wireless is a kid-friendly wireless phone that lets parents and kids stay in touch. It's fun for them, and added peace of mind for you. The Migo phone has a simplified keypad that allows you to program in 4 numbers, an incredible speakerphone and a dedicated emergency key. And with Chaperonesm, you can use your handset or PC to locate your child's Migo. This is the perfect phone to keep kids and parents connected.
Note: I have no interests / investments / work relationship with verizon wireless.
Your case seems too severe for this solution, and I DO NOT recommend you use it. Seek professional services and equipment.
You could create a dead-man's switch using a computer with a voice modem and a GPS enabled cell phone. First, determine the longest amount of time the child could survive on her own. For my example I will use 18 hours.
On the computer, you set a 12 hour countdown. At any time, you can reset the countdown. If you are going to jump in the shower, just reset it. Whenever the countdown reaches zero, the computer would produce an audible alarm.
If the audible alarm is not acknowledged in something like 15 minutes, the computer sends a SMS or e-mail message to the cell phone. To acknowledge the message, just reply to the sender. That would reset the countdown.
If the message to the cell phone is not acknowledged in an hour, the computer can lookup the GPS information on-line, determine if the phone was moving, call friends, neighbors, family, or even 911. You can use the voice modem to convert text to speech to broadcast a message and even the GPS coordinates to whoever the computer called.
Note: If the computer is used to dial 911, make sure the emergency response center knows that you have automated a message and will be providing GPS information.
Friends, lots of them.
Seriously.
If you have this load as a caregiver, just having people around, helping and having someone to kvetch with is not just a good idea, but critical, if only for your own emotional health.
There are other people in the same boat, so perhaps finding or forming a community might be the way to go. Something less collective then a commune, but a structure like http://www.bruderhof.com/ (if christian). Equivalent communities exist in other religious traditions, as well as the religious (monks, nuns and others)associated with a belief structure.
Technolocial measures sound neat, but they have so many points of failure compounded by the people that have to be around to insure that they don't fail, that I would be suspicious of the lot. Not that I feel that way, but I would adopt that attitude by policy.
Consider the call clearing center that an alarm panel calls into: the UL standard calls for redundant systems that fail safe, two levels of backup power generation, duplicated sites, alarm receivers that fail busy so calls can get through, requirement for manual control, full data logging, crisis triage, etc.
A full technology solution is suspect, a hybrid system is probably better, and you have the adventure of searching out the real players from the fakes. Look to the service providers that a hospital might use.
And look carefully at response time: under disaster conditions it probably will swing out past your hour requirement.
Oh, you have to concern yourself with the other side: Are your critical systems on backup power? UPS and autostart generators? Tested each week?
There is a very good reason why the backup batteries in the telcos are usually glass lined lead-acid submarine batteries that (usually) power diesel boats. I don't think the cable co's are quite there yet. Just a guess.
Feel free to email me if required - there are a lot of details I don't know, and a phone call might be needed.
Don't be afraid of the complexity, a few minutes with some brainstorming buddies can cut that down to size. The legwork is a different story!
Best of luck!
This is progress?