Those that work in front of a computer for a living spend most of the time making very little sound. Unless you’re a member of the clicky mechanical keyboard club, your working time is a low-observables time during which people can forget about you. You can make sure you’re not overlooked with this smartphone hotspot presence detector.
[Emilio Ficara]’s quiet work habits resulted in his housemates locking him in sometimes, to his inconvenience. PIR or microwave occupancy sensors might have worked to fix the problem, except that a few flexing fingers aren’t always enough to trigger them. Luckily, [Emilio] is also wisely distrustful of free WiFi, so his phone is always set up as a mobile hotspot, giving him the means to reliably detect his presence. An ATtiny2313 and an ESP-01 do the business of polling for the SSID of his phone and blinking a bright blue LED by his door for his housemates. It’s not perfect, of course; it could easily be spoofed by anyone else who knows his SSID. But simple works for now.
With almost everyone carrying one now, smartphone detection is a good proxy for the presence of a person. But it doesn’t work in every case, so you may want to familiarize yourself with the aforementioned PIR and microwave methods.
For most of us, a memory lapse is as harmless as forgetting to bring the garbage to the curb, or maybe as expensive as leaving a cell phone and cup of coffee on the roof of the car before driving off. But when the toddler sleeping peacefully in the car seat slips your mind in the parking lot, the results can be deadly.
We have no doubt that child detection systems will soon be standard equipment on cars, like backup cameras and trunk-escape levers are now. Not willing to wait, [ayavilevich] came up with his own car occupancy sensor for child seats (Update: We originally linked to the Instructable but [ayavilevich] wrote in and mentioned this is actual Hackaday Prize entry and he’s looking for more people to get involved in the project).
Dubbed Fochica, for “Forgotten Child in Car Alert,” the system is clearly a proof of concept right now, but it has potential. The Arduino Uno senses Junior’s presence in the car seat with a homebrew capacitive sensor under the padding of the seat and a magnetic reed switch in the chest harness buckle. An Android app on a smartphone pairs with a BLE module to get the sensors’ status, and when the phone goes out of Bluetooth range while the seat is occupied, the app sounds an alarm. Simple, but effective.
We like how well [ayavilevich] thought this through. Systems like this are best left uncomplicated, so any improvements he makes should probably concentrate on engineering a reliable, fieldable device. Another hack we’ve presented in the kid-safety space is fast stairwell lights for a visually impaired girl, which might provide some ideas.
Continue reading “Smart Child Seat Aims to Prevent Tragedy”
In a lot of ways, portable toilets are superior to standard indoor-plumbing-style toilets. This is mostly due to the fact that they have a status indicator on the door. It’s a shame that no indoor bathrooms have figured this out yet, especially in office buildings where your awkward coworkers bang on every door rather than just check for feet in the huge gap that for some reason exists between the floor and the stall door. Anyway, [Chris] and [Daniel] came up with a solution for this issue, which also eliminates wait time for bathrooms in their office.
Their system is an automated bathroom status indicator that reports information about the bathroom’s use over WiFi. Since the bathrooms at their facility are spread out, it was helpful to be able to look up which bathroom would be free at any given moment. Several Raspberry Pis form the nerves of the project. Custom sensors were attached to a variety of different door locks to detect status. Each Pi reports back over WiFi. This accomplishes their goal of being subtle and simple. They also point out that they had to write very little code for this project since there are so many Unix and embedded hardware tools available to them. Checking the status of the bathroom can be as simple as running netcat.
If you’re looking to roll out your own bathroom status monitor solution, [Chris] and [Daniel] have made their code available on GitHub. There are a number of other ways to automate your bathroom, too, like switching the exhaust fan on when it gets too smelly or humid, or even creating a device that dispenses your toilet paper for you.