[Anders] tipped us off about his hack that re-purposes a smoke alarm as a burglar alarm. Unfortunately, he came home in the middle of a burglary but wanted to be ready the next time someone tries to break in. By cleverly patching into the test button on an old smoke detector he created a circuit-trip alarm. One side of each piece of wire is secured to the frame and jam of a window. A paper clip completes the circuit by pinching the two bare conductors. If the window is opened the connection is lost and the alarm sounds.
We see a few problems with this system. First off, never hack your ONLY smoke detector, you are putting lives at risk by doing so. But [Anders] says he’ll have a replacement detector and since these things need to be replace every ten years or so, chances are you can find an old one kicking around. We’d recommend disguising the case so that people aren’t confused about it being a smoke detector. Secondly, he’s mounted the alarm right in the window frame so most likely an invader will just smash the thing to bits.
Anyway, it’s still an interesting reuse of these ubiquitous, and life-saving, devices.
[Tom Lee] and his colleagues of Sunlight Labs just moved to a new office. The doors are setup like a security checkpoint with electronic strikes and buttons on the inside to allow entry. The button simply completes a low-voltage circuit, activating the strike which made it quite easy to patch into. They build an interface board with a small relay to complete that circuit. As we’ve seen before, Linksys routers have plenty of extra room in the case so there was no problem housing the new circuit in this tiny network device. Now [Nicko] and his friends can use a custom app to input an access code or to verify a device ID from a cell phone and gain entry. The door still has keyed locks in case of a power outage. In fact, the only change made to the system was the addition of two wires to the “door release” button as seen above. See the one-touch device ID authentication in the video after the break.
This hack is similar to the GSM door entry from last year. In this case, the phones are communicating with the door via web interface and not the GSM network.
Will O’Brien at Biobug.org has been doing some cellphone integration work. He recently picked up some Motorola c168i cellphones from eBay. It turns out there is a serial port that uses TTL communication with a standard head-phone jack as an interface. [Will] soldered up a connector and used a USB to FTDI cable to interface with the phone. To his surprise he was able to read off the stored text messages even though they were PIN protected in the phone’s operating system. The messages on these units were trivial but this is another example of the importance of clearing your data before discarding your devices.
What if you could point your cellphone’s camera at someone’s face, and then know that person’s name, schedule, profile, and latest tweets? That’s the promise of Recognizr, an Android app prototype using a 3D model to recognize facial features, find a match on its server, and then superimpose that person’s social networking preferences around his or her face.
Created by Swedish mobile software designers The Astonishing Tribe, it’s astonishing indeed. Problem is, unless everyone opts into this service, it won’t be particularly useful. However, if it were ubiquitous, imagine how easy it would be to act like you’re using your cellphone, but actually be finding out that person’s name standing in front of you — while you snoop around her Facebook profile.
Finally, Facebook stalking finds its way to meatspace! On a smaller scale, this could be useful at, say, a trade show or a party. Electronic nametags would be lots of fun, if everyone would submit to them.
Apple has not made it easy to let the iphone communicate with external devices. Basically, you need a jailbroken phone to do anything. This post covers the current state of serial communication on the iphone.
A succesful example of making an application that uses the serialport on the iphone is xGPS, which let you connect to an external GPS.
Now that the protocol for basic communication with the TI chronos ez430 has been worked out (see previous posts) I needed to work on something useful. So I set out to try and control my wireless light switch with the watch. Sadly the RF receiver supplied with the chronos does not use a protocol which is likely to ever be compatible with the arduino so this example requires a computer.
So the story goes like this, my roommate needed to tap some IP phones for diagnostic purposes. I found a netgear HUB that would serve that purpose. This was not ideal as the IP phone needed power from the network, or a 48V wall-wart. He asked if I could get PoE to pass through the hub. Easy, I’ll just loop the unused pair and viola! Wrong.
What really happened is I had to do a lot of reading, and found a few key things. According to 802.3 af standards, the PSE or Power Supply Equipment, decides how power is going to be sent, while the PD or Powered Device has to accept BOTH modes.
This might be a good time to explain that 802.3af can send power one of two ways. Using phantom power through pins 1,2,3 and 6 (mode A) or through the unused pairs, pins 4,5,7 and 8 (mode B). In all my testing, Cisco favors mode A power. Probably something about gigglebit standards?
[Kajer] was doing some work with IP phones that use Power over Ethernet. While trying to get this to work with a network switch he decided to use PoE to power the switch itself. The best thing about this is he managed to shoehorn all of the necessary bits into the stock case. Those bits include a bridge rectifier, transistor, resistor, and a 5v power supply. Along the way he discovered he can now power the switch off of USB if he wishes.
How about a DIY electric car, with one of these Trexa EV platforms and start build your own electric car! Trexa is gunning to be the first electric vehicle devlopment platform, with a battery, driveline and power electronics built-in.
The Trexa platform offers an unprecedented level of versatility because it contains an entire vehicle’s drivetrain within one low-profile enclosed structure. The platform is highly scalable, so features such as range, suspension, torque, acceleration, and top speed can all be tailored to suit the vehicle’s intended purpose. For starters, the standard platform has an acceleration of 0-60mph in 8 sec, a top speed of 100mph, a 105 mile range, and a charge time of 4 hours (based upon an efficiency of 200Wh per mile — comparable to a Prius in electric mode).
You just add the passenger compartment on top. Want a pickup truck or a hot rod? The choice is yours, provided you’ve got the chops to put it together.
Dave Had been working on a cell phone activated remote start for his car for a while when we posted the GSM car starter. While both do carry out the same job, we feel that there is enough good information here to share. He’s gone a pretty simple way, by connecting the vibrator motor leads to a headphone jack. He’s using that signal to then activate the remote start by setting off an extra fob. Though it is amazingly simple, this version does have an advantage. As he points out, his cell phone has several features which could be utilized to automate some of his car starts. He can set alarms as well as recurring calendar events to get his car started without his interaction. Lets just hope he doesn’t forget and let his car run too long unattended, especially if it is in a garage attached to his house.
A company calling its collective group of body monitoring products the WIN Human Recorder system has released a new device called the HRS-I. Designed to measure and record a person’s electrocardiographic signals, body surface temperature and overall body movements, the tiny unit can easily be worn under your shirt as you attend to your daily business.
The device communicates wirelessly with a remote base and can last on a single charge for up to three days. Targeted toward companies working to monitor employee health, the HRS-I can be purchased for just 30,000 yen ($331) and the monitoring service costs just 10,000 yen ($110) per month.
