As a technology provider we’ve always wanted to build products which would help people in their lives. That’s why we started to think about a device – a button which would help to stay secure for people whose work maybe dangerous. At Blast Lab we built a Panic button – a button which may save your health and life.
After we started creating security systems for our partners, we started thinking about creating a product for insurance and debt collection companies. Their employees are often in danger. The situation could be dangerous especially when a debtor is angry and employees of these companies have to get a return of the debt. This is the dark side of this job, which may be dangerous.
We wanted to ensure:
A panic button is a small device which weighs 20 grams. It is the size of a matchbox. It has one button, which allows for recording the audio, when you feel threatened. When you press the button the second time, the device sends an alert to the control panel at the headquarters. So if somebody threatens you or situation seems to be unclear, you would have a proof of the improper behavior.
The whole device is small because of the clear needs which we had to fulfill. It uses Bluetooth to connect to your phone, a small mic to record audio and has a battery which allows it to work for two days. However, the whole system which allows us to send recording to the server is not so simple. When we think about the conditions, in which recording audio may be priceless and can save somebody’s live, the owner may not be able to have a good Internet connection. There are some areas in which wireless network still doesn’t work efficiently. That’s why we decided to send data using a modified version of the normal call. The phone network is available nearly everywhere, so the chances to interrupt it are much smaller than with 3G or LTE connection.
We started to think about DTMF codes. These codes are sent when you type something on a numeric keyboard during a call. So we decided to generate the whole DTMF code in Android App. This wasn’t easy. In fact, it was one of the most research and work demanding tasks in the whole project. Fortunately we resolved it and finally, the app is working perfectly fine.
But when you want to send something using a phone network, it cannot be sent as easily as we may do it via the internet. To make it possible we needed to convert the sound few times.
Firstly we started to generate two different sounds. One of them was at 1209 Hz frequency, the other one was at 697 Hz. These two sounds correspond to the selection of 1 on the keyboard. These sounds were generated digitally, so it was easy to combine them into one sound using software. Then we put our sound in the Digital to analog converter, so the 8-bit file was converted to the real sound. Then we had to put this sound into microphone input in Panic button and send it to our phone. So the server would be able to make some actions based on the DTMF codes sent from your smartphone.
The prototype of the product is finished and ready to create first trial series out of it. Then we would be able to start the process of certification and bring the Panic button to the market. However, it is a product, which was built in 2013, so its story is probably finished. It has quite an interesting model of data transformation inside and uses traditional but amazingly reliable way of connection between the external device and your phone. Finally, we have created a product that suits the needs of our customers and that was our main goal.
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