[1] My Capstone Project — Decisions

As you become older, you realize that it is very difficult to know what you want. No matter if you are planning a big step or a small one. But wrinkles give you a shortcut: at least you know what you do not want.

With my -temporary- mentor, we were sure that giving the people the power to manage the status of a parking slot was not a brilliant idea. Besides, an Arduino can be converted into a watchful and cheaper way to alert when a slot is empty (or not).

Arduino has an extremely diverse list of sensors to work with: light, movement, temperature, sound, weight… We decided proximity was the sensor for our case. After some research, I found that the ultrasonic HC-SR04 is an incredibly cheap option for its preciseness.

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It was inspired by bats. As we know, bats have no eyes to fly so they developed an ultrasonic system to avoid obstacles.

This sensor operates by emitting an ultrasonic sound pulse and measuring the time it takes for the echo to return to calculate the distance to an object.

Very clever.

The measurement started immediately after I connected it to the Arduino and my first thought was ‘This thing is broken’ because the sensor was pointing to anything in the air and still it said that there was something at two meters of distance. I put my hand in front of it and the distance was reduced to five centimeters. I was amazed when I found out that the maximum distance it can measure is four meters, and my small department is no more than two meters long in any direction.

Since I started my career there was one thing that shocked me the most: the speed of the microprocessors. If you connect a led to an Arduino and you make it turn on and off, it will remain on because it does the job so fast that the human eye can not notice that the light blinks. Now the technology has hit me over: how this small piece of electronics can do such a job… At that moment I felt like a child again playing with cool stuff and I had that feeling when you confirmed that you made a good choice: this is what I want to work with.

More in this series:
[0] My Capstone Project — Basis