Principles of the telemeter:
We have been working on this project for five months and we have acquired great knowledge about it. Let's start with an in-depth tour of the principles.
The parking sensor uses ultrasound to measure a distance. Humans cannot hear ultrasounds because they can only hear between 20 Hz and 20kHz while the ultrasounds are between 20 kHz and 10MHz. On the bumper, there are ultrasound emitters and receivers. Emitters send ultrasounds which are reflected by the obstacle. Receivers receive ultrasound. A software program calculates the distance between the car and the obstacle, based on the duration the ultrasound has to travel round trip, as well as its speed.
The reverse sensor is a relatively recent technology but the ultrasounds are an old discovery ( by Francis Galton in 1883).
Video of an exemple of a reverse sensor functionnement:
The Arduino card is essential to make a reverse sensor.
The Arduino card is an electronic card which does some information processing to measure the time that the ultrasounds take to go and come back. Knowing the speed of sound, it calculates the distance between the reverse sensor and an obstacle. Depending on the distance, the sensor beeps to warn the driver.
Our goal in this project is to create for ourselves a mobile reverse sensor.
We will also create the software program and add some gadgets. For example, when the temperature of air increases, the speed of sound travelling through the air increases. So we want to connect a temperature sensor to our Arduino card to have more precise speed of sound and therefore a more precise distance.
Here is a picture of our montage with the Arduino card and the emitter receiver.
Balmes Joëlle, Glory Antoine and Seguin Margaux