This work is based on measuring the current and voltage of an electric bicycle and calculating its power and energy. One of our goals is to show results in different ways. The numerical value of the measurements will be showed on the smart phone. Both the TFT LCD screen connected to Arduino an the Processing program that can be used on a personal computer will be used for a graphical presentation.
There are a lot of different accessories and methods on the market for measuring current and voltage. But the cheapest and the most widespread device is definitely Arduino. It is available in different sizes, depending on our needs and complexity of our project. These devices offer different numbers of analog and digital inputs and outputs and even an internet connection.
The easiest way of current measuring is the use of ACS 712 sensor, working on principle of the Hall effectand available in three different sizes. The results have to be adapted to the size of the input current measurement with the voltage divider, made up of two resistors.
Our goal is also to send the data from Arduino to an android device using bluetooth. There are a lot of different ways, both professional and laic, to do this. In this project we used the easiest way to display data on the phone by using the MIT App Inventor and the S2 terminal, both of them totally free of charge and designed for beginners. The measurements are also going to be displayed on the LCD display.