Low cost phone charging system on a Bajaj boxer motorcycle

Abstract

Ideally, a mobile phone must be kept on during the day in order to conduct daily activities since it is the main means of communication in Uganda. However, given the heavy usage of mobile phones they come packaged with heavy applications. These drain the mobile phone battery very fast and they can last averagely for about 5 hours to 8 hours. The main objective of this project is to design a low cost mobile phone charging system for bajaj motorcycles which are commonly used for transport (bodaboda). We designed a circuit that transforms the motorcycle voltage (12V or 24V) to 5V which can charge mobile phones and other accessories, then also an automatic switch circuit that prevents the motorcycle battery from over discharge. A voltage regulator was used for the voltage transformation and a comparator was used to compare the input voltage whether it was above or below the expected operating voltage, that output was then used to either switch on or off the transistor. The circuit constructed was able to charge mobile devices though it was slow compared charging using electricity. It can be used to maintain battery power in devices which already have some charge.