Development of smartphone based controller for infrared helicopter

• Main Author: Thiang, Benjamin Li Peng.
• Other Authors: Vun Chan Hua, Nicholas
• Format: Final Year Project
• Language: English
• Published: 2013
• Subjects: DRNTU::Engineering::Computer science and engineering::Hardware::Integrated circuits; DRNTU::Engineering::Computer science and engineering::Software::Programming languages
• Online Access: http://hdl.handle.net/10356/51015
• Institution: Nanyang Technological University

Infrared (IR) controlled toys are becoming increasingly popular nowadays due to the fact of its relatively low manufacturing cost. As such, manufacturers are constantly coming up with new and innovative features to ensure that their products stay at the top of the market. One of the most noticeable one introduced recently is the option to allow one to use the smartphone to control the IR helicopter. This is typically done with the help of an external IR dongle connected to the phone’s earpiece port, together with an available application to provide the user interface. However, this option is rather restrictive since each manufacturer typically uses their own custom applications and dongles, which can only support their own brand of products. Therefore, if one were to control different brands of helicopters, they would need to purchase and use the different IR dongles for each respective toy. The main objective of this project is to develop a smartphone based remote control system for Infrared (IR) helicopters using the earpiece port as output for the main signal, together with options to implement other features that are deemed to be useful and unique. As the IR dongle is a relatively new product which makes use of the smartphone’s earpiece port, much of how the signals are transmitted remains unclear. In this project, investigations were performed to understand the format of the digital signals that the remote controller transmitted. Different sound files, corresponding to the various modulations used by the IR signals are created which can be played by using the smartphone’s media player. An android application was then developed to provide GUI means for the user to control the helicopter in the form of a touchscreen based remote controller. Based on the user’s inputs, the application will choose the corresponding sound files to combine into a full analog sound that is played through the smartphone’s earpiece port. The analog sound is then digitalized through a custom designed hardware circuit, which in turn emit the IR signals required to control the helicopter correspondingly.