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Autonomous BicycleBrekke, Snorre Eskeland January 2010 (has links)
The autonomous bike was conceived by Jens G. Balchen back in the eighties, and later picked up by Amund Skavhaug. The idea of a two-wheeled, self-powered, yet riderless bike has since been pursued intermittently over the years. Audun S{o}lvberg was the last person working on the project in 2007, making large headway towards the final goal of the bike: An outdoor ride, preformed by a riderless bicycle.The same goal is shared by this thesis; to make the bike work as intended and get the bicycle running outside. Additionally, as it would be naive to assume that this work would leave the bike in perfect condition, the thesis focuses on documenting issues that are left unfixed upon completion. Unfortunately, a fully functional, outdoor demonstration was not achieved, but half of the battle was won: Two of the three motors residing on the bike can be fully controlled by an external device.At the start of the work, the instrumentation system was mostly completed. A computer, running a QNX Neutrino Operating System, interfacing with potmeters, motors, Inertial Measurement Units and a GPS where available, mounted on the bike. Drivers communicating with the hardware was already written, and a Simulink model, meant to control the bike had been developed. However, the motherboard was in need of replacement, and the Simulink model was not finalized or even tested. The system was also lacking wireless networking capabilities.Yet, at the onset of the thesis, it was believed that the project was very close to reaching its ultimate goal.As the work progressed, several issues became apparent, emerging along with problems being solved. The motherboard was replaced with a motherboard{}, implicitly requiring a new hard drive to be installed. The OS was upgraded from version 6.3.0 to 6.4.1, to bring it up to date and as a requirement for some of the motherboard hardware. All of the device drivers where modified to work without their counterpart hardware connected, easing development of the Simulink model. The model was shown to be unreliable, but the hardware interface subsystem was completed and tested to allow for easy integration in separate projects. To demonstrate the capabilities of subsystem, a Bike Demo model was created, allowing the steer and pendulum to be controlled by the used of the bike accelerometer, using orientation data as reference. The intent was for the demo to serve as a control system for an outdoor ride. Ultimately the motor controller card was found to be incompatible with the propulsion motor, unable to deliver sufficient current. At the time of discovery, too little time reminded for the problem to be rectified. A demonstration of control system however, was successfully concluded.An attempt to bring wireless networking to the bike failed. Arguably too much time was spent making USB Wifi devices working with the QNX OS, when easier alternatives could perhaps have solved the problem earlier.The thesis has a large focus on the work ahead, as the system is complex and unreliable by its very nature. All known issues are detailed and summarized, and the various chapters describing hardware and software have been outlined in an attempt to serve as a go-to reference for students taking on the autonomous bike project in the future.
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