The main goal of the diploma thesis is to design and implement the control of a mobile platform. A vehicle, equipped with a microcontroller and two servomotors, must be guided by the microcomputer control algorithm on a flat surface to the final desired point, which is located a few centimeters in front of the camera. Feedback on the state of the system is provided by a digital camera connected to a personal computer, which communicates wirelessly with the microcontroller.
The thesis covers construction of a four-wheeled vehicle, connection of components, establishment of communication, recognition and determination of the position of the mobile device, and finally the heart of the problem - regulation. Control is realized using a PID controller. With it, we achieve the set goal - the vehicle must park in the desired position, lying a few centimeters in front of the camera, and it must be aligned with the axis of the visible area.
Wireless communication is much less robust than wired, and the closed-loop system must react correctly even in case of transmission delays. For this reason, after implementing a robust control algorithm that ensures the highest possible control quality in normal operation, we simulate operation with artificially added delays in the measurement system. In the presence of various delays, we adjust the controller parameters accordingly so that the system reaches the final position as soon as possible, while maintaining stability. The updated regulation is therefore more robust than the basic one at the expense of a slower response, since a possible delay in communication does not destabilize the system and despite the disturbance we reach the goal.
The result of the research is a robust control algorithm, which at the same time ensures high control quality, even if there is a greater delay of the measuring system. In the special case of electric motor drive regulation, we learn about one type of regulator.
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