Path Seeker Limited

Path Seeker
Path Tracking Control for Autonomous Road Vehicles > Project Overview

Path Seeker Overview

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Difficulties Encountered

Three main difficulties were encountered during the construction and testing of the path seeker:

Instability of the position sensor: due to causes that have not yet been determined, the photoreflectors in the position sensor exhibit random interference that alters its correct behaviour. The interference is strong enough to make the control algorithm fail (i.e. the microcontroller detects an incorrect or undefined input). Various theories have been formulated on the reason behind the interference, but we have no solid information that points towards a specific cause.

The microcontroller is too limited for the task at hand: the chosen microcontroller (Handyboard) is not powerful enough to yield a satisfactory sampling rate. This is one of the reasons why the Path Seeker had to be tested at a very low speed. Also, the team was going to use a PWM scheme to control the motor instead of an on-off switch. Unfortunately, all the processing power went into the controller and there was no resources left to be able to output a PWM signal of the desired frequency to control the motor. The budget of the project was very limited and we were not able to buy a more powerful microcontroller to replace the Handyboard.

Excessive battery weight: due to the need to isolate the power supply of the different components, three separate sets of batteries were installed on the Path Seeker. The three sets of batteries significantly increase the load on the motor and the Path Seeker's power supply tends to run out fairly fast (5 to 10 minutes). Some power consumption reduction strategy will be needed in the future.

This website has been designed for the ELEC / CENG 499 design project at the University of Victoria.
The Path Seeker project team's supervisor was Dr. Ashoka Bhat

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