Date of Award


Document Type

Thesis - SCU Access Only


Santa Clara : Santa Clara University, 2019


Computer Science and Engineering; Electrical and Computer Engineering; Mechanical Engineering

First Advisor

Christopher Kitts

Second Advisor

Sally Wood


The Robotic Systems Lab at Santa Clara University is working with the Monterey Bay Aquarium Research Institute to design and build a hybrid autonomous underwater / unmanned aerial vehicle (AUV/UAV). This system requires a variable buoyancy system (VBS) to control depth, pitch, and roll while the vehicle is submerged. A critical component of the VBS is the variable buoyancy devices (VBDs), composed of two 60 mL syringes and a linear actuator. Three VBDs take on water from the surrounding environment to change the weight and balance of the vehicle, thereby influencing its depth, pitch and roll. Given the use of depth and orientation sensors, a closed loop control system was developed to execute independent depth, pitch and roll commands. Functionality was verified and performance was characterized through tests in a pool, showing stable control with minimal steady state error. Additional testing was performed with a thruster, which proved the prototype’s ability to maintain depth during motion. The proof of concept system has been accepted by MBARI as a successful prototype for the current development effort.

SCU Access Only

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