Microglider Simulation Update!

       Hello! I’m Hugo, a student researcher in the LAIR. I work on the Microglider team, where we are trying to develop autonomous underwater glider robots. This robot will float and sink to reach operator-selected depths, controlled by electrolysis and vibration-assisted bubble leak. This will cause the robot to move laterally as lift forces act on the wings on the side of the glider. Among the work we have completed is a prototype of the robot that can float and sink under human control, a PD control system to set robot depth, and characterization of the robot’s electrolysis and leak rates. We want to model the robot using a simulation that includes the robot’s vertical and lateral position, as well as its pitch (tilting forward and backward). This simulation can then be translated into a control system that integrates robot dynamics, leak rate, and electrolysis rate to convert user inputs into desired robot position outputs. So far, I have already coded the robot dynamic physics into Matlab, and created a graphical output for the simulator.

Figure 1. Render of Primary Glider Elements and Design (Cutaway view)

        I am currently working on determining the theoretical parameters for the glider, including center of mass, center of pressure, buoyancy, and formulas for lift and drag coefficients at different angles. These are determined from a detailed CAD model of the glider (Figure 1), using finite element analysis in both Solidworks and COMSOL multiphysics. This will allow us to construct the simulation using more accurate parameters, to predict exactly how the robot will react to user inputs and control efforts, as well as changes to the glider design. The resulting simulation will be tuned to these parameters, yielding improvements to the current simulator (Figure 2).

Figure 2. GIF of Matlab Simulation Graphical Output, with a rectangle representing the robot body, black dots to represent the position at 0.01 second intervals, black arrow to represent glider pitch, and red arrow to indicate net velocity of the glider