Project

# Title Team Members TA Documents Sponsor
48 Development of a better low-frequency microphone setup to measure complex acoustic impedance
Area Award: Acoustics
 Anna Czerepak
Kevin Looby
 Ryan Corey design_document0.pdf
final_paper0.pdf
presentation0.pdf
proposal0.pdf
Our project is concerned with developing a method and related hardware to measure acoustic impedances of various surfaces. The set up must meet the following specifications:
- Give accurate, consistent measurements of impedance at low frequencies: at least under 200 Hz, ideally under 100 Hz.
- Small profile, light weight
- Orientation that allows can be placed very close to the surface being measured to give more accurate values for acoustic impedance.
- Either a monopole or (true) dipole microphone setup. Which one we pick would have very drastic effects on what sort of processing is necessary on the software end and what information
- Capability to measure pressure gradient and/or particle velocity as a means of obtaining impedance.

Depending on what is found after more research and consulting, it may also be necessary to modify the source signal or possibly see if ambient noise alone would be feasible to extract acoustic information.

Possible tasks: use of an anechoic chamber (either in Everitt or in CERL) to calibrate and test the behavior of any prototype in the laboratory. Simulation of the microphone geometry and its effect on sound pressure level profiles (in COMSOL or a similar E&M finite element analysis program).

Autonomous Sailboat

Riley Baker, Arthur Liang, Lorenzo Rodriguez Perez

Autonomous Sailboat

Featured Project

# Autonomous Sailboat

Team Members:

- Riley Baker (rileymb3)

- Lorenzo Pérez (lr12)

- Arthur Liang (chianl2)

# Problem

WRSC (World Robotic Sailing Championship) is an autonomous sailing competition that aims at stimulating the development of autonomous marine robotics. In order to make autonomous sailing more accessible, some scholars have created a generic educational design. However, these models utilize expensive and scarce autopilot systems such as the Pixhawk Flight controller.

# Solution

The goal of this project is to make an affordable, user- friendly RC sailboat that can be used as a means of learning autonomous sailing on a smaller scale. The Autonomous Sailboat will have dual mode capability, allowing the operator to switch from manual to autonomous mode where the boat will maintain its current compass heading. The boat will transmit its sensor data back to base where the operator can use it to better the autonomous mode capability and keep track of the boat’s position in the water. Amateur sailors will benefit from the “return to base” functionality provided by the autonomous system.

# Solution Components

## On-board

### Sensors

Pixhawk - Connect GPS and compass sensors to microcontroller that allows for a stable state system within the autonomous mode. A shaft decoder that serves as a wind vane sensor that we plan to attach to the head of the mast to detect wind direction and speed. A compass/accelerometer sensor and GPS to detect the position of the boat and direction of travel.

### Actuators

2 servos - one winch servo that controls the orientation of the mainsail and one that controls that orientation of the rudder

### Communication devices

5 channel 2.4 GHz receiver - A receiver that will be used to select autonomous or manual mode and will trigger orders when in manual mode.

5 channel 2.4 GHz transmitter - A transmitter that will have the ability to switch between autonomous and manual mode. It will also transfer servos movements when in manual mode.

### Power

LiPo battery

## Ground control

Microcontroller - A microcontroller that records sensor output and servo settings for radio control and autonomous modes. Software on microcontroller processes the sensor input and determines the optimum rudder and sail winch servo settings needed to maintain a prescribed course for the given wind direction.

# Criterion For Success

1. Implement dual mode capability

2. Boat can maintain a given compass heading after being switched to autonomous mode and incorporates a “return to base” feature that returns the sailboat back to its starting position

3. Boat can record and transmit servo, sensor, and position data back to base

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