140 likes | 163 Views
P14251 Underwater Acoustic Communication. Greg Davis Scott Hambleton Jon Holton Chris Johnson Chris Monfredo. 5/13/14. Rochester Institute of Technology. 1. Underwater Acoustic Communication. Project Background
E N D
P14251 Underwater Acoustic Communication Greg Davis Scott Hambleton Jon HoltonChris Johnson • Chris Monfredo 5/13/14 Rochester Institute of Technology 1
Underwater Acoustic Communication Project Background • Boeing wants to improve it’s relationship with RIT through sponsoring projects that involve students in aquatic engineering challenges. This project is to design a limited bandwidth communication system. The system is to be able to send and receive information as well as have communication protocols that allow for multiple systems to be able to communicate in a swarm. • This system is acoustic based. Using a speaker and hydrophone, high frequency signals are to be sent between two watertight modules that are housing the electronics necessary to send and receive meaningful data. • 5/13/14 Rochester Institute of Technology 2
Underwater Acoustic Communication Project Goals To be able to send a signal 30 meters with high accuracy as quickly as possible. The system should be able to withstand pressures caused by 10 meters of water and should be able to resist corrosion and leaking. The system needs to be easily modified for the purposes of future expansion. The housing should be easily retrofitted to hold either future optical signal systems. • 5/13/14 Rochester Institute of Technology 3
Underwater Acoustic Communication Customer Needs • 5/13/14 Rochester Institute of Technology 4
Underwater Acoustic Communication Engineering Specifications 5/13/14 Rochester Institute of Technology 5
Underwater Acoustic Communication System Diagram • 5/13/14 Rochester Institute of Technology 6
Underwater Acoustic Communication Risk Analysis • 5/13/14 Rochester Institute of Technology 7
Underwater Acoustic Communication Full System Build 5/13/14 Rochester Institute of Technology 8
Underwater Acoustic Communication Full System Build 5/13/14 Rochester Institute of Technology 9
Underwater Acoustic Communication System Tests Mechanical • Watertight • Pressure resistance • Corrosion resistance Electrical • Signal Path Tracing • Power Systems • PCB Verification Computer • FFT Synchronization • Error Handling • Sending/Receiving Frames • 5/13/14 Rochester Institute of Technology 10
Underwater Acoustic Communication Results vs Specifications • 5/13/14 Rochester Institute of Technology 11
Underwater Acoustic Communication State of the Project The system is mostly functional. There are issues with the speaker and the fickle nature of this device has caused numerous problems. The software is functioning in one-way communication, but the code is in place to make it function in two-way. Messages can be sent reliably but at low speeds. The electronics are designed to support 4 FSK and should be easily integrated into future builds. The housing has a leak issue. After an overnight test there was a small amount of water inside the housing. • 5/13/14 Rochester Institute of Technology 12
Underwater Acoustic Communication Lessons Learned • BeagleBone Black vs. Raspberry Pi • Automatic Gain Control • Pulse Shaping • Power Amplifiers • PCB Design • Hydrophones • Power Converter Startup Current • 3-D Printing • Parabolic Dish Design • malloc() • Bit Collisions • 5/13/14 Rochester Institute of Technology 13
Underwater Acoustic Communication Recommendations For Improvements • Circuit Board Changes • New Acoustic Transmitter • Flyback Diodes • New FFT Package (FFTW) • Better Synchronization Algorithm • Fix ADC • 5/13/14 Rochester Institute of Technology 14