Organize Meetings Management Power Systems › Low Power Consumption › Power Regulation Communications › Wireless Networking (Radio) › Global

Needs and Requirements AnalysisProject 7: DriftersLance Ellerbe - BS EE

Jamal Maduro - BS CpEPeter Rivera - BS ME

Anthony Sabido - BS ME

Drifter Design Team

Design Team – Project ManagerLance Ellerbe (Electrical Engineer)

Organize Meetings Management Power Systems

› Low Power Consumption› Power Regulation

Communications› Wireless Networking (Radio)› Global Positioning Systems (GPS)

Simulation (Hardware)› Hardware (physical components)› Overall system

Design Team – SecretaryJamal Maduro (Computer Engineer)

Record Meetings Catalogue and organize all documents Review and finalize deliverables Communications

› Wireless Networking (Radio)› Global Positioning Systems (GPS)

Microcontroller/FPGA Programmer Simulation (Software)

› Software (Microcontroller/FPGA)› Hardware (MATLAB Simulink)› Overall system (MATLAB Simulink)

Design Team – TreasurerPeter Rivera (Mechanical Engineer)

Ordering Parts Accounting Material Selection Hull Design

› 3-dimensional models› Engineering drawings

Structural Integrity Impact Resistance

Design Team – Business AdministratorAnthony Sabido (Mechanical Engineer)

Sponsor Relations Human Resources Material Selection Hull Design

› 3-dimensional models› Engineering drawings

Structural Integrity Impact Resistance

Needs Analysis

Legacy Drifter

*Picture courtesy of FSU Marine Lab

Project OverviewDevelop a self-contained network of tracked surface drifters for near coastal application.

›Housing›Electronics

Power SystemGPS receiverRadio transceiverMicrocontroller/FPGA

Any of these drifters within range of the base station will then be able to send all the information from all other drifters, thus providing a self-contained drifter network. Many such drifters are deployed globally by the National Oceanic and Atmospheric Administration (NOAA) as part of the world climate observation program.

Required Capabilities

CAP-01: › The drifters’ power sources have to exceed the

operational time of previous design (3 days) CAP-02:

› The drifters have to be able to transmit GPS data.

CAP-03: › The drifters must be able to communicate with

each other. CAP-04:

› The drifters must be water proof.

Desired Capabilities

CAP-05: › The network should be operational until the last

drifter is recovered. CAP-06:

› The drifters’ body design should increase water current drift and decrease wind drag.

CAP-07: › The drifters should be able to collect

Temperature data. CAP-08:

› The drifters should be camouflaged in water.

Operational Description

Client will take drifters out to the Ochlocknee Bay and release drifters into the water a set time intervals



The drifters will be tracked as they flow with the current to observe current patterns in the bay. The drifters communicate with each other as long as one drifter is in line of sight for communication.

Deployment Sites

recovery site or last valid GPS fix.

Drifter trajectories.

Dots represent the 5-minute interpolated positions:

an outgoing tide and

incomingtide.



Then the drifters will be recovered based on pin pointed locations using the GPS and wireless communication from one another.


Requirements Specifications

Functional Requirements REQF-01:

› The battery life time should be at least 15 days to increase operation time.

REQF-02:› There should be a minimum of 6000 GPS fixes, to

achieve a higher resolution of the GPS tracking data. REQF-03:

› The drifters must have a minimum range of 5 kilometers to facilitate the need for greater network coverage

REQF-04:› Each drifter must have a maximum weight of 0.5

kilograms, in order to achieve a lower waterline.

Functional Requirements REQF-05:

› Each drifter must have a maximum height of 10 cm (20 with antenna), in order to float through shallow waters.

REQF-06:› The drifters must be waterproof up to a depth of 5 meters,

to ensure that the electronic components remain safe from water damage at all times.

REQF-07:› The housing for the electronics must be able to withstand a

2.5 N force applied by a spherical surface with a 5mm radius, in order to insure the drifter’s survival of impacting oyster beds and boats.

REQF-08:› The device must be able to float over fresh waters less

than 0.25 m in depth, to ensure it does not run aground during extended periods of time out afloat.

Non-Functional Requirements

REQN-01:› The drifters must be entirely reproducible

without the need of out-sourcing any fabrication necessary.

REQN-02:› The radio frequency used in the transfer of

data between drifters should be an open frequency that does not require FCC licensing.

Constraints

CONS-01:› The cost of the materials and components may not

exceed $1000 for the fabrication of 5 drifters ($200 each).

CONS-02:› Each drifter should transfer data to nearby drifters via

radio wave transmission in no more than 1 minute. CONS-03:

› Engineering drawings for the housing must be created using SolidWorks or Pro-Engineer Wildfire.

CONS-04:› Circuit diagrams must be created using Pspice, Multisim,

or MATLAB.

Preliminary Test Plan

Capabilities & Requirements Testing

CAP-REQT-03: › After verifying that radio transceivers are functional, 1 drifter will be left

in a stationary location while all other radio transceivers are gradually moved away from the signal. Once radio transmissions fail, the distance between the testers and the drifter will be measured. (Dry and Wet test)

› Req. Tested: CAP-03, REQF-03, REQN-01, REQN-02› Materials Needed: Functional drifter, receiver› Location: College of Engineering› Testers: Any team member(s)› Steps:

1. Place base transceiver on a flat platform 6 inches out of a container filled with salt water that has the same salinity of average sea water in the gulf of Mexico (28 – 32 ppt).

2. Gradually displace radio transceivers from base station until loss of signal is observed

3. Use GPS to calculate distance 4. Repeat steps 1 – 3 in medium to heavily rainy conditions


CAP-REQT-06: › A fully assembled drifter hull, devoid of electronics but containing the

radio antenna, will be taken to a depth of 5 m and left alone for 24 hours. After the 24 hours pass, the drifter will be inspected for any leaks into the electronics compartment

› Req. Tested: CAP-04, REQF-06› Materials Needed: Assembled drifter hull, radio antenna, 5 m deep pool,

stop watch, a 5 kg weight, nylon rope.› Location: College of Engineering› Testers: Any team member(s)› Steps:

1. Attach the 15 kg weight to the drifter. 2. Attach the nylon rope to the drifter. 3. Using the nylon rope carefully let the drifter sink to the bottom of the

pool. 4. Tie the nylon rope to a secure post and let the drifter sit undisturbed for

24 hours. 5. Retrieve the drifter and inspect for leaks.

Constraints Testing

CONT-02:› Every step involved in the fabrication and use of a drifter

must be validated as feasible by the FSU Marine Lab. The FSU Marine lab must be able to accurately replicate every step in the fabrication process, in the event that more drifters are required.

› Req. Tested: CONS-03› Materials Needed:› Location: College of Engineering› Testers: Any team member(s)› Steps:

1. Present drifter test data to FSU Marine lab Review committee

2. Re-evaluate design is deemed necessary

ReferencesTechnical Report: “Surface Circulation Study of Waters Near Ochlockonee Bay, Florida”- Peter Lazarevich and Dr. Kevin Speer

Project Description : “Tracking the coastal waters: a wireless network of shallow water drifters”- FAMU-FSU College of Engineering

Appendix


CAP-REQT-01: › Run the complete network and measure the length of time that the

components last without failure and/or power loss (per drifter). Operation goal is 15 days (non-stop).

› Req. Tested: CAP-01, REQF-01› Materials Needed: Functional drifter, computer, stop watch, multi-

meter, oscilloscope.› Location: College of Engineering› Testers: Any team member(s)› Steps:

1. Individually attach all components to a multi-meter and oscilloscope and verify that components are operating within specifications

2. Assemble drifter circuitry and verify that all subsystems interact and operate within specifications3. Monitor multimeter and oscilloscope readings through LabView and review data for any indications that system fell below specifications during the 15 day test period.


CAP-REQT-02: › After verifying that GPS receivers are functional, run complete

program for 24 hours. At the end of the 24 hours, the number of GPS fixes will be measured; there should be at least 400 GPS fixes.

› Req. Tested: CAP-02, REQF-02› Materials Needed: Functional drifter, computer, stop watch.› Location: College of Engineering› Testers: Any team member(s)› Steps:

1. Place base transceiver on a flat platform 6 inches out of a container filled with salt water that has the same salinity of average sea water in the gulf of Mexico.

2. Record the amount of GPS fixes 3. Repeat steps 1 -2 in medium to heavily rainy conditions


REQT-04: › Complete drifter must be weighed to ensure that it

does not exceed the maximum weight requirement of 0.5 kg.

› Req. Tested: REQF-04› Materials Needed: Functional drifter, triple beam

balance› Location: College of Engineering› Testers: Any team member(s)› Steps:

1. Take a dry drifter and center it on the triple beam balance

2. Record Weight


REQT-05: › Each drifter must be fully assembled and measured from its lowest

point to the maximum upper point on the drifter, as well as to the very top of the antenna.

› Req. Tested: REQF-05› Materials Needed: Functional drifter, 2 rulers, string, table, right-

angle stands, 4 clamps, 1 level› Location: College of Engineering› Testers: Any team member(s)› Steps:

1. Attach the antenna to a string and hang from an elevated point. 2. Adjust the length of the string so that the lowest point of the drifter

contacts the surface of the table and is perpendicular to the table. 3. Verify that the drifter is being suspended vertically by using a level. 4. Measure various vertical dimensions by using the level to mark the

heights onto the right-angle stands. Use the ruler to measure the marks on the stands.


REQT-07: › A sample of the hull must be fabricated in identical fashion to the

actual hull. A force of 2.5 N will then be applied to the sample with a spherical end, 5 mm in radius. If the material withstands failure, increase force until failure occurs.

› Req. Tested: REQF-07› Materials Needed: Hull material sample, impact tester, spherical

impact end (5 mm radius)› Location: College of Engineering› Testers: Any team member(s)› Steps:

1. Secure the test sample into place. 2. Attach the spherical end. 3. Adjust the force on the impact tester to 2.5N 4. Impact the test sample 5. Inspect for signs of failure in the test sample such as: deformation,

fracture and indentations.


REQT-08:› The fully assembled drifter will be put in a tank of fresh

water with a depth of 0.25 m. The drifter must be able to float without obstruction under these conditions.

› Req. Tested: CONS-02, REQF-08› Materials Needed:› Location: College of Engineering› Testers: Any team member(s)› Steps:

1. Fill the tank to 0.25 m with fresh water (zero salt content).

2. Place drifter in the tank. 3. Inspect the drifter to ensure that it is indeed floating.

Constraints Testing

CONT-01:› Once the complete part list has been accumulated,

the summation of all the parts, materials, shipping and handling charges must be evaluated. If the grand total is above $1000, new parts and materials must be sourced in order to decrease the overall cost.

› Req. Tested: CONS-01› Materials Needed: Invoice(s)› Location: College of Engineering› Testers: Any team member(s)› Steps:

1. Review all invoices

Constraints Testing

CONT-03:› Engineering drawings must be saved as a PDF, so it may be

viewable by any one on any computer. If other programs aside from SolidWorks and Pro-Engineer are available, they may be used to create proper engineering drawings as long as they are saved as a PDF once completed.


1. Save documents to PDF file 2. Verify file opens and is readable on Linux, Mac, and

Windows Platforms

Constraints Testing

CONT-04:› Circuit diagrams must be saved as a PDF, so it may be

viewable by any one on any computer. If other programs aside from Pspice, Multisim, or MATLAB are available, they may be used to create proper engineering drawings as long as they are saved as a PDF once completed.


1. Save documents to PDF file 2. Verify file opens and is readable on Linux, Mac, and

Windows Platforms

Documents

Organize Meetings Management Power Systems › Low Power Consumption › Power Regulation Communications › Wireless Networking (Radio) › Global