marshall earle, ph.d., principal investigator mike brown, lead electrical engineer jeffrey...
TRANSCRIPT
Marshall Earle, Ph.D., Principal InvestigatorMike Brown, Lead Electrical EngineerJeffrey Gallagher, Electrical Engineer
(Bill Hughes, Lead Mechanical Engineer)
AN EASILY DEPLOYED AND RECOVEREDGPS-TRACKED WATER LEVEL BUOY
USM GPS Workshop - March 2004
NOAA SMALL BUSINESS INNOVATION RESEARCH(SBIR) PHASE II PROJECT
GPS-TRACKED BUOY
KEY SPECIFICATIONS
•Weight in air with battery packs 110 kgDiameter of hull 0.89 mHeight with radio antenna 1.37 mHeight w/o antenna 0.97 m•Nearly spherical hull with polycarbonate and anodized 6061T0 aluminum hemispheres, non-pinching gasket seal with stainless steel bolts, navigation lightOperating life 1 month•Operating Temperature Range -30oC to +60oC•Outputs: water level, significant wave height, average wave period, Data Quality Control (DQC) parameters
•See the preliminary specification sheet for additional information.
KEY COMPONENTS
•Topcon Legacy E GPS Topcon LegAnt GPS / GLONASS antennasMicrowave Data Systems narrow band CPFSK transceiver, operating at 410.0625 MHz (frequency band assigned to NOAA) Onset Computer Tattletale Model 8 microprocessorTexas Instruments MSP-430 microcontrollerMuRata ENV-05DB-52 angular rate sensors (3)Crossbow Technology CXL02TG3 tri-axial accelerometer•Carmanah Technologies 701 solar powered navigation light
BUOY IN SMALL PICKUP TRUCK BEFORE FIELD TEST
DOME REMOVAL / REPLACING
UPPER PLATE COMPONENTS
LOWER PLATE AND ELECTRONICS UNIT
ELECTRONICS UNIT INTERNAL VIEW
ELECTRONICS UNIT LABELLED COMPONENTS
BATTERY PACK REMOVAL / REPLACING
BUOY EXPLODED VIEW
BUOY CROSS SECTIONAL VIEW
PLANNED BUOY MODIFICATIONS
EXAMPLE BUOY MOORING
EXAMPLE SCREEN SHOT OF BUOY USER INTERFACE
Data steps are due to changing the buoy's water level in a test tank.
BUOY ELECTRONICS
SHORE STATION ELECTRONICS
WATER LEVEL CALCULATIONFLOWCHART
ELECTRONIC AND DATA ANALYSIS DESIGN
BASE STATION SETUP ON WAVELAND BEACH
CHECKING THE BUOY ON THE BEACH VIA ITS INFRA-RED PORT
REFERENCING TO BENCHMARKPANAMA CITY BEACH, FL, 1
Shore base station installed at benchmark.
REFERENCING TO BENCHMARKPANAMA CITY BEACH, FL, 2
Shore base station antenna installed in final position.
PANAMA CITY BEACH, FL, DATA COMPARISON
6 minute Tidal Measurements w/r to MLLW (ft)
0.00
0.50
1.00
1.50
2.00
2.50
3.00
3.50
18:0
0:00
0:48
:00
7:36
:00
14:2
4:00
21:1
2:00
4:00
:00
10:4
8:00
17:3
6:00
0:24
:00
7:12
:00
14:0
0:0
0
20:4
8:00
3:36
:00
10:2
4:00
17:1
2:00
0:00
:00
6:48
:00
13:3
6:00
20:2
4:00
3:1
2:00
10:0
0:00
16:4
8:00
23:3
6:00
6:24
:00
13:1
2:00
NSI Base Station
NOAA Tide Station
Error detection routine later added to remove infrequent spikes.
SMALL NOAA HYDROGRAPHIC VESSELUSED FOR CHESAPEAKE BAY, MD, DEPLOYMENT
BUOY DEPLOYMENTCHESAPEAKE BAY, MD
DEPLOYED BUOYCHESAPEAKE BAY, MD
CHESAPEAKE BAY, MD, DATA COMPARISON
Infra-red port lockup caused some data loss (corrected in operational design).
WATER LEVEL DATA COMPARISONS
•Panama City Beach, FL
RMS difference (including mean difference) 3.76 cmRMS difference (mean removed) 1.96 cm
•Chesapeake Bay, MD
Mean difference determined and removed at start of data collection.RMS difference 1.45 cm
WAVES (NOT MAIN RESEARCH GOAL)
•Wave height accuracy +/- 0.2 m (could reach +/- 0.1 m)•Wave period accuracy +/- 1.0 s (could reach +/- 0.5 s)
SignificantWave Height Average Wave Period
SUMMARY
A GPS-tracked water level buoy that can be easily deployed and recovered from small or large vessels has been successfully designed, built, and field tested.
The buoy is ready for transition to operational use to support hydrographic surveys and other applications.