Underwater Network Localization

Patrick Lazar, Tausif Shaikh, Johanna Thomas, Kaleel Mahmood

University of Connecticut Department of Electrical Engineering

Outline

• Objective• Range Test• Asynchronous Test• GUI• Test Bed• Future Tasks• Timeline• Budget

Objective

• Design a highly accurate localization system capable of being used on underwater vehicles.

• Implement localization algorithms for real time testing.

• Provide the AUV senior design group with an effective localization schematic that can be integrated into the AUV for underwater tracking.

Range Test

• Variance is approximately 0.08 m.• Add speed of sound

Range Test Results

0 5 10 15 20 250

5

10

15

20

25Node Data vs Theoretical Data

Theoretical DataLinear (Theoretical Data)Node Data

Actual Node Distance(m)

Test

Nod

e Di

stan

ce (m

)

0 5 10 15 20 250

5

10

15

20

25

f(x) = 1.00416970020539 x − 0.382800421553139

Average Node Data vs Theoretical

Node DataLinear (Node Data)

Actual Node Distance (m)

Test

Nod

e Di

stan

ce (m

)

Asynchronous Localization

Asynchronous Code Flow Chart

Start

Text Reader

Positioning Algorithm

Output to GUI

Node LocalizationSequence

Asynchronous Maximum Likelihood

• The asynchronous localization algorithm is centered around the above maximum likelihood equation which we implemented in C:

Swimming Pool7.96 7.83 6.54 8.99 9.72 3.45 9.54 7.83 7.8

7.96

7.96

7.96

7.96

7.96

8.99

8.99

8.99

8.99

8.99

6.54

6.54

6.54

6.5

6.54

9.72

9.72

9.72 9.72

9.727.83

7.83 3.45

3.45

3.45 3.45

3.45

7.8

7.8

7.8

4.12

4.12

4.12 4.12

4.12

4.1

6.77

6.77

6.77

6.77

6.77

5.33

6.54

2.85

2.85

2.85

2.85

3.27

3.27

3.2

8.32

8.32

8.329.44

3.76

3.76

3.76

9.9

8.4

6.6

5.5

8.91

0.05

AUV MLE

Graphical User Interface (GUI)

• A virtual representation of the asynchronous localization system.

• Read the coordinates of AUV from the output of the asynchronous algorithm.

• AUV will move to the correct position.• Software: QT Project

Graphical User Interface (GUI)

Test Bed

• Preform hardware testing and software verification before actual testing.– Check node sending/receiving capabilities – Calibrate node offsets.

• Allows us to quickly run simulations.

Test Bed

Budget

• Currently all our hardware needs are handled by the Underwater Sensor Network Lab.

• In terms of software the version of Code Composer studio we use is a free license version provided by the company.

• Spent:• $11.94 on battery for laser range finder• $22.83 on a bucket for the test bed• $965.23 left of $1000 Budget

Future WorkFuture Work

• Relative Mapping– Place all nodes into water.– Assume one node to be

the origin– Asynchronous clocks, no

other known positions.– Nodes send messages to

each other, use the range between nodes to create a map of their positions relative to one another.

• Lake Testing at Mansfield Hollow

TimelineSeptember

• Project Statement.

• Background research in existing Localization methods.

October

• Project specifications.

• Additional localization research.

• Coding C

November

• Code composer studio setup and completion of tutorial on coding in C.

• Finalize implementation plans.

December

• Ranging and noise pool tests using two nodes.

• Coding C algorithms.

January

• Ranging and pool tests using two nodes.

• Hardware setup of remaining nodes.

• Field testing of algorithms .

February

• Field testing of algorithms.

March

• Field testing of algorithms.

• Relative mapping research and implementation

April

• Integration of localization with other groups.

May

• Present completed project

Questions?