ONR Sea Otter

ONR Sea Otter
N00014‐09‐M‐0228
Rapid Mobile Geotechnical Measurement System for Amphibious Operations
Dr. Drake
ONR Coastal Geosciences Program
703‐696‐1206
C-2I, Inc
Arnis Mangolds
978-257-4820
amangolds@c-2iinc.com
C‐2I, Inc.
1
Problem & Approach • Establish and map trafficability in hostile near shore, estuarine, and riverine amphibious terrain
• Alternatives:
– Single point probes only good for uniform beaches, susceptible to drop error
– Drifters are unpredictable – Hyperspectral cannot penetrate murky or turbulent water
– SEAL teams are exposed and require considerable logistical support
• Bottom crawlers can cover large areas, obtain continuous data. C‐2I, Inc.
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Advantages of the Sea Otter
• Wide track capable of traversing weak soils
• Operates in high current environments (tested to 4kts)
• Independent of surface conditions
• Close and constant contact with sols for range sensitive instruments (e.g. magnetometers)
• Can operate tethered or non tethered
• Instrumentation can be mounted externally or internally
• Operates at 3 km/hr (though slower is better)
• Covers large area
• Easy deployment form surface craft, beach C‐2I, Inc.
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Sea Otter Output Data
• Penetration resistance • scaled CBR, CI, RCI relates to NATO trafficability model
• Continuous measurement to 18‐in depth
• Continuous measurement identifies channels, bars, other invisible features
•
•
•
•
•
Shear strength, draw bar pull or tractive effort
Ground slope (contour)
Surface ground roughness
Water depth Current speed and direction
• Simple to include visual reconnaissance, turbidity, comms surveys
C‐2I, Inc.
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110
1100
100
99
90
88
9
80
77
8
70
66
60
55
50
44
40
33
30
1
20
40
10
100
9
90
7
70
Meters
6
1
5
50
2
4
40
3
30
Meters
80
Elevation (Meters)
8
110
10
100
9
90
8
80
7
70
6
60
5
4
50
2
40
3
2
30
2
20
3
40
60
Meters
6
5
4
110’
3
2
1
100
00
10
80
100
0
Vehicle generated contour map
Actual contour map (USGS)
1
3
1
0
0
20
40
Meters
60
80
100
Meters
110
Legend
10
100
9
90
8
7
70
6
60
5
50
4
2
40
3
30
Elevation (Meters)
0
80
Meters
80
Elevation (Meters)
110
20
60
Contour map generated from
raw d ata
Raw altitude data
0
100’
Meters
Meters
10
7
1
10
20
11
10
22
20
60
Survey Area
El evatio n (Meters)
Meters
M eters
Contour maps generated by vehicle mounted barometer and tilt. Slope and obstacle alarms shown in red. 4
8
12 16
Degrees
20
24 28
1: 3” dia. Log
2: 8” dia. Log
3: 6” high Rock
2
20
3
1
10
0
20
40
60
80
100
0
Meters
C‐2I, Inc.
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Phase 1 Test Sites selected for worst case low bearing strength soil conditions
•Coastal plain Taunton clays with high plasticity •Sandy silts
•Silty sands
•Organic silts C‐2I, Inc.
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Vehicle mounted mast‐penetrometer correlated to NATO mobility model
Data has greater
sensitivity and
reliability than impact
based systems
Mounted in Sea Talon class
vehicle
F orc e vs . Dis plac ement
Herring R iver, C L , 1/8‐in rod, E ‐ penetrometer 16
14
12
10
F orc e (lbs )
8
6
Tes t 1, Upper S and,
Unmolded 4
2
0
0
1
2
3
4
5
6
7
8
9
10
‐2
Mounted on Lemmings
class vehicle
‐4
Displa c e m e nt (in)
C‐2I, Inc.
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Ripper provides continuous soil strength data. Alarms when penetrometer data should be taken
•Indicates soil changes
•Newer self cleaning system designed
•Strength changes confirmed with penetrometer data C‐2I, Inc.
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Testing performed on various vehicle chassis and correlated to standard soil mechanic instrumentation
•Tested in weak saturated marine sediments
•Compared to proving ring and hydraulic manual penetrometers
Lemmings vehicle in background,
Sea Talon in foreground
C‐2I, Inc.
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Test Vehicles Honeywell HPB200 Barometer
Garmin GPS
35HV
Rabbit 3000
Microcontroller
Microstrain 3DM
3-axis compass
C‐2I, Inc.
10
Autonomous Navigation: Herring River using Draper Labs algorithms
C‐2I, Inc.
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Tested radio based data exfiltration
Approach
ISM Transceiver
based on AD7021
ISM Transceiver
based on AD7023
COTS radio tested Test site; shore to far shore Non-US
Operation
(433 MHz
ISM)
5 ft [Note 1]: 1.4
NM
US Operation
(915 MHz
ISM)
5 ft: 0.8 NM
20 ft: 2.8 NM
20 ft: 1.5 NM
5 ft: 0.7 NM
5 ft: 0.4 NM
20 ft: 1.5 NM
20 ft: 0.8 NM
RKE Transmitter & 5 ft: 0.6 NM
Receiver, Receivers
based on Melexis
TH7111 (US
20 ft: 1.2 NM
Operation) & Linx
RXM-433-LR
(Non-US Operation)
5 ft: 0.3 NM
20 ft: 0.6 NM
Comments
- 100 bps operation (provides
very good sensitivity)
- More external parts
- Higher power consumption
- More mature part
- Has transmit capability from
tag (growth path)
- 1 kbps operation (pretty
good sensitivity)
- Fewer external parts
- Power consumption offset by
‘sleep’ & ‘wake-up’ features
- Very new part (preliminary
data sheets)
- Has transmit capability from
tag (growth path)
- Specifically designed for
world-wide ISM operation
- Very simple, low cost, low
power RKE transmitter and
receiver
- Very few external parts
- Will require two ‘flavors’ of
radio, or two radios built
together
Transmitter antenna at 1 ft and receiver at 5 ft offers 1.4 NM range 20 ft receiver antenna offers 2.8NM range
C‐2I, Inc.
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Wide track with interior alley for
smooth profile, low ground pressure
Wide track with external
instrumentation mounts
Mast and ripper extended
C‐2I, Inc.
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