U.S. patent number RE36,643 [Application Number 09/067,697] was granted by the patent office on 2000-04-04 for buoyed sensor array communications system.
This patent grant is currently assigned to The United States of America as represented by the Secretary of the Navy. Invention is credited to Jack R. Olson, Barbara J. Sotirin, J. Mark Stevenson.
United States Patent |
RE36,643 |
Olson , et al. |
April 4, 2000 |
**Please see images for:
( Certificate of Correction ) ** |
Buoyed sensor array communications system
Abstract
A buoyed sensor array communications system comprises multiple
sensor syss electrically connected to a signal transmission line
which are positioned at predetermined locations along the signal
transmission line to form a linear sensor array. Each of the sensor
systems generates a data signal in response to receiving an address
signal. The system further includes; a processor system
electrically connected to the signal transmission line for
transmitting address signals to enable any one of the sensor
systems at a time in a selectively accessed order and has a data
storage memory for storing the data signal from each of the sensor
systems as stored data. A radio frequency transmitting system is
coupled to the data processor and transmits the stored data at a
predetermined time. A negatively buoyant structure connected to the
signal transmission line pulls the communications system to the
bottom of a body of water upon deployment. A positively buoyant
structure supports the processor system and radio frequency
transmitting system, and is connected to the signal transmission
line. A signal transmission line cutting system mounted in the
buoyant structure severs the signal transmission line upon receipt
of a cutting system enablement signal generated by said processor
system, whereupon the buoyant structure floats to the surface of
said body of water. Then the transmitting system transmits the
stored data.
Inventors: |
Olson; Jack R. (San Diego,
CA), Stevenson; J. Mark (San Diego, CA), Sotirin; Barbara
J. (Hanover, NH) |
Assignee: |
The United States of America as
represented by the Secretary of the Navy (Washington,
DC)
|
Family
ID: |
24615927 |
Appl.
No.: |
09/067,697 |
Filed: |
April 28, 1998 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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Reissue of: |
652206 |
May 23, 1996 |
05663927 |
Sep 2, 1997 |
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Current U.S.
Class: |
367/4;
340/870.16; 367/131; 367/153; 367/3; 367/76 |
Current CPC
Class: |
G01V
1/22 (20130101); G01V 1/38 (20130101); H04B
11/00 (20130101); H04B 13/02 (20130101); G01C
13/00 (20130101) |
Current International
Class: |
G01V
1/38 (20060101); G01V 1/22 (20060101); H04B
13/00 (20060101); H04B 13/02 (20060101); H04B
001/59 (); H04B 011/00 () |
Field of
Search: |
;367/3,4,76,78,79,129,131,153 ;441/2,33
;340/825.07,825.08,825.54,870.07,870.16 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Lobo; Ian J.
Attorney, Agent or Firm: FEndelman; Harvey Lipovsky; Peter
A. Kagan; Michael A.
Claims
We claim:
1. A buoyed sensor array communications system, comprising:
a signal transmission line;
multiple sensor systems electrically connected to said signal
transmission line, wherein one of said sensor systems at a time
generates a data signal in response to receiving an address
signal;
a processor system electrically connected in parallel to said
sensor systems for transmitting an address signal to enable any one
of said sensor systems in a selectively accessed order, and for
storing data encoded in each said data signal;
a radio frequency transmitting system for transmitting said stored
data;
a negatively buoyant structure connected to said signal
transmission line which sinks to the bottom of a body of water
after being deployed;
a positively buoyant structure for supporting said processor system
and said radio frequency transmitting system; and
a signal transmission line cutting system mounted in said
positively buoyant structure for severing said signal transmission
line upon receipt of a cutting system enablement signal generated
by said processor system, whereupon said positively buoyant
structure floats to the surface of said body of water.
2. The buoyed sensor array communications system of claim 1 wherein
each of said sensor systems includes:
an addressable switch having a unique address which generates a
first output signal in response to receiving one of said address
signals encoded with said unique address;
a power supply which provides a power signal upon receipt of said
first output signal from said addressable switch;
a sensor which generates said data signal in response to receiving
said power signal from said power supply;
a signal conditioning filter which filters said data signal;
and
an analog to digital converter for transforming said filtered data
signal into a digital data signal.
3. The buoyed sensor array communications system of claim 1 wherein
said signal transmission line is a two-wire system.
4. The buoyed sensor array communications system of claim 1 wherein
said negatively buoyant structure contains said signal transmission
line and said sensor systems prior to deployment of said sensor
array communications system.
5. The buoyed sensor array communications system of claim 1 wherein
said radio frequency transmitting system includes a modem.
6. The buoyed sensor array communications system of claim 1 wherein
said radio frequency transmitting system includes a cellular
telephone.
7. The buoyed sensor array communications system of claim 1 wherein
one of said sensor systems includes a pressure sensor.
8. The buoyed sensor array communications system of claim 1 wherein
one of said sensor systems includes a fluid velocity sensor.
9. The buoyed sensor array communications system of claim 1 wherein
one of said sensor systems includes a conductivity sensor.
10. The buoyed sensor array communications system of claim 1
wherein one of said sensor systems includes a temperature
sensor.
11. The buoyed sensor array communications system of claim 1
wherein one of said sensor systems includes a compass sensor.
12. The buoyed sensor array communications system of claim 1
wherein one of said sensor systems includes an accelerometer.
13. The buoyed sensor array communications system of claim 1
wherein one of said sensor systems includes an ocean current
sensor.
14. The buoyed sensor array communications system of claim 1
wherein one of said sensor systems includes a tilt sensor.
.Iadd.
15. A buoyed sensor array communications system, comprising:
a signal transmission line;
multiple sensor systems electrically connected to said signal
transmission line, wherein one of said sensor systems at a time
generates a data signal in response to receiving an address signal,
and each of said sensor systems includes:
an addressable switch having a unique address which generates a
first output signal in response to receiving an address signal
encoded with said unique address;
a battery energized power supply which provides a power signal upon
receipt of said first output signal from said addressable switch;
and
a sensor which generates said data signal in response to receiving
said power signal from said power supply;
a processor system electrically connected in parallel to said
sensor system for transmitting an address signal to enable any one
of said sensor systems in a selectively accessed order, and for
storing data encoded in said data signal; and
a radio frequency transmitting system for transmitting said stored
data. .Iaddend..Iadd.16. The sensor array communications system of
claim 15 wherein said signal transmission line is a two-wire
system. .Iaddend..Iadd.17. The sensor array communications system
of claim 15 further including a negatively buoyant structure
attached to said signal transmission line and which contains said
signal transmission line and said sensor systems prior to
deployment of said sensor array communications system.
.Iaddend..Iadd.18. The sensor array communications system of claim
15 wherein said radio frequency transmitting system includes a
modem. .Iaddend..Iadd.19. The sensor array communications system of
claim 15 wherein said radio frequency transmitting system includes
a cellular telephone. .Iaddend..Iadd.20. The sensor array
communications system of claim 15 wherein one of said sensor
systems includes a pressure sensor. .Iaddend..Iadd.21. The sensor
array communications system of claim 15 wherein one of said sensor
systems includes a fluid velocity sensor. .Iaddend..Iadd.22. The
sensor array communications system of claim 15 wherein one of said
sensor systems includes a conductivity sensor. .Iaddend..Iadd.23.
The sensor array communications system of claim 15 wherein one of
said sensor systems includes a temperature sensor.
.Iaddend..Iadd.24. The sensor array communications system of claim
15 wherein one of said sensor systems includes a compass sensor.
.Iaddend..Iadd.25. The sensor array communications system of claim
15 wherein one of said sensor systems includes an accelerometer.
.Iaddend..Iadd.26. The sensor array communications system of claim
15 wherein one of said sensor systems includes an ocean current
sensor. .Iaddend..Iadd.27. The sensor array communications system
of claim 15 wherein one of said sensor systems includes a tilt
sensor. .Iaddend..Iadd.28. The sensor array communications system
of claim 15 wherein one of said sensor systems includes a
positively buoyant structure for supporting said processor system
and said radio frequency transmitting system. .Iaddend..Iadd.29. A
buoyed sensor array communications system, comprising:
a signal transmission line;
multiple sensor systems electrically connected to said signal
transmission line, wherein one of said sensor systems at a time
generates a data signal in response to receiving an address
signal;
a processor system electrically connected in parallel to said
sensor systems for transmitting an address signal to enable any one
of said sensor systems in a selectively accessed order, and for
storing data encoded in each said data signal;
a radio frequency transmitting system for transmitting said stored
data;
a negatively buoyant structure connected to said signal
transmission line;
a positively buoyant structure for supporting said processor system
and said radio frequency transmitting system; and
a signal transmission line cutting system mounted in said
positively buoyant structure for severing said signal transmission
line upon receipt of a cutting system enablement signal generated
by said processor system.
.Iaddend..Iadd.30. The buoyed sensor array communications system of
claim 29 wherein each of said sensor systems includes:
an addressable switch having a unique address which generates a
first output signal in response to receiving one of said address
signals encoded with said unique address;
a power supply which provides a power signal upon receipt of said
first output signal from said addressable switch;
a sensor which generates said data signal response to receiving
said power signal from said power supply;
a signal conditioning filter which filters said data signal;
and
an analog to digital converter for transforming said filtered data
signal
into a digital data signal. .Iaddend..Iadd.31. The buoyed sensor
array communications system of claim 29 wherein said signal
transmission line is a two-wire system. .Iaddend..Iadd.32. The
buoyed sensor array communications system of claim 29 wherein said
negatively buoyant structure contains said signal transmission line
and said sensor systems prior to deployment of said sensor array
communications system. .Iaddend.
Description
BACKGROUND OF THE INVENTION
The invention relates to a sensor array communications system in
which time division multiplexing is used to enable any one of
multiple sensors in a selectively accessed access order.
Sensors for detecting physical characteristics of ocean
environments tend to be expensive and complicated, and are
typically incorporated into array systems which are heavy, bulky,
and power hungry. Deployment and recovery of sensor array systems
intended to be moored to the bottom of the ocean generally requires
large expenditures of manpower and ship time. A continuing need
exists for sensor array systems which are easy to deploy and
recover, as well as inexpensive to manufacture.
One type of sensor system intended to solve this continuing need is
taught in U.S. Pat. No. 5,272,476, "Data Acquisition System Having
Novel, Low Power Circuit For Time-division Multiplexing Sensor
Array Signals." The '476 patent describes multiple transceivers
linked to a control circuit by a two-wire signal transmission line.
The system employs time division multiplexing to enable each of the
transceivers in a non-varying sequence and at a sequence rate which
is cyclically repeated. This type of system performs well when it
is desirable to obtain data from each of the transceivers at the
sequence rate and cycle periodicity, as for example, in
applications where all of the sensors are of the same type. For
example, in an acoustic array, it may be desirable to repeatedly
sample the data from acoustic sensors, one at a time, and to
re-sample such sensors at periodic intervals. However, for sensor
arrays which include different types of sensors, such as compass
direction sensors, acoustic sensors, salinity sensors, and/or
current flow sensors, it may be preferable to sample the sensors at
different rates. For example, ocean conductivity typically changes
at a rate many orders of magnitude less than the rate at which the
acoustic properties of the environment may changes. For a sensor
array comprised of conductivity and acoustic sensors, it would be
wasteful of the generally limited electrical power capacity and the
limited data transmission rate of the data transmission line of the
system to repeatedly sample them at the same rate over and over.
Another disadvantage of the '476 system is that it requires that
the TDM transceivers be linked to the control circuit "C" with at
least four wires, or three wires with a sea water ground.
Therefore, a continuing need also exists for a sensor array system
comprised of multiple sensors in which each of the sensors may be
sampled any number of times, and in either a random or non-random
order, depending upon the requirements of a particular application.
A further need exists for a system in which the sensors are linked
to a central processor by less than three wires to reduce system
costs, bulk, and hydrodynamic drag.
SUMMARY OF THE INVENTION
A buoyed sensor array communications system comprises multiple
sensor systems electrically connected to a signal transmission line
which are positioned at predetermined locations along the signal
transmission line to form a distributed sensor array in space. A
"distributed" sensor array refers to a sensor array having sensors
which may be equally spaced or non-uniformly spaced. Each of the
sensor systems generates a data signal in response to receiving an
address signal.
The sensor array communications system comprises multiple sensor
systems electrically connected to a signal transmission line which
are positioned at predetermined locations along the signal
transmission line to form a linear sensor array. Each of the sensor
systems generates a data signal in response to receiving an address
signal. The system further includes; a processor system
electrically connected to the signal transmission line for
transmitting address signals to enable any one of the sensor
systems at a time in a random order and has a data storage memory
for storing the data signal from each of the sensor systems as
stored data. A radio frequency transmitting system is coupled to
the data processor and transmits the stored data at a predetermined
time. A negatively buoyant structure connected to the signal
transmission line pulls the communications system to the bottom of
a body of water upon deployment. A positively buoyant structure
supports the processor system and radio frequency transmitting
system, and is connected to the signal transmission line. A signal
transmission line cutting system mounted in the buoyant structure
severs the signal transmission line upon receipt of a cutting
system enablement signal generated by the processor system,
whereupon the buoyant structure floats to the surface of the water.
Then the transmitting system transmits the stored data as an RF
signal.
These and other advantages of the present invention will become
more readily apparent upon review of the following specification
taken in conjunction with accompanying figures and claims.
DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a buoyed sensor array communications system embodying
various features of the present invention which is suspended in a
vertical array.
FIG. 2 shows a typical sensor system connected to the data
processor via a two-wire signal transmission line.
FIG. 3 is an expanded block diagram of the sensor system of FIG.
1.
FIG. 4 shows the buoyed sensor array communications system of FIG.
1 after the buoyed structure has been released from the signal
transmission line.
FIG. 5 shows the signal line cutting system.
Throughout the several views, like elements are referenced using
like reference designations.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, there is illustrated an example of a buoyed
sensor array communications system 10 embodying various features of
the present invention which is shown to include a signal
transmission line 12, multiple sensors 16 electrically connected
and positioned along the signal transmission line 12 to form a
generally linear sensor array. When enabled, each of the sensors 16
generates a data signal in response to detecting a physical
characteristic of the environment. A very important advantage of
the communications system 10 is that the processor system 20
transmits address signals, one at a time, via signal line 12 to
enable any one of the sensor systems 16 at a time in a selectively
accessed order. The signal line 12 may be implemented as a two-wire
system comprising signal lines 13 and 15, as shown in FIG. 2, or as
a one-wire system that employs a sea-water ground. The enabled
sensor 16 then transforms environmental characteristics in the body
of water 36 into a data signal 68 (FIG. 3) that is provided to the
data processor 20 via the signal line 12 and stored in a memory
device, not shown. The other sensors 16 may also be enabled one at
a time in a selectively accessed order so that the entire array of
sensors 16 are not necessarily enabled in the same order or at some
fixed frequency. The phrase "selectively accessed order" means that
any one of the sensor systems 16 may be enabled in any particular
order, including a serial or non-serial order, and at a periodic or
non-periodic rate.
The processor 20 may be implemented as an Onset Computer Model 8
micro controller which includes a 256 kilobytes of flash memory and
a real time clock. The memory of processor 20 stores data encoded
in the data signals 68 (FIG. 3) as stored data. A radio frequency
transmitting system 24, which may be implemented for example, as an
RF modem or cellular telephone, transmits the stored data at a
selected time or upon satisfaction of some predetermined condition
via RF signal 90. An example of one such predetermined condition
results when the positively buoyant structure 40 floats on the
surface 44 of the water body 36. A negatively buoyant structure 28
is tethered to the signal transmission line 12 in accordance with
well known techniques so that after deployment, the negatively
buoyant structure 28 pulls the communications system 10 to the
bottom 32 of a body of water 36 such as the ocean or a lake. The
negatively buoyant structure 28 may be implemented as a metal
weight. However, materials other than metal may also be used, so
long as the structure 28 has negative buoyancy. When the negatively
buoyant structure 28 is implemented as a tube, the signal line and
attached sensor systems 16 may be coiled and stored in the tube.
However, while the communication system 10 is being deployed, the
positively buoyant structure 40 pulls on the signal transmission
line 12, causing the signal transmission line to pay out from the
tube-shaped negatively buoyant structure 28.
The processor 20 and radio frequency transmitter 24 are mounted in
a positively buoyant structure 40. In FIG. 1 the buoyant structure
is shown as having a generally frustrum shaped configuration.
However, the structure 40 may also be implemented using other
shapes. For example, the structure 40 may be tubular shaped and
made from ABS or polyethylene tubing, or from any other material
that is chemically resistant to sea water. The signal transmission
line 12 is connected, or tethered to the processor 20 so that the
buoyant force provided by the structure 40 pulls upwardly on the
signal transmission line 12, thereby assuring that the sensors 16
are positioned in an essentially vertical sensor array. At some
predetermined time, or upon satisfaction of some predetermined
condition, data processor 20 provides an output signal 81 to enable
signal transmission line cutting system 79 whereupon signal
transmission line 12 is severed. After signal transmission line 12
is severed, the structure 40 ascends to the surface 44 of the body
of water 36, as shown in FIG. 4. After rising to the surface 44,
the radio frequency transmitter 24 transmits the data stored in the
data processor 20 as RF signal 90 to a remote RF receiving station
via antenna 26, such as found on an orbiting satellite. A principal
advantage of the communications system 10 is that it provides
maximum flexibility in the acquisition of data by a vertical sensor
array. Another advantage of the present invention is that the
buoyant structure 40 will rise to the surface 44 of the body of
water 36, regardless of local currents.
The invention provides a structure that is much easier to design,
build, and implement compared to a system having a floating buoy
tethered directly to the bottom of the body of water. For example,
a buoy floating on the ocean surface and which is tethered to the
bottom of the sea is vulnerable to being pulled under water by a
combination of water currents and wave action. However, the present
invention is not affected by such conditions.
Referring to FIGS. 1 and 5 collectively, the signal line cutting
system 79 mounted in structure 40 includes an electrically actuated
linear solenoid 80 with an actuation rod 82, a cutting blade 84,
and a blade receptacle 88 which receives the blade in slot 85. The
blade 84 may be mounted to the rod 82 using threaded fasteners 86.
The blade receptacle 88 includes a semicircular recess 90 through
which a discrete length the signal transmission line 12 is
positioned. When data processor 20 generates cutting system
enablement signal 81, the actuation rod 82 is displaced, thereby
forcing the blade 84 to sever the signal transmission line 12 as
the blade 84 feeds into groove 85 of blade receptacle 88.
Referring to FIG. 3, sensor system 16 includes an address switch
60, sensor power system 64, sensor 67, signal conditioning system
70, and an analog-to-digital (A/D) converter 74. Each sensor system
16 is assigned a unique address. The address switch provides an
output signal 62 that enables sensor power system 64 only upon
receipt of a unique address signal for that particular sensor
system 16 via signal line 13 provided by the data processor 20 and
signal line 58. Signal line 58 electrically connects signal line 13
to the address switch 60. A suitable address switch may be
implemented as a Dallas Semiconductor Model D82407 Dual Addressable
Switch which includes a 1k-bit memory. Sensor power system 64 is a
conventional battery powered relay which when enabled, provides a
battery power signal 66 that energizes the sensor 67, signal
conditioning system 70, and A/D converter 74. Sensor 67 detects and
transduces an input signal 65, representing a physical
characteristic of the environment, into an analog electrical signal
68. Signal conditioning system 70 conventionally provides low-pass
and/or high-pass filtering of signal 68 to thereby generate a
filtered analog electrical signal 72. A/D converter 74 transforms
the analog signal into a digital signal 76 that is provided to the
data processor 20 via signal line 13. Address switch 60, sensor
power system 64, sensor 67, signal conditioning system 70, and A/D
converter 74 are grounded to data processor 20 by electrical
conductor 78 which is connected to signal line 15. Sensors 67 may
be implemented using any combination of sensors, as for example,
pressure, conductivity, temperature, acoustic, compass,
accelerometer, flow meter, tilt, and/or any other sensor suitable
for detecting an environmental characteristic of interest. The flow
meter sensor may be of the type described in commonly assigned U.S.
Pat. Nos. 4,308,753 and 4,000,648, each incorporated herein by
reference.
Signal lines 13 and 15 each may be implemented as Berk-Tek, Inc.
Model BTS-29-13P AWG29 wire. Such wire is polyethylene coated and
has a tensile strength of about 40 lbs. The polyethylene coating
provides good electrical insulation and is chemically resistant to
sea water. AWG29 wire has a very small diameter, thereby providing
the system with very low drag due to water currents flowing past
the system 10.
Obviously, many modifications and variations of the present
invention are possible in the light of the above teachings. It is
therefore to be understood that within the scope of the appended
claims, the invention may be practiced otherwise than as
specifically described. For example, while the implementation of
certain elements has been described with reference to components
identified using specific manufacturer model numbers, it is to be
understood that such elements may be otherwise implemented using
elements meeting the stated functional requirements. Further,
signal line 12 may be implemented as a one-wire system that employs
a sea-water ground.
* * * * *