U.S. patent application number 12/074751 was filed with the patent office on 2009-01-01 for high performance security inspection system with physically isolated detection sensors.
This patent application is currently assigned to GE Security, Inc.. Invention is credited to Keith A. Clark, David E. Kresse, Brad Moyer.
Application Number | 20090000207 12/074751 |
Document ID | / |
Family ID | 38443369 |
Filed Date | 2009-01-01 |
United States Patent
Application |
20090000207 |
Kind Code |
A1 |
Clark; Keith A. ; et
al. |
January 1, 2009 |
High performance security inspection system with physically
isolated detection sensors
Abstract
A sealing mechanism for sealing an entrance aperture includes a
flange with an interface defining an entrance aperture. A first
drive shaft and a second drive shaft are coupled to a first drive
element. A first linear rail is positioned on a first side of the
entrance aperture. A first door linkage is pivotally coupled to a
door, and coupled to the first linear rail and to the first drive
element. A first pivoting cam is coupled to the first door linkage.
A first cam latch is positioned on the first side of the entrance
aperture and sized to receive the first pivoting cam. Contact
between the first cam latch and the first cam urges the door
inwardly at an angle relative to a direction of movement of the
door to urge the door to contact an outer edge of the interface
defining the entrance aperture.
Inventors: |
Clark; Keith A.; (La Mesa,
CA) ; Kresse; David E.; (Walnut Creek, CA) ;
Moyer; Brad; (San Diego, CA) |
Correspondence
Address: |
PATRICK W. RASCHE (22697);ARMSTRONG TEASDALE LLP
ONE METROPOLITAN SQUARE, SUITE 2600
ST. LOUIS
MO
63102-2740
US
|
Assignee: |
GE Security, Inc.
|
Family ID: |
38443369 |
Appl. No.: |
12/074751 |
Filed: |
March 6, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11363654 |
Feb 28, 2006 |
7358733 |
|
|
12074751 |
|
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Current U.S.
Class: |
49/506 ;
49/361 |
Current CPC
Class: |
G01V 5/0008
20130101 |
Class at
Publication: |
49/506 ;
49/361 |
International
Class: |
E05F 1/00 20060101
E05F001/00 |
Claims
1-33. (canceled)
34. A sealing mechanism for sealing an aperture, comprising: a
flange with an interface defining an entrance aperture; a first
drive shaft; a second drive shaft; a drive source for driving said
first drive shaft; left and right drive elements, each separately
connected to said first drive shaft and said second shaft; left and
right linear rails, each separately located on opposing sides of
said entrance aperture; left and right door linkages, each
pivotally attached to a door, said left and right door linkages
each being respectively received by said left and right linear
rails and respectively connected to said left and right drive
elements, wherein relative motion between said door and said
entrance aperture is obtained by driving said left and right drive
elements in one of two opposing directions; pivoting left and right
cams, each respectively attached to said left and right door
linkages; and left and right cam latches, each located on opposing
sides of said entrance aperture and sized to respectively receive
said left and right cams, wherein respective contact between said
left end right cam latches and said left and right cams cause said
door to travel inwardly at an angle relative to the direction of
travel of said door, causing said door to ultimately contact an
outer edge of said entrance aperture.
35. The sealing mechanism according to claim 34, further
comprising: a seal formed on said outer edge and facilitating
contact with said door.
36. The sealing mechanism according to claim 34, wherein said left
and right drive elements each comprise a belt.
37. A sealing mechanism for sealing an entrance aperture to isolate
an inspection system, said sealing mechanism comprising: a flange
with an interface defining the entrance aperture; a first drive
shaft; a second drive shaft; a first drive element coupled to said
first drive shaft and said second shaft; a first linear rail
positioned on a first side of the entrance aperture; a first door
linkage pivotally coupled to a door, said first door linkage
coupled to said first linear rail and coupled to said first drive
element, wherein relative motion of said door with respect to the
entrance aperture is obtained by driving said first drive element
in one of a first direction and an opposing second direction; a
first pivoting cam coupled to said first door linkage; and a first
cam latch positioned on said first side of the entrance aperture
and sized to receive said first pivoting cam, wherein contact
between said first cam latch and said first pivoting cam urges said
door to move inwardly at an angle relative to a direction of
movement of said door, urging said door to contact an outer edge of
said interface defining the entrance aperture.
38. The sealing mechanism according to claim 37, further
comprising: a seal formed on said outer edge and facilitating
contact with said door.
39. The sealing mechanism according to claim 37, wherein said first
drive element comprises a belt.
40. The sealing mechanism according to claim 37, further
comprising: a drive source for driving said first drive shaft;
41. The sealing mechanism according to claim 37, wherein said first
door linkage comprises: a carriage link; a first control arm
coupled to said carriage link at a first end of said carriage link;
a clamp coupled to said first drive element, and said first control
arm pivotally coupled to said clamp.
42. The sealing mechanism according to claim 41, wherein said first
control arm further comprises: a first pin coupling said carriage
link to said first control arm; and a second pin pivotally coupling
said door to said first control arm.
43. The sealing mechanism according to claim 41, wherein said first
door linkage further comprises: a first carriage slidably engaging
said first linear rail, and said carriage link coupled to said
first carriage.
44. The sealing mechanism according to claim 41, wherein said first
door linkage further comprises: a second control arm coupled to
said carriage link at an opposing second end of said carriage link;
and a turnbuckle pivotally coupled to said second control arm, and
operatively coupling said first control arm to said second control
arm.
45. The sealing mechanism according to claim 44, wherein said first
door linkage further comprises: a second carriage slidably engaging
said first linear rail, and said carriage link coupled to said
second carriage.
46. The sealing mechanism according to claim 41, wherein said first
door linkage further comprising: a bracket coupled to said carriage
link; and a spring coupled between said first control arm and said
bracket.
47. The sealing mechanism according to claim 41, wherein said first
door linkage further comprising: a cam spring coupled between said
first control arm and said carriage link.
48. The sealing mechanism according to claim 41, wherein said first
pivoting cam is pivotally positioned within a recess formed in said
carriage link, said first pivoting cam forming an open end
engageable with said first cam latch to urge an inner surface of
said door to contact a seal formed on said outer edge.
49. A method for sealing an entrance aperture defined by an
interface to isolate an inspection system, said method comprising:
coupling a door to a first drive element with a first door linkage,
the first door linkage coupled to a first linear rail positioned on
a first side of the entrance aperture; driving a first drive shaft
in a first rotational direction to move the first drive element
about the first drive shaft and a cooperating second drive shaft;
and engaging a first pivoting cam coupled to the first door linkage
with a cam latch positioned on the first side of the entrance
aperture to urge the door to move inwardly at an angle relative to
a direction of movement of the door, urging the door to contact an
outer edge of the interface defining the entrance aperture.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] Embodiments of the invention relate generally to a security
inspection system, and in particular to an inspection system that
provides physical isolation by mechanically, electromagneticly, and
radiologically isolating sensor technologies, from each other, and
the outside world to produce a system with a unique and novel
performance capability.
[0003] 2. Discussion of the Related Art
[0004] A number of different inspection and detection systems have
been developed for screening items such as passenger baggage,
checked baggage, packages, cargo, vehicles and the like. These
items may be screened for explosives, weapons, drugs, contraband,
threat objects, and other items of interest. Conventional
inspection systems operate using a variety of different
technologies including nuclear quadrupolar resonance (NQR), X-ray
computed tomography (CT), nuclear magnetic resonance (NMR), and
magnetic resonance imaging (MRI), among others. Regardless of which
technology the inspection system utilizes, the system typically
contains some type of sensor system. High performance is achieved
when each sensor is effectively isolated from other areas of the
system, and the outside world. This isolation is necessary to
optimize the inspection process to provide a high probability of
detection and a low probability of false alarm, and to protect the
outside environment from potentially harmful effects such as
electromagnetic interference and ionizing radiation.
[0005] For example, in a typical NQR inspection system, a conveyor
transports baggage into an inspection chamber defined by a radio
frequency (RF) coil. Once positioned within the RF coil, the
baggage is typically irradiated with pulses or sequences of pulses
of electromagnetic radiation. For proper operation, a conventional
NQR inspection system requires a structure, or active subsystem, in
order to provide the necessary electromagnetic interference/radio
frequency interference (EMI/RFI) shielding from external noise. A
tunnel, commonly known as a "wave guide below cut-off," is often
utilized to provide the necessary RFI shielding. In general, the
length of the tunnel is about the same as the maximum
cross-sectional dimension of the inspection chamber.
[0006] Inspection systems employing conveyers often utilize two
such tunnels. One tunnel is located at the entrance to the
inspection chamber, and a second tunnel is located at the exit. The
length of each tunnel of a typical passenger baggage inspection
system may range from about 24-48 inches, or more. The two
shielding tunnels can double the overall size of the inspection
system. In many applications, the size of the inspection system is
not particularly important. However, there has been recent interest
in utilizing increased numbers of inspection systems within
existing environments such as airports and seaports. In such
environments, space is limited and an inspection system having
reduced overall size is highly desirable.
SUMMARY OF THE INVENTION
[0007] Embodiments include an inspection system including a housing
having a cavity which defines an inspection zone, and a positioning
device within the inspection zone which provides positioning of a
specimen within the inspection zone. The inspection system may also
include a sensor system for inspecting the specimen, and an
entrance aperture formed in the housing. The entrance aperture may
be sized to permit the specimen to pass through the entrance
aperture. The inspection system also includes a sealing mechanism,
such as a door, which cooperates with the positioning device. The
sealing mechanism is operatively coupled to the housing and
selectively positionable between open and closed positions. The
open position permits the specimen to pass through the entrance
aperture, and the closed position seals the entrance aperture to
effectively isolate the inspection system.
[0008] Additional embodiments include a method for inspecting
specimens. The method includes selectively operating a positioning
device located within a housing having a cavity which defines an
inspection zone; selectively operating a first sealing mechanism
operatively coupled to the housing, the first sealing mechanism
being selectively positionable between open and closed positions,
the open position permitting a specimen to pass through an entrance
aperture and to come into contact with the positioning device, and
the closed position sealing the entrance aperture to effectively
isolate the inspection system; and inspecting the specimen for an
item of interest after the first sealing mechanism is positioned in
the closed position.
[0009] Additional embodiments include a sealing mechanism for
sealing an aperture. The sealing mechanism includes a flange with
an interface defining an entrance aperture; a first drive shaft; a
second drive shaft; and a drive source for driving the first drive
shaft. Left and right drive elements are each separately connected
to the first drive shaft and the second shaft. Left and right
linear rails are each separately located on opposing sides of the
entrance aperture. Left and right door linkages are each pivotally
attached to a door, the left and right door linkages each being
respectively received by the left and right linear rails and
respectively connected to the left and right drive elements.
Relative motion between the door and the entrance aperture is
obtained by driving the left and right drive elements in one of two
opposing directions. Pivoting left and right cams are each
respectively attached to the left and right door linkages. Left and
right cam latches are each located on opposing sides of the
entrance aperture and sized to respectively receive the left and
right cams. Respective contact between the left and right cam
latches and the left and right cams cause the door to travel
inwardly at an angle relative to the direction of travel of the
door, causing the door to ultimately contact an outer edge of the
entrance aperture.
BRIEF DESCRIPTION OF THE DRAWING
[0010] The above and other aspects, features, and advantages of
embodiments of the invention will become more apparent upon
consideration of the following description of preferred
embodiments, taken in conjunction with the accompanying drawing
figures, wherein:
[0011] FIGS. 1 through 3 are perspective views of an inspection
system in accordance with embodiments of the invention;
[0012] FIGS. 4 through 7 are side views of the inspection system of
FIGS. 1-3, and collectively show a generalized example of a baggage
inspection process;
[0013] FIG. 8 is a side view of an inspection system having doors
positioned on the inside of the housing;
[0014] FIG. 9 is a side view of an inspection system having doors
composed of two door panels;
[0015] FIG. 10 through 12 collectively show a generalized example
of a baggage inspection process using a single door inspection
system;
[0016] FIG. 13 through 16 collectively show a generalized example
of a baggage inspection process using a two door inspection
system;
[0017] FIG. 17 is a flowchart showing exemplary operations for
inspecting a specimen for an item of interest;
[0018] FIG. 18 is block diagram of a system, in accordance with an
embodiment of the invention, which may be implemented to control,
manage, operate, and monitor, the inspection system of FIGS.
1-3;
[0019] FIGS. 19 through 21 are perspective views of an alternative
sealing mechanism attached to an inspection system;
[0020] FIG. 22 is a front view of the inspection system shown in
FIGS. 19 through 21, but the sliding door and associated linkage
have been omitted to reveal the underlying structures;
[0021] FIG. 23 is a close-up partial view of the upper left side of
the sealing mechanism of FIGS. 19 through 21, portions of the door
linkage having been omitted for clarity;
[0022] FIG. 24 is a perspective view of door linkage components
that may be implemented in the sealing mechanism of FIGS. 19
through 21;
[0023] FIG. 25 is a close-up partial view of the upper left side of
the sealing mechanism of FIGS. 19 through 21;
[0024] FIG. 26 is a close-up view of the top portion of the
left-side door linkage, from the viewpoint of looking away from the
housing of the inspection system;
[0025] FIG. 27 is a close-up view of the same top portion of the
door linkage which is shown in FIG. 26, but from the viewpoint of
looking toward the housing of the inspection system;
[0026] FIG. 28 is a close-up view of the upper left side of the
sealing mechanism, portions of the door linkage having been omitted
for clarity;
[0027] FIG. 29 is the same view of the sealing mechanism shown in
FIG. 28, but the door has been moved downward partially exposing
the entrance aperture;
[0028] FIG. 30 is a close-up view of a cam which may be used in the
upper control arm of FIG. 31;
[0029] FIG. 31 is a close-up view of an upper control arm which may
be used as part of the door linkage shown in, for example, FIGS. 24
through 27; and
[0030] FIG. 32 is a close-up view of a door which may be
implemented by the closing mechanism shown in, for example, FIGS.
19 through 21.
DETAILED DESCRIPTION OF EMBODIMENTS
[0031] In the following detailed description, reference is made to
the accompanying drawing figures which form a part hereof, and
which show by way of illustration specific embodiments of the
invention. It is to be understood by those of ordinary skill in
this technological field that other embodiments may be utilized,
and structural, electrical, as well as procedural changes may be
made without departing from the scope of embodiments of the
invention.
[0032] FIG. 1 is a perspective view of inspection system 10.
Housing 15 contains a defined inspection zone 20 for which sensor
system 25 can inspect baggage 30 for items of interest. The baggage
may be introduced to the inspection zone via entrance aperture 35.
The inspection system typically contains a device for positioning a
specimen, such as baggage 30, within the inspection zone. In the
embodiment of FIG. 1, conveyor 40 receives and positions the
baggage within the inspection zone. An external conveyor (not shown
in this figure), for example, may be used for introducing the
baggage to the interior conveyor 40.
[0033] Entrance door 45 is shown operatively coupled to housing 15,
and is selectively positionable, horizontally or vertically,
relative to entrance aperture 35. In some embodiments, the entrance
door is closed by vertically moving the door relative to the
entrance aperture. In FIG. 1, the entrance door is in the open
position. In FIG. 2, the entrance door has been moved vertically
upward, and is in the partially closed position. FIG. 3 shows the
entrance door in the fully closed position. Opening of the entrance
door would essentially be the reverse of this process such that the
door would be moved vertically downward from the position shown in
FIG. 3 to the door position shown in FIG. 1. Inspection system 10
is also configured with an exit aperture and associated exit door.
These components are not readily viewable in FIGS. 1 through 3, but
they are shown in more detail in later figures. The exit door
functions in a manner similar to entrance door 45.
[0034] Inspection system 10 includes sensor system 25, as
identified above. As used herein, the term "sensor system" is used
to refer to any type of spectroscopy or imaging system which is
capable of inspecting a specimen, such as baggage 30. Particular
examples of suitable sensor systems include those which implement
one or more technologies such as nuclear quadrupolar resonance
(NQR), nuclear magnetic resonance (NMR), magnetic resonance imaging
(MRI), X-ray computed tomography (CT), projection X-ray,
single-view X-ray sensor, multi-view X-ray sensor, smart X-ray,
chemical trace detection, millimeter-wave (mm-wave) imaging,
terahertz (THz) imaging, laminagraphy, and nuclear detection for
detecting threshold levels of radioactive materials, among others.
Specific items of interest for which a specimen may be inspected or
otherwise interrogated by the sensor system include explosives,
contraband, and illegal or controlled substances such as cocaine,
heroin, and MDMA. An appropriately configured sensor system can
detect a wide range of explosives such as those containing PETN,
RDX, TNT, Tetryl, Ammonium Nitrate (AN), black powder, and the
like. Non-destructive testing and analysis applications are also
possible.
[0035] Inspection system 10 is shown with entrance and exit
apertures, and corresponding entrance and exit doors, which are
rectangular. However, other configurations (for example, circular,
oval, triangular, etc.) are possible, and may be implemented using
the teachings of the present disclosure.
[0036] FIGS. 4 through 7 are side views of inspection system 10,
and collectively show a generalized example of a baggage inspection
process. Separate baggage items which may be inspected by the
system are represented by reference numerals 30a, 30b, and 30c. For
simplicity, sensor system 25 is shown schematically as block 25.
However, in practical applications, the sensor system may include a
number of system components, each positioned at various locations
within the inspection system.
[0037] FIG. 4 shows entrance door 45 and exit door 55 in the open
position, exposing entrance aperture 35 and exit aperture 60,
respectively. Conversely, FIG. 5 shows the entrance and exit doors
after these structures have been moved into the closed position,
effectively isolating the baggage within the inspection system.
[0038] One function of entrance and exit doors 45 and 55 is to
provide a sealing mechanism which effectively isolates, during an
inspection process, the sensor system and inspected baggage. The
entrance and exit doors provide sensor system 25 with shielding
from external interference. At the same time, these doors protect
the outside environment by inhibiting the release of unwanted or
undesirable artifacts (for example, electromagnetic interference
(EMI)) generated by the sensor system operating within the
inspection system. In general, the sealing mechanism of the
inspection system provides, for example, one or more of:
electromagnetic shielding, ionizing radiation isolation,
atmospheric isolation, optical isolation, thermal isolation and
control, and mechanical isolation, among others.
[0039] The type of material and specific structure of the entrance
and exit doors is typically selected based upon the type of sensor
system utilized, and the type of isolation desired (internal,
external, or both). Each type of sensor system (for example, QR,
CT, chemical trace) will typically have its own unique isolation
requirement. As such, the structural requirements of housing 15 and
the entrance and exit doors will vary depending upon the type of
sensor system utilized within the inspection system.
[0040] For example, in one embodiment, sensor system 25 may be
implemented using a conventional QR sheet coil or tube array coil
system configured to detect the presence of explosives in baggage
using nuclear quadrupole resonance (NQR). In such an embodiment,
optimal isolation may be achieved by electrically connecting and
grounding the housing which encloses the QR sensor system. This may
be accomplished by forming entrance and exit doors from a material
which electrically conductively isolates the housing and included
components when these doors are closed. When closed, these doors
provide a range of attenuation of anywhere from 70 dB to 120 dB, or
higher. The entrance and exit doors may be hollow or solid
structures. Alternatively, the doors may be partially hollow and
contain support baffling or structures (for example, a honeycomb
structure) to increase the structural integrity of the door.
Typically, the surface of the door which contacts electrically
conductive portions of the housing is formed from a conductive
material such copper, aluminum, and the like.
[0041] In other embodiments, sensor system 25 is implemented using
various types of projection X-ray systems. These embodiments will
not require conductive isolation as does the just-described QR
sensor. Instead, optimal isolation for the X-ray system may be
achieved by effectively containing the X-rays emitted by the x-ray
system. In such embodiments, entrance and exit doors 45 and 55 may
be formed from any material which provides the necessary
containment of the radiation generated by the X-ray system. Metals
may be used for electromagnetic shielding (e.g., NQR, NMR, MRI,
microwave, mmwave, THz) and include, but are not limited to,
copper, gold, silver, nickel, etc. High-z materials may be used for
radiological shielding (X-ray computed tomography (CT), projection
X-ray, single-view X-ray sensor, multi-view X-ray sensor, smart
X-ray sensors). Metals/composites may be used to manipulate
electromagnetic fields, including tailored meta-materials (e.g.,
isolation and control for microwave, mmwave, THz sensors).
[0042] Various types of materials and structures which may be used
for the entrance and exit doors have been described. However, it is
to be understood that these components do not require any specific
material or structure, and that any of a variety of different
materials and door configurations which provide a desired isolation
(electromagnetic, radiation, atmospheric, and so on) may be
implemented.
[0043] Inspection system 10 provides the necessary isolation using
entrance and exit doors 45 and 55, and does not therefore require
open tunnel structures (although such tunnels may be configured
with entrance and exits doors if so desired). Since tunnels are not
required, the overall size of the inspection system may be reduced,
which is desirable in size-limited applications such as airport and
seaport baggage handling locations. In addition, multiple
inspection systems, each having the same or different sensor
system, may be placed in relatively close proximity. Such
arrangements are possible without sacrificing performance since
each inspection system is effectively isolated.
[0044] As a matter of convenience, embodiments will be described in
the context of a baggage inspection system utilizing a sensor
system having a NQR sensor. Particular reference will be made to
"baggage" which is inspected for explosives, contraband, threat
objects, and other items of interest using the NQR sensor. However,
it is to be understood that embodiments of the invention are not so
limited and that the teachings herein apply equally to other sensor
systems and to the inspection of other types of specimens. The
terms "baggage" and "specimen" are used herein to generally define
items that may be inspected by an inspection system. In some
instances, these items may contain, or be constructed of, various
types of explosive materials. Possible types of baggage and
specimens include, for example, passenger baggage, checked baggage,
parcels, mail, packages, containers, cargo, vehicles, people,
laptop or portable computers, and the like. In non-destructive
testing applications, specimens may include materials, products,
system components, and organic materials, among others.
[0045] Referring back to FIG. 4, conveyor 50 is shown advancing
baggage 30a toward entrance aperture 35. Entrance door 45 and exit
door 55 are in the open position, exposing entrance aperture 35 and
exit aperture 60. In FIG. 5, conveyor 40 positions baggage 30a
within inspection zone 20, and the entrance and exit doors are
moved vertically upward into the closed position. Since the
entrance and exit doors are closed, the baggage and sensor system
are effectively isolated within the inspection system. Note that
conveyor 50 has queued baggage 30b. At this point, sensor system 25
inspects baggage 30a according to the particular technology
utilized by the sensor system (for example, NQR, CT, NMR, and the
like).
[0046] In accordance with one embodiment, sensor system 25 is
implemented using a conventional QR sheet coil or tube array coil
system configured to detect the presence of explosives in baggage
using nuclear quadrupole resonance (NQR). An appropriately
configured QR sensor system can detect a wide range of explosives
and illegal drugs.
[0047] NQR is a branch of radio frequency spectroscopy that has
been used for the detection of explosives and drugs. NQR exploits
the inherent electrical properties of atomic nuclei. Nuclei with
non-spherical electric charge distributions possess electric
quadrupole moments. In solid materials, electrons and atomic nuclei
produce electric field gradients. These electric field gradients
interact with the nuclear quadrupole moments of quadrupolar nuclei,
producing energy levels for the quadrupolar nuclei, and hence their
characteristic transition frequencies. Measurements of these
frequencies, or relaxation time constants, or both, can indicate
not only which nuclei are present but also their chemical
environment.
[0048] In the inspection process, using carefully tuned pulses of
low intensity electromagnetic (RF) waves, a quadrupole resonance
device probes the molecular structure of targeted items such as
explosives and narcotics. The effects of quadruple resonance
momentarily disturb the alignment of target nuclei within the item
scanned. As the nuclei realign themselves after the RF energy is
turned off, they emit a characteristic signal of their own, which
is picked up by a receiver and sent to a computer for rapid
analysis. The signal emitted by each type of explosive or illegal
drug is unique. Specialized RF pulse sequences have been developed
for optimal detection of particular explosives and illegal drugs
such as cocaine and heroin. RF signal production and the detection
of NQR return signals may be accomplished using, for example, the
techniques disclosed in U.S. Pat. No. 5,592,083, or U.S.
application Ser. No. 10/651,657, entitled "TUBE ARRAY COIL FOR
QUADRUPOLE RESONANCE (QR) SCANNING, filed on Aug. 29, 2003, both of
which are assigned to Quantum Magnetics, Inc., of San Diego,
Calif.
[0049] In general, a suitable QR sensor includes a RF subsystem in
communication with a QR sheet coil or a QR tube array coil. Using
well-known techniques, the RF subsystem may utilize a variable
frequency RF source to provide RF excitation signals at a frequency
generally corresponding to a predetermined, characteristic NQR
frequency of a specimen. During the inspection process, the RF
excitation signals generated by the RF source may be introduced
into the specimen. In some embodiments, the QR sheet coil or QR
tube array coil may serve as a pickup coil for NQR signals
generated by the specimen, thus providing an NQR output signal
which may be sampled to determine the presence of target substance,
such as an explosive.
[0050] As shown in FIG. 6, after the just-described inspection
process has been completed, entrance and exit doors 45 and 55 may
each be moved vertically downward to expose entrance and exit
apertures 35 and 60, respectively. Conveyor 40 then advances
baggage 30a through inspection zone 20 where it is received by exit
conveyor 65. At about the same time, or substantially the same
time, entrance conveyor 50 advances baggage 30b toward the
inspection system where it is received and positioned by conveyor
40. In FIG. 7, conveyor 65 carries baggage 30a away from the
inspection system. In addition, conveyor 40 has positioned baggage
30b within the inspection zone, and conveyor 50 has queued baggage
30c. Baggage 30b may then be inspected by sensor system 25, and the
just-described process may be repeated continuously for different
baggage items.
[0051] Specific reference is made to the use of conveyors to carry
baggage to and from the inspection system, as well as for
positioning the baggage within the inspection zone. However,
embodiments of the invention are not so limited and almost any type
of positioning or transport device or system, which can support the
baggage transportation requirements of the inspection system, may
alternatively be used.
[0052] Synchronizing the various components of the inspection
system (for example, conveyors 40, 50, and 65, and entrance and
exit doors 45 and 55) may reduce the amount of time required to
position, scan, and remove the baggage from the inspection zone.
Time savings may be on the order of a few seconds per baggage item,
which would amount to a significant reduction in overall inspection
time in environments, such as airports, which experience workloads
of several hundred bags-per-hour.
[0053] Entrance and exit doors 45 and 55 may be controlled using
any number of positioning mechanisms which are capable of providing
relative motion between the doors and their associated apertures.
For instance, the doors may be slideably coupled to linear rails
positioned near the entrance and exit apertures. The doors may then
be driven using a suitable drive mechanism such as a pneumatic
drive, a hydraulic drive, a magnetic drive, a rail gun, belts,
chains, ropes, or any other device which provides the necessary
positioning of the doors. Specific examples of various types of
door positioning mechanisms will be described in more detail in
conjunction with later figures.
[0054] A number of different embodiments have been described in
which two separate doors, move vertically relative to the travel
path of inspected baggage. However, many alternative embodiments
are possible. For instance, the inspection system may be
implemented with only a single door. Referring to FIG. 4 as an
example, such an embodiment would have entrance door 45, but exit
door 55 and exit aperture 60 would be omitted. Inspection of
baggage would proceed in a manner similar to that previously
described, with the primary distinction being that the baggage
enters and exits the inspection system through the same aperture
(for example, entrance aperture 35).
[0055] Another alternative is to arrange the entrance and exit
doors so that they close downward in a vertical path relative to
the travel path of inspected baggage. This may be accomplished by
locating entrance and exit doors 45 and 55 above, not below,
entrance and exit apertures 35 and 60. Similarly, the entrance and
exit doors may also be arranged so that they each open and close in
a horizontal path relative to the travel path of inspected baggage.
This may be accomplished by locating entrance and exit doors 45 and
55 on either side of the entrance and exit apertures. Other
possibilities include implementing one or more doors that rotate
relative to an associated entrance or exit aperture, or the use of
hinged doors. It should be understood that the entrance door may
operate in one manner or direction, which differs from the manner
or direction of the exit door.
[0056] Still further embodiments are shown in FIGS. 8 and 9. In
FIG. 8, entrance and exit doors 45 and 55 are shown operating
internally within housing 15. In this figure, the entrance door is
in the open position, and the exit door is in the closed position.
The housing has been extended beneath conveyor 40 to accommodate
the additional area needed for the opening of the entrance and exit
doors.
[0057] FIG. 9 illustrates an embodiment in which each of the
entrance and exit doors are implemented as two separate door
panels. The entrance door includes top panel 105 and bottom panel
110. The exit door similarly includes top panel 115 and bottom
panel 120. The top and bottom panel of each door may be slideably
moved in opposing directions, vertically in the example of FIG. 9,
to provide or inhibit access to their respective apertures.
[0058] For instance, the exit door and included panels 115 and 120
are in the closed position. To open the exit door, panel 115 is
moved vertically upward while panel 120 is moved vertically
downward. Panels 105 and 110 of the entrance door have been moved
in such a manner, exposing entrance aperture 35. To close the
entrance door, for example, panel 105 is moved downward and panel
110 is moved upward until these two structures make contact. If
described, the entrance and exit doors may be alternatively
structured so that their respective panels open and close
horizontally, or at any other angle, relative to the baggage travel
path. Alternatively, one of the apertures may be opened and closed
by a one-element door, and the other by a two-element door.
[0059] Inspection systems which utilize a single door for isolation
are also possible. For example, in FIG. 10, conveyor 50 is shown
advancing baggage 30 toward entrance aperture 35, which is located
on the top side of inspection system 200. Entrance door 45 is in
the open position, exposing entrance aperture 35. Lift 205
positions conveyor 40 near the top of the interior cavity of
housing 15. Conveyor 40 receives the baggage from conveyor 50. For
clarity, sensor system 25 has been omitted from FIG. 10.
[0060] In FIG. 11, the lift lowers conveyor 40 along with the
baggage. Once the baggage has been lowered into inspection zone 20
of the housing, entrance door 45 is advanced horizontally to seal
the isolation system, as shown in FIG. 12. Once sealed, the
inspection system may inspect the baggage in a manner similar to
that described in conjunction with other embodiments. Upon
completion of the inspection process, the process shown in FIGS. 11
and 12 may be reversed and the baggage expelled from the inspection
system. The inspection system may then be readied to receive the
next item of baggage, and the inspection process is repeated.
[0061] FIGS. 13 through 15 are side views of inspection system 250,
and collectively show a generalized example of a baggage inspection
process utilizing a top-loading inspection system. In FIG. 13,
conveyor 50 advances baggage 30 toward entrance aperture 35.
Similar to the inspection system of FIGS. 10 through 12, the
entrance aperture of inspection system 250 is also on the top side
of the system. Entrance door 45 is in the open position, exposing
entrance aperture 35. In FIG. 14, conveyor 40 receives the falling
baggage from conveyor 50. In this embodiment, no lift is necessary,
but is possible should it be desired.
[0062] Once the baggage has been received into inspection zone 20,
entrance door 45 may be advanced horizontally to seal the
inspection system, as shown in FIG. 15. If necessary, conveyor 40
may adjust the position of the baggage within the inspection zone.
Once sealed, the inspection system may inspect the baggage in a
manner similar to that described in conjunction with other
embodiments. As shown in FIG. 16, after the inspection process has
been completed, and exit door 55 is moved vertically downward to
expose exit aperture 60. The inspection system may then be readied
to receive the next item of baggage for inspection. Various
embodiment have been described, some having a single door and
aperture, others utilizing two doors and an associated two
apertures. It is to be understood that the entrance door and
aperture may be located at any just about any location on the
housing (for example, top, bottom, left side, right side, front
side, rear side). In embodiments that utilize separate exit doors,
the exit door and aperture may also be located at just about any
location on the housing, as long as such location cooperates with
the location of the entrance door and aperture. Most practical
applications utilize entrance and exit doors which open and close
either horizontally or vertically relative to the travel path of
the baggage, but these doors may alternatively be moved in almost
any orientation relative to the baggage travel path. In addition,
multiple entrance doors and apertures, multiple exit doors and
apertures, or both, are also possible and envisioned by the present
disclosure.
[0063] FIG. 17 is a flowchart showing exemplary operations for
inspecting a specimen for an item of interest. Block 140 recites
selectively operating a positioning device located within a housing
having a cavity that defines an inspection zone. Block 142 recites
selectively operating a first sealing mechanism operatively coupled
to the housing. The first sealing mechanism is selectively
positionable between open and closed positions. The open position
permits a specimen to pass through an entrance aperture and to come
into contact with the positioning device, and the closed position
seals the entrance aperture to effectively isolate the inspection
system. Block 144 recites inspecting the specimen for an item of
interest after the first sealing mechanism is positioned in the
closed position.
[0064] FIG. 18 is block diagram of system 260, which may be
implemented to control, manage, operate, and monitor, the various
components associated with inspection system 10. System 260 is
shown having a graphical user interface 265, processor 270, and
memory 275. The processor may be implemented using any suitable
computational device that provides the necessary control,
synchronization, monitoring, and data analysis of the various
systems and components associated with the inspection system.
System 260 is shown in communication with a single inspection
system, but embodiments in which system 260 is used to control
multiple inspection systems are also possible.
[0065] In general, processor 270 may be a specific or general
purpose computer such as a personal computer having an operating
system such as DOS, Windows, OS/2 or Linux; Macintosh computers;
computers having JAVA OS as the operating system; graphical
workstations such as the computers of Sun Microsystems and Silicon
Graphics, and other computers having some version of the UNIX
operating system such as AIX or SOLARIS of Sun Microsystems; or any
other known and available operating system, or any device
including, but not limited to, laptops and hand-held computers.
Graphical user interface 265 may be any suitable display device
operable with any of the computing devices described herein and may
comprise a display such as an LCD, LED, CRT, plasma monitor, and
the like.
[0066] The communication link between system 260 and the various
components of the inspection system may be implemented using any
suitable technique that supports the transfer of data and necessary
signaling for operational control of the various components (for
example, conveyors 40, 50, and 65, sensor system 25, doors 45 and
55) of the inspection system. The communication link may be
implemented using conventional communication technologies such as
UTP, Ethernet, coaxial cables, serial or parallel cables, and
optical fibers, among others. Although the use of wireless
communication technologies is possible, they are typically not
utilized since they may not provide the necessary level of security
required by many applications such as airport baggage screening
systems.
[0067] In some implementations, system 260 is physically configured
in close physical proximity to the inspection system, but system
260 may be remotely implemented if so desired. Remote
implementations may be accomplished by configuring system 260 and
the inspection system with a suitably secure network link that
comprises anything from a dedicated connection, to a local area
network (LAN), to a wide area network (WAN), to a metropolitan area
network (MAN), or even to the Internet.
[0068] The various methods and processes described herein may be
implemented in a computer-readable medium using, for example,
computer software, hardware, or some combination thereof. For a
hardware implementation, the embodiments described herein may
performed by processor 270, which may be implemented within one or
more application specific integrated circuits (ASICs), digital
signal processors (DSPs), digital signal processing devices
(DSPDs), programmable logic devices (PLDs), field programmable gate
arrays (FPGAs), processors, controllers, micro-controllers,
microprocessors, other electronic units designed to perform the
functions described herein, or a selective combination thereof.
[0069] For a software implementation, the embodiments described
herein may be implemented with separate software modules, such as
procedures, functions, and the like, each of which perform one or
more of the functions and operations described herein. The software
code can be implemented with a software application written in any
suitable programming language and may be stored in a memory unit
(for example, memory 275), and executed by a processor (for
example, processor 270). The memory unit may be implemented within
the processor or external to the processor, in which case it can be
communicatively coupled to the processor using known communication
techniques. The memory unit shown in FIG. 18 may be implemented
using any type (or combination) of suitable volatile and
non-volatile memory or storage devices including random access
memory (RAM), static random access memory (SRAM), electrically
erasable programmable read-only memory (EEPROM), erasable
programmable read-only memory (EPROM), programmable read-only
memory (PROM), read-only memory (ROM), magnetic memory, flash
memory, magnetic or optical disk, or other similar or effective
memory or data storage device.
[0070] As previously noted, a number of different door
configurations, materials, and drive mechanisms may be used in
implementing entrance doors 45 and 60. In accordance with
alternative embodiments, FIGS. 19 through 32 depict various
components of a sealing mechanism which may be utilized by any of
the inspection systems discussed herein.
[0071] FIGS. 19 through 21 are perspective views of sealing
mechanism 300 attached to inspection system 10. FIG. 22 is a front
view of the inspection system shown in FIGS. 19 through 21, but the
sliding door and associated linkage has been omitted to reveal the
underlying structures.
[0072] As shown in these figures, sealing mechanism 300 includes
flange 305 and interface 310. The interface defines entrance
aperture 35, which provides access to inspection zone 20. Motor 315
(FIG. 22) utilizes belt 317 for driving lower drive shaft 320.
Belts 325 and 330 connect the lower drive shaft to upper drive
shaft 332, which is located above the entrance aperture. Upper
brackets 335 and 340 are attached to left and right frames 345 and
350, respectively. Left linear rail 355 is shown attached to the
left frame while right linear rail 360 is shown attached to the
right frame. The length of these rails is typically twice the
height of the aperture defined by interface 310. This permits
sliding door 425 to completely seal entrance aperture 35 when
closed, and to fully retract when open.
[0073] Interface 310 is shown protruding from flange 305. It is to
be understood that the length of the protrusion of flange 305 is
not to be confused with, for example, the considerably longer
wave-guide tunnel extensions which are commonly used in various
types of explosive detection systems, In an embodiment, the
interface need only protrude from flange 305 to the extent
necessary to accommodate the various door linkage and drive
components. Using a conventional passenger baggage inspection
system as an example, the interface protrudes from the flange a
distance of only a few inches (4-9 inches being typical). This
protrusion is considerably shorter than a typical wave-guide
tunnel, which can have a length of 24-48 inches, or more, that is
required by such passenger baggage inspection systems. If desired,
the protrusion of interface 310 may be further minimized by
alternatively locating the door linkage and drive components on
front and rear sides 442 and 445 of the inspection system.
[0074] Upper brackets 335 and 340 may each have an attached cam
latch 365. The cam latches facilitate closure of the sliding door,
as will be described in more detail herein. An exposed edge of
interface 310 is shown having seal 380. The seal is typically used
to facilitate contact with sliding door 425, and may be formed from
any suitable material which cooperates with the door to provide the
necessary isolation of the inspection system. Door stops 385 and
390 are shown attached to lower brackets 395 and 400.
[0075] The type of materials depends on the type of sensor system
utilized, and the type and amount of isolation desired. For
example, crushable conductive material, such as copper or aluminum,
may be used as the seal in an inspection system which contains a QR
sensor. Alternatively, the seal may be constructed of foam or
rubber whenever X-ray based sensor systems are utilized in the
inspection system. Materials for the seal may include high
conductivity metals (electromagnetic shielding), high-z materials
for radiological shielding, and metal/composite meta-materials to
minimize reflection at high frequency (microwave, mmwave).
Exemplary metals include, but are not limited to, copper, gold,
silver, nickel, etc. Physical structures include various
embodiments of a highly conductive and mechanically sound
environmental sealing surface. The seal materials should be
engineered to maintain tolerance under repeated cycling.
[0076] If desired, the left and right frames and included
components may be secured to base 405. Optional stop buttons 415
and 420 are shown on the upper portion of frame 345. These stop
buttons are conveniently located near the entrance aperture and may
be used to manually halt operation of the sealing mechanism in, for
example, emergency situations. Although inspection system 10 is
shown with two sealing mechanisms 300, only one is required. One
sealing mechanism is shown positioned at the front side of the
system, and the other is positioned at the rear side and is
partially hidden. Operation of sealing mechanism 300 will be
described after various components of the mechanism, which are
depicted in FIGS. 23-32, have been discussed.
[0077] Referring now to FIG. 23, a close-up view of the upper left
side of sealing mechanism 300 is shown. The door and associated
linkage have been omitted from this figure to reveal the underlying
components. In this figure, linear rail 355 is attached to left
frame 345, and cam latch 365 is attached to the bottom side of
bracket 335, adjacent to doorstop 370. The cam latch is sized to
receive a cam that is in communication with the sliding door.
During operation, the cam engages the cam latch, causing the door
to move inwardly as it nears the end of its travel path. This
causes an interior portion of the door to contact seal 380,
effectively isolating inspection system 10. This aspect will be
described in more detail in conjunction with FIGS. 26 through
29.
[0078] FIG. 24 is a perspective view of door linkage components
that may be implemented in sealing mechanism 300. The linkage shown
is for the left side of entrance aperture 35, but the right side
linkage essentially mirrors the left side linkage. Carriage link
450 is attached to upper control arm 455 and lower control arm 460.
The upper control arm is shown in more detail in FIG. 31. Referring
still to FIG. 24, the upper control arm is pivotally attached to
clamp 465, which is secured to belt 325. Belt 325 is a transport
device that may be used to open and close door 425. During
operation, the door may be closed by moving belt 325 upward.
Conversely, the door may be opened by moving belt 325 downward.
[0079] Carriage link 450 is also attached to upper carriage 470,
which sideably engages linear rail 355. The carriage link is
similarly attached to lower carriage 475, which also sideably
engages linear rail 355. Turnbuckle 480 is pivotally attached to
lower control arm 460, and connects clamp 465 and attached upper
control arm 455 with lower control arm 460. Carriage spring 477 is
attached to bracket 479.
[0080] FIG. 25 is a close-up view of the upper left side of sealing
mechanism 300. In this figure, door 425 is shown secured to upper
control arm 455. The door is in the closed position, contacting
seal 380. Cam spring 505 is attached to bracket 510.
[0081] FIG. 26 is a close-up isometric view of the top portion of
the left-side door linkage, from the viewpoint of looking away from
the housing of the inspection system. FIG. 27, on the other hand,
is a close-up view of the same top portion of the door linkage, but
from the viewpoint of looking toward the housing of the inspection
system. To permit a clearer view of the door linkage, door 425 has
been omitted from these figures. Cam 500 is shown positioned within
a recess formed in an upper portion of carriage link 450. The cam
pivots within the recess of the carriage link, and contains an open
end which is sized and positioned to engage cam latch 365 (not
shown in this figure). Referring ahead to FIG. 30, a more detailed
view of cam 500 is shown. The cam is shown having bearing 515,
which facilitates pivoting of this component within carriage link
450. The cam has cam spring 505 which, in FIG. 27, is shown
attached to bracket 510.
[0082] FIG. 28 is a close-up view of the upper left side of sealing
mechanism 300. The upper control arm and carriage link have been
omitted to show the relative positioning of cam 500 and cam latch
365 when door 425 is in the fully closed position. In this figure,
the cam is fully engaged with the cam latch, causing an interior
portion of door 425 to contact seal 380.
[0083] FIG. 29 is essentially the same view as FIG. 28, but in FIG.
29 the door has been moved downward. Cam 500 no longer engages the
cam latch, permitting the door to move outward and out of contact
with seal 380. Since the door is no longer in contact with the
seal, the door can freely continue its downward motion, providing
access to entrance aperture 35.
[0084] FIG. 31 is a close-up view of upper control arm 455, which
is shown having first and second pins 485 and 490. First pin 485
secures the top portion of carriage link 450 to the upper control
arm. Second pin 490 pivotally attaches door 425 to the upper
control arm, while third pin 495 attaches the upper control arm to
clamp 465. The structure of lower control arm 460 is essentially
the same as upper control arm 455.
[0085] FIG. 32 shows door 425 having four attachment bushings 520
located on inner surface 525. These bushings may be used to mount
the door to the door linkage of sealing mechanism 300.
Specifically, each of the four bushings may be pivotally attached
to an associated control arm using second pin 490. The inner
surface of door 425 may be planar or substantially planar. In some
embodiments, the inner surface may be convex to further enhance the
contact seal of the inner surface of the door with seal 380. Door
425 may be constructed using any of the door materials discussed
above in conjunction with other embodiments.
[0086] Referring back to FIGS. 19 thorough 22, operation of sealing
mechanism 300 in accordance with an embodiment of the invention
will now be described. In FIG. 19, door 425 is in the fully open
position, exposing entrance aperture 35. Internal conveyor 40 has
positioned baggage 30 within inspection zone 20 of the inspection
system. Again, the inspection system may receive baggage 30 from a
cooperating baggage transport system, such as a baggage conveyor
(not shown in this figure).
[0087] In FIG. 20, motor 315 drives lower drive shaft 320 in a
first direction, causing belts 325 and 330 to move in a
counter-clockwise direction about upper and lower drive shafts 332
and 320. Door 425 is effectively connected to belts 325 and 330 via
door linkage components such as upper control arm 455, carriage
link 450, and clamp 465. The movement of the belts cause door 425
to move upward, as guided by linear rails 355 and 360. As shown in
FIG. 20, the door partially conceals entrance aperture 35. As motor
315 continues to drive the lower drive shaft in this direction, the
door will continue to move upward relative to the entrance
aperture.
[0088] As door 425 nears the end of its travel path, cam 500
engages cam latches 365 on both the right and left sides of the
entrance aperture 35, causing the door to move inwardly in addition
to its upward motion. Again, the right (partially hidden) side of
the entrance aperture includes essentially the same door linkage
components as that illustrated on the left side of the entrance
aperture. As the door moves inward, a portion of its interior
surface contacts seal 380. As each cam 500 fully engages its
associated cam latch, the door comes to rest at its upper travel
point. The door is now closed, effectively isolating the inspection
system 10. Baggage 30 may now be inspected using, for example, any
of the various inspection techniques described herein.
[0089] Opening of door 425 may be accomplished by essentially
reversing the just-described door closing process. For instance,
the door may be opened by motor 315 driving lower drive shaft 320
in a second direction, causing belts 325 and 330 to move in a
clockwise direction about upper and lower drive shafts 332 and 320.
At the initial stages of the opening process, each cam 500 will
disengage its associated cam latch 365, in both the right and left
side door linkage. At about the same time, the cams will rotate out
of their locked position within their respective cam latches,
permitting the door to move outward and out of contact with seal
380. The door continues to move downward until the door stops in
the open position, as shown in FIG. 19. The inspected baggage 30
may then be removed, and this process repeated for additional
baggage items.
[0090] While the invention has been described in detail with
reference to disclosed embodiments, various modifications within
the scope of the invention will be apparent to those of ordinary
skill in this technological field. It is to be appreciated that
features described with respect to one embodiment typically may be
applied to other embodiments. Therefore, the invention properly is
to be construed only with reference to the claims.
* * * * *