US 8,571,829 B2 · Detecting objects in shipping containers by vibration spectral analysis

Abstract

Objects in a cargo shipping container are detected by measuring vibration resonant frequency peaks of the container. The mass of an object on the floor of the container effects the vibration resonance of the container, enabling the object to be detected. A vibration source and a plurality of accelerometers are either attached to the steel structure of the container, or are disposed on a supporting structure, such as a cargo crane or lift, so that they contact the container. The vibration source causes the container to vibrate, and the accelerometers detect the vibration resonance of the container. A mismatch between a cargo manifest and an observed cargo, or detection of an object having relatively high mass, e.g., due to lead shielding, can justify a manual inspection. The process uses synchronous processing to achieve the sensitivity needed, is unobtrusive, and does not slow the flow of cargo through a facility.

Claims30

Dependent claims

A method for using a vibration analysis to detect an object within a freight shipping container, based on a mass of the object, comprising the steps of:

(a) while the container is being supported, using a vibration source for exciting the container to vibrate;
(b) coupling a plurality of vibration sensors to the container at a plurality of spaced-apart locations;
(c) using the plurality of vibration sensors to sense resonant vibrations of the container due to the vibration source, wherein an arrangement of the spaced-apart locations of vibration sensors can effectively sense the resonant vibrations of two or more classes of container;
(d) sensing resonant vibrations of the container in response to the excitation of the container by the vibration source;
and
(e) using a computing device, identifying a location of one or more objects disposed within the container by at least analyzing the resonant vibrations of the container that were sensed at one or more locations of the plurality of spaced apart locations, so as to detect a resonant vibration response of the container caused by a presence of the object disposed within the container, the response being a function of the object's mass.

3 more elements

A system for using vibration analysis to detect an object within a freight shipping container, based on a mass of the object, comprising:

(a) a vibration source that is configured to be coupled to the container;
and
(b) a plurality of vibration sensors that are positioned to couple with the container at a plurality of spaced-apart locations to sense resonant vibrations of the container due to the vibration source, wherein an arrangement of the spaced-apart locations of vibration sensors effectively senses the resonant vibrations of two or more classes of containers that pass through a facility,
(c) a computing device that is coupled to the vibration source and to the plurality of vibration sensors, the computing device including:
(i) a memory in which machine readable and executable software instructions are stored;
and
(ii) a processor that is coupled to the memory, the processor executing the software instructions to carry out a plurality of functions, including:
(A) controlling the vibration source to excite the container to vibrate;
(B) receiving vibration sensor output signals from the plurality of vibration sensors;
(C) analyzing the vibration sensor output signals to determine resonant vibrations of the container so as to detect an object disposed in the container as a function of a mass of the object, based upon an effect of the object on the resonant vibrations of the container, and to identify a location of the object disposed in the container based on the effect of the object upon the resonant vibrations of the container;
and
(D) providing an indication of an object detected in the container

9 more elements

A method, comprising the steps of:

(a) while a container is being supported, using a vibration source for exciting the container to vibrate;
(b) coupling a plurality of vibration sensors to the container at a plurality of spaced-apart locations;
(c) using the plurality of vibration sensors to sense the resonant vibrations of the container due to the vibration source;
wherein an arrangement of the spaced-apart locations of vibration sensors can effectively sense the resonant vibrations of the two or more classes of containers;
(d) using a computing device, determining a vibration signature for the container based upon the resonant vibrations of the container that were sensed;
and
(e) using the computing device, detecting a presence of one or more objects within the container by comparing the vibration signature determined for the container with reference vibration signature data determined for a similar empty container, to determine a location of the one or more objects within the container.

4 more elements

A system, comprising:

(a) a container;
(b) a vibration source that is configured to be coupled to the container;
and
(c) a plurality of vibration sensors that are positioned to couple with the container at a plurality of spaced-apart locations to sense the resonant vibrations due to the vibration source, wherein an arrangement of the spaced-apart locations of vibration sensors is optimal for maximum sensitivity for the resonant vibrations of two or more different classes of container that pass through a facility
(d) a computing device that is coupled to the vibration source and to the plurality of vibration sensors, the computing device including:
(i) a memory in which machine readable and executable software instructions are stored;
and
(ii) a processor that is coupled to the memory, the processor executing the software instructions to carry out a plurality of functions, including:
(A) controlling the vibration source to excite the container to vibrate;
(B) sensing resonant vibrations of the container using the plurality of vibration sensors;
(C) analyzing the sensed resonant vibrations of the container to determine a vibration signature for the container;
and
(D) detecting a presence of one or more objects within the container by at least comparing the vibration signature determined for the container with reference vibration signature data determined for a similar empty container, to determine a location of the one or more objects within the container.

10 more elements

Dependencies are inferred from the claim text.

Detecting objects in shipping containers by vibration spectral analysis

Life of this patent

Detecting objects in shipping containers by vibration spectral analysis

Life of this patent

Abstract

Claims30