GB2604596A

GB2604596A - Detection and identification of objects in a waste load

Info

Publication number: GB2604596A
Application number: GB2103123.2A
Authority: GB
Inventors: Andrew Walker David
Original assignee: Vigilant Scanning Ltd
Current assignee: Vigilant Scanning Ltd
Priority date: 2021-03-05
Filing date: 2021-03-05
Publication date: 2022-09-14
Also published as: WO2022185274A1; GB202103123D0

Abstract

A system for detection and identification of objects in a waste load comprising: a scanning module comprising a first laser and a sensor configured to generate LIDAR data based on a surface of the waste load. A second laser configured to generate a laser pulse towards a first location on the surface of a waste load, the laser configured to excite the waste load and generate a secondary wave from the excitation. A third laser configured to obtain a measurement of the characteristics of the secondary was at a second location on the surface of the waste load. A processing unit is configured to generate a 3D model of the waste load based on the LIDAR data and determine the density of an object located within the 3d model based on the measurement of the third laser. The object being preferably identified by a comparison of the determined density with predetermined data. The system may include a laser induced breakdown spectroscopy (LIBS) module configured to conduct spectral analysis of a third location, this being used by the processing unit to aid determination of the object.

Description

DETECTION AND IDENTIFICATION OF OBJECTS IN A WASTE LOAD

The present invention relates generally to a system and method for detection and identification of objects in a waste load and finds particular, although not exclusive, utility in detecting and identifying the presence of lithium-ion batteries in a waste load.

With the growing prevalence of lithium-ion battery technology, billions of such batteries are incorrectly disposed of globally every year. While accidents are less common during consumer use, processing objects, such as hidden batteries, along with general waste can lead to fires at waste and recycling sites, particularly when the batteries are punctured in the proximity of combustible waste materials. Existing waste sorting procedures to identify objects, such as batteries, include manual processing by hand, which can be inefficient, expensive and time-consuming.

In a first aspect, the invention provides a system for detection and identification of objects in a waste load, the system comprising: a scanning module, comprising a first laser and a sensor, wherein the scanning module is configured to generate TAD AR data based on a surface of the waste load; a second laser configured to emit a laser pulse towards a first location on the surface of the waste load, the laser pulse configured to excite the waste load and to generate a secondary wave based on said excitation; a third laser configured to obtain a measurement of the characteristics of the secondary wave at a second location on the surface of the waste load; and a processing unit configured to: generate a three-dimensional model of the waste load based on the LiDAR data; and determine the density of an object located within the three-dimensional model based on the measurement of the third laser.

In this way, the objects may be automatically detected and identified within a waste load without the need of human intervention. Propagation of the secondary wave through the waste load between the first location and second location may be determined by shearing of the material therebetween. The three-dimensional model may provide for an efficient method of accurately locating the position of the object. With reference to this three-dimensional model, the process of removal of objects from the waste load may improve upon existing procedures. Additionally, or alternatively, objects may be accurately targeted in-situ and rendered non-hazardous prior to further processing of the waste load. Objects of interest may include lithium-ion batteries, batteries of alternative composition, gas canisters and/or flares.

The waste load may be situated within a container, for example a waste truck. Alternatively, the waste load may be situated on a surface, for example a conveyor belt or external tipping area.

The first laser, second laser and third laser may all be distinct physical components. Alternatively, the first laser, second laser and third laser may be the same physical component, adapted to function in each of the modes described.

The sensor may be configured to detect light emitted by the first laser and reflected from a surface of the waste load. The sensor may be configured to detect a particular wavelength of light and may be, for example, an infrared camera.

LiDAR data refers to datt collected via a method of measuring physical distances with the first laser and sensor. the first laser and sensor may be configured to generate time-of-flight (TOE) LiDAR data, where the first laser emits a pulse which is deflected by a mirror towards the surface of the waste load, and the time taken for the pulse to reflect from the surface and return to the sensor is measured.

Alternatively, or additionally, the first laser and sensor may he configured to generate phase-based LiDAR data, where the first laser emits a phase modulated beam. The sensor then measures a phase of a reflected beam and a processing unit is configured to determine the distance to the surface based on the difference in phase between the emitted phase modulated beam and the corresponding reflected phase modulated beam.

Whether TOF or phased-based LiDAR data is generated, a digital evaluation model (DEM) may be generated by the processing unit to form the three-dimensional model.

The surface of the waste load may be a surface proximal to the system, for example a top surface of the waste load.

The second laser may be configured with a wavelength, pulse duration and pulse energy. The pulse energy may be configured to excite the waste load at the first location on the surface of the waste load, when the laser pulse is partially or wholly absorbed by the surface of the waste load. The excitation may comprise an ablative interaction which induces a thermal shock in the surface of the waste load, which may cause a generated secondary wave, or surface acoustic wave to emanate from the first location across the waste load.

The third laser may be configured with a wavelength, pulse duration and pulse energy configured to enable measurement of the waste load at the second location, and thereby measure the characteristics of the secondary wave emanating from the first location. Such characteristics may include amplitude, phase and/or frequency. Since the propagation of the secondary wave may be dependent upon the materials present between the first and second locations, the amplitude, phase and/or frequency of the secondary wave may be indicative of the arrangement and density of objects present in the waste load between the first and second locations.

The first and second locations may be spaced apart on the surface of the waste load. Alternatively, the first and second locations may be at approximately the same point on the surface of the waste load.

The processing unit may be part of the same physical system as the other components. Alternatively, the processing unit may be connected to the other components, and for example may be a desktop computer, laptop or other computer receiving and analysing data collected by the rest of the system.

The determined density of the object may be shown graphically within the three- ] 5 dimensional model, for example by assigning a hue, saturation and/or luminosity to voxds and/or pixels within the three-dimensional model according to their determined density.

The processing unit may be further configured to identify the object by comparing its determined density against a predetermined set of data.

Tn this way, the system may provide an indication of the material, composition and/or type of the object identified. 'To detect objects comprising a combination of known materials, item signatures may be used. Item signatures may comprise Boolean expressions that aim to confitm whether all of the component materials of an object are present and have been detected in the same vicinity. This infotmation may assist a user in distinguishing between different categories of object, for example between batteries of different compositions, gas canisters and/or flares.

The predetermined set of data may be stored locally, or may be stored remotely for access by the system. The predetermined set of data may be updated by the determination of objects and/or user input. For example, a previously unidentified material or object may be identified by manual user input and this data may then be included in the predetermined set of data, to enable the identification of other objects located within the three-dimensional model.

The system may further comprise a laser induced breakdown spectroscopy (LIBS) module configured to conduct spectral analysis of a third location on the surface of the waste load, and wherein the processing unit is further configured to use the spectral analysis to aid in determination of the object.

Tn this way, the processing unit may be provided with additional information relating to the composition of the surface of the waste load. Accordingly, the accuracy of determination of the object may be improved.

The laser induced breakdown spectroscopy (JIBS) component may use a focused laser pulse to ablate a location on the surface of the waste load. The second laser may be distinct from, or form a part of the LTBS module/component. The ablation of the surface may lead to the initiation of a high temperature plasma above the surface, and a rapid expansion of the plasma into the ambient medium surrounding the surface. As the plasma cools, emitted light may be detected by the LIT3S component, which may be spectrally analysed. The discrete spectral peaks of the emitted light may then be associated with the chemical composition of the surface of the waste load.

The scanning module may be configured to operate within a range of 900 nanometres to 1700 nanomares.

In this way, the system may be calibrated for computer vision applications in the short-wave infrared spectrum (SWIR).

The processing unit may be further configured to determine the electrical charge of an object from the third laser measurement.

in this way, the electrical charge of objects such as batteries present in the waste load may be determined.

The determination of electrical charge may be achieved via further interrogation of the third laser measurement of the secondary wave.

At least one of the first laser, the second laser and the third laser may be arranged to project in a 6-point array.

in this way, the system may simultaneously measure 6 points, thereby allowing for a wide field of view.

The 6-point array may be approximately imn in area at the surface of the waste load.

The system may further comprise a display to show a visual representation of the three-dimensional model and object located therein.

In this way, a user of the system may be assisted in identifying objects of interest within the three-dimensional model.

The display may be further configured to show projections and/or tomographic cross-sections of the three-dimensional model.

Tn a second aspect, the invention provides a method of detecting and identifying objects in a waste load, the method comprising the steps of: providing the system of any preceding claim; using the scanning module to measure the physical position of a surface of the waste load to generate HD AR data; emitting a laser pulse with the second laser towards a first location on the surface of the waste load, the laser pulse configured to generate a secondary wave; using the third laser to obtain a measurement of the characteristics of the secondary wave at a second location on the surface of the waste load; and using the processing unit: generating a three-dimensional model of the waste load based on the LiDAR. data; and determining the density of an object located within the three-dimensional model based on the laser measurement.

The above and other characteristics, features and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention. This description is given for the sake of example only, without limiting the scope of the invention. The reference figures quoted below refer to the attached drawings.

Figure 1 is an interferometer for a system for detection and identification of objects in a waste load.

Figure 2 shows banks of beam splitting minor drives.

The present invention will be described with respect to certain drawings but the invention is not limited thereto but only by the claims. The drawings described are only schematic and are non-limiting. Each drawing may not include all of the features of the invention and therefore should not necessarily be considered to be an embodiment of the invention. In the drawings, the size of some of the elements may he exaggerated and not drawn to scale for illustrative purposes. The dimensions and the relative dimensions do not correspond to actual reductions to practice of the invention.

Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequence, either temporally, spatially, in ranking or in any other manner. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that operation is capable in other sequences than described or illustrated herein, likewise, method steps described or chimed in a particular sequence may be understood to operate in a different sequence.

Moreover, the terms top, bottom, over, under and the like in the description and the claims are used for descriptive purposes and not necessarily for describing relative positions. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that operation is capable in other orientations than described or illustrated herein.

It is to be noticed that the term "comprising", used in the claims, should not be interpreted as being restricted to the means listed thereafter; it does not exclude other elements or steps. It is thus to be interpreted as specifying the presence of the stated features, integers, steps or components as referred to, but does not preclude the presence or addition of one or more other features, integers, steps or components, or groups thereof. Thus, the scope of the expression "a device comprising means A and B" should not be limited to devices consisting only of components A and B. It means that with respect to the present invention, the only relevant components of the device are A and B. Similarly, it is to be noticed that the term "connected", used in the description, should not be interpreted as being restricted to direct connections only. Thus, the scope of the expression "a device A connected to a device B" should not be limited to devices or systems wherein an output of device A is directly connected to an input of device B. It means that there exists a path between an output of A and an input of B which may be a path including other devices or means. "Connected" may mean that two or more elements are either in direct physical or electrical contact, or that two or more elements are not in direct contact with each other but yet still co-operate or interact with each other.

For instance, wireless connectivity is contemplated.

Reference throughout this specification to "an embodiment" or "an aspect" means that a particular feature, structure or characteristic described in connection with the embodiment or aspect is included in at least one embodiment or aspect of the present invention. Thus, appearances of the phrases "in one embodiment", "in an embodiment", or "in an aspect" in various places throughout this specification are not necessarily all referring to the same embodiment or aspect, but may refer to different embodiments or aspects. Furthermore, the particular features, structures or characteristics of any one embodiment or aspect of the invention may be combined in any suitable manner with any other particular feature, structure or characteristic of another embodiment or aspect of the invention, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments Or aspects.

Similarly, it should be appreciated that in the description various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Moreover, the description of any individual drawing or aspect should not necessarily be considered to be an embodiment of the invention. Rather, as the following claims reflect, inventive aspects lie in fewer than all features of a single foregoing disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this invention.

Furthermore, while some embodiments described herein include some features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and fOrif 1 yet further embodiments, as will be understood by those skilled in the art For example, in the following claims, any of the claimed embodiments can be used in any combination.

In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the invention may be practised without these specific details. In other instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this

description.

In the discussion of the invention, unless stated to the contrary, the disclosure of alternative values for the upper or lower limit of the permitted range of a parameter, coupled with an indication that one of said values is more highly preferred than the other, is to be construed as an implied statement that each intermediate value of said parameter, lying between the more preferred and the less preferred of said alternatives, is itself preferred to said less preferred value and also to each value lying between said less preferred value and said intermediate value.

The use of the term "at least one" may mean only one in certain circumstances.

The use of the term "any" may mean "all" and/or "each" in certain circumstances.

The principles of the invent on will now be described by a detailed description of at least one drawing relating to exemplary features. Tt is clear that other arrangements can be configured according to the knowledge of persons skilled in the art without departing from the underlying concept or technical teaching, the invention being limited only by the terms of the appended claims.

Figure 1 is a schematic of an interferometer 20 which comprises a beam splitter 10. Light emitted from a scanning laser 30 passes through a quarter-wave plate 35 before reaching a nonpolarizing splitter 40. Light reflected from the nonpolarizing splitter 40 travels along a reference path, passes through a polarizer 50 and is received by a photodetector 60. The detected light is then measured by a counter 70 and balancing mechanism $O. Light transmitted through the nonpolarizing splitter travels towards the beam splitter 10. Light reflected from the beam splitter 10 travels towards and is reflected back from a reference reflector 90. Light transmitted through the beam splitter travels towards and is reflected back from a moving reflector 100. The moving reflector 100 may be a surface of a waste load comprising targets of interest, such as lithium-ion batteries. light reflected back from the reference reflector 90 and moving reflector 100 is once again transmitted through and reflected from the beam splitter 10, after which it travels along a measurement path. The measurement path beam then passes through a final polarizer 110 and is received by a photodetector 120. 'fhe detected light is then measured by a counter 130 and the balancing mechanism 80. Comparison of the reference path and measurement path enable determination of the nature of the movement of the moving reflector 100. Such determination may include characteristics of a generated secondary wave, which may in turn enable determination and identification of the density of the moving reflector 100.

Figure 2 shows banks of beam splitting mirror drives. Light emitted from laser 200 passes through an initial beam splitter 210, where it is split into a reference beam and a test beam. The reference beam is reflected from a y axis multiple mirror complex 220, before passing towards a final beam splitter 230. The test beam passes through a Bragg cell 240, where its frequency is shifted, before passing towards a test beam splitter 250. The transmitted test beam is reflected from a moving target 260, where its frequency is shifted again due to the target's movement. The movement of the target 260 may be indicative of a secondary wave generated on the surface of the target 260. After passing Lack through the test beam splitter 250, the test beam passes through the final beam split-ter 230. The reference beam and the test beam are then both received and measured by a photo detector 270. The difference in phase between the two beams may then be used to determine the nature and amplitude of the target's movement, and therefore the characteristics of a generated secondary wave in the target. This enables determination of the characteristics of the secondary wave, which may in turn enable determination and identification of the density and configuration of the target 260.

Claims

CLAIMS1. A system for detection and identification of objects in a waste load, the system comprising: a scanning module, comprising a first laser and a sensor, wherein the scanning module is configured to generate LiDAR data based on a surface of the waste load; a second laser configured to emit a laser pulse towards a first location on the surface of the waste load, the laser pulse configured to excite the waste load and to generate a secondary wave based on said excitation; a third laser configured to obtain a measurement of the characteristics of the secondary wave at a second location on the surface of the waste load; and a processing unit configured to: generate a three-dimensional model of the waste load based on the LOAR data; and determine the density of an object located within the three-dimensional model based on the measurement of the third laser.
2. The system of claim 1, wherein the processing unit is further configured to identify the object by comparing its determined density against a predetermined set of data.
3. The system of either one of claims 1 and 2, further comprising a laser induced breakdown spectroscopy (LIBS) module configured to conduct spectral analysis of a third location on the surface of the waste load, and wherein the processing unit is further configured to use the spectral analysis to aid in determination of the object.
4. The system of any preceding claim, wherein the scanning module is configured to operate within a range of 900 nanometres to 1700 nanonactres.The system of any preceding claim, wherein the processing unit is further configured to determine the electrical charge of an object from the third laser measurement.The system of any preceding claim, wherein at least one of the first laser, the second laser and the third laser are arranged to project in a 6-point array.The system of any preceding claim, further comprising a display to show a visual representation of the three-dimensional model and object located therein.A method of detecting and identifying objects in a waste load, the method comprising the steps of: providing the system of any preceding claim; using the scanning module to measure the physical position of a surface of the waste load to generate LID AR data; emitting a laser pulse with the second laser towards a first location on the surface of the waste load, the laser pulse configured to generate a secondary wave; using the third laser to obtain a measurement of the characteristics of the secondary wave at a second location on the surface of the waste load; and using the processing unit: generating a three-dimensional model of the waste load based on the LiDAR data; and detennining the density of an object located within the three-dimensional model based on the laser measurement. 3. 6. 7. 8.