Method for monitoring tires with a size exceeding 30 inches by video

Abstract

The solution proposed by the present invention includes a method for monitoring the tires of a transport and excavation vehicle in a mining site using a tire handling device, where the tires are equipped with radio frequency identification tags and physical parameter sensors, and the method also uses a database containing the identifier of the vehicle, the identifier of the tire, the identifier of the sensor, and the position of the tire on the axle assembly.

Description

Technical Field

[0001] The present invention relates to the field of fleet management, and more particularly to the tires of such vehicles. More specifically, it is applicable to but not limited to the field of civil engineering vehicles. Background Art

[0002] For example, such vehicles are used in open-pit mining sites to transport materials with a load exceeding 350 tons mined from quarries. Therefore, the size of the tires must be adjusted such that the overall diameter must exceed 4 meters, and each tire weighs 5 tons.

[0003] For example, such a tire is designated as type 59 / 80R63 according to the standards of the European Tyre and Rim Technical Organization (ETRTO), with an inflation pressure of 650 kPa. For such a tire, the nominal tread width is 59 inches, the height of the tire sidewall is 80% of its nominal width, and the tire is intended to be mounted on a wheel with a diameter of 63 inches. These vehicles also have tires of other sizes with diameters ranging from 49 inches to 57 inches.

[0004] The size and weight of these tires require dedicated handling equipment to perform installation and removal operations to replace tires or swap tires from one axle to another.

[0005] Transport vehicles in mining sites have a configuration of two to four axles with single or double seats according to their intended use. Loaders equipped with buckets for loading skips are included among the transport vehicles.

[0006] Mining involves extracting a large enough quantity of ore (i.e., rock from the earth's crust containing useful minerals or metals) to justify the extraction.

[0007] The transport stage in mining operations is crucial for its economic profitability. Vehicles (dump trucks) typically operate continuously to achieve maximum productivity by moving the largest volume of crushed stone to be processed by mineral processing.

[0008] The management of the tires of a fleet includes: monitoring the inflation pressure, temperature, and wear using a predictive maintenance method to predict tire-related failures and avoid vehicle downtime to maximize the service life.

[0009] Tire wear is another performance aspect related to inflation pressure control. For example, too low a pressure (20% lower) can reduce the tire life by approximately 27%. Conversely, in the case of a 20% overpressure, the service life is reduced by approximately 12%.

[0010] Therefore, the expectations of mining customers are to ensure the safety of personnel and equipment by controlling tire usage, productivity must not be affected by product failures, and finally, the service life of the tires must be as long as possible.

[0011] To manage the vehicle fleet, the operator manually records which vehicle includes which tire and at which location. Therefore, when changing a tire, the operator must also manually replace the identifier of the tire to be replaced with the identifier of the replacement tire and the identifier of the location on the vehicle where the replacement is made. The operator further records the identifier of the vehicle for which the tire has been replaced.

[0012] The operator writes down these observed changes on the vehicle. Then, the database administrator manually updates the database by entering different identifiers. In addition, if the vehicle has a tire monitoring (e.g., tire pressure) system, the data in this system also needs to be updated. SUMMARY OF THE INVENTION

[0013] The object of the present invention is to provide a method for simplifying the tire management of transport vehicles in a mining site during tire mounting and dismounting operations.

[0014] The solution proposed by the present invention includes a method for monitoring the tires of a vehicle transporting excavated materials in a mining site by using tire handling equipment, the tires being equipped with radio frequency identification tags and physical parameter sensors; the method also uses a database containing the identifier of the vehicle, the identifier of the tire, the identifier of the sensor, and the position of the tire on the axle, and the method includes the following steps:

[0015] a. The handling equipment receives an instruction containing the position of the tire to be replaced on the transport vehicle.

[0016] b. The handling equipment identifies the transport vehicle by means of a video acquisition and processing system, the vehicle being equipped with a visual identifier capable of being detected.

[0017] c. The handling equipment activates the detection of the tire to be replaced on the vehicle through a radio frequency device.

[0018] d. The handling equipment activates the detection of the axle and the detection of the position of the tire on the axle of the vehicle by means of a video acquisition and processing system.

[0019] e. The handling equipment replaces the tire to be replaced with a replacement tire.

[0020] f. The database is updated using the identifiers of the vehicle and the replacement tire and the position of the replacement tire on the axle.

[0021] The present invention proposes to use a method based on an industrial vision system connected to a database to manage the monitoring of the tires of transport excavation vehicles in a mining site.

[0022] Industrial vision includes automating the task of controlling and monitoring tire information by implementing a process capable of analyzing, processing, and understanding one or more images captured by a video acquisition system.

[0023] For example, when replacing a tire after a flat tire or any other damage occurs to a transport vehicle, the defunct tire must be replaced with a new tire or a used tire with remaining driving potential. The process must be able to track the flow of relevant information in the following aspects: the identification of the vehicle and the associated axles, the identification of the position on the axle, and the physical parameters of the pressure and temperature levels of the relevant tire.

[0024] Another example is swapping a tire from the front axle to the rear axle, which involves the installation and removal of tires on a transport vehicle.

[0025] Tire monitoring not only involves the traceability of tires but also the monitoring of the physical parameters of tires (e.g., inflation pressure and / or temperature).

[0026] In any case, the management of tire monitoring lies in always reliably knowing the position of the tire and the position of the sensors for measuring the relevant physical parameters.

[0027] For this purpose, each tire is equipped with a radio frequency identification (RFID, radio fréquence) tag and a sensor for measuring physical parameters, which also has a unique identifier. These devices are attached to the inside of the tire.

[0028] The RFID tag on the tire is preferably passive and operates in a read-only manner. The RFID tag includes an antenna designed to operate in a given frequency band and connected to an electronic chip that stores data. The information capacity of the RFID tag is generally 2 kB, but most only contain an identification number of 96 bits or 128 bits. Then an electromagnetic signal is sent to the RFID tag, which enables the activation of the RFID chip and the reading of the information contained in the RFID tag.

[0029] The reader sends a specific polling signal for the tag response. One of the simplest possible responses is to return a digital ID, for example, using the 96-bit EPC-96 standard.

[0030] The present invention also provides a method implemented according to a device (D), the device (D) comprising: a video acquisition and processing system having at least one camera, the at least one camera optionally having suitable lighting to identify a vehicle provided with a visual identifier that can be detected by the image acquisition and processing system; reading means for reading the identification tags of the sensors and the tires; calculation and image processing means for detecting the axles and the position of the tires on the axles; and a database that associates the identifier of the tire, the identifier of the vehicle on which the tire is installed, and the position on the axle.

[0031] The industrial vision device is installed on the handling equipment. Specifically, at the front of the handling equipment located between the gripping forks of the tire, the camera is fixed in such a way that it can take pictures in the space defined by the diameter of the rim along the moving direction.

[0032] The industrial vision system is based on image processing applications. The objectives of these applications can be of different types:

[0033] - Detecting the presence or absence of an object; for example, in order to identify a vehicle, a visual identifier attached to the transport vehicle at the mining site enables the vehicle to be detected;

[0034] - Calculating the characteristics of one or more elements of the image; for example, in order to determine the action of the handling equipment, it is determined whether there is a tire between the gripping forks of the handling equipment in a series of images or sequences;

[0035] - In any case, starting from the initial image, the idea is to extract information from it; for this purpose, it is used as "software bricks (briques logicielles)" through combination and connection operators; these techniques form the basis of the industrial vision system.

[0036] In the context of industrial vision, image processing occurs after the acquisition and digitization stages, providing an image conversion and calculation part to enable subsequent interpretation of the processed image.

[0037] To understand image processing, one must first understand what an image is. The methods and conditions for the acquisition and digitization of the processed image largely determine the operations that must be performed to extract information. In fact, many parameters are taken into account, and the main parameters are:

[0038] - The acquisition resolution and coding method used during digitization, which determine the accuracy of any size measurement;

[0039] - The optical settings used (including focus and depth of field), which determine, for example, the sharpness of the image;

[0040] - The lighting conditions, which determine the partial variability of the processed image;

[0041] - The noise from the image transmission chain;

[0042] - The viewing angle.

[0043] Some typical examples of information that can be obtained from a digital image: average brightness, average contrast, main color, average sharpness level (clear or blurred), color uniformity, the presence or absence of certain objects.

[0044] When, for example, changing the tires of a transport vehicle at a mining site, the method according to the present invention is carried out. The loading and unloading equipment moves towards the transport vehicle at the mining site with the camera activated. The operator of the loading and unloading equipment knows from the central monitoring station the position of the tire to be moved on the vehicle, which delimits the working area without precisely knowing the identifiers of the tire and the sensor.

[0045] The transport vehicle is detected by searching for and reading the identification number displayed on the bucket or the front of the vehicle. Another possibility is to use the visual features of a vehicle that is actually a dumper. Thus, vehicle identification includes using image processing software to identify visual features in the image generated by the camera.

[0046] The central database contains vehicle data, such as the number of axles, single or double components of each axle. According to the vehicle identifier, the central database can be queried to read vehicle-related data.

[0047] The identifier of the tire and its sensor is detected by activating the reading of the RFID tag of the tire and / or the sensor from the loading and unloading equipment. By cross-referencing the information read from the database with the information of the RFID reader, the tire to be replaced can be accurately identified.

[0048] The next step is to update the database using the identifiers of the replacement tire and its sensor and the identifier of the vehicle.

[0049] The number of transport vehicles depends on the size of the mining site, but generally, dozens of transport vehicles require one or two loading and unloading equipment (tire handlers).

[0050] The organization of the operation includes storage areas for new tires, worn tires, and replacement tires, as well as a working area for changing or swapping tires.

[0051] The loading and unloading equipment moves between the storage area and the working area where the transport vehicle is located.

[0052] According to the first variant, the method includes the following steps: The loading and unloading equipment activates the detection of the storage area for used tires through a video acquisition and processing system.

[0053] According to the second variant, the method includes the following steps: The loading and unloading equipment places the worn tire in the storage area for used tires.

[0054] According to the third variant, the method includes the following steps: The loading and unloading equipment activates the detection of the storage area for replacement tires by means of a video acquisition and processing system.

[0055] In one variant of the present invention, the video acquisition device includes a three-dimensional (3D) vision camera.

[0056] Cameras operating according to the time-of-flight principle are capable of measuring three-dimensional (3D) scenes in real time.

[0057] To this end, these cameras illuminate the scene and objects being measured by a flash (usually a laser), and calculate the time required for the flash to travel between the object and the camera. The time-of-flight of this flash is proportional to the distance between the camera and the object being measured. The measurement of this time-of-flight is performed independently for each pixel of the camera, thereby generating a complete 3D image of the object being measured.

[0058] As an alternative to time-of-flight 3D vision, according to different variants of the present invention, the video acquisition device includes a video system having two two-dimensional (2D) cameras.

[0059] The video acquisition device is used to identify the vehicle, its position relative to the loading and unloading equipment, and the position of the tire to be replaced on the axle.

[0060] Video acquisition is achieved using two cameras: one camera has better resolution and a reduced field of view, for analyzing details and performing precise distance measurements, and the other camera is a wide-angle camera, capable of keeping most of the large truck in the image while achieving the positioning of the loading and unloading equipment, even at very short distances. When there is a number written on the side of the dump truck, this camera can also be used to identify the number of the large truck, because this number is usually displayed at a very high position, or entirely on the front of the large truck.

[0061] It should also be noted that this camera is not intended to monitor the tire, but to identify the position related to the vehicle, or the position in the storage area, where the position of the tire on the tire handling machine may be very different from other cameras.

[0062] The tire of the device (D) preferably includes a system having a passive identification tag and a sensor attached to the inside of the tire, and the sensor includes a micro reader communicating with the tag.

[0063] RFID transponders usually have a relatively short reading distance. For civil engineering machinery tires with a diameter that can reach 4m, if the transponder is located, for example, at a higher position and far from the reader, the distance is usually not sufficient to ensure reading. According to the present invention, this limitation is overcome by using an active electronic module having a longer distance data transmission device itself.

[0064] The sensor and the passive tag system are advantageously equipped with an active electronic module for measuring and transmitting physical parameters of the tire, which includes:

[0065] i) at least one sensor (e.g., a temperature sensor, a pressure sensor, preferably a tachometer in the form of a coil, etc.);

[0066] ii) Power the sensor;

[0067] iii) A data transmission module that transmits the physical data received from the sensor to a remote receiver;

[0068] iv) A sensor that can selectively read tire tags.

[0069] This electronic module for measuring and transmitting physical tire parameter data can advantageously achieve:

[0070] - Reading of the tire identifier: periodically or on demand via an interrogation module, or in combination with a low - pressure or substantially zero - pressure threshold test indicating that the tire and the sensor may have become separated;

[0071] - Storing this identifier in local or remote memory;

[0072] - Transmitting this identifier via a substantially long - range transmission channel to a vehicle receiver, a mobile reader, or a reading terminal;

[0073] - In the case of a sensor capable of reading tire identifiers, associating the measured physical tire parameters with the appropriate tire in some way, for example by associating these parameters (km, pressure, temperature, etc.) with a repaired tire identifier that is associated with the tire on which the measurement is performed.

[0074] According to a variant of the invention, a GPS device is used to detect the storage area of the tire.

[0075] According to different variants, a GPS device and a local beacon are used to detect the position of the tire on the vehicle axle.

[0076] The invention also relates to loading and unloading equipment for tires of transport vehicles in mining sites. The vehicle has tires, which are characterized in that they are equipped with the device according to the invention.

[0077] According to a variant of the invention, the loading and unloading equipment (TH) for transport vehicle tires is characterized in that it includes a screen for monitoring and for interacting with the operator of the loading and unloading equipment (TH), for the steps of the method according to the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0078] The invention will be better understood by reading the following description, given by way of non - limiting example and with reference to Figures 1 to 5 given below, in which:

[0079] - Figure 1 - A to Figure 1 - E present an overview of the devices used in the invention;

[0080] -Figure 2 Shows a handling device with a video acquisition device;

[0081] - Figure 3 Shows a device for a transport vehicle according to the present invention;

[0082] - Figure 4 -A shows a transport vehicle, Figure 4 -B shows the associated visual signature for an image processing algorithm;

[0083] - Figure 5 -A, Figure 5 -B, Figure 5 -C shows the working area around a transport vehicle at a mining site. Detailed description of the invention

[0084] In Figure 1 -A to Figure 1 -E, the general reference numeral 10 represents a reserve of new, worn or replacement tires 11. The reference numeral 12 is a visual recognition identifier for the storage area. The reference numeral 20 relates to a transport vehicle at a mining site, and the reference numeral 21 refers to a tire equipped with a radio frequency identification (RFID) tag and a sensor. The reference numeral 22 represents a visual recognition identifier for the vehicle. The general reference numeral 40 represents an industrial vision system, which has a camera 41 and a computing unit 42. The camera 41 is equipped with an integrated lighting system, and the computing unit 42 has image processing software. The general reference numeral TH relates to the handling device in a top view, which includes a clamping fork 32 for clamping a tire 33 that remains vertical during movement. Finally, the reference numeral 50 refers to a monitoring system, which has a database 51 and a central station 52, and the central station 52 has a monitoring screen.

[0085] Figure 2 Shows a top view of a handling device with a camera 41 located at the front near the central axis of the tire 33 so that the tire can be photographed along the moving direction. The tire 33 is clamped between the clamping forks 32 of the handling device, and the clamping forks 32 communicate with the central base via an antenna 31.

[0086] Figure 3 Shows the transport vehicle represented by the general reference numeral 20, whose tire 33 is equipped with an RFID identifier 24 and a sensor 23. Due to the visual identifier 22, the vision system can detect the vehicle.

[0087] Figure 4 -A shows a transport vehicle having a visual signature 4-B or its reference image for identifying the vehicle in an image processing algorithm.

[0088] Figure 5 -A, Figure 5 -B, and Figure 5 -C each show, in a top view, a rigid dump truck, an articulated dump truck, and a loader as vehicles for a mining site according to the present invention. These figures also show work areas Z1, Z2, Z3, and Z4, which are places where activities such as mounting and dismounting tires are performed, for example, by means of handling equipment.

[0089] An exemplary embodiment of the present invention during the dismounting of a tire on a double rear axle will now be described.

[0090] The operator of the handling equipment is informed by the central station as to which work area is to be accessed to replace a defective tire. For example, this may concern the right front tire, but the operator of the handling equipment neither knows the identifier of the tire to be replaced nor the identifier of its sensor. In addition, for traceability, in addition to the identifier, the axle on which the tire is mounted and the position of the tire on that axle are information to be entered into the monitoring database.

[0091] The dismounting operation proceeds according to the following steps:

[0092] a. The handling equipment positions itself within the work area by advancing towards the transport vehicle, based on the information received from the central station;

[0093] b. The camera is activated to detect the axle and the position of the tire on that axle, so as to feed into the database;

[0094] c. The handling equipment is used to dismount the tire to be replaced;

[0095] d. The clamped tire is transported by the handling equipment from the work area to the storage area;

[0096] e. On the way to the storage area, the operator of the handling equipment activates the radio frequency (RFID) reading of the tire and the sensor tag. The tire must be far enough away from the vehicle on which other tires are mounted and must be far enough away from the storage area to obtain only the response of the identifier of the transported tire and the response of the associated sensor;

[0097] f. The camera of the handling equipment is activated to detect the storage area where the tire is placed;

[0098] g. The monitoring database is updated using the identifier of the tire, the sensor, and the position of the tire on the axle and / or the storage position of the tire.

[0099] These vehicles have a two-axle or four-axle configuration based on their intended use, with single or double seats on the middle and rear axles. Reference images are associated with each transport vehicle configuration. For example, Figure 4 -A, and Figure 4-B shows a transport vehicle and a related reference image respectively.

[0100] To update the database, it is necessary to identify the axle on which the tire to be replaced is mounted and its position on that axle. The axle and the position on the axle are detected by a three-dimensional (3D) camera.

[0101] After disassembly, the tire remains clamped between the clamping forks of the handling device and is in a vertical position, aligned parallel to the direction of movement. Due to the space defined by the diameter of the rim, the camera is located at the front of the handling device close to the axis of the tire to take pictures along the direction of movement. This diameter is usually in the range of 49 to 63 inches.

[0102] Axle detection is performed using an activated 3D camera when the handling device advances towards the transport vehicle. The camera transmits the image to a processing unit, which compares the image with the reference image to identify the relevant axle within the working area.

[0103] In the case of a double seat, it is necessary to determine the position of the tire on the axle. The tire occupies an inner position or an outer position on the axle. A video acquisition system with relevant image processing is used to determine this position.

[0104] The position on the axle is again determined by the movement of the handling device towards the vehicle, using an activated 3D camera. The image of the vehicle wheel hub is transmitted to the processing unit in real time. The processing unit calculates the distance between the camera and the wheel hub. If the distance between the camera and the wheel hub is less than the minimum distance between the camera and the tire sidewall, the position of the tire on the axle is on the inner side, otherwise it is on the outer side.

Claims

1. A method (P) for monitoring the tires of a vehicle (20) transporting excavations in a mining site using a tire handling device (TH), wherein the tires (33) are equipped with radio frequency identification tags (24) and physical parameter sensors (23); the method (P) also uses a database (B) containing the identifier of the vehicle (20), the identifier of the tire, the identifier of the sensor, and the position of the tire on the axle, and the method (P) includes the following steps: a. The handling device (TH) receives an instruction containing the position of the tire to be replaced on the transport vehicle; b. The handling device (TH) identifies the transport vehicle by means of a video acquisition and processing system, the vehicle being equipped with a visual identifier capable of being detected; c. The handling device (TH) activates the detection of the tire to be replaced on the vehicle by means of a radio frequency device; d. The handling device (TH) activates the detection of the axle and the position of the tire on the axle by means of a video acquisition and processing system. In the case of a double-seat, the position of the tire on the axle is determined, the tire occupying an internal position or an external position on the axle, and a video acquisition system with relevant image processing is used to determine this position; e. The handling device replaces the tire to be replaced with a replacement tire; f. The database (B) is updated with the identifier of the vehicle and the replacement tire and the position of the replacement tire on the axle.

2. The method (P) according to claim 1, including the following steps: The handling device (TH) activates the detection of the storage area for used tires by means of a video acquisition and processing system.

3. The method (P) according to claim 2, including the following steps: The handling device places the worn tire in the storage area for used tires.

4. The method (P) according to any one of claims 1 to 3, including the following steps: The handling device activates the detection of the storage area for replacement tires by means of a video acquisition and processing system.

5. A device (D) for performing the method according to claim 1, the device (D) including: A video acquisition and processing system equipped with at least one camera, the at least one camera optionally having suitable lighting for identifying the vehicle, the vehicle being provided with a visual identifier capable of being detected by the image acquisition and processing system; A reading device for reading the identification tags of the sensors and the tires; a calculation and image processing device for detecting the axle and the position of the tire on the vehicle axle; and a database associating the identifier of the tire, the identifier of the vehicle on which the tire is mounted, and the position on the axle.

6. The device (D) according to claim 5, wherein, The video acquisition and processing system includes a 3D camera.

7. The device (D) according to any one of claims 5 to 6, wherein, The video acquisition and processing system includes a video system with two 2D cameras.

8. The device (D) according to claim 5, wherein, The tire includes a system with a passive identification tag and a sensor attached to the inside of the tire, the sensor including a reader for communicating with the tag.

9. The device (D) according to claim 8, wherein, The sensor and the passive tag system are provided with an active electronic module for measuring and transmitting the physical parameters of the tire, which includes: i. At least one sensor, at least one sensor being one of a pressure sensor, a temperature sensor, and a tachometer; ii. A power supply for operating the sensor; iii. A data transmission module for transmitting the physical data received from the sensor to a remote receiver; iv. A sensor capable of selectively reading the tire tag.

10. The device (D) according to claim 5, wherein, The storage area of the tire is detected using a GPS device.

11. The device (D) according to claim 5, wherein, The position of the tire on the vehicle axle is detected using a GPS device and a local beacon.

12. A tire handling device (TH) for a transport vehicle in a mining site, characterized in that, It is equipped with the device according to any one of claims 5 to 11.

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