Method for monitoring a CAN network and the equipment forming such a network

Abstract

The present invention relates to a method for installing a counting and guidance system for users in a parking lot, comprising a plurality of interconnected devices. The method comprises the following steps: connection (E1) to the CAN communication network; taking (E2) a first voltage measurement; connection (E3) to the CAN communication network; taking (E4) a second voltage measurement; determining (E5) the actual electrical energy consumption; comparing (E6) the determined actual electrical energy consumption with a reference energy consumption; switching off (E7) the power supply; identifying (E8) the last connected device; interrupting (E9) the installation process; and iterating the preceding steps. Abstract figure: Figure 2

Description

Title of the invention: Method for monitoring a CAN network and the equipment forming such a network technical field

[0001] The present invention relates to the field of counting and guiding users in a parking lot.

[0002] More specifically, the invention relates to counting and guidance systems for users in a parking lot with a decentralized and autonomous architecture. PRIOR TECHNOLOGY

[0003] As is known, a conventional system for counting and guiding users in a parking lot requires the installation and connection of equipment including, in particular, vehicle presence detection equipment and display equipment, connected within a CAN communication network (“Controller Area Network”).

[0004] The installation and commissioning of a conventional system for counting and guiding users in a parking lot generally includes the following steps: • a preliminary study phase to establish a wiring plan defining the identifiers and locations of the equipment, and the connections between the equipment; • a factory configuration step for each piece of equipment using a unique identifier in accordance with the wiring plan; • an installation and connection stage for equipment in accordance with the wiring plan; • a step of entering the wiring plan into a computer system for managing and monitoring the parking lot.

[0005] If one of the devices connected to the communication network is not installed in the correct physical location, the information relayed to users is likely to be erroneous. Consequently, a drawback of the conventional system for counting and guiding users in a parking lot lies particularly in the lack of margin for error in the physical location of each device connected to the communication network during the installation and connection process.

[0006] Furthermore, the wiring diagram of such a conventional system is generally fixed. Consequently, if a problem arises requiring the replacement of defective equipment in the counting and guidance system instead For users in a parking lot, the replacement equipment must be identified with the same identifier as the defective equipment. Therefore, the replacement equipment must be pre-configured on a case-by-case basis at the factory, increasing the time between the occurrence of the problem and its resolution.

[0007] Any intervention, whether it takes place during the installation of a conventional counting and guidance system for users in a parking lot or during the replacement of defective equipment, requires the implementation of control operations to verify the conformity between the physical installation and the wiring plan. These control operations can be lengthy and tedious. Furthermore, they do not guarantee with absolute certainty that the physical installation conforms to the wiring plan.

[0008] Document FR3116367A1 describes a method for automatically mapping, configuring, and identifying equipment connected within a CAN communication network. However, errors occur in the selection of cables with a gauge lower than that recommended in the technical specifications.

[0009] During installation, some network cables may be of excessive length. Installation operators may sometimes exceed the initially planned length due to wiring errors. Furthermore, operators may use cables with a cross-section different from that initially specified in the wiring plan. It is very difficult to accurately measure the amount of cable used for the installation on-site once it has been completed. It is even more difficult to make subsequent modifications to the wiring once the parking guidance system is installed and the parking garage is operational.

[0010] Furthermore, the network cables used can themselves have defects. For example, the connectors on network cables, such as RJ45 cables manufactured on-site, may have defects: incorrect pairing, reversed wiring, open circuits, missing conductors in the connector during crimping, etc. Operators rarely test these cables, unlike standard commercially available Ethernet network cables which are systematically accepted. Cables are frequently damaged by excessive bending, friction on cable trays, accidental damage, etc., which creates permanent and intermittent short circuits.

[0011] The invention aims to remedy all or part of the aforementioned drawbacks of the prior art, by proposing an installation method preventing human installation errors and enabling the detection of material malfunctions of the components of a counting and guidance system, allowing a connection respecting a wiring plan of a plurality of detection equipment by network cables within a CAN communication network. PRESENTATION OF THE INVENTION

[0012] More specifically, the invention relates to a method for installing a counting and guidance system for users in a parking lot comprising a plurality of equipment intended to be connected to each other by a plurality of network cables within a CAN communication network according to a predetermined wiring plan, the method comprising the following steps: • the connection of the CAN communication network to a power supply for the counting and guidance system, • the performance of an initial voltage measurement of the electrical supply; • connection to the CAN communication network via a network cable of the plurality of cables of a piece of equipment of the plurality of equipment, said equipment having a unique identifier; • the performance of a second measurement of the power supply voltage and a measurement of the intensity of an electric current in the last network cable used for the last piece of equipment connected to the CAN communication network; • the determination of effective electrical energy consumption as being a sum of the electrical energy consumption of the last connected equipment with the electrical energy consumption of the last network cable used to connect said last equipment; • the comparison of the actual electrical energy consumption determined with a reference energy consumption; • the interruption of the power supply in the last network cable used for the last connected equipment in the event that a ratio between the determined actual electrical energy consumption and the reference energy consumption is less than a first threshold or greater than a second threshold, information on the power interruption being transmitted to an operator; • the identification of the last piece of equipment connected to the CAN communication network via the unique identifier of said last piece of equipment; • the interruption of the installation process in the event that the unique identifier of the last equipment connected to the network is different from an expected unique identifier from the system wiring plan, information about the interruption being transmitted to an operator; • iterating the previous steps to connect new equipment to the CAN communication network.

[0013] Thanks to this combination of features, the risk of an operator incorrectly assembling the metering and guidance system in place of users is significantly reduced. Furthermore, the operator can locate the source of the error and make a correction during installation, rather than after installation is complete. By comparing the actual energy consumption to a reference value, the operator can determine, for example, that the network cable used is longer than initially planned, particularly in a cabling plan, resulting in increased energy loss in the cable. The operator can also identify material defects, for example, in the cable itself, or abnormal contacts at the cable exit, for example, at connectors.The risk of assembly error by the operator is also reduced by the identification of new equipment connected to the CAN communication network.

[0014] Advantageously, the first threshold is equal to 0.95 and the second threshold is equal to 1.05. Moreover, the second threshold is greater than the first threshold.

[0015] Advantageously, after identifying the last piece of equipment connected to the CAN network, the method comprises the following steps: • measuring the intensity of the current from the power supply, upstream of the CAN communication network; • the determination of the intensity of a current associated with line losses as being a difference between the intensity of the current measured previously and a predetermined intensity of each piece of equipment connected to the CAN communication network; • the comparison between the intensity of the current associated with the determined line losses and a reference intensity as a function of a predetermined length of the CAN communication network.

[0016] In such a configuration, the operator can thus highlight the existence of non-compliant network cables, in particular having a cross-section smaller than a reference cross-section, for example the use of 26AWG or 28AWG gauge network cables instead of 24AWG network cables.

[0017] Advantageously, the reference current is obtained for a CAN communication network length of 500 m. Even more preferably, the reference current is obtained for a CAN communication network comprising 5th category network cables of 24AWG gauge.

[0018] Advantageously, the method includes a step of incrementing an identification error counter in the event of an interruption of the installation process.

[0019] Advantageously, for each step of the process, an implementation instruction is transmitted to an operator. In such a configuration, an operator unfamiliar with the process steps can obtain guidance for the correct execution of the current step. Preferably, the operator receives visual guidance, for example via a screen connected to the counting and guidance system.

[0020] Advantageously, each piece of equipment transmits a measurement of its internal operating temperature via the CAN network. In such a configuration, an operator has additional information to determine the correct installation of the equipment in the counting and guidance system.

[0021] According to another aspect of the invention, it relates to a counting and guidance system for parking spaces in a car park, comprising a plurality of devices intended to be connected to each other by a plurality of cables within a CAN communication network according to a predetermined wiring plan, configured for installation in a car park in accordance with the method described above. PRESENTATION OF FIGURES

[0022] The invention will be better understood upon reading the following description, given solely by way of example, and referring to the accompanying drawings given by way of non-limiting examples, in which identical references are given to similar objects and on which:

[0023] Fig. 1 is a schematic representation of a counting and guidance system for users in a parking lot;

[0024] Figure 2 is a flowchart describing steps in an installation process according to a first embodiment of the invention;

[0025] The [Fig.3] is a flowchart describing other steps of an installation process according to another embodiment of the invention.

[0026] It should be noted that the figures set out the invention in detail to enable implementation of the invention; although not limiting, said figures serve in particular to better define the invention where appropriate. DETAILED DESCRIPTION OF THE INVENTION

[0027] The invention relates in particular to a system 2 for counting and guiding users in a parking lot 1. The system 2 includes, in particular, once installed in the parking lot 1, a plurality of equipment 6. The equipment 6 may in particular include detectors configured to detect the presence of a user's vehicle in a parking lot 1 space. For example, as illustrated in [Fig. 1], the system 2 includes, opposite each parking lot 1 space, a detection equipment 6.

[0028] To enable vehicle detection via the equipment 6, the system 2 includes a power supply 10, configured to supply electrical power to each piece of equipment 6 in the system 2. Furthermore, the transmission of information acquired via a piece of equipment 6 to a remote processing unit 12 is carried out via a CAN communication network 4, which notably has characteristics conforming to ISO 11898-1 and features a self-contained and decentralized architecture. The power supply 10 is preferably mains-connected and receives an alternating voltage of 230V. The power supply 10 preferably transmits electrical power to the CAN communication network 4 at a direct voltage of 48V.

[0029] Here, the equipment 6 is connected to each other, to the power supply 10, and to the remote processing unit 12 via network cables 8. Each network cable 8 is preferably a standard Category 5, 24AWG computer cable. The network cable 8 has a dual function. On the one hand, the network cable 8 is configured to transmit electrical power from the power supply 10 of one piece of equipment 6 to another piece of equipment 6. On the other hand, the network cable 8 is configured to connect each piece of equipment 6 within the CAN communication network 4. The network cable 8 advantageously has eight conductors; the network cable 8 then preferably includes RJ45 type connectors. In this configuration, six of the eight conductors of said connector are dedicated to the transfer of electrical power from the power supply 10 of one piece of equipment 6 to another piece of equipment 6.Two of the eight conductors of said socket are then dedicated to the connection of equipment 6. This architecture is traditionally referred to as "CAN bus" by those in the trade.

[0030] The installation of the counting and guidance system 2 for users in a parking lot 1 is carried out according to a predetermined wiring plan. This predetermined wiring plan specifies, in particular, for each piece of equipment 6, a unique physical location and identifier within the CAN communication network 4.

[0031] According to another aspect of the invention, it relates to a method for installing a counting and guidance system 2 for users in a parking lot 1, as illustrated in [Fig. 2]. The installation method is carried out by one or more operators, equipped with the predetermined wiring diagram for the system 2. The following description focuses on describing each step of the method, the steps preferably being carried out in the order described, particularly in cases where the completion of a step is conditional upon the completion of a preceding step.

[0032] The method includes a step of connecting the CAN communication network 4 to the power supply 10 of the counting and guidance system 2. The El connection is made via a network cable 8, connected to the power supply 10.

[0033] The process then includes a step E2 of carrying out a first voltage measurement of the power supply 10, in particular of the voltage at the output of the power supply 10.

[0034] The method then includes a step of connecting E3 to the CAN communication network 4, via a network cable 8, of a piece of equipment 6.

[0035] The method then includes a step E4 of carrying out a second measurement of the voltage of the power supply 10, in particular of the voltage at the output of the power supply 10, and of a measurement of the intensity of an electric current in the last network cable 8 used for the last equipment 6 connected to the CAN communication network 4.

[0036] The method then includes a step E5 of determining an effective electrical energy consumption as being a sum of the electrical energy consumption of the last connected equipment 6 with the electrical energy consumption of the last network cable 8 used to connect said last equipment 6. Said electrical energy consumption of the equipment 6 and the electrical energy consumption of the last network cable 8 are each obtained by means of the electrical current measurement carried out in the previous step.

[0037] The method then includes a comparison step E6 of the actual electrical energy consumption determined with a reference energy consumption. The reference energy consumption is an ideal value, which corresponds to the expected energy consumption for electrical equipment 6 and a network cable 8 that would be connected according to the wiring plan and for a network cable 8 having a given length defined in the wiring plan, as described previously.

[0038] A ratio between the determined actual electrical energy consumption and the reference energy consumption is then calculated. To validate the correct installation of the last piece of equipment 6 and the last connected network cable 8, the calculated ratio must then fall between a first threshold and a second threshold, the second threshold being higher than the first threshold. The first threshold is preferably equal to 0.95. The second threshold is preferably equal to 1.05.

[0039] If the calculated ratio is less than the first threshold or greater than the second threshold, the method then includes a step E7 of cutting off the electrical power supply 10 in the last network cable 8 used for the last connected piece of equipment 6. Such a value of the calculated ratio indicates to the operator, for example, an error in the connection of the equipment 6, for example, due to an excessive length of network cable 8. Alternatively, such a value may indicate a hardware malfunction of the network cable 8, for example an abnormal contact at an RJ45 socket of said network cable 8. The operator can then directly and unambiguously locate the network cable 8 and / or the equipment 6 and the error can be corrected significantly more easily on a system 2 being installed than on a fully installed system 2.

[0040] Alternatively, in the case where the calculated ratio is between the first threshold and the second threshold, the method includes an identification step E8 of the last equipment 6 connected to the CAN communication network 4 via the unique identifier of said last equipment 6.

[0041] If the unique identifier of the last connected device 6 on the CAN communication network 4 differs from an expected unique identifier from the system 2 wiring diagram, the installation process includes an interrupt E9, and information about the interrupt is transmitted to an operator. This operator can then determine that the last connected device 6 is not at its assigned physical location by observing a difference between the identifier of said device 6 and the identifier expected by the CAN communication network 4. The process is interrupted as long as the identifiers differ.

[0042] Advantageously, the remote processing unit 12 connected to the CAN communication network 4 increments an identification error counter for each incorrect identification. In such a configuration, wiring errors of equipment 6 in an inappropriate location are monitored and error statistics can be generated.

[0043] Advantageously, the identification error counter is provided as input to an inference engine. The repository of known defects based on identified errors feeds a database on which artificial intelligence provides diagnostics for resolving the errors most commonly made by operators.

[0044] The operator(s) implementing the installation process then iterate through the previous steps to connect a new piece of equipment 6 to the CAN communication network 4. The process is complete once all the equipment 6 is connected, its actual power consumption complies with the specified thresholds, and the physical location of the equipment 6 and its unique identifiers conform to the predetermined wiring plan. Advantageously, an implementation instruction is transmitted to the operator, for example, via a visual instruction on a digital tablet.

[0045] Figure 3 illustrates additional steps of the installation process according to another embodiment. The steps illustrated in Figure 3 and described below are of preferences made after identification E8 of the last equipment 6 connected to the CAN 4 communication network.

[0046] The method advantageously includes a measurement step E10 of the current intensity from the power supply 10, upstream of the CAN communication network 4.

[0047] The method then includes a step El 1 for determining the intensity of a current associated with line losses. The intensity of the current associated with line losses is defined as the difference between the intensity of the current measured in the preliminary measurement step E10 and a predetermined intensity for each piece of equipment 6 connected to the CAN communication network 4.

[0048] The method then includes a comparison step E12 between the current intensity associated with the determined line losses and a reference current intensity, which is a function of a predetermined length of the CAN communication network 4. If the CAN communication network 4 has a given length greater than the length specified in the wiring plan, the current intensity associated with the line losses is then greater than the reference current intensity. By implementing these additional steps at each iteration of the method, i.e., during the installation of each new piece of equipment 6, it is possible to determine that the last connected network cable 8 has a length greater than that expected and predetermined in the wiring plan. The operator can thus reduce the length of the network cable 8 during installation.

[0049] When the additional steps are carried out at the end of the installation process, i.e. when all the equipment 6 is connected, the reference intensity is obtained for a length of the CAN communication network 4 of 500m.

[0050] It should also be noted that the invention is not limited to the embodiments described above. It will indeed be apparent to a person skilled in the art that various modifications can be made to the embodiment described above, in light of the information just disclosed to them.

[0051] In the detailed presentation of the invention given above, the terms used shall not be interpreted as limiting the invention to the embodiment set forth in this description, but shall be interpreted to include all equivalents which can be foreseen by a person skilled in the art by applying their general knowledge to the implementation of the teaching which has just been disclosed to them.

Claims

1. Demands Method for installing a counting and guidance system for users in a parking lot (1) comprising a plurality of equipment (6) intended to be connected to each other by a plurality of network cables (8) within a CAN communication network (4) according to a predetermined cabling plan, the method comprising the following steps: • the connection (El) of the CAN communication network (4) to a power supply (10) of the counting and guidance system, • the realization (E2) of a first measurement of the voltage of the electrical supply (10); • the connection (E3) to the CAN communication network (4) via a network cable (8) of the plurality of cables of a piece of equipment (6) of the plurality of equipment (6), said equipment (6) having a unique identifier; • the performance (E4) of a second measurement of the voltage of the power supply (10) and of a measurement of the intensity of an electric current in the last network cable (8) used for the last piece of equipment (6) connected to the CAN communication network (4); • the determination (E5) of an effective electrical energy consumption as being a sum of the electrical energy consumption of the last equipment (6) connected with the electrical energy consumption of the last network cable (8) used to connect said last equipment (6); • the comparison (E6) of the actual electrical energy consumption determined with a reference energy consumption; • the interruption (E7) of the power supply (10) in the last network cable (8) used for the last connected piece of equipment (6) in the event that a ratio between the determined actual electrical energy consumption and the reference energy consumption is less than a first threshold or greater than a second threshold,

2.

3.

4.

5. information about the power outage (10) being transmitted to an operator; • the identification (E8) of the last equipment (6) connected to the CAN communication network (4) via the unique identifier of said last equipment (6); • the interruption (E9) of the installation process in the event that the unique identifier of the last piece of equipment (6) connected to the network is different from an expected unique identifier from the system wiring plan, information about the interruption being transmitted to an operator; • iteration of the previous steps for connecting new equipment (6) to the CAN communication network (4). Installation method according to claim 1, wherein the first threshold is equal to 0.95 and the second threshold is equal to 1.

05. Installation method according to claim 1 or 2, comprising, after identification of the last piece of equipment (6) connected to the CAN network (4), the following steps: • the measurement (E10) of the intensity of the current from the power supply (10), upstream of the CAN communication network (4); • the determination (El 1) of the intensity of a current associated with line losses as being a difference between the intensity of the current measured previously and a predetermined intensity of each piece of equipment (6) connected to the CAN communication network (4); • the comparison (E12) between the intensity of the current associated with the determined line losses and a reference intensity as a function of a predetermined length of the CAN communication network (4). Installation method according to any one of the preceding claims, wherein the reference intensity is obtained for a length of the CAN communication network (4) of 500 m. Installation method according to any one of the preceding claims, comprising incrementing an identification error counter in the event of an interruption of the installation method.

6. Installation method according to claim 5, wherein the identification error counter is provided as input to an inference engine.

7. An installation method according to any one of the preceding claims, wherein for each step, an implementation instruction is transmitted to an operator.

8. Installation method according to any one of the preceding claims wherein each piece of equipment (6) transmits a measurement of its internal operating temperature via the CAN network (4).

9. A counting and guidance system for users in a parking lot (1) comprising a plurality of equipment (6) intended to be connected to each other by a plurality of cables (8) within a CAN communication network (4) according to a predetermined wiring plan, configured to be installed in a parking lot (1) in accordance with the method according to any one of the preceding claims.