Diagnostic method and system for the function of an automatic or semi-automatic access device to a transport vehicle

Description

[0001] The present invention relates to a method for diagnosing the operation of an automatic or semi-automatic device for accessing a transport vehicle, a system for diagnosing the operation of such an automatic or semi-automatic device and a transport vehicle equipped with such a system.

[0002] The invention relates to the field of maintenance of transport vehicles, in particular railway vehicles.

[0003] The diagnosis of the functioning of a system, in English "health status assessment", includes the detection of degradations likely to lead to failures and the characterization of each degradation: the identification of the component(s) at the origin of the degradation observed, the identification of the type of degradation and the estimation of the severity of the degradation.

[0004] The automatic or semi-automatic vehicle access devices concerned include in particular doors or gap fillers, also known as anti-fall devices, of the type comprising at least one opening adapted to be actuated by a kinematic chain comprising at least one electrically powered motor and possibly having an associated angular position and / or rotation speed encoder.

[0005] Reducing maintenance costs, in-service breakdowns, and downtime are three major areas for improvement in the railway industry. Automatic or semi-automatic access devices, such as passenger access doors, represent a significant part of the improvement prospects because there are many of them on a vehicle such as a train, which further impacts maintenance costs, vehicle availability, and reliability. This is why it is essential to ensure their proper functioning by monitoring their health over time. In particular, the objective is twofold: to detect degradations likely to lead to failures and to diagnose (locate, identify, and estimate the severity) these degradations, sufficiently in advance of a breakdown and without major modifications to existing products.For example, the number of additional sensors or acquisition cards must be limited.

[0006] Furthermore, it is important to ensure proper operation within pre-established safety margins, i.e. the diagnostic system must not impact the security of access devices.

[0007] Finally, in the event of a predicted failure, it is useful to identify which components, parts of the drivetrain are exhibiting degraded behavior, mechanical malfunctions, as well as shortages of consumables such as grease.

[0008] Document WO 01 / 34446 A1 describes a predictive maintenance system for an automatic door of a railway vehicle.

[0009] Document EP 3 038 048 A1 describes a system for automatically determining the degradation of a vehicle component for the purpose of targeted predictive maintenance.

[0010] The invention aims to provide detection of damage and diagnosis of the operation of an automatic or semi-automatic device for access to a transport vehicle in this context.

[0011] To this end, the invention relates to a method for diagnosing the operation of an automatic or semi-automatic device for accessing a transport vehicle according to claim 1.

[0012] Advantageously, the method of the invention makes it possible to characterize each actuation cycle of the kinematic chain into several functional segments, and consequently to characterize its operation in detail.

[0013] The method according to the invention may have one or more of the characteristics of dependent claims 2 to 10.

[0014] According to another aspect, the invention relates to a system for diagnosing the operation of an automatic or semi-automatic device for accessing a transport vehicle according to claim 11.

[0015] The invention also relates to a transport vehicle comprising a plurality of automatic or semi-automatic access devices, each automatic or semi-automatic access device comprising at least one opening adapted to be actuated by a kinematic chain comprising at least one electrically powered motor and having an associated angular position and / or rotation speed encoder, and being equipped with a system for diagnosing the operation of the automatic or semi-automatic access device as briefly described above.

[0016] Other characteristics and advantages of the invention will emerge from the description given below, for information purposes only and in no way limiting, with reference to the appended figures, among which: there figure 1 schematically illustrates a detail of a railway vehicle equipped with an automatic or semi-automatic door operating diagnostic system according to one embodiment; the figure 2 is a synopsis of the main steps of a method for diagnosing the operation of an automatic or semi-automatic door according to one embodiment; figure 3 schematically illustrates the division of an actuation cycle of a kinematic chain of an automatic or semi-automatic door into a plurality of functional segments.

[0017] The invention will be described below in its application to the diagnosis of the operation of automatic or semi-automatic doors of a rail transport vehicle.

[0018] It is understood that the invention is not limited to this application, and applies in a similar manner for the diagnosis of operation of another automatic or semi-automatic device for access to a transport vehicle, for example a gap filler, which aims to fill a horizontal gap between the vehicle and the loading / unloading platform (for example a train or metro platform).

[0019] There figure 1 schematically illustrates a portion of a railway vehicle 2, relating to an automatic door 4. Alternatively, it is a semi-automatic door, for example the opening of which is actuated by a manual action (e.g. pressing a push button, actuation of an emergency opening module or actuation of a maintenance opening module).

[0020] In the following, the terminology "door" will include both fully automatic and semi-automatic doors.

[0021] It is understood that a railway vehicle generally has several attached cars, and at least as many doors 4 as cars.

[0022] Rail vehicle 2 is, for example, a train, tram or metro, more generally called rolling stock.

[0023] In one embodiment, the doors are automatic or semi-automatic passenger access doors. However, the invention is not limited to this embodiment.

[0024] The door 4 comprises a frame 6, that is to say a frame, which is a structure fixed or integrated into the body of the railway vehicle and an opening 8.

[0025] In one embodiment, the opening 8 is formed by two leaves adapted to slide in opposite directions to achieve a central closure. Of course, other embodiments are conceivable, for example a single leaf adapted to slide to achieve the opening and closing positions.

[0026] The opening 8 is actuated by a kinematic chain 10 comprising in particular a motor 12 whose rotation (illustrated by an arrow on the figure 1 ) causes the movement of the opening 8 and the opening (respectively the closing) of the door 4.

[0027] The motor 12 comprises a drive unit 14, electrically powered by a source of electricity not shown. For example, when the vehicle 2 is an electric vehicle, the drive unit is an auxiliary load powered by the same source as the main motor (not shown) of the electric vehicle. This source is for example an electrified track.

[0028] The electric current intensity I and / or the electric current voltage V supplying the drive unit 14 are controlled by a control unit 20 described below.

[0029] The motor 12 also comprises or is associated with an angular position and / or speed encoder 16, which is a sensor of known type which makes it possible to acquire information on the angular position or rotational speed of the motor.

[0030] This information is transmitted in the form of an encoder signal SC to the control unit 20.

[0031] The control unit 20 is a unit comprising at least one processor 22, adapted to implement calculations by executing program code instructions. It is for example a programmable electronic card. It also comprises input / output units 24, 26.

[0032] It also has an internal 28 clock generator.

[0033] The kinematic chain 10 also comprises at least one switch 18, indicating for example a closed door position and / or a locked door position, and the control unit 20 receives information 30 relating to the open / closed state of each switch 18.

[0034] In addition, optionally, the control unit 20 receives other information 32 relating to elements not shown of the door 4, such as for example pressing a push button, activation of an emergency opening or locking module.

[0035] Optionally, the control unit 20 receives information 34 relating to the vehicle 2, for example centralized opening / closing orders, train speed information or opening authorization.

[0036] Optionally, the control unit 20 receives context information 36, provided by an external system 35. For example, the context information consists of any information making it possible to indicate the state of the train and its environment when the diagnostic system is activated, for example meteorological data, such as for example the outside temperature, location data, internal data of the train, coming for example from the global control system of the railway vehicle 2. The context information 36 is stored. Their use in one embodiment will be described below.

[0037] In all embodiments, the control unit 20 is adapted to receive a control signal for opening the door 4, as well as a control signal for closing the door 4. Following such control signals for opening or closing the door, the control unit 20 is adapted to control the motor 12.

[0038] An actuation cycle of the kinematic chain 10 is then carried out between a first position among the opening and closing positions and a second position, different from the first position, among the closing and opening positions of said door. Such an actuation cycle is characterized by a duration, and an electrical energy for actuation of the kinematic chain, consumed during the duration of this cycle.

[0039] In addition, various elements of the kinematic chain 10, for example the switches 18, change state during the duration of such a cycle.

[0040] A system 40 for diagnosing the operation of the door 4 comprises a calculation unit 42 comprising at least one processor, adapted to execute code instructions implementing an operation diagnosis method as described in detail below.

[0041] In one embodiment, the operating diagnostic system 40 is implemented in the control unit 20.

[0042] In one variant, it is implemented by an electronic calculator separate from the control unit 20, which can be on board the vehicle or remote.

[0043] The operating diagnostic system 40 also comprises a storage unit 44, adapted to store data. The unit 44 stores in particular reference values of descriptors 46 as explained in more detail below.

[0044] Several implementation variants are envisaged: according to a first variant, the calculation unit 42 and the storage unit 44 are on board the rolling stock; according to a second variant, the calculation unit 42 and the storage unit 44 are unloaded, for example in a ground processing center and communicate with the control unit 20, for example by radio communication; according to a third variant, the calculation unit 42 and the storage unit 44 are distributed, comprising an on-board part, and a ground part. Examples of processing carried out on-board or on the ground will be given in the remainder of the description.

[0045] The operating diagnostic system 40 receives as input information relating to the powertrain 10, as well as information 32, 34 relating to the vehicle 2, and external commands.

[0046] This information includes at least one characteristic measurement of the electrical energy consumed by the motor 12, for example a current or voltage measurement, and information provided by the encoder 16.

[0047] At output, the operating diagnostic system 40 provides a diagnosis 48, comprising, in the event of detection of degradation(s), an operating report and a characterization of the detected degradations.

[0048] The diagnosis is, for example, displayed on a screen (not shown) for possible action by a maintenance operator, or transmitted to a supervision system (not shown) which takes action accordingly.

[0049] Where the system includes a display screen, this screen is preferably remote, for example located in a ground processing centre.

[0050] Alternatively or in addition, diagnosis 48 triggers an alarm, for example visual or audible, to warn a maintenance operator of the need to intervene to avoid a breakdown in service.

[0051] The main steps of an embodiment of the method for diagnosing the operation of an automatic or semi-automatic device for accessing a transport vehicle, implemented by the diagnostic system 40 are illustrated in figure 2 The method is applied to an automatic or semi-automatic door in the embodiment described in detail.

[0052] During a first acquisition step 52, operating information from the kinematic chain of the automatic or semi-automatic door in question is acquired by various means, for example by sensors or by parallel acquisitions of existing signals.

[0053] The acquisition of information relating to the operation of the powertrain is carried out on board the rolling stock (on-board mode).

[0054] In one embodiment, when the system 40 and the storage unit 44 are on board, the acquired operating information is stored and all of the processing steps described below are performed on board.

[0055] Alternatively, the acquired operating information is temporarily stored on board in an on-board storage unit and then transmitted, for example at regular time intervals, for storage in a remote storage unit and processing by a remote system 40, for example in a ground processing center.

[0056] Steps 54 to 60 described in detail below are in this case carried out by the system 40 in a ground processing center, from the operating information received by a means of communication.

[0057] Acquisition 52 involves acquiring several types of information.

[0058] On the one hand, we acquire information representative of the quantity of electrical energy consumed during a cycle, in particular the evolution of the current and voltage during a cycle.

[0059] Thus, at least one signal representative of the quantity of electrical energy consumed during the cycle is obtained, for example a current signal and / or a voltage signal consumed during the cycle.

[0060] Furthermore, the angular position and / or rotation speed encoder signal SC is also obtained during this acquisition step 52. This signal provides information on changes in the movement, for example accelerations or decelerations, or changes in engine speed. In addition, the angular position and / or rotation speed encoder signal SC can be used to calculate positions of the door leaf during the cycle.

[0061] In addition, optionally, binary information relating to opening and / or closing and / or locking positions of switches 18 is also received in the acquisition step 52.

[0062] The acquisition step 52 is followed by a step 54 of dividing the cycle into a plurality of functional segments, based on the information acquired in the acquisition step 52.

[0063] Indeed, an actuation cycle of the kinematic chain between a first position, for example the closing position of the door and a second position, for example the opening position, begins at a first instant T init of reception of an opening control signal or of opening of a given switch of the kinematic chain or by the detection of a movement of the motor or of the encoder, and ends at a second instant T final, for example given by the reception of information of blocking of the door or by the detection of an end of movement of the motor.

[0064] The division 54 consists of dividing the cycle between [T init , T final ] into a plurality of functional segments “Segment 1”, “Segment 2”,...., “Segment N” as schematically illustrated in figure 3 . Each segment "Segment n" is defined by an initial time T n-1 and a final time T n . The functional segments have variable durations, each functional segment corresponding to an operating phase of the door actuation cycle. The segments correspond, for example, to successive phases of acceleration of the door, movement of the door at a predetermined globally constant speed and deceleration of the door.

[0065] In one embodiment, the slicing is performed using information extracted from the position / speed encoder SC signal, for example based on changes in engine speed or specific positions.

[0066] Alternatively, the slicing is performed using received binary information indicating various gate positions, combined with information extracted from the position / speed encoder signal SC, e.g., based on changes in engine speed or specific positions.

[0067] Alternatively or in addition, signals representing the quantity of electrical energy consumed during the cycle are also used for this division, for example using pattern recognition principles.

[0068] For example, the detection of an initial ascending or descending ramp on the motor current can be used to detect the door starting to open or close, while a current phase stabilized for a given time can be used to indicate the end of an opening or closing cycle.

[0069] For example, a current peak can determine its acceleration / deceleration, for example when approaching a mechanical opening stop or when approaching a locking phase.

[0070] One can also optionally use time variables (fixed time from a point) to define a new segment.

[0071] Step 54 of dividing the cycle into functional segments is followed by a step 56 of calculating values of one or more descriptors per functional segment.

[0072] The descriptors are previously defined and selected.

[0073] For example, for each segment, one or more of the following descriptors are chosen: one or more values relating to the current and / or voltage of the electrical energy consumed during the time interval associated with the segment, such as for example the average, the variance, the integral of the current and / or the voltage; one or more values relating to the operation of the motor, for example the average speed or the average acceleration / deceleration during the time interval associated with the segment; the time duration d=T n -T n-1 associated with the functional segment Segment n; the positions of the gate associated with the instants T n-1 of the start of the segment and T n of the end of the segment, obtained using the encoder information, can be optionally used.

[0074] On the figure 3 , as a schematic example, the descriptor values relating to the functional segment “Segment 1” are noted V 1,1 ...V 1,K .

[0075] The calculated descriptor values are representative of the electrical energy consumed by the drive train during each functional segment of the actuation cycle and / or the duration of each functional segment and / or the door positions.

[0076] Step 56 of calculating descriptors per segment is followed by a step 58 of calculating one or more health indicators of the door, including the two types of health indicators described below.

[0077] There are two types of health indicators: an individual health indicator is associated with a descriptor and is relative to a particular aspect of the operating state. For example, an individual health indicator relating to a given descriptor and a given segment is equal to a distance between the descriptor value calculated for the segment and a reference value of said descriptor; a global health indicator is calculated from the values of the descriptors for all segments, and quantifies the overall health of the system. Its value is strictly positive. The closer its value is to zero, the healthier the system (here, the automatic or semi-automatic door considered) is. The higher its value, the more degraded the system is.

[0078] In one embodiment, a global health indicator is calculated by forming a global vector comprising at least a portion of the values of the descriptors, followed by calculating a distance between the global vector and a corresponding reference vector, in which each descriptor takes a previously stored reference value, for example a value in a so-called healthy state.

[0079] For example, the calculated distance is a statistical distance, for example the Mahalanobis distance.

[0080] Alternatively, the calculated distance is a Euclidean distance.

[0081] Step 58 is followed by a step 60 of establishing an operating diagnosis.

[0082] This step includes in particular the detection of degradation, and in the case of degradation detection, the characterization of the degradation, in particular the identification of the type of degradation.

[0083] In addition, the characterization of the degradation comprises, in one embodiment, the localization of the degradation, for example the determination of the element(s) of the kinematic chain having degraded operation, and the estimation of the severity of the degradation.

[0084] In one embodiment, for the detection of degradation, the overall health indicator, calculated in step 58, is compared to predetermined good operating thresholds. These good operating thresholds are determined by a statistical approach from the requirements in terms of false alarm rate and good detection rate. A degradation is detected when the value of the health indicator exceeds a predetermined good operating threshold.

[0085] An operating report is for example established periodically (step 62) and, in the event of detection of significant degradation, an alarm is for example issued in step 62.

[0086] Significant degradation is, for example, detected degradation whose estimated severity exceeds a predetermined severity threshold.

[0087] Advantageously, the method makes it possible to detect degradation before a failure occurs.

[0088] Furthermore, thanks to the plurality of functional segments and the plurality of health indicators used, it is also possible to identify the type of degradation and to identify the part of the degraded kinematic chain, or the adjustment not respected or the degraded / absent consumable.

[0089] In one embodiment, to identify the type of degradation, a signature vector is established, comprising at least a portion of the individual health indicators calculated in step 58. The portion of the health indicators to be taken into consideration for a given type of degradation is predetermined.

[0090] A similarity measure between the signature vector and each of the reference signature vectors is calculated. Said reference signature vectors consist of the individual health indicators calculated in step 58 for each stored degradation, for example during a test phase or upon observation of degradation, as explained below. The identification and localization of the degradation then consists of determining which of said reference signature vectors has the greatest similarity with the calculated signature vector.

[0091] For example, the similarity measure performed is a cosine similarity measure.

[0092] In addition, it is also possible to estimate the severity of the degradation, defined as the level of degradation reached between the healthy state and the maximum admissible degradation state. In one embodiment, the severity of the degradation is defined as a number commonly between the value zero and the value 1. The closer the value of said severity is to zero, the lower or even non-existent the degradation. The higher its value, the more severe the degradation.

[0093] For example, severity is calculated as the norm of the projection of the calculated signature vector onto the reference signature vector for the identified degradation.

[0094] Advantageously, the method then allows the identification, location and determination of the severity of one or more damages to the door and allows maintenance to be carried out more precisely.

[0095] The process allows, by monitoring the history of stored severity values, to determine the probability of failure for a given horizon.

[0096] Advantageously, maintenance is then carried out on time and helps prevent door failure.

[0097] The method of the invention has been described above for establishing a diagnosis of the operation of a door during its use.

[0098] The process can also be used in an upstream test phase, in particular on a dedicated test bench, before installation, in particular for the calculation of reference characteristic values in nominal operation or in degraded operation.

[0099] Furthermore, if degradation is observed during a commercial service or during a maintenance operation, after identifying the type of degradation and the degraded elements concerned and after estimating the severity of the degradation, it is possible to memorize the corresponding characteristic values in order to facilitate the subsequent identification of similar degradation.

[0100] Optionally, the system also uses the context information 36, which is for example stored in the storage unit 44.

[0101] Context can affect measurement, creating disturbances. The sensitivity of indicators to context can optionally be tested on a dedicated test bench.

[0102] We subsequently call context the vector consisting of all the values of the context information in a described situation.

[0103] In one embodiment, the values of the calculated descriptors are adjusted relative to the context, for example by a regression method.

[0104] In another embodiment, an instance of the diagnostic system is executed for each context class. A said context class is defined as a predefined set of context values. For example, the diagnosis of a door can be made from measurements taken at a regular interval at a defined location during the journey of the railway vehicle.

[0105] Advantageously, the influence of the context is reduced and the number of false alarms, wrongly indicating a degradation alarm, is thus reduced.

Claims

1. Method for diagnosing the operation of an automatic or semi-automatic device for accessing a transport vehicle comprising at least one opening part adapted to be actuated by a kinematic chain including at least one motor powered electrically and having an associated angular position and / or rotational speed encoder and, preferably at least one switch, the access device being movable between an opening position and a closing position, characterised in that it includes steps, implemented by a processor, for at least one cycle of actuating the kinematic chain between a first position among the opening and closing positions and a second position, different from the first position, among the closing and opening positions, consisting in: - during said cycle, acquiring (52) information relating to the kinematic chain comprising at least one piece of information representative of the electrical energy consumed by the motor, and / or position and / or speed information provided by said encoder and / or binary information indicating switch positions of the actuation kinematic chain, - dividing (54) said cycle into a plurality of functional segments according to said acquired information, - calculating (56) at least one descriptor value per functional segment, each functional segment having an associated time interval, and the descriptors being representative of the electrical energy consumed during said time interval and / or of a duration of the functional segment, - calculating (58) one or more individual health indicators per functional segment, - establishing (60) an operating diagnosis comprising a degradation detection according to at least some of said calculated descriptor values, and, in the event of degradation being detected, the method further includes: - a calculation of at least one signature vector including at least some of the individual health indicators, - estimating a measure of similarity between said signature vector and at least one reference signature vector representative of a type of degradation, and - an identification of a type of degradation according to the estimation of a measurement of similarity.

2. Method according to claim 1, wherein the division (54) into functional segments further uses motor acceleration / deceleration information obtained from information provided by said encoder.

3. Method according to claim 1 or 2, including determining information on acceleration / deceleration of the motor from the position and / or speed information provided by said encoder, and wherein said descriptor values comprise values representative of the speed or the average acceleration / deceleration of the motor during the time interval associated with each segment.

4. Method according to one of claims 1 to 3, including, before establishing a diagnosis, a calculation of a global health indicator according to a distance between a vector comprising all of the calculated descriptor values and a vector of reference values of corresponding descriptors previously stored.

5. Method according to claim 4, wherein said distance is a statistical distance or a Euclidian distance.

6. Method according to one of claims 4 or 5, wherein the establishment of an operating diagnosis includes a comparison of the calculated distance to a predetermined good operating threshold.

7. Method according to any one of claims 1 to 6, wherein the similarity measurement is a cosine similarity measurement.

8. Method according to any one of claims 1 to 7, further including an estimation of a detected degradation severity value, according to the signature vector and the reference signature vector associated with the identified type of degradation.

9. Method according to claim 8, wherein an alarm is raised if a detected degradation severity value exceeds a predetermined severity threshold.

10. Method according to any one of the preceding claims, including, prior to the division into functional segments, an acquisition of context information, and wherein the calculation of at least one descriptor value per functional segment is performed according to at least one item of context information.

11. System for diagnosing the operation of an automatic or semi-automatic device for accessing a transport vehicle comprising at least one opening part adapted to be actuated by a kinematic chain including at least one motor powered electrically and having an associated angular position and / or rotational speed encoder and preferably at least one switch, the access device being movable between an opening position and a closing position, characterised in that it includes a computing unit including at least one processor, adapted to implement, for at least one cycle of actuating the kinematic chain between a first position among the opening and closing positions and a second position, different from the first position, among the closing and opening positions, modules adapted to: - during said cycle, acquire information relating to the kinematic chain comprising at least one piece of information representative of the electrical energy consumed by the motor, and / or position and / or speed information provided by said encoder and / or binary information indicating switch positions of the actuation kinematic chain, - dividing said cycle into a plurality of functional segments according to said acquired information, - calculating at least one descriptor value per functional segment, each functional segment having an associated time interval, and the descriptors being representative of the electrical energy consumed during said time interval and / or of a duration of the functional segment, - calculate one or more individual health indicators per functional segment, - establish an operating diagnosis comprising a degradation detection according to at least some of said calculated descriptor values, the computing unit being adapted, in the event of degradation detection, to: - calculate at least one signature vector including at least some of the individual health indicators, - estimate a measurement of similarity between said signature vector and at least one reference signature vector representative of a type of degradation, and - identify a type of degradation according to the estimation of a measurement of similarity.

12. Transport vehicle including a plurality of automatic or semi-automatic access devices, each automatic or semi-automatic access device comprising at least one opening element suitable for being actuated by a kinematic chain including at least one electrically powered motor and having an associated angular position and / or rotational speed encoder, and being equipped with a system for diagnosing operation of an automatic or semi-automatic access device according to claim 11.