CONTROL OF THE PROVISION OF A QUANTITY OF A PHYSICAL QUANTITY BY A SERVER IN A CLIENT-SERVER ARCHITECTURE SYSTEM

Abstract

A control method is implemented in a system comprising a client-server architecture in which at least one server transmits initial minimum and maximum values ​​of a quantity of a physical quantity that it can provide, and at least one client generates and transmits to the server a setpoint between these initial minimum and maximum values ​​so that it provides a quantity of the physical quantity equal to this setpoint. This method includes a step (10-60) in which, if the server receives the setpoint at time t, it determines whether this setpoint is between initial minimum and maximum values ​​transmitted at time t - dt, where dt is a representative round-trip transmission time between the server and client, and if so, the server is authorized to provide a quantity of the physical quantity equal to this setpoint. Figure 3

Description

Title of the invention: CONTROL OF THE SUPPLY OF A QUANTITY OF A PHYSICAL QUANTITY BY A SERVER IN A CLIENT-SERVER ARCHITECTURE SYSTEM Technical field of the invention

[0001] The invention relates to systems comprising a client-server type architecture, and more specifically to the control of the supply of a quantity of a physical quantity by a server of such an architecture. State of the art

[0002] Some systems, such as certain vehicles (possibly of the automobile type), include a client-server architecture in which:

[0003] - at least one server is suitable for transmitting, via a communication network internal (possibly multiplexed), of the first minimum and maximum values ​​of a quantity of a physical quantity that it can provide, and

[0004] - at least one client is capable of generating and transmitting to the server, via the network of internal communication, a setpoint between these first minimum and maximum values ​​so that it provides a quantity of physical quantity equal to this setpoint.

[0005] By way of example, in a vehicle system, a server may be an assembly comprising a powertrain (or PWM) and a computer for monitoring this PWM, and a client may be a computer responsible for controlling the vehicle's movements (possibly for a speed and distance control function between vehicles). In this case, the physical quantity provided by the PWM is torque (in Nm).

[0006] In the client-server architecture described above, when the server receives a command from a client at time t, it is currently determined whether this command is between the first minimum and maximum values ​​currently held in the server at that time t. If so, the server is authorized to provide a quantity of the physical quantity equal to this command. If not, it is determined whether the transmitted command is between a second maximum value, equal to the sum of the first minimum value held at time t and a first margin, and a second minimum value, equal to the sum of the first maximum value held at time t and a second margin.Note that in a variant of the implementation it is also possible to determine immediately, i.e. without making the first determination, whether the transmitted setpoint is between a second maximum value, equal to the sum of the first minimum value in progress at time t and . of a first margin, and a second minimum value, equal to the sum of the first maximum value in progress at time t and a second margin.

[0007] This method of controlling the supply of the quantity of physical quantity has at least one drawback. Indeed, it does not take into account the round-trip transmission time between the server and client via the internal communication network, and therefore it frequently happens that the setpoint received at time t is not between the first minimum and maximum values ​​currently present in the server at that time t. This results from the fact that the first minimum and maximum values ​​vary over time, and sometimes very rapidly (and in particular more rapidly than the aforementioned round-trip transmission time).

[0008] Currently, to limit the consequences of the aforementioned drawback, the first and second margins are increased to compensate for the time lag related to the round-trip transmission time in order to avoid false detections. However, this is not entirely satisfactory because it prevents the first and second margins from actually corresponding to what is intended to be allowed.

[0009] The invention therefore aims in particular to improve the situation. Presentation of the invention

[0010] In particular, it proposes for this purpose a control method intended to be implemented in a system comprising a client-server architecture in which:

[0011] - at least one server is suitable for transmitting initial minimum values ​​and maximum amount of a physical quantity that it can provide, and

[0012] - at least one client is capable of generating and transmitting an instruction to the server between these first minimum and maximum values ​​so that it provides a quantity of physical quantity equal to this setpoint.

[0013] This control method is characterized by the fact that it includes a step in which, in the event of receiving the instruction by the server at a time t, it is determined whether this instruction is between the first minimum and maximum values ​​transmitted at a time t - dt, where dt is a duration representing a round-trip transmission time between the server and client, and if so, the server is authorized to provide a quantity of physical quantity equal to this instruction.

[0014] This consideration of the round-trip transmission time now makes it possible to compare instructions and first values ​​that correspond temporally, and therefore to use margins that effectively correspond to what we want to allow.

[0015] The control method according to the invention may include other features which may be taken separately or in combination, and in particular:

[0016] - in a first embodiment, in its step, a duration dt can be used predefined, equal to a predetermined round-trip transmission time between the server and client;

[0017] - in a second embodiment, in its step, a duration dt can be used which is equal to an absolute value of a difference between a first instant of transmission of first minimum and maximum values ​​and a second instant of reception of a setpoint generated consecutively to the reception of these first minimum and maximum values;

[0018] - in its step, a first minimum value transmitted at time t can be used - dt and integrating a first chosen margin, and a first maximum value transmitted at time t - dt and integrating a second chosen margin. Alternatively, we can determine if the transmitted setpoint is between a second minimum value, equal to a sum of the first minimum value transmitted at time t - dt and a first chosen margin, and a second maximum value, equal to a sum of the first maximum value transmitted at time t - dt and a second chosen margin;

[0019] - in the presence of the last option (or its variant), in its step, one can use predefined first and second margins;

[0020] - Alternatively, in the presence of the last option, in its step, one can use first and second margins which are a function of the first minimum and maximum values ​​transmitted at time t - dt.

[0021] The invention also proposes a computer program product comprising a set of instructions which, when executed by processing means, is suitable for implementing a control method of the type presented above, in a system comprising a client-server type architecture in which at least one server is suitable for transmitting first minimum and maximum values ​​of a quantity of a physical quantity that it can provide, and at least one client is suitable for generating and transmitting to the server a command between these first minimum and maximum values ​​so that it provides a quantity of physical quantity equal to this command, in order to control the provision of the quantity of physical quantity by the server.

[0022] The invention also provides a control device for equipping a system comprising a client-server architecture in which:

[0023] - at least one server is suitable for transmitting initial minimum values ​​and maximum amount of a physical quantity that it can provide, and

[0024] - at least one client is capable of generating and transmitting an instruction to the server between these first minimum and maximum values ​​so that it provides a quantity of physical quantity equal to this setpoint.

[0025] This control device is characterized in that it comprises at least one processor and at least one memory arranged to perform the operations consisting of, in the event of receiving the instruction by the server at a time t, to determine if this instruction is between the first minimum and maximum values ​​transmitted at a time t - dt, where dt is a duration representing a round-trip transmission time between the server and client, and if so, to authorize the server to provide a quantity of physical quantity equal to this instruction.

[0026] The invention also proposes a system comprising, on the one hand, a client-server type architecture in which at least one server is suitable for transmitting first minimum and maximum values ​​of a quantity of a physical quantity that it can provide, and at least one client is suitable for generating and transmitting to the server a setpoint between these first minimum and maximum values ​​so that it provides a quantity of physical quantity equal to this setpoint, and, on the other hand, a control device of the type of that presented above.

[0027] For example, this system can constitute a vehicle, possibly of the automobile type. Brief description of the figures

[0028] Other features and advantages of the invention will become apparent from an examination of the detailed description below, and the accompanying drawings, in which:

[0029] [Fig. 1] schematically and functionally illustrates an example of an embodiment of a system constituting a vehicle and comprising a control device according to the invention and a client-server architecture,

[0030] [Fig.2] schematically and functionally illustrates an example of an embodiment of a supervisory computer forming part of a server in the client-server architecture of [Fig.1] and comprising an example of an embodiment of a control device according to the invention, and

[0031] [Fig.3] schematically illustrates an example of an algorithm implementing a control method according to the invention. Detailed description of the invention

[0032] The invention aims in particular to propose a control method, and an associated DC2 control device, intended to allow control of the supply of a quantity qgp of a physical quantity by a server of a client-server type architecture of a system S.

[0033] In what follows, system S is considered, by way of non-limiting example, to be a motor vehicle. For example, a car, as illustrated in [Fig. 1]. However, the invention is not limited to this type of system. It relates to any type of system comprising a client-server architecture, with a server capable of providing a quantity of a physical quantity. Thus, it relates in particular to vehicles (land, sea (or river), and air), installations (possibly of an industrial type), electrical appliances (possibly consumer-grade), and buildings.

[0034] Furthermore, given the preceding choice, the following, by way of non-limiting example, considers that the client-server architecture comprises a server, including in particular a powertrain (or PWM) and a control unit (CU) responsible for supervising this PWM, and a client, including at least one client control unit (CU), for example responsible for controlling the movements of the vehicle S (possibly for a speed and distance control function between vehicles). Therefore, the physical quantity provided by the PWM is torque (in Nm).

[0035] But a system S can include other types of server and client. Furthermore, a server can be associated with several (at least two) clients, and a system S can include several independent client-server architectures.

[0036] A system S (here a vehicle) comprising a thermal powertrain transmission chain, a CS supervisory computer, a CC client computer, an RC internal communication network (possibly multiplexed), and a DC2 control device according to the invention, is schematically represented in [Fig.1].

[0037] It should be noted that the GMP could be of the all-electric type or of the hybrid type (electric and thermal).

[0038] As illustrated, the transmission chain also includes, here, a drive shaft AM, a coupling device DC1, a gearbox BV, and a transmission shaft AT.

[0039] The operation of the transmission chain (and therefore of the GMP) is supervised by the CS supervision computer (which is part of the server with the GMP).

[0040] Since the powertrain is purely thermal, by way of illustration, it comprises a thermal drive machine (MMT) including a crankshaft (not shown) which is fixedly attached to the drive shaft AM in order to rotate the latter (AM). This thermal drive machine MMT is designed to operate in a first mode to provide a physical quantity (here, torque), as instructed by the supervisory computer CS. Furthermore, it (MMT) is designed to be coupled to the gearbox BV via the coupling device DC1. The latter (DC1) is designed to deliver torque from the torque produced by the thermal drive machine MMT, specifically for at least one set Tl of drive wheels, when it is in its coupled position and therefore when it couples the thermal drive machine MMT to the gearbox BV.

[0041] For example, the coupling device DC1 can be a hydraulic circuit clutch. But it could be of another type.

[0042] Also, for example, the Tl train can be located in the forward PVV part of the Vehicle S. It is preferably, and as illustrated, coupled to the AT driveshaft via a DV differential (here, front). But in a variant, this T1 axle could be the one referenced T2, which is located in the rear PRV section of vehicle S.

[0043] The system S (here a vehicle) also has at least one function controlled by the client computer CC and designed to generate a setpoint cq defining the quantity of a physical quantity qgp that it wants the server to provide. Here, each setpoint cq is a pair and the function is, for example, a driver assistance function responsible for regulating the speed of the vehicle S and the distance between vehicles.

[0044] The CS supervisory computer is notably responsible for generating and transmitting, via the internal communication network RC and at least to the client computer CC, the first minimum values ​​vlmin and maximum values ​​vlmax of the quantity of physical quantity qgp that the server (here the GMP) can provide at the time considered.

[0045] For its part, the client computer CC is designed to generate and transmit to the server (and more specifically to the supervisory computer CS), via the internal communication network RC, a setpoint cq which is between the last first minimum values ​​vlmin and maximum values ​​vlmax transmitted by the supervisory computer CS. This setpoint cq represents the quantity of physical quantity qgp that the client computer CC would like the GMP to supply at the given time.

[0046] As mentioned above, the invention proposes in particular a control method intended to allow control of the supply of the quantity of physical quantity qgp by the server of the client-server architecture of the vehicle S.

[0047] This (control) method can be implemented at least partially by the control device DC2 (illustrated at least partially in Figures 1 and 2), which for this purpose comprises at least one PR1 processor, for example a digital signal processor (or DSP), and at least one MD memory. This control device DC2 can therefore be implemented as a combination of electrical or electronic circuits or components (or "hardware") and software modules (or "software"). For example, it could be a microcontroller.

[0048] The MD memory is random access memory (RAM) to store instructions for the implementation by the PR1 processor of at least part of the control process. The PR1 processor may comprise integrated (or printed) circuits, or several integrated (or printed) circuits connected by wired or wireless connections. An integrated (or printed) circuit is defined as any type of device capable of performing at least one electrical or electronic operation.

[0049] In the example illustrated, but not limited to, Figures 1 and 2, the DC2 control device is part of the CS supervisory computer. However, this is not mandatory. Indeed, the DC2 control device could comprise its own dedicated computer, which is then coupled to the CS supervisory computer, or could be part of another computer embedded in the S system (here a vehicle) and providing at least one other function, for example.

[0050] As illustrated non-limitingly in [Fig.3], the (control) method, according to the invention, includes a step 10-60 which is implemented each time the client wants to transmit a command cq to the server, and therefore the server (and more precisely its supervisory computer CS) transmits to the client (and more precisely to its client computer CC), via the internal communication network RC, a message containing first minimum values ​​vlmin and maximum values ​​vlmax.

[0051] Step 10-60 of the process therefore comprises, firstly, a substep 10 in which a message containing the initial minimum (vlmin) and maximum (vlmax) values ​​that the server (here the GMP) is able to provide at the given time is transmitted (the DC2 control device triggers the transmission) to the client computer CC via the internal communication network RC. Then, these initial minimum (vlmin) and maximum (vlmax) values ​​are stored corresponding to that given time in a memory of the DC2 control device or the CS supervisory computer.

[0052] Upon receiving the first minimum values ​​vlmin and maximum values ​​vlmax, the client (and more precisely its client computer CC) generates a setpoint cq which is between the first minimum values ​​vlmin and maximum values ​​vlmax received, then transmits to the server (and more precisely to its supervisory computer CS), via the internal communication network RC, a message containing this setpoint cq which it has just generated.

[0053] Step 10-60 of the process also includes a substep 20 in which, if the server receives the setpoint cq(t) at time t, the control device DC2 determines whether this setpoint cq(t) is between the first minimum values ​​vlmin(t-dt) and maximum values ​​vlmax(t-dt) transmitted at time t - dt (and previously stored). The duration dt here represents the round-trip transmission time between the server and the client.

[0054] Step 10-60 of the process also includes a substep 30 in which, when vlmin(t-dt) < cq(t) < vlmax(t-dt), the (control device DC2) allows the server to provide a quantity of physical quantity qgp which is equal to the setpoint cq transmitted by the client.

[0055] Thanks to this consideration of the round-trip transmission time, it is now possible to compare setpoints cq(t) and first values ​​vlmin(t-dt) and vlmax(t-dt) which correspond temporally, which makes it possible to use first ml and second m2 margins (which we will return to later) which actually correspond to what we want to allow and therefore to almost totally avoid the occurrence of a false detection.

[0056] At least two embodiments can be envisaged for the process (and therefore the control device DC2) depending on the duration dt used.

[0057] In a first embodiment, in substep 20, the control device DC2 can use a predefined duration dt. In this case, the duration dt is equal to a round-trip transmission time between the server and client that has been previously determined, for example, at the factory or test center (in the case of a vehicle S). For example, this predefined duration dt can be an average value determined from a large number of round-trip transmission time measurements, or the largest value from a series of round-trip transmission time measurements.

[0058] In a second embodiment, in substep 20, the control device DC2 can use a duration dt equal to the absolute value of the difference between a first instant i1 of transmission of the first minimum values ​​v1min and maximum values ​​v1max and a second instant i2 of reception of the setpoint cq, which was generated following the reception of these first minimum values ​​v1min and maximum values ​​v1max. In this case, a duration dt equal to i1l - i2l is used. Optionally, several durations can be calculated, and then the average value of these calculated durations can be determined to obtain the duration dt.

[0059] When, in substep 20, the comparison shows that the setpoint cq(t) is not between the first minimum value vlmin(t-dt) and maximum value vlmax(t-dt), step 10-60 of the process may include a substep 40, as illustrated non-limitingly in [Fig. 3]. In this substep 40, one (the control device DC2) can determine whether the transmitted setpoint cq is between a second minimum value v2min(t-dt), equal to the sum of the first minimum value vlmin(t-dt) transmitted at time t - dt and a first chosen margin ml, and a second maximum value v2max(t-dt), equal to the sum of the first maximum value vlmax(t-dt) transmitted at time t - dt and a second chosen margin m2. In other words, we determine if the condition v2min(t-dt) = (vlmin(t-dt) + ml) < cq(t) < v2max(t-dt) = (vlmax(t-dt) + m2) is verified.

[0060] In the affirmative, and therefore if we have v2min(t-dt) < cq(t) < v2max(t-dt), step 10-60 of the process may include, as illustrated non-limitingly in [Fig.3], a substep 50 in which we (the control device DC2) allow the server to provide a quantity of physical quantity qgp which is equal to the setpoint cq(t) transmitted by the client.

[0061] Conversely, if the negative is true, and therefore if cq(t) does not belong to the interval [v2min(t-dt), v2max(t-dt)], step 10-60 of the process may include, as illustrated non-limitingly in [Fig. 3], a substep 60 in which the control device DC2 considers that the server cannot satisfy the client's request cq(t). because it is smaller or larger than what the server can provide, including margin (ml or m2). In this case, the provision of a quantity of physical quantity qgp equal to cq(t) is refused (or prohibited or limited to the current minimum and maximum values) and the client is immediately informed, as this constitutes a failure situation.

[0062] Alternatively, the control device DC2 could, as early as substep 20, immediately determine whether the setpoint cq(t) is between the second minimum value v2min(t-dt) and the second maximum value v2max(t-dt). This means that the first minimum value vlmin(t-dt) initially incorporates the first margin ml and the first maximum value vlmax(t-dt) initially incorporates the second margin m2. In this case, the process does not include substeps 40 and 50.

[0063] It should be noted that in substep 40, predefined (and therefore constant) first ml and second m2 margins can be used. However, this is not mandatory. Indeed, in substep 40, first ml and second m2 margins could be used that are a function of the first minimum (vlmin(t-dt)) and maximum (vlmax(t-dt) values ​​transmitted at time t - dt. This option allows the first ml and second m2 margins that are permitted to be dynamically adapted to the current situation, thus further reducing the probability of a failure (or false detection). In the variant mentioned in the preceding paragraph, the first ml and second m2 margins are used in substep 20.

[0064] It should also be noted, as illustrated but not limited to [Fig. 2], that the CS supervisory computer (or the DC2 control device computer) may also include a mass memory MM1, in particular for storing each received setpoint cq(t) and the first transmitted minimum vlmin and maximum vlmax values ​​corresponding to their transmission time, as well as any intermediate data involved in all its calculations and processing. Furthermore, this CS supervisory computer (or the DC2 control device computer) may also include an IE input interface for receiving at least each received setpoint cq(t), for use in calculations or processing, possibly after having shaped and / or demodulated and / or amplified it, in a manner known per se, by means of a PR2 digital signal processor.Furthermore, this CS supervisory computer (or the DC2 control device computer) can also include an IS output interface, notably to deliver each message containing the first minimum values ​​vlmin and maximum values ​​vlmax and each message authorizing or prohibiting the use of a received setpoint cq(t).

[0065] It should also be noted that the invention also proposes a computer program product (or computer program) comprising a set of instructions which, when executed by processing means such as electronic circuits (or hardware), such as the PR1 processor, is suitable for implementing the control method described above to control the supply of the quantity of physical quantity qgp by the (a) server of system S.

Claims

Demands

1. A control method for a system (S) comprising a client-server architecture in which i) at least one server is capable of transmitting first minimum and maximum values ​​of a quantity of a physical quantity that it can supply, and ii) at least one client is capable of generating and transmitting to said server a setpoint between said first minimum and maximum values ​​so that it supplies a quantity of physical quantity equal to said setpoint, characterized in that it comprises a step (10-60) in which, if said setpoint is received by said server at time t, it is determined whether this setpoint is between first minimum and maximum values ​​transmitted at time t - dt, where dt is a duration representing a round-trip transmission time between said server and client, and if so, said server is authorized to supply a quantity of physical quantity equal to said setpoint.

2. Method according to claim 1, characterized in that in said step (10-60) a predefined duration dt is used, equal to a round-trip transmission time between said server and client previously determined.

3. Method according to claim 1, characterized in that in said step (10-60) a duration dt is used equal to an absolute value of a difference between a first instant of transmission of first minimum and maximum values ​​and a second instant of reception of a setpoint generated consecutively to the reception of these first minimum and maximum values.

4. A method according to any one of claims 1 to 3, characterized in that in said step (10-60) a first minimum value transmitted at time t - dt and incorporating a first chosen margin is used, and a first maximum value transmitted at time t - dt and incorporating a second chosen margin.

5. Method according to claim 4, characterized in that in said step (10-60) predefined first and second margins are used.

6. Method according to claim 4, characterized in that in said step (10-60) first and second margins are used as a function of said first minimum and maximum values ​​transmitted at said instant t - dt.

7. Product: computer program comprising a set of instructions which, when executed by processing means, is capable of putting implement the control method according to any one of claims 1 to 6, in a system (S) comprising a client-server type architecture in which i) at least one server is suitable for transmitting first minimum and maximum values ​​of a quantity of a physical quantity that it can supply, and ii) at least one client is suitable for generating and transmitting to said server a setpoint between said first minimum and maximum values ​​so that it supplies a quantity of physical quantity equal to said setpoint, to control the supply of said quantity of physical quantity by said server.

8. Control device (DC2) for a system (S) comprising a client-server architecture in which i) at least one server is capable of transmitting first minimum and maximum values ​​of a quantity of a physical quantity that it can provide, and ii) at least one client is capable of generating and transmitting to said server a setpoint between said first minimum and maximum values ​​so that it provides a quantity of physical quantity equal to said setpoint, characterized in that it comprises at least one processor (PR1) and at least one memory (MD) arranged to perform the operations consisting, in the event of reception of said setpoint by said server at a time t, of determining whether this setpoint is between first minimum and maximum values ​​transmitted at a time t -dt, where dt is a duration representing a round-trip transmission time between said server and client,and, if so, to authorize said server to provide a quantity of physical quantity equal to said instruction.

9. System (S) comprising a client-server architecture in which i) at least one server is capable of transmitting first minimum and maximum values ​​of a quantity of a physical quantity that it can supply, and ii) at least one client is capable of generating and transmitting to said server a setpoint between said first minimum and maximum values ​​so that it supplies a quantity of physical quantity equal to said setpoint, characterized in that it further comprises a control device (DC2) according to claim 8.

10. System according to claim 9, characterized in that it constitutes a vehicle.

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