DE102011003345A1 - Network interconnection system for vehicle control devices and / or for vehicle control devices and synchronization method for operation of the network interconnection system - Google Patents

Abstract

The invention describes a network system for vehicle control devices and / or for vehicle control devices, in particular in a motor vehicle, comprising at least two vehicle control devices and / or vehicle control devices, with a data processing program for controlling and / or regulating the associated vehicle control system and in each of the at least two vehicle control devices and / or vehicle control devices / or the vehicle control system is executed by a primary computing unit and / or a secondary computing unit, the at least two vehicle control devices and / or vehicle control devices having a bus connection to a common data bus and / or an internal data connection, with the common data bus and / or the internal data connection being connected to a The at least two vehicle control devices and / or vehicle control devices are exchanged information with one another and the loop time tL of at least one data processing program for a number n1,2 of Loo ps compared to a nominal loop time tL, n is shortened or lengthened by a period of time Δt in order to synchronize the arrival time of information in the vehicle control unit and / or vehicle control unit via the common data bus with an information arrival expectation window of the at least one data processing program, which is characterized in that the number n1,2 of loops is determined by means of an algorithm as a function of at least one item of information received via the common data bus and / or the internal data connection.

Description

The invention relates to a network interconnection system according to the preamble of claim 1, vehicle control devices and / or vehicle control devices according to the preambles of claims 19 and 24 and a synchronization method according to the preamble of claim 25.

Future vehicle systems are becoming increasingly interconnected and the exchange of information among these systems is increasing. At the same time, the number of electronic and electromechanical vehicle systems in current vehicles is steadily increasing, which also causes an increase in the information flow in the vehicle and a growing networking is necessary. An example of this are electromechanically actuated wheel brakes (EMB), which comprise, in addition to an electromechanical actuator, an electronic control and regulating device arranged in the region of the wheel. Likewise, a significant increase of environment sensors in motor vehicles can be observed, whose sensor signals must be evaluated by corresponding modules and, if necessary, can serve as a basis for decision for a control intervention by a braking device.

From the international patent application WO 2008/155341 A1 is a combined brake system with hydraulically actuated wheel brakes on a first axis and electromechanically actuated wheel brakes on a second axis known. In this case, the first vehicle axle is assigned an electrohydraulic control and regulation unit and each electromechanical actuator of the second axle has an electronic control unit. The control and regulation units are connected to each other via data buses.

In a classical functional partitioning of the hardware and software components, the associated processor-based control unit operates on the basis of sensor-based control. This regulation can make a maximum number of iterations (calculations) per second. For example, an iteration rate of 200 s ^-1 corresponds to a loop time of 5 ms. Actuating and control operations usually take place in the time frame of this loop time.

Different network devices usually also have different loop times. Whereas a motor control unit allows loop times from 4 ms to 64 ms, the classic ESP control unit (ESP: electronic stability program) uses a loop time of 10 ms. A novel electromechanical wheel brake actuator in turn works with a software loop time of 5 ms.

An example of a networked vehicle brake system is the WO 2008/155341 A1 , The disclosed brake system has an ESP unit as a central controller (master), which sends on the basis of its loop time communication messages to other devices (slaves) of the network (eg to the wheel control unit, WCU) and quasi per "Remote control" specifies the setpoints (eg for the braking force to be set). In this case, the valves (braking force) are no longer wheel-individually controlled directly (centrally). Instead, the ESP unit transmits the set clamping force on the basis of communication messages from the EMB, whereupon the respective EMB automatically adjusts the actual clamping force accordingly. The electric brake is thus part of a network interconnection system.

The not yet published German patent specification with the application number 10 2010 031 608.3 discloses a network comprising the control units of an EMB and a central electronic control unit (ECU). The ECU sends time stamped messages to the control units of the actuators, whereupon they make a phase adjustment of their own loop times to the arrival of the timestamps. The adaptation is achieved over a fixed number of shortened or extended loops.

An obvious disadvantage of networks described in the prior art is either the loose temporal relationship of the loop times of the individual network devices or the rigid and inflexible achievement of synchronization by means of a fixed predetermined number of shortened or extended loops. If the network devices are not or not yet matched to one another, a message sent by the master and received by a slave may possibly be disregarded for a certain time before the slave processes the message and possibly carries out a corresponding action since the currently executed iteration loop is still terminating must become. This delay is classified as safety-relevant in the event of a sudden request for braking: the braking process can be initiated late in a dangerous situation altogether, since, for example, a collision danger detected by an environmental sensor and the corresponding brake intervention are not immediately evaluated or implemented. In other cases, the tension setpoint values of a brake device can be adjusted at different times, which jeopardizes the stability of the vehicle during the braking process. In turn, adjusting loop times over a fixed number of shortened or extended loops, in many cases, unnecessarily increases the time it takes to achieve synchronization.

The invention is therefore based on the object to propose a network interconnection system in which a temporal coordination between the individual network devices depending on the detected time offset is implemented flexibly. Furthermore, associated vehicle control devices and / or vehicle control devices and a corresponding synchronization method are to be proposed.

This object is achieved by the network interconnection system according to claim 1, the vehicle control devices and / or vehicle control devices according to claims 19 and 24 and the synchronization method according to claim 25.

The network interconnection system for vehicle control devices and / or for vehicle control devices, which is used in particular in a motor vehicle, comprises at least two vehicle control devices and / or vehicle control devices, wherein in the at least two vehicle control devices and / or vehicle control devices each have a data processing program for controlling and / or regulating the associated vehicle control system and / or vehicle control system is executed by a primary computing unit and / or a secondary computing unit. The at least two vehicle control devices and / or vehicle control devices have a bus connection to a common data bus and / or an internal data connection, whereby an information exchange of the at least two vehicle control devices and / or vehicle control devices takes place via the common data bus and / or the internal data connection and wherein the loop Time t _{L of} at least one data processing program for a number n _1,2 of loops with respect to a nominal loop time t _{L, n} is shortened or extended by a time Δt, the arrival time of information in the vehicle control unit and / or vehicle control unit via the common data bus and / or to synchronize the internal data connection with an information arrival expectation window of the at least one data processing program. The network network system according to the invention is characterized in that the number n _1,2 of loops is determined by means of an algorithm as a function of at least one information received via the common data bus and / or the internal data connection.

If the loop time of a data processing program of a vehicle control device and / or vehicle control device is variable, a relative shift of the loop time and thus of the information arrival expectation window in an information receiving device relative to the information transmitting device can be achieved. Since received information can only be processed essentially without any time delay if it falls into the information arrival expectation window, there is the advantage that dead times of the information processing are eliminated or significantly shortened as soon as the sending and the receiving device are synchronized.

Thus, the disadvantage is solved that devices that communicate with each other unsynchronized in a network receive information from other network devices at random times. In this case, a receiving device will still complete the current loop before it can respond to the received information, even though it already exists. Especially with safety-critical control devices, such. As an ESP controller, however, the rapid processing and implementation of information is of great importance.

By shortening or lengthening the nominal loop time t _{L, n of} the receiving device for an algorithm-determined number n _1,2 of loops by a time Δt, a stepwise approach and synchronization of the communicating network devices is achieved. As soon as the synchronization is achieved, ie as soon as received information arrives in the information arrival expectation window, the loop time is again set to the value of the nominal loop time t _{L, n} . The devices are now synchronized.

The particular advantage that results from the use of the algorithm for determining the number n _1,2 of shortened or extended loops is that a synchronization is achieved which is adapted to the respectively actually present phase offset, whereby it can additionally be taken into account that that there may be an upper limit to the duration of the period Δt, which depends on the nominal loop time of the corresponding device and its sensitivity to clock variations. The actual phase offset is detected by comparing the time of arrival of information with the time of occurrence of the information arrival expectation window. Based on the detected phase offset, the algorithm, taking into account Δt, determines a largely optimal number n _1,2 of shortened or extended loops, which leads to the rapid achievement of synchronization without an excessive error rate in the information processing of the data processing program to be synchronized by excessive clock fluctuations Effect device.

Preferably, it is also provided that the time interval .DELTA.t is determined by means of an algorithm as a function of at least one information received via the common data bus. The algorithm for determining the Time span Δt can be the same algorithm that determines the number n _1,2 of shortened or extended loops, or an independent algorithm that interacts with the algorithm for determining n _1,2 . Due to the respective flexibly determined time interval .DELTA.t, which is determined in dependence of the received information and thus in dependence of the detected phase offset, in connection with the flexibly determined number n of changed loops _1.2 a largely ideal, because flexible adaptation of the clock cycles of the communicating Devices possible.

In a further preferred embodiment, it is provided that the information used to determine the number _n1,2 of loops and / or to determine the time span Δt contains at least one information item received via the common data bus. By sending information with a time stamp from a master (main control unit) to a slave (sub-control unit), the slave receives time or clock information of the master, which can be used to determine the phase offset.

In particular, it is advantageous that the information with a timestamp additionally comprises further data. As a result, any information sent anyway by the main control unit can be used simultaneously for sending time stamps. In addition, a timestamp may advantageously be located at a particular position within the transmitted message, thereby transporting timing information to the receiver. In this case, the timestamp can either serve as a pure marking of a previously agreed position in the clock cycle of the master (for example, start of the cycle) or else contain relative information about the position in the clock cycle at which it was sent ( for example, the offset to the beginning of the cycle). In addition, there is the advantage that the transmission of possibly safety-critical information by the main control unit must not be interrupted in order to send a separate information with timestamp at a specific position in the clock cycle.

It is also particularly preferred that information with a time stamp of at least one of the at least two vehicle control devices and / or vehicle control devices via the common data bus to at least one of the at least two vehicle control devices and / or vehicle control devices periodically, in particular zeitäquidistant shipped. By periodically sending timestamps, it is no longer necessary for the timestamp to contain information about its transmission time in the clock cycle of the master. The timestamp is always sent at a fixed time. If the receiving devices have the information necessary in this case, which time is marked in the clock cycle of the master, the time stamp can be kept small in terms of their data size, since it does not have to transport additional information. Timestamps can be sent from more than one device on the network and can be received and processed by more than one device on the network. This favors the synchronization of networks with a larger number of network devices.

In particular, it is expediently provided that the information with a time stamp from a data bus with its own loop time, in particular a Flexray bus, to at least two vehicle control units and / or vehicle control units periodically, in particular zeitäquidistant shipped. This has the advantage that the time stamps do not have to be created and sent by a device in the network, whereby no computing time of this device is deducted from its actual main task for synchronization purposes of other devices. In addition, of course, all network devices have a direct or at least indirect connection to the data bus, which synchronization information can be transferred from the data bus particularly fast and effective to the network devices. Looping through synchronization information via one or more network devices is not necessary in this case, provided that all network devices are provided with a primary computing unit. For network devices with a secondary computing unit, the number of upstream devices through which the synchronization information must be looped through can advantageously be reduced.

Moreover, it is advantageous that the information is sent periodically, in particular temporally equidistant, with a time stamp from an external trigger via the common data bus to at least two vehicle control devices and / or vehicle control devices. Also in this case offers the advantage that the free computing time of a main control unit is not limited by the creation and sending of synchronization information.

According to a further preferred embodiment of the invention, it is provided that the time period .DELTA.t is limited to a limited and / or filtered measure. By this limitation to a maximum value for the period .DELTA.t can be avoided excessive change in the predetermined clock frequency. Excessive change can lead to an increased error rate in the data processing of the device.

According to a particularly preferred embodiment, it is provided that the time period .DELTA.t is limited to 1% of the loop time. The limitation to 1% does not essentially lead to an increased error rate. Nevertheless, it allows synchronization of the network devices within a short period of time.

In addition, it is provided that a vehicle control unit specifies a desired value for a vehicle device to be controlled and / or regulated. Vehicle control devices offer the advantage that they are relatively simple and inexpensive, since they have no feedback loop from the device to be controlled and read no actual values. A vehicle control device may be, for example, a control device for an electric motor, which controls the electric motor by means of a current to a setpoint speed taken from a characteristic curve.

Furthermore, it is provided that a vehicle control device reads an actual value from a vehicle device. This makes it possible to read out and check the actual state of a vehicle device.

In particular, it is provided that a vehicle control device compares the deviation of a setpoint value for a vehicle device to be controlled and / or regulated with an actual value of the vehicle device to be controlled and / or regulated and adapts the actual value to the setpoint value. Only by comparing a desired value with an actual value can a regulation of the corresponding vehicle device take place. This is an important prerequisite for much of the essential vehicle equipment, such. B. engine and brakes.

• – Fahrzeugbremseinrichtung,
• – Motorregeleinrichtung
• – Fahrwerksregeleinrichtung,
• – Getrieberegeleinrichtung,
• – Elektro-Differential-Einrichtung,
• – Elektromotorregeleinrichtung,
• – Optische Sensoreinrichtung und
• – Entfernungssensoreinrichtung

ist, welche mittels des Fahrzeugsteuergeräts und/oder Fahrzeugregelgeräts an den gemeinsamen Datenbus angebunden ist. Diese Einrichtungen werden von entsprechenden Steuer- bzw. Regelgeräten kontrolliert. Zudem ist in modernen Fahrzeugen zunehmend eine Vernetzung der einzelnen Fahrzeugsteuergeräte und/oder Fahrzeugregelgeräte gegeben. Eine Synchronisation der vernetzten Geräte ermöglicht daher einen schnelleren Informationsaustausch und ein effektiveres Zusammenwirken der einzelnen Geräte untereinander.Furthermore, it is preferable for a vehicle device to be a device from the group:

• Vehicle brake device,
• - Motor control device
• - chassis control device,
• - transmission control device,
• - Electro-differential device,
• Electric motor control device,
• - Optical sensor device and
• - Distance sensor device

is, which is connected by means of the vehicle control unit and / or vehicle control device to the common data bus. These devices are controlled by appropriate control devices. In addition, in modern vehicles increasingly networking of the individual vehicle control devices and / or vehicle control devices is given. A synchronization of the networked devices therefore allows a faster exchange of information and a more effective interaction of the individual devices with each other.

In a further preferred embodiment of the invention, it is provided that a vehicle control device and / or vehicle control device having a primary computing unit has a direct bus connection to the common data bus. This results in the advantage that the vehicle control device and / or vehicle control device via the direct bus connection has direct access to synchronization information and time stamps, which are preferably sent via the common data bus.

In addition, it is advantageous that a vehicle control device and / or vehicle control device with a secondary computing unit has a separate data connection, in particular a serial peripheral interface or a parallel interface, to a vehicle control device and / or vehicle control device, which transmits the information with a time stamp via the common Data bus sends and / or receives. Synchronization information and timestamps can be forwarded in this way from the device with the direct bus connection to the device with the secondary computing unit, whereby the device with the secondary computing unit can be synchronized to a main controller used in the network as a master master. The advantage of this separate data connection arises especially for network devices that communicate mainly with only one other network device (which has a direct connection to the common data bus). Thus, the traffic between the device with the primary computing unit and the device with the secondary computing unit is not routed over the common data bus, thereby occupying there no bandwidth that can be used for the communication of several other network devices.

It is expediently provided that the secondary computing unit is a coprocessor which is arranged in the housing of a primary computer unit and is connected to the primary computer via an internal data connection, in particular RAM data exchange, chip timers, interrupts and / or suitable hardware peripherals. This has the advantage that a secondary computing unit, which interacts closely with a primary computing unit anyway, is particularly effectively coupled to the primary computing unit.

Furthermore, it is preferred that the common data bus is a Flexray bus, CAN bus, LIN bus, MOST bus or Ethernet bus. Depending on which of the listed embodiments is used, there are different advantages in particular of particularly fast data transmission up to the possibility to use the self-clock frequency of the bus for synchronization of the network devices.

It is expediently provided that the information provided with a time stamp is determined and / or formed by at least two vehicle control devices and / or vehicle control devices. This results in the advantage that multiple network device, which may work with different loop times, other network devices can synchronize to a common, usable by all devices clock frequency. Thus, in the case of different loop times of individual devices advantageously a synchronization of the entire network interconnection system allows.

Moreover, it is advantageous that at least one of the at least two vehicle control devices and / or vehicle control devices is neither associated with an electromechanical actuator of a wheel brake nor the nominal loop time t _{L, n of} the data processing program executed in this vehicle control device and / or vehicle control device for changing the nominal loop Time t _{L, n of} the data processing program of a second of the at least two vehicle control devices and / or vehicle control devices is used.

The present invention further relates to a vehicle control device and / or vehicle control device which is used in particular in a motor vehicle and in which a data processing program for controlling and / or regulating a vehicle function is executed by a primary calculation unit and / or a secondary calculation unit. The vehicle control device and / or vehicle control device has a bus connection for a data bus and / or an internal data connection, the vehicle control device and / or vehicle control device exchanging information with at least one further vehicle control device and / or vehicle control device via the data bus and / or the internal data connection. Furthermore, the vehicle control device and / or vehicle control device comprises synchronization means which shorten or extend the loop time t _{L of} the data processing program for a number n _1,2 of loops with respect to a nominal loop time t _{L, n} by a time interval Δt by the arrival time of Synchronize information in the vehicle control unit and / or vehicle control unit via the data bus and / or the internal data connection with an information arrival expectation window of the data processing program. The vehicle control device and / or vehicle control device is characterized in that an algorithm determines the number n _1,2 of loops as a function of at least one information received via the data bus and / or the internal data connection. The advantage of the vehicle control device according to the invention and / or vehicle control device is that it can perform an adaptation of its own clock frequency to an external clock specification based on received information. Thus, the vehicle control unit and / or vehicle control unit can synchronize to another vehicle control unit and / or vehicle control unit, which has the function of a master or main control unit in the network.

Preferably, the vehicle control device and / or vehicle control device is characterized in that the device comprises time mark setting means, which set the time of arrival of information without time stamp as a time stamp. This results in the advantage that any incoming information can be used to synchronize its own loop time to an external signal source. This also allows independent synchronization of a slave or sub-control unit to a master or to a main control unit, without the master has to spend their own computation time for creating and sending time stamps. Also, the available bandwidth of a data bus is not limited in this case by the transmission of timestamps.

In a further preferred embodiment of the invention, it is provided that the device, in particular exclusively, immediately after receiving an information with a time stamp or setting the arrival time of information without timestamp as a timestamp in turn sends information. This results in the advantage that the time interval between sending this message and sending a message with a timestamp is as large as possible, which collisions of the messages without timestamp and timestamp can be avoided with each other. In addition, the main control unit thereby receives a feedback on the reception and possibly the processing of the information with timestamp by the sub-control unit.

Moreover, it is advantageous that the vehicle control device and / or vehicle control device sends information with a time stamp via the bus connection for the common data bus. This offers the advantage that the device in turn can synchronize other sub-controllers in conjunction with a main control unit. Advantageously, it is possible to synchronize a plurality of network devices, which possibly operate with different loop times, to a common clock frequency which can be used by all devices.

Furthermore, it is advantageous that the nominal loop time t _{L, n of} the data processing program serves as a time base for sending information with time stamps and / or as a time base for setting the time mark within a sent information with timestamp. Thus, the loop time of the device is set as the clock frequency for other network devices to which they can synchronize.

The present invention further relates to a vehicle control device and / or vehicle control device which is used in particular in a motor vehicle and in which a data processing program for controlling and / or regulating a vehicle function is executed by a primary calculation unit and / or a secondary calculation unit. The vehicle control unit and / or vehicle control unit has a bus connection for a common data bus and / or an internal data connection, the vehicle control unit and / or vehicle control unit exchanging information with at least one further vehicle control unit and / or vehicle control unit via the common data bus and / or the internal data connection wherein the vehicle control system and / or vehicle control system sends information with a timestamp via the bus connection for the common data bus and / or the internal data connection. The vehicle control device and / or vehicle control device is characterized in that the nominal loop time t _{L, n of} the data processing program serves as a time base for sending information with time stamps and / or as a time base for setting the time mark within a sent information with timestamp. As a result, the vehicle control device and / or vehicle control device can assume the function of a main control device in the networked network system and send synchronization information to other network devices. The achievable synchronization in the network system leads to the advantages already described.

Furthermore, the present invention also relates to a synchronization method for operating a network network system for vehicle control devices and / or for vehicle control devices, which is used in particular in a motor vehicle application. The network interconnection system comprises at least two vehicle control devices and / or vehicle control devices, wherein in each of the at least two vehicle control devices and / or vehicle control devices, a data processing program for controlling and / or regulating the associated vehicle control system and / or vehicle control system is executed by a primary computing unit and / or a secondary computing unit. The at least two vehicle control devices and / or vehicle control devices have a bus connection to a common data bus and / or an internal data connection, whereby an information exchange of the at least two vehicle control devices and / or vehicle control devices takes place via the common data bus and / or the internal data connection and wherein the loop Time t _{L of} a data processing program of at least one vehicle control device and / or vehicle controller for a number n _{1, 2} of loops with respect to a nominal loop time t _{L, n} is shortened or lengthened by a time Δt to reduce the arrival time of information in the vehicle control unit and / or vehicle controller to synchronize over the common data bus and / or the internal data connection with an information arrival expectation window of the at least one data processing program. The synchronization method is characterized in that the number n _1,2 of loops is determined by means of an algorithm as a function of at least one information received via the common data bus and / or the internal data connection. The advantage of the synchronization method is that a synchronization of several network devices communicating with each other is achieved, whereby communication dead times can be substantially avoided. Moreover, the method offers the same advantages as the network network system according to the invention already described.

Furthermore, it is advantageous that the nominal loop time t _{L, n} for a number n ₁ of loops is shortened by a time interval Δt, if the following applies: Δt · n ₁ <Δt · n ₂ .

Since in this case a synchronization by a shortening of the nominal loop time t _{L, n} can be achieved faster than by an extension of the nominal loop time t _{L, n} , this method step allows a production of the synchronization of an understeer device to a substantially as fast as possible main control unit.

Preferably, the method according to the invention is characterized in that the nominal loop time t _{L, n} for a number n ₂ of loops is extended by a time interval Δt, if the following applies: Δt · n ₁ > Δt · n ₂ .

In this case, synchronization is achieved faster by extension instead of shortening the nominal loop time t _{L, n} . Thus, also carrying out this method step essentially leads to the fastest possible synchronization of an understeer device to a main control device.

In a further preferred embodiment of the invention, it is provided that the number n _1,2 of loops, shortened or extended by the time interval Δt, is executed immediately after each other before the loop time returns to the value of the nominal loop time t _{L, n is} set. By executing the shortened or extended number n _1,2 of loops without intermediate reset to the value of the nominal loop time t _{L, n} , the synchronization process is accelerated, since pauses in the "winding" are avoided.

Further preferred embodiments will become apparent from the subclaims and the following descriptions of exemplary embodiments with reference to figures.

Show it

1 1 schematically illustrates a method for operating an electronic brake system in a preferred embodiment;

2 a braking system in a preferred embodiment, with the method of 1 is operated,

3 a motor vehicle with a brake system according to 2 .

4 2 schematically shows a detail of a network interconnection system consisting of two vehicle control devices with a total of a primary calculation unit and a secondary calculation unit,

5 schematically a vehicle control unit with a primary computing unit and a secondary computing unit, which are arranged in the same housing,

6 schematically a vehicle control unit with only a primary computing unit,

7 schematically a hydraulic brake system,

8th schematically a network interconnection system comprising transmission control, suspension controller and brake control devices,

9 the phase offset of a main controller to a sub-controller across multiple loops and

10 the loop time of a sub-controller during a synchronization process.

Identical objects are provided with the same reference numerals in all figures.

At the in 1 exemplified methods for operating a brake system are exchanged between a main control unit (master, not shown) and a sub-control unit (slave, not shown), messages. Shown are the time axis associated with the main control unit 70 , on which the time t _{SG1 is} plotted, as well as the time axis associated with the sub-control unit 76 on which the time t _{SG2 is} plotted. In both cases, the loop times are also indicated, t _SL1 for the main control unit and t _SL2 for the sub-control unit.

The main controller sends questionnaires to the sub-controller at regular intervals 90 . 91 . 92 . 93 , The sub-controller sends response messages 96 . 97 . 98 . 99 to the main control unit.

The questionnaires sent from the main controller are to be the sub-controller in the information arrival expectation window 106 to reach. Information arrival expectation window 106 is designed so that questionnaires that reach the sub-controller within that window can be handled immediately and essentially without delay.

The data bus is at the in 1 illustrated method designed as a CAN bus. When using a CAN-based network, the periodic (in particular time-equidistant) sending of messages by the master, in this example an ESP control unit, is used for synchronization, for example. The continuous, evenly spaced questionnaires 90 . 91 . 92 . 93 serve equally the data transmission and the setting of time marks.

These periodically received from the sub-control unit and other slaves (other acting as sub-controllers control units) questionnaires 90 . 91 . 92 . 93 are evaluated with respect to their time of arrival relative to the software loop time t _SL2 and with the (predetermined) desired arrival time window or information arrival expectation window 106 adjusted. A time offset is compensated by a corresponding successive adjustment of the loop time t _SL2 until the ideal phase reference of the loop time of the sub-controller to the loop time of the main controller is established. Thus, the transmission latency is minimal, the reaction speed maximum, the phase offset virtually constant, the application of controller coefficients of a controller with respect to the route is simplified and it is the best control performance achieved, which means shortest braking distances.

By way of example, the loop time can be set and generated via a timer, which is implemented as a hardware module of a microcontroller. If needed in the direction of the information arrival expectation window, the timer can be converted to a limited extent in its counting mode / mode of operation for a limited duration. This can be achieved, for example, by means of a modified minimum / maximum value and / or an adapted counting speed.

To make sure that the messages acting as time markers - questionnaires 90 . 91 . 92 . 93 - do not collide with other messages, In the present exemplary embodiment, a collision-free communication method is used. For this purpose, a question-answer-deadtime-question-answer-deadtime -... principle is used. As 1 is removable, the master sends each a questionnaire 90 . 91 . 92 . 93 (Request) of defined length in equidistant intervals - this is also called "timebased transmission" (time-based transmission of requests). The slave sends a response message 96 . 97 . 98 . 99 (Response), also of defined length, immediately after receiving the request message or questionnaire 90 . 91 . 92 . 93 - This is called "eventbased transmission" (event-based transmission of responses). The duration of sending the response or response message 96 . 97 . 98 . 99 never exceeds the duration of the pause between requests or questionnaires 96 . 97 . 98 . 99 , This ensures that requests and responses never collide, which actively supports synchronization.

In order to synchronize the main _controller loop time t _SL1 and the sub _{controller ECU} software loop time t _SL2, the subcontroller shortens its loop time t _SL2 each cycle until the message representing / containing the time stamp is within its (predetermined) time of arrival. desired information arrival expectation window 106 lies. Shown are four cycles 116 . 118 . 120 . 122 whose time length corresponds in each case to the loop time t _SL2 . In the first cycle 116 shortens control unit 2 its software loop time t _SL2 by 0.1 ms from 10 ms to 9.9 ms. This ensures that the point in time at which the sub-control unit questionnaire 91 receives, moves backward relative to the beginning of its cycle. Further time shifts of 0.1 ms take place in cycles 118 and 120 instead of.

In the fourth cycle, cycle 122 , reaches question message 93 the sub-controller in the information arrival expectation window 106 , Since the loop times t _SL1 and t _SL2 match in the present case, the reception of the question messages also takes place in the information arrival expectation window in the subsequent cycles 106 , The algorithm for monitoring and possibly recovering the synchronization is ideally permanently active. An adaptation is initiated as needed if a loss of synchronization (the questionnaires left the information arrival expectation window) was detected. This may be necessitated by unavoidable causes such as frequency inaccuracies due to component tolerances of the clocking components (quartz), quartz frequency drifts due to temperature variations, short-term local or global power failures (eg, a loose contact on the plug) in one or more controllers. The regular case of a necessary synchronization is the "synchronization" after the cold start / initial start of the vehicle (switching on the ignition), in which the network system was previously disabled / off / dormant.

In other applications, the loop time t _SL2 may also be extended over a number of cycles to achieve alignment of arrival time and information arrival expectation windows. Also combinations of extensions and shortenings are possible.

As related to 1 explained, the loop time is briefly extended or shortened to synchronize the loop time of the regulatory data processing program (sub-control unit) to the external time stamps (CAN messages) sent by the main control unit. Thus, a kind of "winding effect" of the time bases of the two control devices is achieved with each other. The temporary. extended or shortened loop time within cycles 116 . 118 . 120 (characterized by a brace 112 ) is varied to a negligible time frame (≈ 1%).

In 2 is braking system 50 shown in a preferred embodiment. braking system 50 essentially comprises actuator unit 1 on, by means of brake pedals 2 is operable. operating unit 1 in turn consists of vacuum brake booster 3 and vacuum brake booster 3 downstream master cylinder 4 , with which by means of hydraulic line 6 electrohydraulic control unit 5 connected is. To electrohydraulic control unit 5 are by means of hydraulic lines 15 . 16 hydraulically operated wheel brakes 7 . 8th connected in the example shown a first vehicle axle, z. B. front axle, are assigned.

As 2 is further removed, are a second vehicle axle, z. B. the rear axle, wheel brakes 9 . 10 assigned, whose operation in accordance with the hydraulically actuated wheel brakes 7 . 8th controlled hydraulic pressure by electromechanical actuators 11 . 12 he follows. The mentioned hydraulic pressure is determined by means of pressure sensors, not shown, in electrohydraulic control unit 5 are integrated. Based on this pressure value electromechanically actuated wheel brakes 9 . 10 driven, ie taking into account a braking force distribution function between the front and rear axle is a clamping force of wheel brakes 9 . 10 set. In addition, electromechanically actuated brakes 9 . 10 according to the actuation path of brake pedal 2 , ie according to the driver delay request to be controlled. For this purpose, the actuation of brake pedal 2 with the help of preferably redundant executed pedal travel sensor 22 determined. The control of the rear axle associated wheel brakes 9 . 10 becomes decentralized by an electronic control and regulation unit 19 . 20 performed.

As in 2 is indicated only schematically, is shown braking system 50 equipped with a parking brake functionality, for example. For this purpose have electromechanically actuated wheel brakes 9 . 10 Parking brake devices, not shown, with which wheel brakes 9 . 10 can be locked in the clamped state. The parking brake devices are by means of control 14 controllable, the z. B. is designed as a button and has three switch positions for the commands "clamping", "neutral" and "release".

For example, the output signals from the pedal travel sensor become 22 via signal line 17 another electronic control unit 18 fed, which can be formed for example by a chassis controller. Control unit 18 is an optional component of braking system 50 which can be dispensed with. signal line 17 may be formed in this case as two separate signal lines, the one signal line directly with electronic control unit 19 and the other signal line directly with electronic control unit 20 connected is.

high-speed bus 23 forms a direct connection between electro-hydraulic control unit (HECU) 5 and another (optional) electronic control unit 18 that by means of further high-speed bus 24 with electronic control unit 19 of electromechanical actuator 11 is directly connected. High-speed buses 23 and 24 are in one embodiment of the brake system without control unit 18 usually identical. signal line 28 serves the signal transmission between parking brake control element 14 and electrohydraulic control unit (HECU) 5 using high-speed bus 25 with electronic control unit 20 of electromechanical actuator 12 is directly connected, so that the output signals of parking brake control element 14 from said electronic control unit 20 be supplied. high-speed bus 26 forms a direct connection between electronic control units 20 and 19 electromechanical actuators 12 and 11 ,

Dashed line drawn 27 represents an optionally existing line to possibly further control and regulating units. With the reference numeral 29 All power supply connections are the in 2 referred to elements.

Alternatively, it is possible (not shown in a figure) that no electronic control unit 18 is present and the signal transmission between pedal travel sensor 22 and electronic control units 19 and 20 of electromechanical actuators 11 . 12 happens over signal lines while HECU 5 directly via a high-speed bus with electronic control unit 19 of electromechanical actuator 11 connected is.

At high speed buses 23 to 26 is, for example, a Flexray data bus.

motor vehicle 60 with in 2 represented brake system 50 and with control unit 5 is in 3 shown. wheel brakes 7 and 8th (not shown) are hydraulic, wheel brakes 9 and 10 (not shown) are electromechanically actuated.

In 4 is a schematic section 218 of a network interconnection system, which primary computer unit 207 and secondary calculator 206 includes. The two arithmetic units are assigned in this embodiment, an environment detection system, wherein primary computing unit 207 performs image processing software of a camera sensor and secondary processing unit 206 the software executes a radar-based proximity sensor. About bus 205 is primary calculator 207 , which has the network status of an understeer, is connected to a master vehicle control unit and receives information sent by the master with timestamps. The time stamps are used to synchronize the loop time of the image processing software on the primary computing unit 207 , About bus 210 is primary calculator 207 also connected to another sub-control unit. Da secondary unit 206 is also assigned to the surroundings detection system, has secondary processing unit 206 via no own connection to a common data bus. Instead, it is secondary calculator 206 via internal data connection 208 at primary calculator 207 tethered (not shown). Thus, the information sent by the master with timestamps via internal data connection 208 of primary calculator 207 at secondary unit 206 be continued.

5 schematically shows vehicle control unit 217 with primary calculator 207 and secondary calculator 206 which are in the same housing 209 are arranged. In this embodiment, vehicle control unit 217 an engine control unit in which primary computing unit 207 executes a program for engine control and engine control. Secondary processing unit 206 is a co-processor to primary calculator 207 and can via internal data connection 208 , which is realized by a shared RAM, for example, of the primary computing unit 207 access processed data. As primary calculator 207 over bus 205 Time stamps for the synchronization of the loop time receives, can also co-processor 206 on the basis of the primary calculation unit 207 received timestamps make a synchronization of its own loop time. bus 210 serves the forwarding of the time stamps sent by the master to other sub-control devices (not shown).

6 schematically shows a as the main control unit 200 Serving vehicle control unit with only one primary computing unit 207 , Primary processing unit 207 periodically sends timestamps over buses 210 to sub-controllers in the network (not shown). The time stamps are either sent as individual information or sent embedded in information with further data. The reception of the timestamps by the slaves allows them to receive their informational arrival expectation windows 106 to synchronize to the reception of information sent by the master.

In 7 For example, a hydraulic brake system is shown schematically. Brake control unit 200 has the function of a main controller in a network system whose slaves are not shown. Via hydraulic lines 204 controls and regulates brake control unit 200 arranged on the vehicle wheels hydraulic brake actuators 203 , bus 205 is used to transmit timestamps from the brake control unit 200 to sub-controllers existing in the network.

8th schematically represents a network interconnection system whose main control unit in this example as an electro-hydraulic brake control unit 200 is executed. On the front wheels of a vehicle arranged hydraulic brake actuators 203 be via hydraulic lines 204 directly from brake control unit 200 regulated. About buses 205 are also sub-controllers 201 (Transmission control and optical sensor device) and sub-control devices 202 (Electro-mechanical brake control devices, which are assigned to the rear wheels of a vehicle) communicatively with the brake control unit 200 coupled. bus 210 additionally provides a data link between electromechanical brake control units 202 ready. Brake control unit 200 shipped via buses 205 Timestamps to the transmission control and the optical sensor device (sub-control devices 201 ). These timestamps are used in sub-controllers 201 for the synchronization of information arrival expectation windows 106 with incoming information. To the electro-mechanical brake control units (sub-controllers 202 ) ships main controller 200 no time stamps, but still tax information at regular intervals. The time of arrival of this control information is in sub-controllers 202 marked with a timestamp. These timestamps set by the sub-controllers themselves serve to synchronize sub-controllers 202 with the arrival of information from main controller 200 , In this way, synchronization can be achieved without requiring special timing information from main controller 200 to understeer devices 202 be shipped. Thus, the traffic between main ECU 200 and sub-controllers 202 not unnecessarily increased, which is particularly advantageous in the case considered by interacting brake control units, since there is already a high exchange of information for brake control and brake control anyway. In addition, brake control and regulation information is safety-critical information, so that at any time sufficient free data bandwidth for their transmission must be available. About the information exchange on bus 210 can be electromechanical brake control devices 202 also cause a synchronization with each other. The synchronization process is completed within a few loops. If, for example, a typical loop time of 10 ms is assumed and a maximum possible phase offset of 5 ms is determined, a synchronization can be achieved within a period of 0.5 s if the loop time is shortened or extended by 1% ,

According to one embodiment, information includes optical sensor means 201 the warning that there is an obstacle on the road. This warning information is (not shown) implemented in a higher-level safety control device in a delay information, which in the form of a required reduction of the target engine torque to the engine control unit (not shown) and in the form of a required increase in the target brake pressure to the brake control unit 200 is sent. In this example, therefore, the information passes through the transmission path from the optical sensor device through a higher-level safety control device to the engine control unit or to the brake control unit. Since idle times can occur in each of the devices involved in the transmission path due to phase displacements of the loop times, a safety-critical response delay can be produced by adding up all dead times. By synchronization of the individual network devices, this is avoided according to the example, however.

9 shows the exemplary phase offset ∂ a main controller to a Understeer over four loops. At the beginning of the synchronization process, a phase offset ∂ _{1 of} the master to the slave is detected. This phase offset is made by the slave by comparing the time of arrival of a timestamp with the time of occurrence of an information arrival expected window 106 recognized. An algorithm executed in the slave determines on the basis of the detected phase offset ∂ that a shortening of the loop time by a value Δt across three loops (represented by steps 212 . 213 . 214 ) is sufficient to adjust the phase difference to a value within the tolerance band 211 to minimize. The width of tolerance band 211 is essentially determined by the width of the information arrival expectation window 106 ,

In 10 is the loop time t _{L of} an understeer device to see during a synchronization process. At the beginning of the synchronization process, a phase offset is detected, which leads to a main control unit by extending the nominal loop time t _{L, n} by Δt across a loop to achieve synchronization of the sub-controller. Accordingly, nominal loop time t _{L, n} 215 for a loop by Δt to t _{L, n} + Δt 216 elevated. This results in a shift of the loop time of the sub-controller to the loop time of the main controller, thereby achieving synchronization. After the synchronization has been established, for example, after a loop, the loop time t _{L is} again set to the value of the nominal loop time t _{L, n} 215 reduced.

LIST OF REFERENCE NUMBERS

1

operating unit

2

brake pedal

3

Vacuum brake booster

4

Master Cylinder

5

electrohydraulic control unit

6

hydraulic line

7, 8, 9, 10

wheel brake

11, 12

electromechanical actuator

14

Parking brake control element

17

signal line

18, 19, 20

electronic control unit

22

Pedal travel sensor

23, 24,

25, 26

high-speed bus

27

line

28

signal line

29

Power connectors

50

braking system

60

motor vehicle

70

Timeline of control unit 1

76

Timeline of control unit 2

90, 91, 92, 93

question Embassy

96, 97, 98, 99

reply message

106

Information arrival expectation window

112

brace

116, 118

cycle

120, 122

cycle

t _SG1

Time from controller 1

t _SG2

Time from controller 2

t _SL1

Software loop time from controller 1

t _SL2

Software loop time from controller 2

200

Main control unit (master)

201

Understeer device (slave)

202

interconnected sub-controllers

203

hydraulic brake actuator

204

hydraulic line

205

Data bus to a main control unit (master)

206

Secondary processing unit

207

Primary processing unit

208

internal data connection

209

common housing

210

Data bus between two sub-controllers (slaves)

211

tolerance band

212, 213, 214

stages

215

nominal loop time

216

extended loop time

217

Engine control unit

218

Detail of a networked network system

t _L

Loop time

∂, ∂ ₁ , ∂ ₂ , ∂ ₃ , ∂ ₄

phase displacement

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2008/155341 A1 [0003, 0006]
• DE 102010031608 [0007]

Claims (25)

Network interconnection system for vehicle control devices and / or for vehicle control devices, in particular in a motor vehicle, comprising at least two vehicle control devices and / or vehicle control devices, wherein in the at least two vehicle control devices and / or vehicle control devices each have a data processing program for controlling and / or regulating the associated vehicle control system and / or vehicle control system of a primary computing unit and / or a secondary computing unit is executed, wherein the at least two vehicle control devices and / or vehicle control devices via a bus connection to a common data bus and / or an internal data connection, via the common data bus and / or the internal data connection, an information exchange of at least two Vehicle control devices and / or vehicle control devices takes place with each other and wherein the loop time t _L at least one data processing program for a number n _1.2 of loops gege over a nominal loop time t _{L, n} is shortened or extended by a time Δt to synchronize the arrival time of information in the vehicle control unit and / or vehicle control unit via the common data bus with an information arrival expectation window of the at least one data processing program, characterized in that the number n _{1,2 is determined} by loops by means of an algorithm as a function of at least one information received via the common data bus and / or the internal data connection. System according to Claim 1, characterized in that the time interval Δt is determined by means of an algorithm as a function of at least one information received via the common data bus. System according to at least one of claims 1 or 2, characterized in that for determining the number n of loops _1,2 and / or for determining the period of time .DELTA.t used, at least one containing a time stamp on the common data received information. System according to claim 3, characterized in that the information with a timestamp additionally comprises further data. System according to at least one of claims 3 or 4, characterized in that information with a timestamp of at least one of the at least two vehicle control devices and / or vehicle control devices via the common data bus to at least one of the at least two vehicle control devices and / or vehicle control devices periodically, in particular zeitäquidistant, to be shipped. System according to at least claims 3 to 5, characterized in that the information with a time stamp from a data bus with its own loop time, in particular a Flexray bus, at least two vehicle control devices and / or vehicle control devices periodically, in particular zeitäquidistant shipped. System according to at least claims 3 to 6, characterized in that the information with a time stamp from an external trigger on the common data bus to at least two vehicle control devices and / or vehicle control devices periodically, in particular zeitäquidistant shipped. System according to at least one of claims 1 to 7, characterized in that the time period .DELTA.t is limited to a limited and / or filtered measure. System according to claim 8, characterized in that the time period .DELTA.t is limited to 1% of the loop time. System according to at least one of claims 1 to 9, characterized in that a vehicle control device specifies a desired value for a vehicle device to be controlled and / or regulated. System according to at least one of claims 1 to 10, characterized in that a vehicle control device reads an actual value from a vehicle device. System according to claim 11, characterized in that a vehicle control device compares the deviation of a desired value for a vehicle device to be controlled and / or regulated with an actual value of the vehicle device to be controlled and / or regulated and adapts the actual value to the desired value. System according to at least one of claims 10 to 12, characterized in that a vehicle device comprises a device from the group: vehicle brake device, motor control device, chassis control device, transmission control device, electric differential device, electric motor control device, optical sensor device and distance sensor device is, which is connected by means of the vehicle control unit and / or vehicle control device to the common data bus. System according to claim 1, characterized in that a vehicle control device and / or vehicle control device having a primary computing unit has a direct bus connection to the common data bus. System according to claim 1, characterized in that a vehicle control device and / or vehicle control device with a secondary computing unit has a separate data connection, in particular a serial peripheral interface or a parallel interface, to a vehicle control device and / or vehicle control device which transmits the information with a time stamp sent and / or received via the common data bus. System according to claim 15, characterized in that the secondary computing unit is a coprocessor which is arranged in the housing of a primary computer unit and is connected to the primary computer via an internal data connection, in particular RAM data exchange, chip timers, interrupts and / or suitable hardware peripherals. System according to at least one of claims 1 to 16, characterized in that the common data bus is a Flexray bus, CAN bus, LIN bus, MOST bus or Ethernet bus. System according to one of claims 1 to 17, characterized in that the information provided with a timestamp of at least two vehicle control devices and / or vehicle control devices is determined and / or formed. Vehicle control unit and / or vehicle control unit, in particular in a motor vehicle, in which a data processing program for controlling and / or regulating a vehicle function is performed by a primary computing unit and / or a secondary computing unit, wherein the vehicle control unit and / or vehicle control unit via a bus connection for a data bus and / or an internal data connection, wherein the vehicle control device and / or vehicle control device exchanges information with at least one further vehicle control device and / or vehicle control device via the data bus and / or the internal data connection and wherein synchronization means the loop time t _{L of} the data processing program for a number n _{1, 2} of loops with respect to a nominal loop time t _{L, n} shorten or extend by a period Δt to the arrival time of information in the vehicle control unit and / or vehicle control unit via the common data bus and / or the int erne data connection with an information arrival expectation window of the data processing program to synchronize, characterized in that an algorithm determines the number n _1,2 of loops in response to at least one information received via the common data bus and / or the internal data connection. Apparatus according to claim 19, characterized in that the apparatus comprises timestamping means which set the time of arrival of information without timestamp as a timestamp. Apparatus according to at least one of claims 19 or 20, characterized in that the device, in particular exclusively, immediately after the receipt of information with a time stamp or the setting of the arrival time of information without timestamp as a time mark in turn sends information. Device according to at least one of claims 19 to 21, characterized in that the vehicle control device and / or vehicle control device sends information with a timestamp on the bus connection for the common data bus. Apparatus according to at least one of claims 19 to 22, characterized in that the nominal loop time t _{L, n of} the data processing program serves as a time base for sending information with timestamps and / or as a time base for setting the timestamp within a sent information with timestamp. Vehicle control unit and / or vehicle control unit, in particular in a motor vehicle, in which a data processing program for controlling and / or regulating a vehicle function is executed by a primary calculation unit and / or a secondary calculation unit, the vehicle control unit and / or vehicle control unit having a bus connection for a common data bus and / or or has an internal data connection, wherein the vehicle control unit and / or vehicle control unit exchanges information with at least one further vehicle control unit and / or vehicle control unit via the common data bus and / or the internal data connection and wherein the vehicle control system and / or vehicle control system information with a time stamp on the bus connection for the common data bus and / or the internal data connection, characterized in that the nominal loop time t _{L, n of} the data processing program as a time base for sending Informat ion with timestamps and / or as a time base for setting the timestamp within a sent information with timestamp serves. Synchronization method for operating a network interconnection system for vehicle control devices and / or for vehicle control devices, in particular in a motor vehicle, comprising at least two vehicle control devices and / or vehicle control devices, wherein in the at least two vehicle control devices and / or vehicle control devices each have a data processing program for controlling and / or regulating the associated vehicle control system and / at least two vehicle control devices and / or vehicle control devices have a bus connection to a common data bus and / or an internal data connection, wherein via the common data bus or the internal data connection, an information exchange of at least two of the at least two vehicle control devices and / or vehicle control devices takes place among each other and wherein the loop time t _{L of} a Datenverarbeitu ngsprogramms least one vehicle control device and / or vehicle control device for a number n _1,2 of loops with respect to a nominal loop time t _{L, n} shortened or extended by a period .DELTA.t to the arrival time of information in the vehicle control unit and / or vehicle control unit via the common Synchronize data bus and / or the internal data connection with an information arrival expectation window of the at least one data processing program, characterized in that determines the number n _1,2 of loops by means of an algorithm in response to at least one information received via the common data bus and / or the internal data connection becomes.

Images