Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
  • B60T8/32—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration
  • B60T8/88—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration with failure responsive means, i.e. means for detecting and indicating faulty operation of the speed responsive control means
  • B60T8/885—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration with failure responsive means, i.e. means for detecting and indicating faulty operation of the speed responsive control means using electrical circuitry
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L12/00—Data switching networks
  • H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
  • H04L12/42—Loop networks
  • H04L12/437—Ring fault isolation or reconfiguration
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T2270/00—Further aspects of brake control systems not otherwise provided for
  • B60T2270/40—Failsafe aspects of brake control systems
  • B60T2270/404—Brake-by-wire or X-by-wire failsafe
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T2270/00—Further aspects of brake control systems not otherwise provided for
  • B60T2270/40—Failsafe aspects of brake control systems
  • B60T2270/413—Plausibility monitoring, cross check, redundancy
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T2270/00—Further aspects of brake control systems not otherwise provided for
  • B60T2270/40—Failsafe aspects of brake control systems
  • B60T2270/414—Power supply failure
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T2270/00—Further aspects of brake control systems not otherwise provided for
  • B60T2270/82—Brake-by-Wire, EHB

Definitions

• the present invention relates to a data processing system for a motor vehicle having a plurality of central control units and a bidirectional ring bus, via which the central control units are set up to communicate with each other.
• a data processing system is for example from
• Data processing systems of this type are considered for safety-related control tasks in motor vehicles, so-called X-by-wire functionalities, since the bidirectional ring bus still allows communication of all control units connected to it, if a segment of the ring bus between two of these units is interrupted.
• a bus segment between the two control units fails , there is always another one on which the units can continue to communicate.
• the present invention provides a data processing system for brake control in a vehicle that provides a high level of safety in case of a simple construction realized.
• This object is achieved by associating with each central control unit a group of wheels of the vehicle whose brake (s) are controllable by the relevant central control unit, and in that each control unit has a dedicated line with at least one brake pedal position Pedal position sensor is connected.
• the control units communicating on the ring bus provide similar control tasks to the wheels of a group in each case, that is to say they can have the same structure or, if appropriate, be programmed essentially the same.
• a failure of such a control unit a priori affects only the braking ability of the wheels it controls, whereas the braking ability of the other wheels is not affected. Even a faulty function of a pedal position sensor or a cable connecting a pedal position sensor to the associated central control unit can only impair the braking ability of a part of the wheels.
• At least one of the central control units is connected to two of the pedal position sensors.
• the relevant control unit can detect the pedal position redundantly and possibly detect an error in the detection. This is particularly expedient if the number of central control units is itself small, in particular not greater than two.
• peripheral control units each associated with a brake on a vehicle wheel, each of which carries out control commands supplied by a central unit.
• peripheral control units associated with the wheels of a group are each arranged to receive and execute control commands relating to their brake from the central control unit associated with the group.
• the central and peripheral control units are expediently also connected via the ring bus.
• Two of the peripheral control units can each be assigned to the same central control unit. These peripheral control units are preferred in each case to wheels of a same axis or diagonally opposite wheels on the vehicle.
• Each peripheral control unit can also be assigned to exactly one of the central control units.
• a single peripheral controller may also be associated with two central controllers; This results in a considerable cost savings.
• a further improvement of the reliability can be achieved if the central control units are supplied by at least two different power supplies.
• Each peripheral control unit is preferably powered by the same power supply as the central control unit to which it is associated in order to minimize the risk of interruption of the command chain between the central control unit and braking due to a power failure.
• the ring bus is preferably reconfigurable, that is, in adjacent to an interruption control units of the ring bus data transfer paths are switched to and from the adjacent control units on detection of the interruption, so that the ring structure is maintained. This ensures that data output by a control unit to the ring bus in only one direction can reach any other control unit on the bus even in the event of a bus segment interruption.
• Figs. 1 to 10 respectively show various embodiments of electronic braking systems according to the present invention.
• central control units connected by a ring bus 8 are denoted by 1, 2-1, 2-2, 2-3, 2-4.
• Each of the central control units 2-1 to 2-4 is connected via a line 6 independent of the ring bus 8 to one of four pedal position sensors 5 arranged on a brake pedal 7. Based on the pedal position measured by the respectively assigned sensor 5, each control unit calculates
• a brake pressure setpoint and transmits it to a peripheral control unit 3-1, 3-2, 3-3 and 3-4, which adjusts this pressure to a brake 9 of the relevant control unit associated wheel 10 .
• the connection of the central control units 2-1 to 2-4 via the ring bus 8 allows these, for example, detected values of the pedal position or calculated values of the
• the control unit 1 which is not absolutely necessary and is not assigned to any peripheral control unit, may in particular be an ESP (Electronic Stability Program) unit known per se, the measurement data determined by sensors of the peripheral control units 3-1 to 3-4, which are for example As the rotation speed or delay of the individual wheels 10 concern, receives via the ring bus 8, evaluates, and if necessary sends correction instructions for adjusting the brake pressure to the central control units 2-1 to 2-4.
• ESP Electronic Stability Program
• Control units 3-1, 3-3 are fed by the same power supply 4-1, while the central control units 2-2, 2-4 and the peripheral control units 3-2, 3-4 connected to them are powered by a second power supply 4-2 are. If one of these power supplies is disturbed, then either only the control units 2-1, 2-3, 3-1, 3-3 or the control units fall. 2-2, 2-4, 3-2, 3-4.
• a potential separation device 14 for. B. in the form of an optocoupler or a capacitive coupling, is provided, the elimination of a power supply can not pull on the ring bus 8 other, powered by the other supply voltage units affected.
• the central control units 2-1 to 2-4 are on the ring bus 8 each over
• Interfaces 16 connected which automatically decouple from the ring bus 8 in case of failure of the supply voltage of the associated central control unit and connect the meeting at the interface 16 segments of the ring bus 8 together. Examples of such interfaces are described in detail in German Patent Application No. 10 2006 006 435.6 with reference to FIGS. 2 to 5.
• the ring structure and the bidirectionality of the ring bus 8 are thus retained, so that the control units remaining in operation can continue to communicate with one another without restriction.
• the ESP unit 1 may be designed to, in such a case, lack one of the other central ones
• the failure of a single peripheral control unit may be detected by the associated central control unit 2-1 and reported to the ESP unit 1 or the other central control units 2-2 to 2-4 in order to control them to be taken into account in the control of the other peripheral control units 3-2 to 3-4.
• the braking capability is maintained on one side of the vehicle.
• FIG. 2 shows a second embodiment of the brake control system according to the invention, which differs from the embodiment shown in FIG. be different from two other power supplies 4-3, 4-4, each supplying the control units 2-3, 3-3 and 2-4, 3-4 of the rear wheels 10.
• the failure of a power supply leads here to the loss of braking ability at maximum one wheel 10; otherwise, the disturbance immunity is substantially the same as in the embodiment of FIG. 1.
• FIG. 3 shows an embodiment of the brake control device according to the invention, in which the number of central control units is reduced to two, labeled 2-1 and 2-2, respectively.
• Each of these central control units 2-1, 2-2 is connected to two pedal position sensors 5 on the brake pedal 7 via two lines 6, d. H. the pedal position sensing is redundant at each of the two central control units 2-1, 2-2.
• a fault of one of the sensors 5 or the line 6 connecting it to the associated central control unit 2-1 or 2-2 is detected on the part of this central control unit by comparison with the detection result of the respective other sensor 5. Since the comparison alone in the
• the central control unit makes a decision on this by comparison with measured values of the pedal position communicated via the bus 8 by the respective other central control unit.
• the central control unit affected by the sensor disturbance can identify the faulty sensor and continue to work with the respective undisturbed one.
• Each central control unit 2-1, 2-2 respectively drives a group of two peripheral control units 3-1, 3-3 and 3-2, 3-4 belonging to respective diagonally opposite wheels 10.
• the ring bus 8 is guided so that exactly one bus segment lies between each central control unit 2-1, 2-2 and the peripheral control units 3-1, 3-3 or 3-2, 3-4 controlled by it.
• the associated control units 2-1, 3-1, 3-3 and 2-2, 3-2, 3-4 are respectively fed by the same power supply 4-1 and 4-2.
• Fig. 4 differs from that of Fig. 3 by the addition of another central control unit 2-3, which is inserted between the peripheral control units 3-1, 3-4 of the front wheels in the ring bus 8.
• the central control unit 4-1 is powered by the same power supply 4-1 as the central control unit 2-1;
• Each of these two control units is assigned a respective sensor 5 on the brake pedal 7, whereas the control unit 2-2 is connected to two sensors 5 as in FIG. If one power supply 4-1 or 4-2 fails, two of the sensors 5 thus remain connected to operational control units.
• the central control unit 2-3 performs the control tasks of the units 2-1, 2- 2 respectively redundantly for the peripheral control units 3-1, 3-4 of the front wheels 10.
• the complete front axle is able to brake.
• a failure of the unit 2-3 has no effect on the functioning of the system.
• FIG. 5 differs from that of FIG. 4 in that the central control unit 2-3 is connected to both power supplies 4-1, 4-2 and a group of redundant peripheral control units 3-5, 3 -6 on the two front wheels 10 drives.
• the power supplies 4-1, 4-2 are connected to a common supply terminal of the unit 2-3 Decoupling elements 20 such as diodes or switches connected.
• Each power supply 4-1 and 4-2 feeds one of the two peripheral control units 3-1, 3-5 and 3-4, 3-6 on the two front wheels, respectively.
• the number of pedal position sensors 5 is reduced to three, and each of these
• Sensors 5 are connected to one of the central control units 2-1 to 2-3. Since two central control units remain functional in the event of a power failure, the sensors 5, despite their reduced number, remain redundant in the event of a supply failure.
• FIG. 6 shows a simplified modification of FIG. 5, in which, as in the embodiment of FIG. 4, the central control units 2-1, 2-3 each have the peripheral control unit 3-1 of the right front wheel and the central control units 2- 2, 2-3 address the peripheral control unit 3-4 of the left front wheel. In order to improve the reliability of the peripheral control units 3-1, 3-4, these are fed as well as the central control unit 2-3 itself by both power supplies 4-1, 4-2 via decoupling elements 20.
• Fig. 7 differs from the previously described by a third power supply 4-3, which feeds the central control unit 2-3 and connected to it peripheral control units 3-5, 3-6 on the two front wheels.
• a third power supply 4-3 which feeds the central control unit 2-3 and connected to it peripheral control units 3-5, 3-6 on the two front wheels.
• two of the power supplies 4-1, 4-2, 4-3 fail; depending on which it is, either the braking ability of the front axle or diagonally opposite wheels is retained.
• the central control units 2-1, 2-3 jointly control the peripheral control unit 3-1 and the central control units 2-2, 2-3 the peripheral control unit 3-4, and the peripheral control units 3-1, 3-4 are fed by the two mutually decoupled power supplies 4-1, 4-3 and 4-2, 4-3. Even if failing by a short circuit in one of the two common-powered peripheral control units 3-1, 3-4 both connected power supplies, remains one of the three power supplies, either 4-1 or 4-2, spared, so that the braking effect on a diagonal remains.
• the embodiment of FIG. 9 differs from that of FIG.
• each redundant peripheral control unit 3-7, 3-8 is connected to the same power supply 4-3 and 4-2, respectively.
• a power supply, a central control unit, a peripheral control unit, a segment of the ring bus 8 or a sensor 5 can fail without affecting the braking capability. In case of failure of two power supplies, the braking capacity is maintained at least on a diagonal. The effects of a failure of two segments of the ring bus 8 are different depending on the position of the segments; even in the most unfavorable case, however, the braking capacity on the front axle remains intact.
• peripheral control units 3-1 to 3-4 are provided on each wheel 10 instead of the peripheral control units doubly provided on each wheel 10, of which, however, each is provided by two different power supplies 4
• a short circuit in a peripheral Control unit can affect a maximum of two power supplies; the remaining power supply ensures the braking capability of either the front axle or a diagonal.
• each central control unit not only supplies control commands to its associated peripheral control units, which are generally connected to the same power supply as the central control unit, but that all central control units have concurrent commands for all peripheral control units send on the bus 8.
• a peripheral control unit can instead resort to the redundant commands of another control unit.
• a peripheral control unit can also recognize which command is sent by the majority of the central control units by comparing commands sent to them from the various central control units will ignore a command sent by a minority.
• Errors that occur and are detected in the brake system are expediently displayed to the driver so that he can initiate the repair.
• a circuit that receives error messages from the system and converts them into warnings for the driver can be inserted as another unit at any point in the ring bus 8; it may also be individually connected to each of the central and peripheral units via dedicated lines independent of bus 8.
• Data circulates on the bus 8 in a fixed time frame, in which each control unit is assigned a regularly recurring time slot.
• Control units and their interfaces 16 support several different operating states, a normal mode in which, on the one hand, each unit receives data not intended for it over a first bus segment and forwards it on a different bus segment with a small delay of two to three clock cycles and data in a transmission time slot assigned to it sends, one
• Bypass mode in which, if for some reason the unit is not active, the interface forwards all data arriving via the first bus segment to the second bus segment (possibly simulating the delay caused by the control unit in normal mode), and NEN bypass mode, in which the interface, if over a the bus segments connected to them receive no or physically faulty signals, data arriving on a first line of the other segment are sent back on a second line of this other segment.
• NEN bypass mode in which the interface, if over a the bus segments connected to them receive no or physically faulty signals, data arriving on a first line of the other segment are sent back on a second line of this other segment.

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• Engineering & Computer Science (AREA)
• Computer Networks & Wireless Communication (AREA)
• Signal Processing (AREA)
• Transportation (AREA)
• Mechanical Engineering (AREA)
• Regulating Braking Force (AREA)
• Valves And Accessory Devices For Braking Systems (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

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Citations (6)

Family Cites Families (4)

• 2006
  • 2006-12-19 DE DE200610059919 patent/DE102006059919A1/de not_active Withdrawn
• 2007
  • 2007-12-06 WO PCT/EP2007/063453 patent/WO2008074649A1/de active Application Filing
  • 2007-12-06 JP JP2009526133A patent/JP2010501411A/ja active Pending
  • 2007-12-06 EP EP07847925A patent/EP2114741A1/de not_active Ceased

Patent Citations (6)

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