Brake architecture for combined hydraulic and electromechanical brake system

Abstract

The present disclosure provides a brake architecture for a combined hydraulic and electromechanical brake system. The brake system includes a first hydraulic brake assembly associated with a first front wheel; a second hydraulic brake assembly associated with a second front wheel; a front EBB module operably coupled to the first hydraulic brake assembly and the second hydraulic brake assembly for primary operation of the first hydraulic brake assembly and the second hydraulic brake assembly; a first EMB assembly associated with the first rear wheel; a second EMB assembly associated with a second rear wheel; a controller operably coupled to the first EMB assembly and the second EMB assembly for primary operation of the first EMB assembly and the second EMB assembly; first and second power networks providing redundant power supply to the system; and a bus network operably coupling both the EBB module and the controller to the first EMB assembly and the second EMB assembly such that the EBB module can provide control of standby operation of the first EMB assembly and the second EMB assembly if the controller is inoperable.

Description

Technical Field

[0001] Exemplary embodiments relate generally to vehicle braking systems and, more particularly, to a system that provides redundant power to different types of brake assemblies. Background Art

[0002] Brake assist systems are commonly used in automotive settings to increase the actuation force from the driver's foot on the brake pedal to an acceptable level in order to properly engage the vehicle's brakes when hydraulic brakes are employed. At the same time, electromechanical brakes (EMBs) are also becoming increasingly popular, most often as an alternative to hydraulic brakes. Insofar as a combination of hydraulic brakes and EMBs are employed on the same vehicle, issues may arise regarding complicating the provision of redundant power supplies and signaling for activating each of the different brake system types.

[0003] Therefore, it may be desirable to develop an architecture that provides redundant power supply and signaling capabilities with respect to different types of braking systems. Summary of the invention

[0004] According to an exemplary embodiment, a vehicle cooling system may be provided. The system may include a first hydraulic brake assembly associated with a first front wheel; a second hydraulic brake assembly associated with a second front wheel; a front electronic brake booster (EBB) module operably coupled to the first hydraulic brake assembly and the second hydraulic brake assembly to control primary operations of the first hydraulic brake assembly and the second hydraulic brake assembly; a first electromechanical brake (EMB) assembly associated with a first rear wheel; a second EMB assembly associated with a second rear wheel; a controller operably coupled to the first EMB assembly and the second EMB assembly to control primary operations of the first EMB assembly and the second EMB assembly; a first power network and a second power network, the first power network and the second power network providing a redundant power supply to the system; and a communication bus network operably coupling both the EBB module and the controller to the first EMB assembly and the second EMB assembly so that the EBB module can provide control of backup operations of the first EMB assembly and the second EMB assembly in the event that the controller is inoperable.

[0005] In another exemplary embodiment, a communication bus network for a vehicle brake system may be provided. The vehicle brake system includes a first hydraulic brake assembly associated with a first front wheel; a second hydraulic brake assembly associated with a second front wheel; a front EBB module, the front EBB module operably coupled to the first hydraulic brake assembly and the second hydraulic brake assembly to control the primary operation of the first hydraulic brake assembly and the second hydraulic brake assembly; a first EMB assembly associated with a first rear wheel; a second EMB assembly associated with a second rear wheel; a controller operably coupled to the first EMB assembly and the second EMB assembly to control the primary operation of the first EMB assembly and the second EMB assembly; and a first power network and a second power network, the first power network and the second power network providing redundant power supply to the system. The communication bus network may include: a first communication bus, the first communication bus operably coupling the first EMB assembly and the second EMB assembly to the EBB module; and a second bus network, the second bus network operably coupling the first EMB assembly and the second EMB assembly to the controller. The communication bus network operably couples both the EBB module and the controller to the first and second EMB assemblies to enable the EBB module to provide control of backup operation of the first and second EMB assemblies in the event that the controller is inoperable. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Having thus generally described the invention, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and in which:

[0007] Figure 1 A block diagram of a vehicle control system according to an exemplary embodiment is shown;

[0008] Figure 2 According to an exemplary embodiment, Figure 1 A block diagram of some components of a vehicle control system;

[0009] Figure 3 A block diagram illustrating signaling arbitrated by an EBB module associated with brake control according to an exemplary embodiment; and

[0010] Figure 4 A block diagram of a gateway that manages signals between communication buses is shown according to an exemplary embodiment. DETAILED DESCRIPTION

[0011] Some exemplary embodiments will now be described more fully below with reference to the accompanying drawings, in which some but not all exemplary embodiments are shown. In fact, the examples described and depicted herein should not be construed as limiting the scope, applicability or configuration of the present disclosure. Rather, these exemplary embodiments are provided so that the present disclosure will meet applicable requirements. The same reference numerals always refer to the same elements. In addition, as used herein, the term "or" will be interpreted as a logical operator whose result is true whenever one or more of its operands are true. As used herein, an operable connection should be understood to involve a direct or indirect connection, in which case the connection can achieve functional interconnection of components that are operably connected to each other.

[0012] Typically, the redundancy of a pure hydraulic brake system is provided by a mechanical hydraulic push process of the brake pedal on a hydraulic cylinder, which supplies brake pressure to all four wheel ends. In some cases and vehicle architectures, the rear brake circuit is isolated from the front brake circuit during the mechanical hydraulic push process, where the rear electric parking brake is used to transmit additional braking torque. The front electronic brake booster (EBB) hydraulic, rear axle electromechanical brake (EMB) architecture in a passenger vehicle requires redundant power supply and supporting control structure. However, as described above, this may be difficult to achieve in the context of adopting different brake systems, and signaling in a backup operating mode may also be difficult to achieve. An exemplary embodiment is intended to provide a separate electronic control unit (ECU) for each of the rear EMBs, each of which is powered from a different power supply, but wherein signaling can be provided via an EBB module in a backup mode (i.e., when the central controller for the ECU is unavailable) using a network bus architecture that provides backup signaling when needed.

[0013] Figure 1 A block diagram of an exemplary embodiment of a vehicle control system 100 is shown. Components of the control system 100 may be incorporated into a vehicle 110 (e.g., via an operative connection to a chassis of the vehicle 110, various components of the vehicle 110, and / or an electronic control system of the vehicle 110). It is worth noting that although Figure 1 The components of the control system 100 may be operably coupled to the vehicle 110, but it should be understood that such connection may be direct or indirect. In addition, some of the components of the control system 100 may be connected to the vehicle 110 via intermediate connections to other components of the chassis or other electronic and / or mechanical systems or components.

[0014] The control system 100 may include one or more input devices in the form of one or more control pedals. In some embodiments, the control pedals may include a brake pedal 120, which is typically foot-operated by an operator 125 to initiate the application of a braking force or braking torque at the wheels of the vehicle 110. The brake pedal 120 may be operably coupled to a hydraulic brake 130 (e.g., a front brake) via a mechanical and / or hydraulic connection under the control of an EBB module 135. The brake pedal 120 may also be operably coupled to an EMB 140 (e.g., a rear brake) via a brake pedal position sensor 142, and the EMB 140 may be actuated in response to operation of a corresponding instance of an ECU 144 receiving instructions from a vehicle control module (VCM) 146, which may be operably coupled to the brake pedal position sensor 142 to receive position information indicative of the brake pedal 120. The brake pedal position sensor 142 may provide data indicative of the precise position of the brake pedal 120 as an input to the VCM 146.

[0015] It is noted that the control pedal may alternatively be manually operated or any other operable member via which the operator 125 may provide input indicative of the operator's intent with respect to controlling the net torque applied to the wheels of the vehicle 110. In some cases, the control system 100 may be configured to perform other tasks related or unrelated to propulsion and braking control or performance management.

[0016] In an exemplary embodiment, the control system 100 may receive information for determining a vehicle state from various components or subassemblies 150 of the vehicle 110. Additionally or alternatively, various sensors that may be operably coupled to the components or subassemblies 150 may be included and may provide input to the control system 100 for determining a vehicle state. Such sensors may be part of a sensor network 160, and the sensors of the sensor network 160 may be operably coupled to the control system 100 (and / or the components or subassemblies 150) via one or more instances of a vehicle communication bus (e.g., a controller area network (CAN) bus) 170.

[0017] The components or subassemblies 150 may include, for example, a braking system, a propulsion system, and / or a wheel assembly of the vehicle 110. The braking system may be configured to provide braking inputs to the braking components of the vehicle 110 and include the components discussed above. One or more corresponding sensors of the sensor network 160 that may be operably coupled to the braking system and / or the wheel assembly may provide information related to braking torque, braking torque rate, vehicle speed (including the rate of change of speed), front / rear wheel speed, vehicle pitch, etc. Inputs from the sensors of the sensor network 160 may be provided to the control system 100 so that the control system 100 can provide various primary and secondary (or backup) control functions related to the components or subassemblies 150. Thus, for example, the control system 100 may be able to receive numerous different parameters, indications, and other information that may relate to or indicate different situations or conditions associated with the vehicle state. The control system 100 may also receive information indicating the operator 125's intention to control various aspects of the operation of the vehicle 110, and then be configured to use the received information to provide instructions to control the response to the determined situation or condition. Figure 1 The control system 100 may be similar in many respects to conventional systems, except that the control system 100 may be modified to respond to situations where the EMB 140 requires backup power and signaling, as described in reference to Figures 2 to 4 Described in more detail.

[0018] Figure 2 A block diagram showing various components of a control system 200, which may be considered to be Figure 1 A specific example of a control system 100, or a portion thereof associated with a vehicle braking system. In this regard, for example, Figure 2 Shows Figure 1 0048 00490 ...

[0019] The control system 200 may include a brake pedal 120 , which may have a corresponding brake pedal position sensor 142 for determining a position of the brake pedal 120 and providing a signal or input indicative of the determined position to the VCM 146 . Figure 1The hydraulic brakes 130 of the vehicle 110 may include a first hydraulic brake assembly 210 associated with one of the wheels 212 of the vehicle 110 (e.g., the left front wheel), and a second hydraulic brake assembly 220 associated with another of the wheels 212 of the vehicle 110 (e.g., the right front wheel). Each of the first hydraulic brake assembly 210 and the second hydraulic brake assembly 220 may include a respective instance of a brake caliper or drum for providing friction braking of the corresponding wheel 212 associated therewith. Hydraulic power for actuating the first hydraulic brake assembly 210 and the second hydraulic brake assembly 220 may be provided from the EBB module 135 via respective instances of hydraulic lines 222. Each of the wheels 212 associated with the first hydraulic brake assembly 210 and the second hydraulic brake assembly 220 may also have a corresponding wheel speed sensor (e.g., a first front wheel speed sensor (FFWSS) 224 and a second front wheel speed sensor (SFWSS) 226) associated therewith to measure the wheel speed of the corresponding wheel of the wheels 212 and provide information about the measured wheel speed to the EBB module 135.

[0020] The control system 200 may also include a first EMB 240 associated with a corresponding one of the wheels 212 (e.g., the left rear wheel) and a second EMB 242 associated with another corresponding one of the wheels 212 (e.g., the right rear wheel). The first EMB 240 and the second EMB 242 are Figure 1 Examples of EMB 140, and Figure 1 The ECU 144 may be composed of Figure 2 1 and 2. The first ECU 250 and the second ECU 252 are exemplified. The first ECU 250 may be operably coupled to a first motor 260, which may actuate a brake caliper or drum (based on application of the brake pedal 120) to provide braking torque to a wheel 212 (e.g., a left rear wheel) under the control of the first ECU 250. The second ECU 252 may be operably coupled to a second motor 262, which may actuate a brake caliper or drum (based on application of the brake pedal 120) to provide braking torque to a wheel 212 (e.g., a right rear wheel) under the control of the second ECU 252.

[0021] The wheel speed of the wheel 212 (e.g., the left rear wheel) corresponding to the first EMB 240 may be measured by a first wheel speed sensor (WSS) 270, and the wheel speed of the wheel 212 (e.g., the right rear wheel) corresponding to the second EMB 242 may be measured by a second WSS 272. The first WSS 270 may provide an indication of the wheel speed measured for its corresponding wheel 212 (e.g., the left rear wheel) to the first ECU 250, and the second WSS 272 may provide an indication of the wheel speed measured for its corresponding wheel 212 (e.g., the right rear wheel) to the second ECU 252.

[0022] The first ECU 250 and the second ECU 252 obtain electronic instructions for initiating the braking function from the VCM 146 via the first EMB 240 and the second EMB 242, respectively, and therefore in this example there is no mechanical / hydraulic connection between the brake pedal 120 and the rear brake (while such a connection exists in the front brake). Given that these instructions are transmitted electronically, redundant power supplies are employed to ensure that braking can be achieved even if one of the power supplies happens to be lost for any reason. Therefore, a first power network 280 is provided to power the first EMB 240, the first ECU 250 and the first motor 260. A second power network 282 is provided to power the second EMB 242, the second ECU 252 and the second motor 262. In this example, the first power network 280 also powers the VCM 146, and the second power network 282 also powers the EBB module 135. Therefore, all electronic components required for braking are powered by different power supplies and corresponding networks to ensure that power is available for braking. However, signaling to ensure that the powered components receive the signaling required to implement the desired or required braking may be another matter entirely. In an exemplary embodiment, the first power network 280 may be a quality managed (QM) power source, and the second power network 282 may be an ISILB power source. However, other power sources may be employed in alternative embodiments.

[0023] The first ECU 250 and the second ECU 252 may each be operably coupled to the VCM 146 to receive control instructions therefrom via a first communication bus 290 (e.g., a common CAN). As discussed above, the VCM 146 is the primary control source for providing control signals to the first ECU 250 and the second ECU 252. However, if the VCM 146 is lost or inoperable for any reason (e.g., loss of the first power network 280, loss of communications to / from the VCM 146, etc.), backup signaling for the first ECU 250 and the second ECU 252 may be provided via a communication bus network that incorporates the EBB module 135 as a backup control signal source. To achieve this, the communication bus network may incorporate a second communication bus 292 (e.g., a dedicated CAN) that couples the first ECU 250 and the second ECU 252 to the EBB module 135. However, in some cases, the second communication bus 292 may also be divided into two separate dedicated CAN buses. By employing the first communication bus 290 and the second communication bus 292, for example, if the VCM 146 is inoperable for any reason and the primary signaling for controlling the braking function at the first ECU 250 and the second ECU 252 is therefore interrupted or unavailable, backup signaling regarding the braking function can be provided from the EBB module 135 to the first ECU 250 and the second ECU 252 via the second communication bus 292.

[0024] Thus, for example, if a braking torque request of 1000 Nm is otherwise generated at the VCM 146 (based on the position of the brake pedal 120), instructions will typically be provided from the VCM 146 to the first ECU 250 and the second ECU 252 via the first communication bus 290, wherein the first EMB 240 is commanded to apply a braking torque of 500 Nm and the second EMB 242 is commanded to apply a braking torque of 500 Nm. The loss of the VCM 146 and / or the first communication bus 290 will then be responded to by providing corresponding instructions from the EBB module 135 to each of the first ECU 250 and the second ECU 252 via the second communication bus 292 to apply corresponding braking torques to the first EMB 240 and the second EMB 242, each of which may also be approximately 500 Nm of braking torque.

[0025] Therefore, an exemplary embodiment provides a central vehicle control module or controller (e.g., VCM 146) for primary brake control, with EBB modules as a secondary control option, where each module or controller is powered from a different power source. The backup function of the second communication bus 292 can ensure that redundant signaling and redundant power supply can be provided to the EMB at the same time. However, in some cases, other functional capabilities can also be provided to enhance conventional systems. For example, in an exemplary embodiment, the first EMB 240 and the second EMB 242 can also provide wheel-end anti-lock braking (ABS) functionality in response to the loss of any one or both of the wheel speed sensors (e.g., the first WSS270 and / or the second WSS272). In some cases, the final parking brake application can also be completed due to the loss of communication. In this regard, for example, if a loss of communication with both the VCM 146 and the EBB module 135 is experienced, the first ECU 250 and the second ECU 252 may be programmed to apply the parking brake once the measured wheel speeds (e.g., from the first WSS 270 and the second WSS 272) decrease (and possibly also stabilize) to zero speed.

[0026] In some embodiments, the EBB module 135 may perform brake signal arbitration for the system. Figure 3 A block diagram showing signaling associated with operation of a braking system of a vehicle in which such arbitration is practiced is shown according to an exemplary embodiment. In this regard, a pedal force 300 may be applied at the brake pedal 120 and transmitted to the EBB module 135. The EBB module 135 may transmit a brake pedal travel estimate 310 to the VCM 146. The brake pedal travel estimate 320 may drive the generation of a brake torque request from the VCM 146 to the first EMB 240 and the second EMB 242 via arbitration at the EBB module 135. In this regard, the VCM 146 may provide the front axle and rear axle brake torque requests 330 to the EBB module 135. Then, the corresponding hydraulic brake actuation 332 may be provided from the EBB module 135 to the first hydraulic brake assembly 210 and the second hydraulic brake assembly 220, and the arbitrated brake torque request 340 may also be transmitted from the EBB module 135 to the first EMB 240 and the second EMB 242. The VCM 146 may also provide a parking brake command 350 to the EBB module 135 to provide a relay command 352 to the second EMB 242 , while also providing a parking brake command 354 directly to the first EMB 240 .

[0027] Although not in Figure 2, but in some embodiments, the components may be provided as a gateway device to act as a gateway between the various buses (e.g., the first communication bus 290 and the second communication bus 292) of the communication bus network. Although not required, in some cases, the gateway device may be embodied as Figure 4 The high power computer cluster A (HPCCA) 400 is shown. In this regard, Figure 4 The brake pedal 120 is shown providing an input 410 to the EBB module 135 based on the pedal force, which in turn generates a hydraulic brake actuation 420 from the EBB module 135 to the first hydraulic brake assembly 210 and the second hydraulic brake assembly 220. At the same time, movement of the brake pedal 120 also causes the brake pedal position sensor 142 to generate a pedal angle 430 to provide to the VCM 146. The VCM 146 can generate a brake torque request 440 for the rear axle, which can then be split by the HPCCA 400 into separate individual brake torque requests 442 for the first EMB 240 and the second EMB 242. The parking brake request 460 can also be split by the HPCCA 400 into corresponding individual parking brake requests 462 for the first EMB 240 and the second EMB 242.

[0028] Therefore, a vehicle braking system for a vehicle may be provided. The vehicle braking system may include a first hydraulic brake assembly associated with a first front wheel; a second hydraulic brake assembly associated with a second front wheel; a front EBB module operably coupled to the first hydraulic brake assembly and the second hydraulic brake assembly to control primary operations of the first hydraulic brake assembly and the second hydraulic brake assembly; a first EMB assembly associated with a first rear wheel; a second EMB assembly associated with a second rear wheel; a controller operably coupled to the first EMB assembly and the second EMB assembly to control primary operations of the first EMB assembly and the second EMB assembly; a first power network and a second power network, the first power network and the second power network providing a redundant power supply to the system; and a communication bus network operably coupling both the EBB module and the controller to the first EMB assembly and the second EMB assembly so that the EBB module can provide control of backup operations of the first EMB assembly and the second EMB assembly in the event that the controller is inoperable.

[0029] The systems of some embodiments may include additional features, modifications, expansions, etc. to achieve further goals or enhance the performance of the system. The additional features, modifications, expansions, etc. may be added in any combination with each other. The following is a list of various additional features, modifications, and expansions, which may be added individually or in any combination with each other. For example, the first power network is operably coupled to the controller and the first EMB assembly, and the second power network is operably coupled to the EBB module and the second EMB assembly. In an exemplary embodiment, the communication bus network may include: a first bus network, the first bus network operably coupling the first EMB assembly and the second EMB assembly to the EBB module; and a second bus network, the second bus network operably coupling the first EMB assembly and the second EMB assembly to the controller. In some cases, the first bus network may be a dedicated controller area network (CAN) bus, and the second bus network may be a public CAN bus. In an exemplary embodiment, the first power network may be a QM power supply, and the second power network may be an ASIL B power supply. In an exemplary embodiment, the first EMB assembly may include a first electronic control unit (ECU), and the second EMB assembly includes a second ECU, the first bus network may extend between the first ECU and the second ECU and the EBB module, and the second bus network may extend between the first ECU and the second ECU and the controller. In an exemplary embodiment, the first ECU and the second ECU may be operably coupled to a first wheel speed sensor and a second wheel speed sensor, respectively, wherein the first wheel speed sensor provides the wheel speed for the first rear wheel to the first ECU, and the second wheel speed sensor provides the wheel speed for the second rear wheel to the second ECU. In response to a loss of communication between the first ECU and the second ECU and both the controller and the EBB module, when the first wheel speed sensor and the second wheel speed sensor each indicate zero wheel speed for the first rear wheel and the second rear wheel, the first ECU and the second ECU may apply parking brakes to the first rear wheel and the second rear wheel, respectively. In some cases, the first ECU and the second ECU may provide wheel-end anti-lock braking system (ABS) functions for the first rear wheel and the second rear wheel, respectively, in response to a loss of communication from the first wheel speed sensor and the second wheel speed sensor.In an exemplary embodiment, the first ECU and the second ECU may each include a corresponding motor to provide braking torque to the first rear wheel and the second rear wheel, respectively, and signaling for operation of the corresponding motors of the first ECU and the second ECU is provided primarily via the controller through the second bus network, and in a backup case via the EBB module. In some cases, a brake pedal of the system may be operably coupled to the controller, and a signaling for braking from the EBB module is received by the controller from the brake pedal.

[0030] A person skilled in the art of the invention to which the present invention belongs who has benefited from the teachings presented in the foregoing description and the associated drawings will think of many modifications and other embodiments of the invention set forth herein. Therefore, it should be understood that the present invention is not limited to the specific embodiments disclosed, and modifications and other embodiments are intended to be included within the scope of the appended claims. In addition, although the foregoing description and the associated drawings describe exemplary embodiments in the context of certain exemplary combinations of elements and / or functions, it should be understood that alternative embodiments may provide different combinations of elements and / or functions without departing from the scope of the appended claims. In this regard, for example, as may be set forth in some of the appended claims, combinations of elements and / or functions different from those explicitly described above are also contemplated. Where advantages, benefits, or solutions to problems are described herein, it should be understood that such advantages, benefits, and / or solutions may be applicable to some exemplary embodiments, but not necessarily to all exemplary embodiments. Therefore, any advantages, benefits, or solutions described herein should not be considered to be critical, necessary, or essential to all embodiments or embodiments claimed herein. Although specific terms are employed herein, they are used only in a general and descriptive sense, not for the purpose of limitation.

[0031] According to the present invention, a vehicle braking system is provided, which has: a first hydraulic brake assembly associated with a first front wheel; a second hydraulic brake assembly associated with a second front wheel; a front electronic brake booster (EBB) module, the front electronic brake booster (EBB) module is operably connected to the first hydraulic brake assembly and the second hydraulic brake assembly to control the main operation of the first hydraulic brake assembly and the second hydraulic brake assembly; a first electromechanical brake (EMB) assembly associated with a first rear wheel; a second EMB assembly associated with a second rear wheel; a controller, the controller is operably connected to the first EMB assembly and the second EMB assembly to control the main operation of the first EMB assembly and the second EMB assembly; a first power network and a second power network, the first power network and the second power network provide redundant power supply to the system; and a communication bus network, the communication bus network operably connects both the EBB module and the controller to the first EMB assembly and the second EMB assembly so that the EBB module can provide control of backup operation of the first EMB assembly and the second EMB assembly when the controller is inoperable.

[0032] According to an embodiment, the first power network is operably coupled to the controller and the first EMB assembly, and the second power network is operably coupled to the EBB module and the second EMB assembly.

[0033] According to an embodiment, the communication bus network includes: a first bus network operably coupling the first EMB assembly and the second EMB assembly to the EBB module; and a second bus network operably coupling the first EMB assembly and the second EMB assembly to the controller.

[0034] According to an embodiment, the first bus network is a dedicated Controller Area Network (CAN) bus and the second bus network is a public CAN bus.

[0035] According to an embodiment, the first power network is QM power and the second power network is ASIL B power.

[0036] According to an embodiment, the first EMB assembly includes a first electronic control unit (ECU), and the second EMB assembly includes a second ECU, the first bus network extends between the first ECU and the second ECU and the EBB module, and wherein the second bus network extends between the first ECU and the second ECU and the controller.

[0037] According to an embodiment, the first ECU and the second ECU are operably coupled to a first wheel speed sensor and a second wheel speed sensor, respectively, the first wheel speed sensor providing the wheel speed for the first rear wheel to the first ECU, and the second wheel speed sensor providing the wheel speed for the second rear wheel to the second ECU, and wherein in response to a loss of communication between the first ECU and the second ECU and both the controller and the EBB module, the first ECU and the second ECU apply parking brakes to the first rear wheel and the second rear wheel, respectively, when the first wheel speed sensor and the second wheel speed sensor each indicate zero wheel speed for the first rear wheel and the second rear wheel.

[0038] According to an embodiment, the first ECU and the second ECU provide wheel end anti-lock braking system (ABS) functionality for the first rear wheel and the second rear wheel, respectively, in response to a loss of communication from the first wheel speed sensor and the second wheel speed sensor.

[0039] According to an embodiment, the first ECU and the second ECU each include a corresponding motor to provide braking torque to the first rear wheel and the second rear wheel respectively, and wherein signaling for operation of the corresponding motors of the first ECU and the second ECU is primarily provided via the controller through the second bus network, and in a backup case via the EBB module.

[0040] According to an embodiment, a brake pedal of the system is operatively coupled to a controller, and a signaling for braking from the EBB module is received by the controller from the brake pedal.

[0041] According to the present invention, a communication bus network for a vehicle brake system is provided, which has: a first hydraulic brake assembly associated with a first front wheel; a second hydraulic brake assembly associated with a second front wheel; a front electronic brake booster (EBB) module, the front electronic brake booster (EBB) module being operably connected to the first hydraulic brake assembly and the second hydraulic brake assembly to control the main operations of the first hydraulic brake assembly and the second hydraulic brake assembly; a first electromechanical brake (EMB) assembly associated with a first rear wheel; a second EMB assembly associated with a second rear wheel; a controller, the controller being operably connected to the first EMB assembly and the second EMB assembly to control the main operations of the first EMB assembly and the second EMB assembly; and a first an electric power network and a second electric power network, wherein the first electric power network and the second electric power network provide redundant power supply to the system, and the communication bus network includes: a first communication bus, wherein the first communication bus operably connects the first EMB assembly and the second EMB assembly to the EBB module; and a second bus network, wherein the second bus network operably connects the first EMB assembly and the second EMB assembly to the controller, wherein the communication bus network operably connects both the EBB module and the controller to the first EMB assembly and the second EMB assembly so that the EBB module can provide control of backup operation of the first EMB assembly and the second EMB assembly in the event that the controller is inoperable.

[0042] According to an embodiment, the first power network is operably coupled to the controller and the first EMB assembly, and the second power network is operably coupled to the EBB module and the second EMB assembly.

[0043] According to an embodiment, the first bus network is a dedicated Controller Area Network (CAN) bus and the second bus network is a public CAN bus.

[0044] According to an embodiment, the first power network is QM power and the second power network is ASIL B power.

[0045] According to an embodiment, the first EMB assembly includes a first electronic control unit (ECU), and the second EMB assembly includes a second ECU, the first bus network extends between the first ECU and the second ECU and the EBB module, and wherein the second bus network extends between the first ECU and the second ECU and the controller.

[0046] According to an embodiment, the first ECU and the second ECU are operably coupled to a first wheel speed sensor and a second wheel speed sensor, respectively, the first wheel speed sensor providing the wheel speed for the first rear wheel to the first ECU, and the second wheel speed sensor providing the wheel speed for the second rear wheel to the second ECU, and wherein in response to a loss of communication between the first ECU and the second ECU and both the controller and the EBB module, the first ECU and the second ECU apply parking brakes to the first rear wheel and the second rear wheel, respectively, when the first wheel speed sensor and the second wheel speed sensor each indicate zero wheel speed for the first rear wheel and the second rear wheel.

[0047] According to an embodiment, the first ECU and the second ECU provide wheel end anti-lock braking system (ABS) functionality for the first rear wheel and the second rear wheel, respectively, in response to a loss of communication from the first wheel speed sensor and the second wheel speed sensor.

[0048] According to an embodiment, the first ECU and the second ECU each include a corresponding motor to provide braking torque to the first rear wheel and the second rear wheel respectively, and wherein signaling for operation of the corresponding motors of the first ECU and the second ECU is primarily provided via the controller through the second bus network, and in a backup case via the EBB module.

[0049] According to an embodiment, a brake pedal of the system is operatively coupled to a controller, and a signaling for braking from the EBB module is received by the controller from the brake pedal.

Claims

1. A communication bus network for a vehicle brake system, comprising a first hydraulic brake assembly associated with a first front wheel; a second hydraulic brake assembly associated with a second front wheel; a front electronic brake booster (EBB) module, the front electronic brake booster (EBB) module being operably coupled to the first hydraulic brake assembly and the second hydraulic brake assembly to control primary operations of the first hydraulic brake assembly and the second hydraulic brake assembly; a first electromechanical brake (EMB) assembly associated with a first rear wheel; a second EMB assembly associated with a second rear wheel; a controller, the controller being operably coupled to the first EMB assembly and the second EMB assembly to control primary operations of the first EMB assembly and the second EMB assembly; and a first power network and a second power network, wherein the first power network and the second power network provide redundant power supply to the system, and the communication bus network comprises: a first bus network operatively coupling the first EMB assembly and the second EMB assembly to the EBB module; as well as a second bus network operatively coupling the first EMB assembly and the second EMB assembly to the controller, Wherein the communication bus network operably couples both the EBB module and the controller to the first and second EMB assemblies to enable the EBB module to provide control of backup operation of the first and second EMB assemblies in the event that the controller is inoperable.

2. The communication bus network of claim 1, wherein the first power network is operably coupled to the controller and the first EMB assembly, and the second power network is operably coupled to the EBB module and the second EMB assembly.

3. The communication bus network of claim 2, wherein the first bus network is a dedicated controller area network (CAN) bus and the second bus network is a public CAN bus. 4 . The communication bus network of claim 3 , wherein the first power network is QM power and the second power network is ASIL B power.

5. The communication bus network of claim 3, wherein the first EMB assembly comprises a first electronic control unit (ECU), and the second EMB assembly comprises a second ECU, wherein the first bus network extends between the first ECU and the second ECU and the EBB module, and The second bus network extends between the first ECU, the second ECU and the controller.

6. The communication bus network of claim 5, wherein the first ECU and the second ECU are operably coupled to a first wheel speed sensor and a second wheel speed sensor, respectively, the first wheel speed sensor providing the wheel speed for the first rear wheel to the first ECU and the second wheel speed sensor providing the wheel speed for the second rear wheel to the second ECU, and wherein in response to a loss of communication between the first ECU and the second ECU and both the controller and the EBB module, the first ECU and the second ECU apply parking brakes to the first rear wheel and the second rear wheel, respectively, when the first wheel speed sensor and the second wheel speed sensor each indicate zero wheel speed of the first rear wheel and the second rear wheel.

7. The communication bus network of claim 6, wherein the first ECU and the second ECU provide wheel-end anti-lock braking system (ABS) functions for the first rear wheel and the second rear wheel, respectively, in response to a loss of communication from the first wheel speed sensor and the second wheel speed sensor.

8. The communication bus network according to claim 5, wherein the first ECU and the second ECU each include a corresponding motor to provide braking torque to the first rear wheel and the second rear wheel, respectively, and The signaling for the operation of the respective motors of the first ECU and the second ECU is provided primarily via the controller through the second bus network, and in a backup case via the EBB module. 9 . The communication bus network according to claim 1 , wherein a brake pedal of the system is operably coupled to a controller, and a signaling for braking of the EBB module is received from the brake pedal by the controller.

10. A vehicle braking system, comprising: a first hydraulic brake assembly associated with a first front wheel; a second hydraulic brake assembly associated with a second front wheel; a front electronic brake booster (EBB) module operably coupled to the first hydraulic brake assembly and the second hydraulic brake assembly to control primary operations of the first hydraulic brake assembly and the second hydraulic brake assembly; a first electromechanical brake (EMB) assembly associated with a first rear wheel; a second EMB assembly associated with a second rear wheel; a controller operably coupled to the first EMB assembly and the second EMB assembly to control primary operations of the first EMB assembly and the second EMB assembly; a first power network and a second power network, the first power network and the second power network providing a redundant power supply to the system; as well as A communications bus network according to any one of claims 1 to 9.

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