BRAKE-BY-WIRE-SYSTEM

Abstract

Vehicle (100) with a fault-tolerant electronic brake-by-wire (BBW) system (102), the vehicle (100) comprising: a plurality of brake systems (118a-118d), each brake system (118a-118d) comprising an electromechanical actuator configured to adjust a torque applied to a wheel of the vehicle (100); a plurality of electronic brake system controllers (EB S controllers) (200a, 200b) arranged remotely, each EBS controller (200a, 200b) having an integrated electronic actuator driver unit (202a, 202b) with an integrated electronic power circuit configured to drive at least one of the electromechanical actuators (120a-120d), wherein each EBS control unit (200a, 200b) is electrically connected to the electromechanical actuator (120a-120d) contained in each brake system among the plurality of EBS control units (200a, 200b); and wherein the plurality of EBS controllers (200a, 200b) comprises a first EBS controller (200a) and a second EBS controller (200b) located remotely from the first EBS controller (200a), wherein the first and second EBS controllers (200a, 200b) are configured to operate selectively in a split topology mode or a full topology mode based on diagnostic results generated by at least one of the first and second EBS controllers (200a, 200b).

Description

BACKGROUND

[0001] The invention disclosed herein relates to vehicle braking systems and in particular to a vehicle with a brake-by-wire system (BBW system).

[0002] Current automotive industry trends aimed at reducing the number of mechanical components and the overall vehicle weight have contributed to the development of system-by-wire applications, typically referred to as X-by-wire systems. One such X-by-wire system that has garnered more attention is a brake-by-wire (BBW) system, sometimes called an electronic braking system (EBS).

[0003] Unlike conventional mechanical braking systems, brake-by-wire (BBW) systems actuate one or more vehicle braking components via an electrical signal generated by an onboard processor / controller or received from an external source. In some systems, a BBW system is implemented by replacing a conventional hydraulic fluid-based service brake system with an electrically based system to perform basic braking functions. Such a system typically includes a manually operated safety device that can be hydraulically actuated.

[0004] Because brake-by-wire (BBW) systems typically eliminate any direct mechanical links and / or hydraulic power transmission paths between the driver and the brake control units, considerable attention has been paid to the design of BBW control systems and control architectures to ensure reliable and robust operation. Various design techniques have been implemented to enhance the reliability of BBW systems, including redundancy, fault tolerance to undesired events (e.g., events affecting control signals, data, hardware, software, or other elements of such systems), fault monitoring, and recovery. One design approach to providing fault tolerance used in BBW brake control systems has been to include a mechanical backup system that can be used as an alternative means of braking the vehicle.

[0005] DE 103 20 608 B4 discloses a braking system for vehicles, in particular commercial vehicles, with at least one first and at least one second brake circuit, which can be electrically controlled via a foot brake valve, wherein the two brake circuits each have an electrical control circuit with control electronics and their own power supply unit and brake actuation devices that can be controlled by the control electronics, wherein at least one brake actuation device can be controlled by more than one control electronics, characterized in that the first brake circuit is a service brake circuit and the second brake circuit takes over the function of the first brake circuit in regular alternation controlled by the control electronics, wherein the inactive brake circuit is checked in each case.

[0006] US Patent 2005 / 0 225 165 A1 discloses a brake control system for wired brake applications with two monitoring controllers and a common monitoring controller to achieve a fail-safe architecture for the monitoring controllers. The brake control system also includes a mechanism by which the monitoring controller ensures the fail-safe operation of brake control units in the event of certain undesired events within the system by taking control of the affected brake control units. The brake control system further ensures that no single event, including an event related to the monitoring controller, results in a loss of more than half of the brake functionality.The brake control system is provided with additional redundancy with respect to the brake command signals by sharing a separate unprocessed brake command signal with each of the higher-level control units and the monitoring controller. SUMMARY

[0007] According to a non-restrictive embodiment, a vehicle is provided that incorporates a fault-tolerant electronic brake-by-wire (BBW) system. The vehicle comprises a plurality of brake systems and a plurality of electronic brake system (EBS) controllers. Each brake system includes an electromechanical actuator configured to adjust a torque force applied to a wheel of the vehicle. The plurality of EBS controllers are located remotely. Each EBS controller has an integrated electronic actuator driver unit that includes an electronic power circuit configured to drive at least one of the electromechanical actuators. Each EBS controller among the plurality of EBS controllers is electrically connected to the electromechanical actuator contained in each brake system.Furthermore, the multitude of EBS controllers includes a first EBS controller and a second EBS controller located remotely from the first EBS controller, with the first and second EBS controllers being configured to operate selectively in a split topology mode or a full topology mode based on diagnostic results generated by at least one of the first and second EBS controllers.

[0008] The aforementioned features and advantages, as well as further features and advantages of the invention, are readily apparent from the following detailed description of the invention in conjunction with the associated drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Other features, advantages and details appear only as examples in the following detailed description of the embodiments and the detailed description which refers to the following drawings: Fig. Figure 1 is a schematic top view of a vehicle with a BBW system according to a non-restrictive embodiment; Fig. Figure 2A is a schematic view of a BBW system based on a split-EBS control topology according to a non-restrictive embodiment; Fig. Figure 2B is a schematic view of a BBW system based on a split-EBS control topology, according to another non-restrictive embodiment; Fig. Figure 2C is a schematic view of a BBW system based on a full-full EBS control topology according to a non-restrictive embodiment; Fig. Figure 3 is a block diagram representing a plurality of EBS controls included in a BBW system according to a non-restrictive embodiment; and Fig. Figure 4 is a flowchart that illustrates a method for controlling a fault-tolerant BBW system according to a non-restrictive embodiment. DESCRIPTION OF THE EXECUTION FORMS

[0010] The following description is merely exemplary and is not intended to limit the present disclosure in its applications or uses. It should be noted that in all drawings the same reference numerals refer to the same or corresponding parts and features.

[0011] Various non-restrictive embodiments provide a fault-tolerant BBW system that includes several independent BBW components to ensure maximum flexibility in the physical packaging. In at least one embodiment, the vehicle comprises a plurality of brake systems, each comprising a respective actuator unit that controls a braking torque applied to the wheels. At least one brake system (e.g., a first brake assembly) among the plurality of brake systems comprises an electromechanical actuator that operates in response to a first high-frequency switched high-power signal, while at least one other brake system (e.g.,(A second braking system) among the multiple braking systems has a second electromechanical actuator that operates in response to a second high-frequency switched high-power current signal, which differs from the first high-frequency switched high-power current signal. The high-frequency switched high-power signals can have a frequency in the range of approximately 15 kilohertz (kHz) to approximately 65 kHz and a current value of approximately 0 A to approximately 200 A.

[0012] Additionally, the vehicle incorporates a multitude of individual electronic braking system (EBS) controllers. According to a non-restrictive embodiment, a first EBS controller has an integrated first actuator driver, and a second EBS controller has an integrated second actuator driver. The actuator driver generates the first high-frequency switched high-power current signal, while a second actuator driver generates the second high-frequency switched high-power current signal. Accordingly, a flexible brake-bending (BBW) system is provided, allowing for flexible design choices while removing digital processing operations from the electromechanical actuators and also reducing the overall cost of the brake systems. Furthermore, the EBS controllers are capable of suspending the power supply to a faulty actuator to implement fault tolerance in the BBW system.

[0013] With reference to Fig. Figure 1 is a vehicle 100 with a fault-tolerant brake booster (BBW) system 102 configured to electronically control the braking of the vehicle 100, as shown in a non-limiting embodiment. The vehicle 100 is driven by a powertrain system comprising an engine 104, a transmission 108, and a transfer case 110. The engine 104 comprises, for example, an internal combustion engine 104 configured to generate drive torque that drives the front wheels 112a and 112b and the rear wheels 114a and 114b using various components of the vehicle drive system. Various types of engines 104 can be used in the vehicle 100, including, but not limited to, a diesel engine, a gasoline engine, and a hybrid engine combining an internal combustion engine with, for example, an electric motor.The fault-tolerant BBW system can also be implemented in a battery-powered electric vehicle with an electric motor without departing from the scope of the invention.

[0014] The vehicle powertrain can be understood as comprising the various powertrain components, with the exception of the engine 104. According to a non-limiting embodiment, the drive torque is transmitted to the transmission 108 via a rotatable crankshaft (not shown). Thus, the torque supplied to the transmission 108 can be adjusted in various ways, including, for example, by controlling the operation of the engine 104, as will be understood by those skilled in the art.

[0015] The fault-tolerant BBW system 102 comprises a pedal assembly 116, brake systems 118a-118d (i.e., brake corner modules), one or more actuator units 120a-120d, one or more wheel sensors 122a and 122b, and one or more electronic brake system (EBS) controllers 200. Although two wheel sensors 122a and 122b are shown, it is understood that additional wheel sensors, e.g., four wheel sensors, can be included without deviating from the scope of the invention.

[0016] The pedal assembly 116 communicates with the EBS controller 200 and includes a brake pedal 124, one or more pedal force sensors 126, and one or more pedal travel sensors 128. The pedal assembly 116 can be any combination of hardware and software that enables a component of the fault-tolerant BBW system 102 to behave like a component that is not part of the fault-tolerant BBW system 102. For example, the pedal assembly 116 can be a pedal emulator that behaves like a pushable mechanical pedal of a hydraulic brake system. In at least one embodiment, the pedal assembly 116 can be constructed exclusively by electronic wiring and software, while omitting various mechanical or hydraulic components found in conventional pedal assemblies.

[0017] The EBS controller 200 is configured to detect the brake pedal travel or braking force applied to the brake pedal 124 based on the respective signal outputs from pedal force sensor 126 and pedal travel sensor 128. According to a non-limiting embodiment, the pedal force sensor 126 is configured as a pressure transducer or other suitable pressure sensor that is capable of accurately detecting, measuring, or otherwise determining an application pressure or force exerted on the brake pedal 124 by the operator of vehicle 100. The pedal travel sensor 128 can be configured or set as a pedal position and range sensor such that it accurately detects, measures, or otherwise determines the relative position and direction of travel of the brake pedal 124 along a fixed range of motion when the brake pedal 124 is depressed or actuated.

[0018] The measurements or values ​​obtained by the pedal force sensor 126 and the pedal travel sensor 128 are transmissible or communicable with one or more EBS controllers 200, or are otherwise determinable as required for use with one or more braking algorithms stored in the memory of the EBS controller 200. The EBS controller 200 is also configured to calculate, select, and / or determine an appropriate braking request or braking event in response to the detected and recorded measurements or values ​​output by the wheel sensors 122a and 122b. Based on the determined braking request or braking event, the EBS controller 200 outputs a low-voltage data command signal that invokes a braking action to decelerate the vehicle 100, as discussed in detail below.

[0019] The wheel sensors 122a and 122b can provide various types of vehicle data, including, but not limited to, speed, acceleration, deceleration, and vehicle angle relative to the road surface and wheel slip. In at least one embodiment, the fault-tolerant BBW system 102 can include one or more object detection sensors 129 located at various points on the vehicle 100. The object detection sensors 129 are configured to detect the movement and / or presence of various objects surrounding the vehicle, including, but not limited to, surrounding vehicles, pedestrians, traffic signs, and road hazards. The EBS controller 200 can determine a scenario (e.g., a request and / or a need) to decelerate and / or stop the vehicle based on the data provided by the pedal assembly 116, the wheel sensors 122a and 122b, and / or the object detection sensor 129.In response to the determination of the braking scenario, the EBS control unit 200 communicates a braking command signal to one or more brake systems 118a-118d to slow down or stop the vehicle 100.

[0020] In at least one embodiment, the EBS control unit 200 is integrated with an electronic actuator driver component, such as an electronic power circuit. In this way, the EBS control unit 200 is able to output a high-frequency switched high-power signal to drive the electromechanical actuators 120a-120d contained in a respective brake system 118a-118d, as discussed in more detail herein.

[0021] The EBS 200 controller also includes programmable memory (not in Fig. 1 shown) and a microprocessor (not shown in Fig. 1 shown). In this way, the EBS control 200 is able to quickly execute the required control logic to implement and control the actuators 120a-120d by using a brake pedal transition logic procedure or algorithm that is programmed or stored in memory.

[0022] Additionally, the EBS controller 200 (e.g., the memory) can be preloaded or preprogrammed with one or more brake torque lookup tables (LUTs), i.e., brake torque data tables that are readily accessible to the microprocessor for performing or executing a braking algorithm. In at least one embodiment, the brake torque LUT stores recorded measurements or readings from the pedal force sensor 126 and contains an associated commanded brake request suitable for each of the detected force measurements as determined by the pedal force sensor 126. Similarly, the EBS controller 200 stores a pedal position LUT corresponding to the measurements or readings from the pedal travel sensor 128 and contains a commanded brake request for the detected position of the pedal travel sensor 128.

[0023] According to at least one embodiment, the fault-tolerant BBW system 102 can also be a separation module (not in Fig. 1 shown) and one or more power sources (not shown in Fig. (shown in Figure 1). The isolation module can be designed as an electrical circuit and is configured to isolate circuit faults, such as wire-to-wire short circuits, on a signal line loop (SLC loop). The isolation module also limits the number of modules or detectors that can be affected by a circuit fault (e.g., short circuit to ground or voltage, etc.) on the SLC loop or by a circuit fault in one or more power sources 204a-204b. Fig. 2, (e.g., undervoltage, overvoltage, etc.) can be taken out of service. According to a non-restrictive embodiment, when a circuit fault condition occurs, the isolation module can automatically create an interruption (disconnection) in the SLC loop to isolate the brake systems 118a-118d from a circuit fault condition. Additionally, if a power source fails, the isolation module can disconnect the failed power source while maintaining the remaining power sources. In this way, according to a non-restrictive embodiment, the fault-tolerant BBW system 102 provides at least one fault-tolerant feature that can enable one or more brake systems 118a-118d to avoid failure if a circuit fault condition occurs in the EBS 200. When the circuit fault condition is resolved, the isolation module can disconnect the isolated section of the SLC loop, e.g.,The brake systems 118a-118d will automatically reconnect.

[0024] In Fig. Sections 2A-2C illustrate different embodiments of a fault-tolerant BBW system. Firstly, with reference to... Fig. 2A is a fault-tolerant BBW system 102 based on a split-EBS control topology, as shown in a non-restrictive embodiment. The fault-tolerant BBW system 102 includes a plurality of brake systems 118a-118d. Each brake system 118a-118d includes an electromechanical actuator 120a-120d that controls a braking torque applied to a respective wheel 112a and 112b / 114a and 114b. The actuator unit 120a-120d may include, but is not limited to, a motor that drives an electronic brake caliper (e-caliper). The motor operates in response to a high-frequency switched high-power signal (shown as dashed arrows) and in turn drives the electric brake caliper, which exerts a variable frictional force to slow down wheels 112a / 112b-114a and 114b in response to receiving a stop command. The stop command can be initiated manually by a driver or...be provided autonomously by a vehicle system.

[0025] The fault-tolerant BBW system 102 also includes a variety of EBS controllers 200a and 200b. According to the in Fig. In the split-control topology shown in Figure 2A, the first EBS controller 200a drives a first group of brake actuators 120b / 120d, while the second EBS controller 200b controls a second group of brake actuators 120a / 120c. Each EBS controller 200a and 200b is integrated with a hardware processor (e.g., microcontroller) 306a and 306b and memory units 308a and 308b that store executable instructions, including, but not limited to, brake algorithms and self-diagnostic algorithms (see Figure 2A). Fig. 3) The hardware processors 306a and 306b are configured to read and execute the instructions stored in their respective memory units 308a and 308b to control the fault-tolerant BBW system 102, as described in more detail below.

[0026] As mentioned above, the EBS controllers 200a and 200b are also integrated with the respective electronic actuator driver units 202a and 202b. The EBS controllers 200a and 200b receive one or more input data signals 300 supplied by one or more vehicle sensors (e.g., wheel sensors 122a-122d) and, in turn, initiate a respective power circuit 202a and 202b, as described herein. After initiation, the power circuits 202a and 202b can output a high-frequency switched high-power signal 310 (represented by dashed arrows) to drive an electromechanical actuator 120a-120d contained in a respective brake system 118a-118d. The first and second EBS controllers 200a and 200b can also share various data 304 with each other (see Fig. 3) The shared data includes, for example, detected braking demands and diagnostic results obtained after performing self-diagnostic tests.

[0027] The actuator driver units 202a and 202b can be configured as one or more electronic power circuits 202a and 202b, including, but not limited to, a pulse width modulation circuit, a power amplifier circuit, H-bridges, heat sinks, application-specific integrated circuits (ASICs), controller area network (CAN) transceivers, or temperature or current sensors. The actuator driver units 202a and 202b each receive a constant high-power input signal (e.g., an unswitched high-power input current) from a respective current source 204a and 204b. The high-power input signal can be a high-power current signal in the range of approximately 0 amperes to approximately 200 amperes.

[0028] In response to receiving a brake event data command signal from a respective EBS controller 200a and 200b, each actuator driver unit 202a and 202d is configured to output a high-frequency switched high-power signal to a respective electromechanical actuator 120a-120d. In at least one embodiment, the power circuits 202a and 202b generate a high-frequency switched high current with a frequency that can range from about 15 Hz to about 65 Hz and a current that can range from about 0 amperes to about 200 amperes. In turn, the high-frequency switched high-current signal drives the actuator, e.g., B. a motor that then adjusts the E-brake caliper so that a braking force is exerted on each wheel 112a and 112b / 114a and 114b, which is necessary to slow down or stop the vehicle as determined by the first EBS control 200a.Although only one section of the fault-tolerant BBW system 102 controlled by the first EBS controller 200a has been described, it is understood that the second section of the fault-tolerant BBW system 102 controlled by the second EBS controller 200b can operate in a similar manner as discussed above.

[0029] What next in the Fig. As illustrated in Figures 2A-2C, the EBS controllers 200a and 200b are located remotely from the brake systems 118a-118d, yet remain electrically connected to output the high-frequency switched high-power signal to the electromechanical actuators 120a-120d. The location of the EBS controllers 200a and 200b is also flexible and not restricted to a specific area of ​​the vehicle 100. This allows the EBS controllers 200a and 200b to be located in close proximity to an associated brake system 118a-118d, thereby reducing the length of the high-current wires that supply the high-frequency switched high-power signal to drive a respective electromechanical actuator 120a-120d.

[0030] In at least one embodiment, the first EBS controller 200a is electrically connected to the second EBS controller 200b via a communication interface. The communication interface includes, but is not limited to, FlexRay™, Ethernet, and a low-voltage message-based interface, such as a CAN bus. In this way, the first and second EBS controllers 200a and 200b can share data. FlexRay™ is a high-speed, fault-tolerant, time-controlled protocol with static and dynamic frames. FlexRay™ can support high data rates of up to 10 Mbit / s.

[0031] In at least one embodiment, the first EBS control unit 200a is electrically connected to a first brake system 118b configured to brake a first wheel 112b located on the passenger side of the vehicle 100 (e.g., the passenger-side wheel 112b) and a second brake system 118d configured to brake a second wheel 114a located diagonally from the first brake system 118b, i.e., on the driver's side of the vehicle 100 (e.g., the rear driver-side wheel 114a). Similarly, the second EBS control unit 200b is electrically connected to a third brake system 118a, which is configured to brake a third wheel 112a located on the driver's side of the vehicle 100 (e.g., the front driver's side wheel 112a), and a fourth brake system 118c, which is configured to brake a fourth wheel 114b located diagonally from the third brake system 118c, i.e., on the passenger side of the vehicle 100 (e.g., the front passenger side wheel 112a).the rear passenger-side wheel 114b). Accordingly, the in . Fig. The split control topology shown in Figure 3A can be referred to as a diagonal split control topology.

[0032] In another embodiment, the split control topology can be constructed as a front / rear split control topology, as shown in Fig. Figure 2B shows this embodiment. In this embodiment, the first EBS control unit 200a is electrically connected to the brake system 118a, which is located on the front driver's side of the vehicle 100, and to the brake system 118d, which is located on the rear driver's side of the vehicle 100. Similarly, the second EBS control unit 200b is electrically connected to the brake system 118b, which is located on the front passenger's side of the vehicle 100, and to the brake system 118c, which is located on the rear passenger's side of the vehicle 100.

[0033] In each of the topologies described above, the EBS controllers 200a and 200b can be configured to monitor the condition of the vehicle 100 based on inputs provided by one or more sensors. The sensors include, but are not limited to, the wheel sensors 122a-122d and data signal output from the pedal assembly 116. Although in Fig. Not shown in Figure 2A, the pedal assembly 116 includes various sensors that monitor the pedal 124, including, but not limited to, a pedal force sensor and a pedal travel sensor, as detailed herein. The outputs of the pedal force sensor and the pedal travel sensor can be fed to both the first EBS controller 200a and the second EBS controller 200b to provide output redundancy. In at least one embodiment, the fault-tolerant BBW system can include multiple pedal force sensors and multiple travel sensors to achieve output redundancy. Based on the state of the vehicle 100, the first EBS controller 200a and / or the second EBS controller 200b determines whether to invoke a braking event to decelerate and / or stop the vehicle.When a braking event is detected, the first and second EBS controllers 200a and 200b each output a low-voltage data command signal to a respective group of power circuits 202a and 202b. The low-voltage data command signals can be provided via the CAN bus to a corresponding power circuit 202a or 202b.

[0034] By implementing a low-voltage message-based interface, the first and second EBS controllers 200a and 200b can also conveniently communicate data with each other. In this way, the first EBS controller 200a can inform the second EBS controller 200b about various detected braking events, and vice versa. The first and second EBS controllers 200a and 200b can also share self-diagnostic data. Therefore, each controller 200a and 200b can compare data received from each other to diagnose the fault-tolerant BBW system 102, for example, to determine whether the fault-tolerant BBW system 102 is operating correctly.

[0035] In at least one embodiment, an isolation module 206 is connected between the first and second power sources 204a and 204b and the remaining electrical system of the fault-tolerant BBW system 102. The isolation module 206 is configured to receive constant high-power signals generated by the first and second power sources 204a and 204b and to generate a variety of individual power input signals that are supplied to the EBS controllers 200a and 200b and the power circuits 202a and 202b. For example, the isolation module 206 outputs first and second constant high-voltage power signals to each power circuit 202a and 202b, as detailed above. The isolation module 206 also outputs first and second low-voltage signals that supply the first and second EBS controllers 200a and 200b, respectively.In at least one embodiment, the first and second EBS controllers 200a and 200b are electrically connected to the isolation module 206. In this way, the first and second EBS controllers 200a and 200b can receive various diagnostic information and circuit fault information, including, but not limited to, short-circuit events, open-circuit events, and overvoltage events.

[0036] As mentioned above, the isolation module 206 can also be configured to isolate circuit faults, including, for example, wire-to-wire short circuits on a signal line loop (SLC), and is capable of limiting the number of modules or detectors that can be disabled by a short-circuit fault on the SLC loop. According to a non-limiting embodiment, when a wire-to-wire short circuit occurs, the isolation module 206 can automatically create an interruption (disconnection) in the SLC loop to isolate the brake systems 118a-118d from a short-circuit fault condition. In this way, according to a non-limiting embodiment, the fault-tolerant BBW system 102 provides at least one fault-tolerant feature that can enable one or more brake systems 118a-118d to avoid failure if a short-circuit condition occurs in the EBS 200.When the short circuit condition is rectified, the disconnect module 206 can automatically reconnect the isolated section of the SLC loop, e.g. the brake systems 118a-118d.

[0037] With current reference to Fig. 2C is a fault-tolerant BBW system 102 based on a full electronic braking system (full EBS) control topology, as illustrated in a non-restrictive embodiment. The full EBS control topology of Fig. 2C operates similarly to the split-EBS control topology described above, with reference to the Fig. 2A and Fig. 2B. The complete EBS system from Fig. 2C differs in that each EBS controller 200a and 200b communicates electrically with each integrated power circuit 202a and 202b. For example, each EBS controller 200a and 200b can drive all electromechanical brake actuators 120a-120d via integrated power circuits 202a and 202b. In this way, if the first EBS controller 200a is unable to properly control the first power circuit 202a, the second EBS controller 200b can output the high-frequency switched high-power signal necessary to drive each electromechanical actuator installed on the vehicle 100. That is, each electromechanical actuator 120a-120d can only be controlled by the initiated EBS controllers (e.g., a single EBS controller 200a).Additionally, a first actuator controller 200a can output a low-voltage data command signal to the second electronic actuator driver 202b, which is integrated within the second actuator controller 200b. This allows the fault-tolerant BBW system 102 to use the high-frequency switched high-power signal supplied by the second actuator driver unit 202b, even if the hardware processor 306b of the second actuator controller 200b is operating abnormally. Accordingly, the full-control BBW topology can provide additional fault tolerance functionality.

[0038] According to at least one embodiment, the complete EBS control topology includes a plurality of electronic braking system (EBS) controllers, wherein each EBS controller 200a and 200b is electrically connected to each power circuit 202a and 202b, respectively, within the plurality of EBS controllers. Additionally, the power circuits 202a and 202b are located remotely from the brake systems 120a-120d, the first EBS controller 200a, and the second EBS controller 200b. Although the power circuits 202a and 202b can operate independently, each EBS controller 200a and 200b is configured to output a data control signal to control any one of the power circuits 202a and 202b.

[0039] According to at least one embodiment, the EBS controllers 200a and 200b are configured to operate selectively in a split-topology mode and a full-topology mode, based on data monitored by one or more EBS controllers 200a and 200b. The monitored data includes, but is not limited to, diagnostic results obtained in response to self-diagnostic operations performed by the first and / or second EBS controller 200a and 200b. For example, when operating in split-topology mode, the first EBS controller 200a controls a first group of electromechanical actuators 120b / 120d, while the second EBS controller 200b controls a second group of electromechanical actuators 120a / 120c.However, during operation in full topology mode, either the first EBS controller 200a or the second EBS controller 200b controls the electromechanical actuators 120a-120d of each of the 100 brake systems 118a-118d installed in the vehicle. That is, during operation in full topology mode, either the first EBS controller 200a or the second EBS controller 200b can control all electromechanical actuators 120a-120d.

[0040] As mentioned above, the EBS controllers 200a and 200b can enter full EBS topology mode based on diagnostic results obtained in response to a self-diagnostic test. For example, the first EBS controller 200a can perform an initial self-diagnostic operation and transmit initial diagnostic results to the second EBS controller 200b. Similarly, the second EBS controller 200b can perform its own second self-diagnostic operation and transmit second diagnostic results to the first EBS controller 200a. Full EBS topology mode can then be initiated if the initial diagnostic results and / or the second diagnostic results indicate an error.For example, if the second diagnostic results provided by the second EBS controller 200b indicate a fault, the first EBS can instruct the second EBS module 200b to enter standby or offline mode in order to activate full EBS topology mode and, in turn, control all power circuits 202a and 202b contained in the fault-tolerant BBW system 102. In this way, if the second EBS controller 200b contains a fault, the fault-tolerant BBW system 102 can still be fully operated by the first EBS controller 200a, thus providing a fault tolerance feature.

[0041] With reference to Fig.Figure 4 shows a flowchart of a method for controlling a fault-tolerant brake brake system according to a non-restrictive embodiment. The method begins at operation 400 and operation 402. Sensor data is output to a first EBS controller and a second EBS controller. The sensor data can be output by various sensors installed on the vehicle, including, but not limited to, wheel sensors, brake pedal sensors, and / or object detection sensors. At operation 404, it is determined whether at least one EBS controller detects a braking event. The braking event is based on the sensor data described above. If no braking event is detected, the method returns to operation 402 and continues monitoring the sensor data.

[0042] However, if at least one of the EBS controllers detects a braking event, the first and second EBS controllers communicate with each other to compare their respective detected braking event data. For example, a first EBS controller may detect a braking event and request confirmation that the second EBS controller has detected the same or a similar braking event. If the braking event data monitored and generated by the first EBS controller matches or substantially matches the braking event data monitored and generated by the second EBS controller, the procedure proceeds to Operation 408, wherein the first EBS controller initiates a first electronic actuator driver integrated therein, and the second EBS controller initiates a second electronic actuator driver integrated therein. In this way, separate actuator drivers are controlled independently by separate actuator controllers.In operation 410, the first actuator driver unit outputs one or more high-frequency switched high-power signals that drive a first group of electromechanical actuators, and the second actuator driver unit outputs one or more high-frequency switched high-power signals that drive a second group of electromechanical actuators that excludes the actuators of the first group.

[0043] In at least one embodiment, the first group of actuators includes a first electromechanical actuator installed in a first brake system and a second electromechanical actuator installed in a second brake system. The first brake system controls a first wheel (e.g., the passenger-side front wheel), and the second brake system is located remotely from the first brake system and controls a second wheel that is different from the first wheel (e.g., the driver-side rear wheel). Similarly, the second group of actuators includes a third electromechanical actuator installed in a third brake system and a fourth electromechanical actuator installed in a fourth brake system. The third brake system controls a third wheel (e.g., the rear wheel on the driver's side).the driver's side front wheel) and the fourth brake system is located away from the third brake system and controls a fourth wheel that is different from the first wheel (e.g. the passenger side rear wheel).

[0044] In operation 412, the first actuator sets a first braking torque applied to the first wheel, and the second actuator sets a second braking torque applied to the second wheel. Similarly, the third actuator sets a third braking torque applied to the third wheel, and the fourth actuator sets a fourth braking torque applied to the fourth wheel. In this way, the vehicle can be slowed down or stopped according to the braking event detected by the first and second EBS controllers, and the procedure ends at 414.

[0045] Referring to Operation 406, a scenario may occur in which the braking event data monitored and generated by the first EBS controller does not match or substantially match the braking event data monitored and generated by the second EBS controller. In this case, the procedure proceeds to Operation 416, in which either the first EBS controller or the second EBS controller initiates its respective integrated electronic actuator driver unit. In Operation 418, the initiated electronic driver unit outputs one or more high-frequency switched high-power signals to drive the electromechanical actuators in each braking system installed on the vehicle. That is, each electromechanical actuator can be controlled only by the initiated EBS controllers (e.g., a single EBS controller).This fault-tolerant function allows the vehicle's braking system to operate if an EBS controller or a section of the BBW (including the sensors communicating with a specific EBS controller) connected to a specific EBS controller or actuator driver unit of a given EBS experiences a fault. In operation 420, one or more electromechanical actuators apply a braking torque to a given wheel, and the procedure ends in operation 414. In this way, the vehicle can be decelerated in response to a detected braking event, even if one or more of the EBS controllers or integrated actuator driver units are not operating as expected.

[0046] As described in detail above, various non-restrictive embodiments provide a fault-tolerant BBW system that strategically separates one or more BBW components to ensure maximum flexibility in physical packaging. In at least one embodiment, for example, the BBW system comprises a plurality of individual electronic braking system (EBS) controllers, each controlling at least one braking system. A first EBS controller controls a first power circuit, while a second EBS controller, distinct from the first, controls a second power circuit. Additionally, the first and second power circuits are located remotely from the respective braking systems that supply them with power.Accordingly, a flexible BBW system is provided, allowing for flexible design choices, reduced wire lengths, and flexible brake algorithm implementation, while still incorporating fault tolerance into the system. Furthermore, separating the power circuits from the EBS controllers and brake systems eliminates the need for additional thermal mitigation measures.

[0047] As used herein, the term “module” or “unit” refers to an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), an electronic circuit, an electronic computer processor (shared, dedicated, or grouped), and memory that executes one or more software or firmware programs, a combinational logic circuit, and / or other suitable components providing the described functionality. When implemented in software, a module may be implemented in memory as a non-volatile, computer-readable storage medium that can be read by a processing circuit and stores instructions to be executed by the processing circuit to carry out a procedure.

[0048] While the embodiment has been described with reference to exemplary embodiments, those skilled in the art will understand that various modifications can be made and individual parts can be replaced by corresponding other parts without deviating from the scope of the embodiments. Furthermore, many modifications can be made to adapt a particular situation or specific materials to the teachings of the exemplary embodiments without deviating from their essential scope. Therefore, it is intended that the invention is not limited to the disclosed specific embodiments, but that the disclosure also includes all embodiments that fall within the scope of the application.

Claims

[1] Vehicle (100) with a fault-tolerant electronic brake-by-wire (BBW) system (102), comprising the vehicle (100): a plurality of brake systems (118a-118d), each brake system (118a-118d) comprising an electromechanical actuator configured to adjust a torque applied to a wheel of the vehicle (100); a plurality of electronic brake system controllers (EB S controllers) (200a, 200b) arranged remotely, each EBS controller (200a, 200b) having an integrated electronic actuator driver unit (202a, 202b) with an integrated electronic power circuit configured to drive at least one of the electromechanical actuators (120a-120d), wherein each EBS control unit (200a, 200b) is electrically connected to the electromechanical actuator (120a-120d) contained in each brake system among the plurality of EBS control units (200a, 200b); and wherein the plurality of EBS controllers (200a, 200b) comprises a first EBS controller (200a) and a second EBS controller (200b) located remotely from the first EBS controller (200a), wherein the first and second EBS controllers (200a, 200b) are configured to operate selectively in a split topology mode or a full topology mode based on diagnostic results generated by at least one of the first and second EBS controllers (200a, 200b). [2] Vehicle (100) according to claim 1, wherein the electronic actuator driver unit (202a, 202b) includes a pulse width modulation circuit (PWM circuit) in signal connection with a power amplifier circuit to generate a high-frequency switched high-power signal. [3] Vehicle (100) according to claim 2, wherein each electronic actuator driver unit (202a, 202b) integrated in a respective EBS controller (200a, 200b) among the plurality of EBS controllers (200a, 200b) is configured to output the high-frequency switched high-power signal to drive an electromechanical actuator (120a-120d) contained in any brake system (118a-118d). [4] Vehicle (100) according to claim 1, wherein, in split-topology mode, the first EBS controller (200a) controls a first group of brake systems among the plurality of brake systems (118a-118d) and the second EBS controller (200b) controls a second group of brake systems among the plurality of brake systems (118a-118d), and wherein, in full-topology mode, either the first EBS controller (200a) or the second EBS controller (200b) controls both the first group of brake systems and the second group of brake systems.

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