Redundant brake actuation based on electronic stability control

Abstract

The present invention provides a redundant brake drive based on electronic stability control. The braking system includes an electronic stability control (ESC) module defining a first interconnected channel and a pressure supply unit (PSU) module defining a second interconnected channel in fluid communication with the first interconnected channel. The ESC module includes a first pump configured to transfer brake fluid from the PSU module and to a plurality of wheel brake parts, and a starter valve configured to selectively control the fluid communication between the first interconnected channel and the inlet of the first pump. The PSU module includes a second pump configured to transfer brake fluid from a fluid storage part to the first interconnected channel, and a bypass fluid channel from the fluid storage part to the ESC module having a straight-through check valve, the straight-through check valve allowing fluid to flow from the fluid storage part through the bypass fluid channel and to the ESC module while preventing fluid from flowing in the opposite direction.

Description

Technical Field

[0001] The present disclosure relates generally to braking systems for vehicles such as automobiles. More particularly, the present disclosure relates to a braking system that can be used with level 4 autonomous drive. Background Art

[0002] Autonomous vehicles need to provide braking without driver input. Typically, these solutions are provided by an integrated (one-box) braking system that provides brake application (actuation) and brake modulation (ABS / ESC), all built into a single hardware box. Additional brake units are integrated into this box or added separately to provide redundancy for brake application and possibly brake modulation (ABS / ESC). These types of systems are very powerful but can be quite expensive. Summary of the Invention

[0003] The present invention provides a braking system for a motor vehicle. The braking system includes two brake-related modules, an electronic stability control (ESC) module defining a first interconnected channel and a pressure supply unit (PSU) module defining a second interconnected channel in fluid communication with the first interconnected channel of the ESC module. The ESC module includes a first pump configured to transfer brake fluid from the PSU module and transfer the brake fluid to a plurality of wheel brake units, and a prime valve configured to selectively control fluid communication between the first interconnected channel and the inlet of the first pump. The PSU module includes a second pump configured to transfer the brake fluid from a fluid reservoir to the first interconnected channel of the ESC module, and a bypass fluid channel having an inline check valve. The bypass fluid channel is configured to transfer the brake fluid directly from the fluid reservoir to the ESC module and bypass the second pump. The inline check valve is configured to allow fluid to flow from the fluid reservoir through the bypass fluid channel and to the ESC module, while preventing fluid from flowing in the opposite direction.

[0004] The present invention also provides a braking system for a motor vehicle. The braking system includes an electronic stability control (ESC) module defining a first interconnected channel, and a pressure supply unit (PSU) module defining a second interconnected channel in fluid communication with the first interconnected channel of the ESC module. The ESC module includes a first electronic control unit (ECU) and a first pump, the first pump being configured to transfer brake fluid from the PSU module and to transfer the brake fluid to a plurality of wheel brake portions. The PSU module includes a second ECU and a second pump configured to transfer the brake fluid from a fluid storage portion to the first interconnected channel of the ESC module, and a bypass fluid channel having a straight-through check valve. The bypass fluid channel is configured to deliver the brake fluid directly from the fluid storage portion to the ESC module and bypass the second pump. The straight-through check valve is configured to allow fluid to flow from the fluid storage portion through the bypass fluid channel and to the ESC module, while preventing fluid from flowing in the opposite direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Other advantages of the present invention will be readily appreciated as they become better understood by reference to the following detailed description considered in conjunction with the accompanying drawings, in which:

[0006] Figure 1 shows a schematic diagram of a first braking system according to one aspect of the present disclosure;

[0007] Figure 2 shows a schematic diagram of a second braking system according to one aspect of the present disclosure;

[0008] Figure 3 shows a schematic block diagram illustrating the functional interconnection between vehicle systems including a second braking system;

[0009] Figure 4 shows a schematic block diagram illustrating the hydraulic interconnections of the second brake system;

[0010] Figure 5 shows a schematic block diagram illustrating the electrical interconnections of the second brake system;

[0011] Figure 6 shows a schematic diagram of a second braking system according to one aspect of the present disclosure;

[0012] Figure 7 A schematic diagram of a third braking system according to one aspect of the present disclosure is shown. DETAILED DESCRIPTION

[0013] With reference to the accompanying drawings, the present invention will be described in detail according to the following embodiments.

[0014] The system of the present disclosure may be adapted for Level 4 or higher automation based on SAE International's "Levels of Automated Driving" standard, which defines six levels of driving automation as specified in SAE Standard J3016. Level 4 automation enables a vehicle to be fully autonomous (i.e., without a driver), but may be subject to speed and operating area limitations. This type of vehicle may include a shuttle that moves around, transporting passengers or packages at a certain maximum speed within a defined area.

[0015] The braking system of the present disclosure may interact with an autopilot controller and software stack that may issue commands to the braking units via CAN messaging or alternative bus messaging to implement the desired level of braking.

[0016] The present disclosure provides for service braking performed by two off-the-shelf electronic stability control (ESC) units, one of which is modified into a dedicated pressure supply unit (PSU) built in a manner that provides redundancy. An additional benefit also provided in this dual-module approach is distributed EPB (Electric Parking Brake) control, which also provides continued EPB functionality in the event of a failure of the ECU (Electronic Control Unit) driving the EPB.

[0017] The braking system of the present disclosure can include a fully standard 12-valve ESC unit and a PSU unit to provide redundant brake actuation and standard ABS / ESC in an economical two-box package. Actuation redundancy is provided by one ESC unit and one PSU unit connected in series. ABS / ESC modulation is provided by the ESC unit. Each unit can provide brake actuation. In some embodiments, the typical brake actuation function alternates between each unit each time the brakes are applied. This allows wear on the units to be evenly distributed among them.

[0018] Figure 1A schematic diagram of a first braking system 10 according to one aspect of the present disclosure is shown. The first braking system 10 is configured to provide the redundant braking operation required for Level 4 automation or higher. The first braking system 10 includes a master electronic hydraulic control unit (EHCU) 20 hydraulically connected to four wheel brakes 22a, 22b, 22c, and 22d. The master EHCU 20 can be a fully functional device, including the ability to generate fluid pressure for applying each of the wheel brakes 22a, 22b, 22c, and 22d, as well as for controlling the distribution of fluid to provide functions such as anti-lock braking and electronic stability control. The wheel brakes 22a, 22b, 22c, and 22d can each be connected to a corresponding wheel (not shown) of the vehicle and can also be referred to as foundation brakes to stop the vehicle. A fail-safe EHCU 24 is hydraulically coupled to the master EHCU 20 to provide fluid for operating the wheel brakes 22a, 22b, 22c, and 22d in the event that the master EHCU 20 becomes unavailable. A fallback EHCU 24 also communicates with the primary EHCU 20 via a controller area network (CAN) interconnect 26. However, other communication interfaces may be used.

[0019] The first braking system 10 works well, but the cost of the main EHCU 20 is very high due to the incorporation of components such as brushless motors, ball screws, and corresponding controls required for the system to operate correctly. This type of unit has a very fast response time, which in many cases is much faster than necessary for some Class 4 applications where speed limits are a concern.

[0020] Figure 2 A schematic diagram of a second braking system 50 according to one aspect of the present disclosure is shown. The second braking system 50 is also configured to provide redundant braking operations required for level 4 or higher levels of automation. The second braking system 50 can provide a cost advantage over the first braking system 10. The second braking system 50 includes an electronic stability control (ESC) module 52 and a PSU module 54, which is packaged similarly to the ESC module 52 and shares common components. The ESC module 52 and the PSU module 54 can be derived from the same basic ESC design package to save manufacturing costs. The ESC module 52 can be a full-featured ESC, while the PSU module 54 can be used primarily for failover and basic brake application. If automatic braking is required at any speed, either module 52, 54 can provide braking. The storage unit 58 stores fluid to be used directly by the PSU module 54 or indirectly by the ESC module 52.

[0021] Each of the modules 52, 54 can include a pump driven by an electric motor and one or more solenoid valves to control the distribution of pressurized fluid for operating the wheel brake portions 22a, 22b, 22c, 22d. The ESC module 52 and the PSU module 54 can be configured as an integrated package including a pump and a corresponding motor, an electronic control unit (ECU), and a hydraulic control unit (HCU), the HCU including valves with associated fluid channels and hydraulic accessories for distributing brake fluid to operate the wheel brake portions 22a, 22b, 22c, 22d. The ESC module 52 and the PSU module 54 can be housed in modules of almost identical appearance, such as the DBC1280ESC device. The second braking system 50 can also utilize regenerative braking, particularly at higher speeds.

[0022] The second braking system 50 also includes two rear wheel brake units 22c, 22d of the wheel brake units 22a, 22b, 22c, 22d configured with electric parking brake (EPB) calipers 56. Each of these EPB calipers 56 includes an electric actuator that is configured to apply brakes in addition to or instead of applying them hydraulically. In other words, each EPB caliper 56 can provide braking force in response to either or both of an electrical signal and / or hydraulic brake pressure supply. Alternatively or additionally, two front wheel brake units 22c, 22d of the wheel brake units 22a, 22b, 22c, 22d can be configured with EPB calipers 56. In some embodiments, each of the ESC modules 52, 54 can be configured to control one or more of the EPB calipers 56. For example, the ECU in module 52 may control one of the two EPB calipers 56 in the right rear wheel brake unit 22 c, and the ECU in module 54 may control the other EPB caliper 56 in the left rear wheel brake unit 22 d. This configuration may provide enhanced safety and / or redundancy in the event of an ECU failure.

[0023] Figure 3 A schematic block diagram illustrating the functional interconnection between vehicle systems including the second brake system 50 is shown. Figure 3 The vehicle is shown including a propulsion subsystem 60 that can also provide regenerative braking. The propulsion subsystem 60 can include one or more electric machines, such as motor / generators. The propulsion subsystem 60 can include other associated equipment, such as an inverter, an electronic control unit, a battery, etc. Figure 3Also shown is an autonomous driving (AD) electronic control unit (ECU) 62, which provides an AD stack that communicates with each of the functions in the propulsion subsystem 60 and the second braking system 50. The AD ECU 62 may include hardware and / or software configured to coordinate the autonomous driving functions of the vehicle. The AD ECU 62 may be responsible for both propulsion and braking. The AD ECU 62 may control regenerative braking, which may include a majority of braking above a predetermined speed. Below the predetermined speed, the ECUs 80 and 180 of the ESC modules 52 and 54 of the second braking system 50 may control braking to a stop.

[0024] The ESC module 52 and the PSU module 54 of the second braking system 50 may be driven to decelerate the vehicle or bring the vehicle to a standstill, and may function as follows:

[0025] The ESC module 52 and the PSU module 54 each include a corresponding brake modulator. Any one or two of the brake modulators can apply the wheel brake parts 22a, 22b, 22c, 22d to provide redundant braking. The brake modulator may include a pump to provide brake fluid for applying the wheel brake parts 22a, 22b, 22c, 22d. The ESC module 52 and the PSU module 54 can alternate the brake part application tasks to balance the wear between them. In some embodiments, automatic emergency braking (AEB), anti-lock braking (ABS), dynamic rear brake proportion (DRP) for maintaining front and rear braking balance, and / or electronic stability control (ESC) functions can be handled by the ESC module 52 or the PSU module 56. The operating time of the pumps in the ESC module 52 and the PSU module 54 can be recorded and reported for maintenance.

[0026] Figure 4 1 shows a schematic block diagram illustrating the hydraulic interconnection of the second brake system 50. Figure 4 As shown, each of the wheel brakes 22a, 22b, 22c, 22d is connected to a corresponding wheel 23a-23d to apply braking force thereto. A fluid reservoir 58 is connected to the PSU module 54 for supplying brake fluid thereto.

[0027] Also like Figure 6 As shown, each of the rear wheel brake units 22c and 22d includes an electric parking brake unit (EPB). The electric parking brake unit (EPB) of the right rear wheel brake unit 22c is electrically connected to the second brake unit ECU 180, and the electric parking brake unit (EPB) of the left rear wheel brake unit 22d is electrically connected to the first brake unit ECU 80. This arrangement provides redundancy for the electric parking brake unit (EPB) in the event that either brake unit ECU 80 or 180 loses power or is otherwise unavailable.

[0028] Figure 5 Schematic block diagram showing the electrical interconnection of the second brake system 50 is shown. Figure 5 As shown, each of the wheels 23a-23d is connected to a corresponding wheel speed sensor 70a-70d for measuring the rotational speed of the wheel. The front wheel speed sensors 70a, 70b are connected to the first brake unit ECU 80. The rear wheel speed sensors 70c, 70d are connected to the second brake unit ECU 180. In the event that any of the brake unit ECUs 80, 180 loses power or is otherwise unavailable, this arrangement provides redundancy for the wheel speed sensors 70a, 70b and 70c, 70d. Both the first brake ECU 80 and the second brake ECU 180 are functionally connected to the AD ECU 62. A first power source (such as a first battery 72) is connected to the ESC module 52 to provide backup power to the ESC module 52, and a second power source (such as a second battery 74) is connected to the PSU module 54 to provide backup power thereto. In this way, the ESC module 52 and the PSU module 54 each have separate and independent backup power sources.

[0029] Figure 6 A schematic diagram of a second braking system 50 is shown, showing details of each of the ESC module 52 and the PSU module 54 and their interconnections. Each of the modules has two separate and independent brake circuits, with associated components designated as primary and secondary. The separate and independent brake circuits can each operate under normal conditions and can provide redundancy. For example, even in the event of a major failure of the other brake circuit (such as a large fluid leak), either brake circuit can still provide braking function.

[0030] like Figure 6 As shown, the ESC module 52 includes a first primary interconnecting channel 76 having a corresponding primary inlet port 77 and a first secondary interconnecting channel 78 having a corresponding secondary inlet port 79. The ESC module 52 also includes a first brake ECU 80 and a first pump 82 having a first motor 84 controlled by the first brake ECU 80. For example, the first brake ECU 80 can supply control power, such as pulse-width modulated (PWM) AC power, to the first motor 84 for controlling the speed of the first motor 84. The first pump 82 also includes a first primary pump element 85 and a first secondary pump element 86, each coupled to the first motor 84 for supplying fluid through a corresponding brake circuit. The steering angle sensor 64 is in functional communication with the first brake ECU 80 to transmit steering angle data to the first brake ECU 80. The first brake ECU 80 can use the steering angle data and / or other vehicle data to adjust one or more parameters related to the operation of the brake component.

[0031] The ESC module 52 includes a main supply fluid passage 88 configured to transfer fluid from the first main pump element 85 of the first pump 82 to two of the wheel brake components 22a, 22b. The ESC module 52 also includes an auxiliary supply fluid passage 89 configured to transfer fluid from the first auxiliary pump element 86 of the first pump 82 to the other two of the wheel brake components 22c, 22d. The ESC module 52 includes a main return fluid passage 90 configured to transfer fluid from the corresponding wheel brake components 22a, 22b to the first main pump element 85 of the first pump 82. The ESC module 52 also includes an auxiliary return fluid passage 91 configured to transfer fluid from the corresponding wheel brake components 22c, 22d to the first auxiliary pump element 86 of the first pump 82.

[0032] An accumulator 92 is coupled to each of the return fluid passages 90 and 91 for holding fluid from the corresponding wheel brake portion 22a, 22b, 22c, and 22d and supplying the fluid to the corresponding pump element 85 or 86. Each accumulator 92 may include a piston that is displaceable within a bore and is spring-biased to retain fluid therein. However, either or both accumulators 92 may have a different configuration. A return check valve 93 is disposed between each of the return fluid passages 90 and 91 and the corresponding one of the first pump elements 85 or 86 to allow fluid to flow from the return fluid passages 90 and 91 to the corresponding one of the first pump elements 85 or 86 while preventing fluid from flowing in the opposite direction.

[0033] The ESC module 52 also includes a first muffler 94 disposed between the outlet of each first pump element 85, 86 and the corresponding supply fluid passage 88, 89. Each of the first mufflers 94 includes a restrictor orifice connected to the outlet of the corresponding first pump element 85, 86, and a drain valve in parallel with the restrictor orifice to allow flow restriction under low hydraulic flow conditions and unrestricted hydraulic flow under high flow restriction. The ESC module 52 also includes an elastomeric damper 95 connected to the outlet of each first pump element 85, 86 to reduce pulsation in the pressure of the fluid supplied therefrom and further reduce noise.

[0034] The ESC module 52 includes an apply valve 96a and a release valve 96b associated with each wheel brake 22a, 22b, 22c, 22d to control the flow of fluid into and out of the wheel brake 22a, 22b, 22c, 22d. The apply valve 96a is configured to control the flow of fluid from a corresponding one of the supply fluid passages 88, 89 to a corresponding one of the wheel brakes 22a, 22b, 22c, 22d. The release valve 96b is configured to control the flow of fluid from a corresponding one of the wheel brakes 22a, 22b, 22c, 22d to a corresponding one of the supply fluid passages 88, 89 and to a corresponding one of the return fluid passages 96, 91.

[0035] The ESC module 52 also includes a primary priming valve 100 configured to selectively control fluid communication between the first primary interconnecting passage 76 and the inlet of the first main pump element 85 of the first pump 82. The ESC module 52 also includes an auxiliary priming valve 102 configured to selectively control fluid communication between the first auxiliary interconnecting passage 78 and the inlet of the first auxiliary pump element 86 of the first pump 82. Each priming valve 100, 102 may be a normally closed solenoid valve.

[0036] The ESC module 52 also includes a first main pressure control valve 104 hydraulically connected between the first main interconnect passage 76 and the main supply fluid passage 88 for regulating the fluid pressure in the first main interconnect passage 76. The ESC module 52 also includes a first auxiliary pressure control valve 106 hydraulically connected between the first auxiliary interconnect passage 78 and the auxiliary supply fluid passage 89 for regulating the fluid pressure in the first auxiliary interconnect passage 78. Each of the first pressure control valves 104, 106 may be a normally open linear isolation valve capable of variably controlling the pressure across the valve. The ESC module 52 also includes a first pressure sensor 108 configured to monitor the fluid pressure in the first main interconnect passage 76 and connected to the first brake ECU 80 to transmit the measured pressure to the first brake ECU 80.

[0037] like Figure 6As shown, the PSU module 54 includes a second primary interconnecting channel 176 having a corresponding primary outlet port 177, which is fluidically coupled to the primary inlet port 77 of the ESC module 52 for supplying fluid thereto. The PSU module 54 also includes a second secondary interconnecting channel 178 having a corresponding secondary outlet port 179, which is fluidically coupled to the secondary inlet port 79 of the PSU module 54 for supplying fluid thereto. The PSU module 54 also includes a second brake ECU 180 and a second pump 182 having a second motor 184 controlled by the second brake ECU 180. For example, the second brake ECU 180 can supply control power, such as pulse-width modulated (PWM) AC power, to the second motor 184 for controlling the speed of the second motor 184. The second pump 182 also includes a second primary pump element 185 and a second secondary pump element 186, each of which is coupled to the second motor 184 for supplying fluid through a corresponding brake circuit. The second primary pump element 185 is configured to transfer brake fluid from the fluid reservoir 58 to the first primary interconnection channel 76 of the ESC module 52 via the second primary interconnection channel 176. The second secondary pump element 186 is configured to transfer brake fluid from the fluid reservoir 58 to the first secondary interconnection channel 78 of the ESC module 52 via the second secondary interconnection channel 178.

[0038] The PSU module 54 includes a primary reservoir fluid passage 188 configured to deliver fluid from the fluid reservoir 58 to the second primary pump element 185 of the second pump 182 via the primary reservoir port Rp. The PSU module 54 also includes a secondary reservoir fluid passage 189 configured to deliver fluid from the fluid reservoir 58 to the second secondary pump element 186 of the second pump 182 via the secondary reservoir port Rs. The PSU module 54 includes a primary bypass fluid passage 190 that provides fluid communication between the primary reservoir fluid passage 188 and the second primary interconnect passage 176 to deliver brake fluid directly from the fluid reservoir 58 to the ESC module 52 and bypass the second pump 182. The PSU module 54 includes a secondary bypass fluid channel 191 that provides fluid communication between the secondary reservoir fluid channel 189 and the second secondary interconnect channel 178 to directly deliver brake fluid from the fluid reservoir 58 to the ESC module 52, bypassing the second pump 182. An inline check valve 193 is located in the fluid path between each of the second interconnect channels 176, 178 and a corresponding one of the bypass fluid channels 190, 191. Each of the inline check valves 193 is configured to allow fluid to flow from the fluid reservoir 58 through the corresponding one of the bypass fluid channels 190, 191 and to the ESC module 52 via the corresponding one of the second interconnect channels 176, 178, while preventing fluid flow in the opposite direction. Each of the inline check valves 193 can have a low discharge pressure, thereby allowing fluid to flow through the inline check valve 193 only when a predetermined fluid pressure exists across the inline check valve 193, which can be a relatively low pressure.

[0039] An accumulator 192, which may be formed as a cavity in the body of the PSU module 54, is coupled to each of the second pump elements 185, 186 of the second pump 182. The PSU module 54 also includes a second muffler 194 disposed between the outlet of each of the second pump elements 185, 186 and a corresponding one of the second interconnecting channels 176, 178. Each of the second mufflers 194 includes a restrictor orifice connected to the outlet of the corresponding one of the second pump elements 185, 186, and a discharge valve in parallel with the restrictor orifice to allow flow restriction under low hydraulic flow conditions and unrestricted hydraulic flow under high flow restriction. The PSU module 54 also includes a second elastomeric damper 195 connected to the outlet of each of the second pump elements 185, 186 of the second pump 182 to reduce pulsation of the pressure of the fluid supplied therefrom and further reduce noise.

[0040] The PSU module 54 also includes a second main pressure control valve 152 that controls fluid flow between the second main interconnect passage 176 and the main bypass fluid passage 190. The second brake ECU 180 can provide a control signal to the second main pressure control valve 152 to regulate fluid pressure in the first main interconnect passage 76. The PSU module 54 also includes a second auxiliary pressure control valve 154 that controls fluid flow between the second auxiliary interconnect passage 178 and the auxiliary bypass fluid passage 191. The second brake ECU 180 can provide a control signal to the second main pressure control valve 152 to regulate fluid pressure in the second auxiliary interconnect passage 178, and thereby also regulate fluid pressure in the first auxiliary interconnect passage 78 of the ESC module 52. Each of the second pressure control valves 152, 154 can be a normally open linear isolation valve capable of variably controlling flow through and / or pressure across the normally open linear isolation valve.

[0041] The PSU module 54 also includes a second pressure sensor 160 configured to monitor fluid pressure in the second auxiliary interconnection channel 178 and connected to the second brake ECU 180 to transmit the measured pressure to the second brake ECU 180 .

[0042] Also like Figure 6 As shown, each of the rear wheel brake units 22c and 22d includes an electric parking brake (EPB). The EPB of the right rear wheel brake unit 22c is electrically connected to the second brake unit ECU 180, and the EPB of the left rear wheel brake unit 22d is electrically connected to the first brake unit ECU 80. This arrangement provides redundancy for the EPB in the event that either brake ECU 80 or 180 loses power or is otherwise unavailable. Alternatively or additionally, the front wheel brake units 22a and 22b may include an electric parking brake (EPB).

[0043] Figure 7A schematic diagram of a third brake system 150 is shown. Third brake system 150 may be similar or identical to second brake system 50, but with the addition of isolation valves 156 and 158 in PSU module 54 to further improve flow control of second pump 182. The isolation valves 156 and 158 include a primary isolation valve 156 configured to control fluid flow between the outlet of a second main pump element 185 and the second main interconnecting passage 176. The isolation valves 156 and 158 also include an auxiliary isolation valve 158 configured to control fluid flow between the outlet of a second auxiliary pump element 186 and the second auxiliary interconnecting passage 178. Each isolation valve 156 and 158 may be a normally open linear isolation valve capable of variably controlling flow through the valve. The second brake ECU 180 may supply a control signal to each of the isolation valves 156 and 158 to provide additional flow control.

[0044] According to one aspect of the present disclosure, a braking system for a motor vehicle is provided. The braking system can be activated to decelerate the vehicle in a normal brake-by-wire operating mode by an autopilot / autonomous driving device (AD ECU) controlling a primary electronic stability control component (ESC), and the same braking system can be activated to decelerate the vehicle in a fail-back mode with a faulty ESC component by an autopilot / autonomous driving device controlling a secondary pressure supply unit (PSU).

[0045] The present invention provides a braking system for a motor vehicle. The braking system includes an electronic stability control (ESC) module and a pressure supply unit (PSU) module, wherein the ESC module defines a first interconnected channel and the PSU module defines a second interconnected channel in fluid communication with the first interconnected channel of the ESC module. The ESC module includes a first pump configured to transfer brake fluid from the PSU module and transfer the brake fluid to a plurality of wheel brake units, and a priming valve configured to selectively control the fluid communication between the first interconnected channel and the inlet of the first pump. The PSU module includes a second pump configured to transfer brake fluid from a fluid reservoir to the first interconnected channel of the ESC module, and a bypass fluid channel having a straight-through check valve. The bypass fluid channel is configured to transfer the brake fluid directly from the fluid reservoir to the ESC module and bypass the second pump. The straight-through check valve is configured to allow fluid to flow from the fluid reservoir through the bypass fluid channel and to the ESC module, while preventing fluid from flowing in the opposite direction.

[0046] In some embodiments, each of the ESC module and the PSU module includes two separate and independent brake circuits, wherein each of the first pump and the second pump includes a primary pump element and a secondary pump element for pumping brake fluid through a corresponding one of the brake circuits.

[0047] In some embodiments, the priming valve is a normally closed solenoid valve.

[0048] In some embodiments, the ESC module further includes: a supply fluid channel configured to deliver the brake fluid from the first pump to at least one wheel brake portion among the plurality of wheel brake portions; and at least one of an apply valve and a release valve for controlling fluid flow between the supply fluid channel and the at least one wheel brake portion.

[0049] In some embodiments, the ESC module further includes a pressure control valve configured to control fluid flow between the first interconnection channel and the supply fluid channel of the ESC module to regulate fluid pressure.

[0050] In some embodiments, the pressure control valve is a normally open linear valve capable of variably controlling flow through the pressure control valve.

[0051] In some embodiments, the PSU module further includes a pressure control valve that controls fluid flow between the second interconnection channel and the bypass fluid channel to adjust fluid pressure.

[0052] In some embodiments, the pressure control valve is a normally open linear isolation valve.

[0053] In some embodiments, the PSU module further comprises an isolation valve that controls fluid flow between the outlet of the second pump and the second interconnection channel.

[0054] In some embodiments, the isolation valve is a normally open linear valve capable of variably controlling flow through the isolation valve.

[0055] In some embodiments, each of the ESC module and the PSU module has an associated brake electronic control unit (ECU), each of the brake ECUs is separate and independent, and each of the brake ECUs has a corresponding power supply that is separate and independent from each other.

[0056] The present invention also provides a braking system for a motor vehicle. The braking system includes an electronic stability control (ESC) module and a PSU module, the ESC module defining a first interconnected channel, and the PSU module defining a second interconnected channel in fluid communication with the first interconnected channel of the ESC module. The ESC module includes a first electronic control unit (ECU) and a first pump, the first pump being configured to transfer brake fluid from the PSU module and to transfer the brake fluid to a plurality of wheel brake portions. The PSU module includes a second ECU and a second pump configured to transfer the brake fluid from a fluid storage portion to the first interconnected channel of the ESC module, and a bypass fluid channel having a straight-through check valve. The bypass fluid channel is configured to deliver the brake fluid directly from the fluid storage portion to the ESC module and bypass the second pump. The straight-through check valve is configured to allow fluid to flow from the fluid storage portion through the bypass fluid channel and to the ESC module, while preventing fluid from flowing in the opposite direction.

[0057] In some embodiments, the braking system is configured to alternately apply the plurality of wheel brakes between the ESC module and the PSU module.

[0058] In some embodiments, the ESC module further includes an isolation valve configured to selectively control fluid communication between the first interconnect channel and an inlet of the first pump.

[0059] In some embodiments, the isolation valve is a normally open solenoid valve.

[0060] In some embodiments, the first ECU is configured to control operation of the first pump, and the second ECU is configured to control operation of the second pump, and the braking system further includes an autonomous driving (AD) ECU in communication with each of the first ECU and the second ECU.

[0061] In some embodiments, the AD ECU is configured to use linearly controlled regenerative braking for a braking event if the motor vehicle is travelling at a speed greater than a given speed.

[0062] In some embodiments, the AD ECU is configured to activate one of the first pump or the second pump to supply the brake fluid to the plurality of wheel braking portions for a braking event if the motor vehicle is traveling at a speed lower than a given speed.

[0063] In some embodiments, the AD ECU is configured to, in response to detecting a fault condition in the ESC module, command the second ECU of the PSU module to supply the brake fluid to the plurality of wheel braking portions for a braking event.

[0064] In some embodiments, at least one of the first ECU or the second ECU is configured to implement at least one of an anti-lock braking system (ABS), automatic emergency braking (AEB), and electronic stability control (ESC) based on at least one of a detected surface condition and a command from an autonomous driving (AD) ECU.

[0065] In some embodiments, to save manufacturing costs, the ESC module and the PSU module can be housed in a module with the same appearance.

[0066] Obviously, in light of the above teachings, many modifications and variations of the present invention are possible, and these modifications and variations can be implemented in ways other than those specifically described, while remaining within the scope of the appended claims. These preceding statements should be understood to cover any combination of novel practices of the present invention that are practical.

[0067] This patent application claims the benefit of U.S. Provisional Patent Application No. 63 / 285,478, filed on December 2, 2021, the contents of which are incorporated herein by reference in their entirety.

Claims

1. A braking system for a motor vehicle, the braking system comprising: an electronic stability control module and a pressure supply unit module, the electronic stability control module defining a first interconnect passage, the pressure supply unit module defining a second interconnect passage in fluid communication with the first interconnect passage of the electronic stability control module; The electronic stability control module includes a first pump configured to transfer brake fluid from the pressure supply unit module and to transfer the brake fluid to a plurality of wheel brake portions, and a priming valve configured to selectively control fluid communication between the first interconnection passage and an inlet of the first pump; The pressure supply unit module includes a second pump configured to transfer the brake fluid from a fluid reservoir to the first interconnection channel of the electronic stability control module, and a bypass fluid channel having a through-check valve; wherein the bypass fluid passage is configured to deliver the brake fluid directly from the fluid reservoir to the electronic stability control module and bypass the second pump; and wherein the through check valve is configured to allow fluid to flow from the fluid reservoir through the bypass fluid passage and to the electronic stability control module while preventing fluid from flowing in the opposite direction, The pressure supply unit module further includes a pressure control valve, which controls the fluid flow between the second interconnected channel and the bypass fluid channel to adjust the fluid pressure. The pressure supply unit module further includes an isolation valve that controls fluid flow between the outlet of the second pump and the second interconnection channel, wherein the isolation valve is a normally open linear valve capable of variably controlling a flow rate through the isolation valve.

2. The braking system according to claim 1, wherein: Each of the electronic stability control module and the pressure supply unit module includes two separate and independent brake circuits, wherein each of the first pump and the second pump includes a primary pump element and a secondary pump element for pumping brake fluid through a corresponding one of the brake circuits.

3. The braking system according to claim 1, wherein: The starting valve is a normally closed solenoid valve.

4. The braking system according to claim 1, wherein: The electronic stability control module further includes: a supply fluid channel configured to deliver the brake fluid from the first pump to at least one wheel brake of the plurality of wheel brakes; and at least one of an apply valve and a release valve for controlling fluid flow between the supply fluid channel and the at least one wheel brake.

5. The braking system according to claim 4, wherein: The electronic stability control module further includes a pressure control valve configured to control fluid flow between the first interconnection passage and the supply fluid passage of the electronic stability control module to regulate fluid pressure.

6. The braking system according to claim 5, wherein: The pressure control valve is a normally open linear valve capable of variably controlling a flow rate through the pressure control valve.

7. The braking system according to claim 1, wherein: The pressure control valve is a normally open linear isolation valve.

8. The braking system according to claim 1, wherein: Each of the electronic stability control module and the pressure supply unit module has an associated brake electronic control unit, each of the brake electronic control units being separate and independent, and Each of the brake electronic control units has a corresponding power supply, and the power supplies are separate and independent from each other.

9. A braking system for a motor vehicle, the braking system comprising: an electronic stability control module and a pressure supply unit module, the electronic stability control module defining a first interconnect passage, the pressure supply unit module defining a second interconnect passage in fluid communication with the first interconnect passage of the electronic stability control module; The electronic stability control module includes a first electronic control unit and a first pump configured to transfer brake fluid from the pressure supply unit module and transfer the brake fluid to a plurality of wheel braking portions; The pressure supply unit module includes a second electronic control unit and a second pump configured to transfer the brake fluid from a fluid reservoir to the first interconnection channel of the electronic stability control module, and a bypass fluid channel having a through-check valve; wherein the bypass fluid passage is configured to deliver the brake fluid directly from the fluid reservoir to the electronic stability control module and bypass the second pump; and wherein the through check valve is configured to allow fluid to flow from the fluid reservoir through the bypass fluid passage and to the electronic stability control module while preventing fluid from flowing in the opposite direction, The pressure supply unit module further includes a pressure control valve, which controls the fluid flow between the second interconnected channel and the bypass fluid channel to adjust the fluid pressure. The pressure supply unit module further includes an isolation valve that controls fluid flow between the outlet of the second pump and the second interconnection channel, wherein the isolation valve is a normally open linear valve capable of variably controlling a flow rate through the isolation valve.

10. The braking system according to claim 9, wherein: The brake system is configured to apply the plurality of wheel brakes alternately between the electronic stability control module and the pressure supply unit module.

11. The braking system according to claim 9, wherein: The first electronic control unit is configured to control the operation of the first pump, and the second electronic control unit is configured to control the operation of the second pump, and Wherein, the braking system further includes an automatic driving electronic control unit communicating with each of the first electronic control unit and the second electronic control unit.

12. The braking system according to claim 11, wherein: The autonomous driving electronic control unit is configured to use linearly controlled regenerative braking for a braking event if the motor vehicle is travelling at a speed greater than a given speed.

13. The braking system according to claim 11, wherein: The automatic driving electronic control unit is configured to activate one of the first pump or the second pump to supply the brake fluid to the plurality of wheel braking portions for a braking event when the motor vehicle is traveling at a speed lower than a given speed.

14. The braking system according to claim 11, wherein: The autonomous driving electronic control unit is configured to command the second electronic control unit of the pressure supply unit module to supply the brake fluid to the plurality of wheel braking portions for a braking event in response to detecting a fault condition in the electronic stability control module.

15. The braking system according to claim 9, wherein: At least one of the first electronic control unit or the second electronic control unit is configured to implement at least one of an anti-lock braking system, dynamic rear pressure (DRP) control of front and rear brake balancing, automatic emergency braking, and electronic stability control based on at least one of a detected surface condition and a command from an autonomous driving electronic control unit.

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