Brake signal simulator and redundant control system for electromechanical brake systems

Abstract

The application discloses a brake signal simulator and a redundant control system for an electromechanical brake system; the brake signal simulator comprises a shell, a primary compression module, a secondary compression module and a signal detection module; the primary compression module comprises a first top rod and a first elastic component; the secondary compression module comprises a second top rod and a second elastic component; the signal detection module comprises a stroke detector and a pressure sensor; the stroke detector is installed in the shell and is used for detecting the movement stroke of the first top rod and outputting a stroke signal of the first top rod; the pressure sensor is arranged at the bottom of the shell and is used for detecting the resultant force of the pressures of the first top rod and the second top rod and outputting a pressure signal. The brake signal simulator adopts a redundant control strategy, and the main control signal and the redundant control signal are used for jointly and coordinately controlling the EMB system to execute a brake instruction, so that the driving safety of the vehicle is ensured.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of vehicle braking, and particularly relates to a brake signal simulator and a redundant control system for an electronic mechanical braking system. BACKGROUND

[0002] An electronic mechanical braking system (EMB) is an important component of a vehicle drive-by-wire system. A typical electronic mechanical braking system uses electrical energy as the energy source. The driver's braking intention is input to the electronic mechanical braking system through an electrical signal generated by a brake pedal unit, to control an EMB actuator arranged at the wheel edge of the vehicle to generate a braking force in accordance with the driver's braking intention, thereby implementing braking on the vehicle. Since the brake pedal unit of the electronic mechanical braking system is only connected to the electronic brake device at the wheel edge through a signal cable, it cannot generate a tactile feedback similar to that of a hydraulic or pneumatic braking system to the driver. Therefore, a pedal unit capable of simulating the nonlinear feedback force of a traditional brake pedal is needed, so that the driver does not need to adapt to the control of the electronic mechanical braking system.

[0003] Therefore, the invention patent application with the application publication number CN112849106A discloses a "brake pedal feeling simulator and braking system". The brake pedal feeling simulator includes a housing, a limiting mechanism fixed relative to the housing, a primary compression mechanism and a secondary compression mechanism installed in the housing. The primary compression mechanism includes a primary top rod, a pre-tightening piece, and a first and a second helical spring arranged in parallel. The working principle is as follows: when there is no pedal operation, the primary top rod is axially limited by the limiting mechanism, or the primary top rod and the pre-tightening piece are axially limited by the limiting mechanism, the first helical spring is pre-tightened by the primary top rod and the secondary compression mechanism, and the second helical spring is pre-tightened by the pre-tightening piece and the secondary compression mechanism. The primary top rod directly or indirectly starts to compress the first and second helical springs in sequence in response to pedal operation. The operating force from the top rod is shared by the first and second helical springs, i.e., the sum of the elastic forces generated by the first and second helical springs is equal to the operating force from the top rod. When braking is implemented, the primary compression mechanism first compresses one of the first and second helical springs, and then starts to compress the other one. Through segmented compression of the parallel compound spring structure, a nonlinear and gradually changing feedback force is generated, thereby simulating the brake pedal feeling of a traditional braking system.

[0004] It is worth noting that the above-mentioned brake pedal feeling simulator can realize the simulation of brake pedal feeling, but does not propose a detection signal redundancy structure scheme, so that after the stroke detection signal in the brake pedal feeling simulator fails, no redundant brake signal (a brake signal different from the original signal) is provided to the EMB brake execution module, so that the vehicle cannot be effectively braked. As is known, in the traditional hydraulic brake system, the simulator signal loss can also realize forced braking through the mechanical execution mechanism, and in the fully line-controlled brake EMB system, if the pedal simulator signal loss occurs, the EMB will lose the brake function, which will exist a major safety hazard. In addition, since the brake pedal feeling simulator does not set a signal checking module, the original signal cannot be checked, so that it cannot be guaranteed that the brake signal output by the brake pedal feeling simulator is the actual required brake signal, so that the vehicle brake safety exists hidden dangers. Therefore, with the rapid development and industrial application of the fully line-controlled EMB brake system, the development of the pedal feeling simulator with signal redundancy function is imminent. SUMMARY

[0005] In order to solve the problems existing in the prior art, the application innovatively provides a brake signal simulator for an electronic mechanical brake system, which adopts a redundant signal control strategy, and executes a brake instruction through a main control signal and a redundant control signal to cooperate with the electronic mechanical brake system, thereby ensuring the safety of vehicle braking.

[0006] The second object of the application is to provide a redundant control system adopting the above-mentioned brake signal simulator.

[0007] The technical scheme for solving the above-mentioned technical problems of the application is:

[0008] A brake signal simulator, comprising a shell, a first compression module, a second compression module and a signal detection module for detecting the size of the brake force, which are arranged in the shell, wherein,

[0009] The first compression module is located above the second compression module;

[0010] The first compression module comprises a first top rod and a first elastic component arranged at the lower end of the first top rod, wherein the upper end of the first top rod is connected with a brake pedal, and the first top rod is installed in the shell through a first sliding connection structure; the first sliding connection structure is used to promote the movement of the first top rod along the axial direction thereof;

[0011] The secondary compression module comprises a second top rod and a second elastic assembly arranged at the lower end of the second top rod, wherein the axis direction of the second top rod coincides with the axis direction of the first top rod, and the second top rod is installed in the shell through a second sliding connection structure; the second sliding connection structure is used to facilitate the movement of the second top rod along its axis direction;

[0012] The signal detection module comprises a stroke detector and a pressure sensor, wherein the stroke detector is installed in the shell, is used to detect the movement stroke of the first top rod, and outputs a stroke signal; the pressure sensor is arranged at the bottom of the shell, is used to detect the resultant force of the pressure of the first top rod and the second top rod, and outputs a pressure signal.

[0013] In a preferred scheme of the present application, the first elastic assembly comprises a first spring seat and a first spring arranged on the first spring seat, wherein the first spring seat is arranged at the bottom of the first top rod; the bottom of the first top rod is connected with a nut after penetrating through the first spring seat; a guide hole is arranged on the first spring seat at a position corresponding to the first top rod; a bushing matched with the first top rod is arranged on the inner wall of the guide hole; the outer diameter of the nut is larger than the inner diameter of the guide hole; the first spring is sleeved on the first top rod, the upper end of the first spring acts on the first top rod, and the lower end acts on the first spring seat.

[0014] The second elastic assembly comprises a second spring seat and a second spring arranged on the second spring seat, wherein the second top rod is provided with a first accommodating cavity at a position corresponding to the first spring seat; the second spring seat is arranged at the bottom of the second top rod; the second spring is sleeved on the outer side of the second spring seat, the upper end of the second spring acts on the second top rod, and the lower end acts on the second spring seat.

[0015] In a preferred scheme of the present application, the bottom of the second top rod is provided with a buffer spring, and the buffer spring is a rubber spring; the second spring seat is provided with an accommodating groove for accommodating the buffer spring.

[0016] In a preferred scheme of the present application, the upper end of the shell is provided with an end cover, the end cover is installed on the shell, and a first sealing assembly is arranged between the shell and the end cover; the end cover is provided with a through hole, the upper end of the first top rod is connected with the brake pedal after penetrating through the through hole; a second sealing assembly is arranged between the upper end of the first top rod and the through hole, and the second sealing assembly is installed on the first top rod.

[0017] In a preferred scheme of the present application, a limiting portion is arranged at the middle of the first top rod, the outer diameter of the limiting portion is greater than the inner diameter of the through hole on the end cover, and a mounting groove is arranged on the limiting portion, and the detection end of the stroke detector is mounted in the mounting groove.

[0018] In a preferred scheme of the present application, the stroke detector includes, but is not limited to, a potentiometer or / and a Hall sensor.

[0019] A redundant control system includes the brake signal simulator, the signal verification module and the fault alarm module, wherein,

[0020] The brake signal simulator is used to output a stroke signal and a pressure signal according to the pedal stroke of the driver stepping on the brake pedal, and transmit the stroke signal and the pressure signal to the signal verification module;

[0021] The signal verification module includes a stroke signal comparative analysis module, a signal selection module and a stroke calculation module, wherein,

[0022] The stroke signal comparative analysis module compares and analyzes the measured value and the theoretically calculated value of the stroke signal, sends the comparative analysis result to the signal selection module, and sends a fault signal to the fault alarm module;

[0023] The signal selection module selects the corresponding stroke signal or pressure signal according to the signal comparison result and sends it to the stroke calculation module;

[0024] The stroke calculation module is used to calculate the brake stroke according to the stroke signal or the pressure signal, compare the brake stroke with the idle stroke of the brake signal simulator, if the brake stroke is greater than the idle stroke, send the brake stroke to the EMB system controller, the EMB system controller sends a control instruction to the EMB actuator to perform brake response, and if the brake stroke is less than or equal to the idle stroke, the brake stroke is not sent to the EMB system controller.

[0025] In a preferred scheme of the present application, the obtained stroke signal includes a first potential signal and a second potential signal, the sum of the first potential signal and the second potential signal is equal to a fixed value, and the signal comparative analysis module compares and analyzes the measured value and the theoretically calculated value of the first potential signal, the second potential signal and the pressure signal according to the following steps:

[0026] Step S1: obtaining the theoretically calculated value of the first potential signal, the theoretically calculated value of the second potential signal, and the theoretically calculated value of the sum of the first potential signal and the second potential signal;

[0027] Step S2: judging whether the first difference between the sum of the first potential signal and the second potential signal and the theoretically calculated value of the sum is within a first error range.

[0028] If the first difference is within the first error range, it indicates that the stroke detector is in normal working state, and the optimal solution between the first potential signal and the second potential signal output by the stroke detector is used to calculate the brake stroke as the brake signal.

[0029] If the first difference is not within the first error range, it indicates that the stroke detector is in abnormal working state, and the brake stroke is calculated according to the pressure signal as the brake signal, and a fault signal is sent to the fault alarm module.

[0030] In a preferred embodiment of the present application, in step S2, the step of obtaining the optimal solution between the first potential signal and the second potential signal is:

[0031] The measured value and the theoretically calculated value of the first potential signal and the second potential signal are checked and compared, and it is judged whether the second difference between the measured value and the theoretically calculated value of the first potential signal and the third difference between the measured value and the theoretically calculated value of the second potential signal are within the second error range;

[0032] If the second difference and the third difference are within the second error range, the first potential signal is used to calculate the brake stroke as the brake signal.

[0033] If the second difference is not within the second error range, but the third difference is within the second error range, the second potential signal is used to calculate the brake stroke as the brake signal.

[0034] If the second difference and the third difference are not within the second error range, the brake stroke is calculated according to the pressure signal as the brake signal, and a fault signal is sent to the fault alarm module.

[0035] A redundant control system comprises the brake signal simulator, the first stroke calculation module, the stroke checking module, the second stroke calculation module, the signal comparison module, the signal sending module and the fault alarm module, wherein,

[0036] The signal detection module in the brake signal simulator comprises a potentiometer or / and a Hall sensor for detecting the stroke of the first top rod and a pressure sensor for detecting the total pressure of the brake pedal, wherein the potentiometer or / and the Hall sensor outputs a stroke signal to the first stroke calculation module; the stroke signal comprises a first potential signal and a second potential signal; the pressure sensor outputs a pressure signal to the first stroke calculation module;

[0037] The first stroke calculation module calculates the pedal stroke stepped by the driver according to the first potential signal, the second potential signal output by the stroke detector and the pressure signal output by the pressure sensor respectively, and outputs the first pedal stroke signal, the second pedal stroke signal and the third pedal stroke signal respectively, and sends the first pedal stroke signal, the second pedal stroke signal and the third pedal stroke signal to the stroke verification module;

[0038] The stroke verification module analyzes whether the first pedal stroke signal, the second pedal stroke signal and the third pedal stroke signal are abnormal, and sends the pedal stroke signal with the abnormality to the fault alarm module, and the fault alarm module alarms; the stroke verification module sends all the normal pedal stroke signals to the second stroke calculation module;

[0039] The second stroke calculation module calculates the stroke average value of the received normal pedal stroke signals, and sends the stroke average value to the signal comparison module;

[0040] The signal comparison module is used to judge whether the calculated stroke average value is greater than the idle stroke of the brake signal simulator;

[0041] If the stroke average value is greater than the idle stroke of the brake signal simulator, the signal sending module sends the stroke average value to the EMB controller; the EMB system controller generates a brake instruction according to the stroke average value and sends it to the EMB actuator to perform brake response;

[0042] If the stroke average value is less than or equal to the idle stroke of the brake signal simulator, the signal sending module does not send the stroke average value to the EMB controller.

[0043] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0044] 1. The present application innovatively proposes a brake signal simulator for an electronic mechanical brake system based on double redundant signals, which detects the pedal stroke stepped by the driver through a stroke detector with two signals as a stroke signal, and detects the pressure of the pedal stepped by the driver through a pressure sensor and calculates the pedal stroke according to the pedal pressure signal as a pressure signal. By comparing and selecting the stroke signal or the pressure signal, a brake instruction conforming to the driver's braking intention is generated and sent to the EMB brake controller; the brake signal simulator proposed by the present application has high safety in the fully linear EMB system, and can effectively solve the serious problem that the EMB brake system fails due to the lack of redundant control signals in the brake signal simulator of the fully linear EMB system.

[0045] 2、The brake signal simulator provided by the application has the characteristics of high safety, high reliability, simple structure, mature technology, low production cost, great engineering significance and industrialization vision compared with the existing brake signal simulator.

[0046] 3、The two kinds of redundant control systems provided by the application can realize mutual checking of the first potential signal, the second potential signal and the pressure signal, so as to discover the invalid signal in time and transmit it to the fault alarm module; meanwhile, the optimal signal can be selected from all effective pedal stroke signals, so as to realize the closest driver real braking intention, ensure driving safety and improve driving comfort. BRIEF DESCRIPTION OF DRAWINGS

[0047] Figure 1 and Figure 2 are sectional views of the brake signal simulator.

[0048] Figure 3 is a structural schematic view of the one-way valve.

[0049] Figure 4 is an electrical schematic diagram of the potentiometer.

[0050] Figure 5 is a SIG signal static characteristic curve diagram.

[0051] Figure 6 is a control flow chart of the first redundant signal control system of the application.

[0052] Figure 7 is a control flow chart of the second redundant signal control system of the application. DETAILED DESCRIPTION

[0053] The application will be further described in detail below in combination with the embodiments and drawings, but the embodiments of the application are not limited thereto.

[0054] Embodiment 1

[0055] Referring to Figures 1-3 , the brake signal simulator comprises a shell 5, a first-stage compression module 2, a second-stage compression module 3 arranged in the shell 5 and a signal detection module for detecting the brake force; wherein,

[0056] The first-stage compression module 2 is located above the second-stage compression module 3.

[0057] The primary compression module 2 comprises a first top rod 21 and a first elastic assembly arranged at the lower end of the first top rod 21, wherein the upper end of the first top rod 21 is connected with the brake pedal, and the first top rod 21 is installed in the shell 5 through a first sliding connection structure; the first sliding connection structure is used to facilitate the movement of the first top rod 21 along its axial direction;

[0058] The secondary compression module 3 comprises a second top rod 31 and a second elastic assembly arranged at the lower end of the second top rod 31, wherein the axial direction of the second top rod 31 coincides with the axial direction of the first top rod 21, and the second top rod 31 is installed in the shell 5 through a second sliding connection structure; the second sliding connection structure is used to facilitate the movement of the second top rod 31 along its axial direction;

[0059] The signal detection module comprises a travel detector 6 and a pressure sensor 4, wherein the potentiometer is installed in the shell 5, the detection end of the travel detector 6 is connected with the first top rod 21, and the travel detector 6 is used to detect the movement travel of the first top rod 21 and output first travel signals and second travel signals; the pressure sensor 4 is arranged at the bottom of the shell 5 and is used to detect the downward pressure of the first top rod 21 and output pressure signals.

[0060] Referring to Figures 1-3 , the first elastic assembly comprises a first spring seat 24 and a first spring 22 arranged on the first spring seat 24, wherein the first spring seat 24 is arranged at the bottom of the first top rod 21; the bottom of the first top rod 21 is connected with a nut 25 after penetrating through the first spring seat 24; the first spring seat 24 is provided with a guide hole at the corresponding position of the first top rod 21; the inner wall of the guide hole is provided with a bushing 23 matched with the first top rod 21, which is used to guide and lubricate the vertical movement of the first top rod 21; the outer diameter of the nut 25 is larger than the inner diameter of the guide hole; the first spring 22 is sleeved on the first top rod 21, and the upper end of the first spring 22 acts on the first top rod 21, and the lower end acts on the first spring seat 24.

[0061] Referring to Figures 1-3The second elastic assembly comprises a second spring seat 33 and a second spring 32 arranged on the second spring seat 33, wherein the second top rod 31 is provided with a first accommodating cavity at a position corresponding to the first spring seat 24; the second spring seat 33 is arranged at the bottom of the second top rod 31; the second spring 32 is sleeved on the outer side of the second spring seat 33, the upper end of the second spring 32 acts on the second top rod 31, and the lower end acts on the second spring seat 33; the bottom of the second top rod 31 and the outer side of the second spring seat 33 are both provided with a groove for mounting the second spring 32.

[0062] Referring to Figures 1-3 The lower side of the first spring seat 24 is provided with a second accommodating cavity, the nut 25 is arranged in the second accommodating cavity, and a gap 10 exists between the second accommodating cavity and the bottom of the first accommodating cavity of the second top rod 31.

[0063] Referring to Figures 1-3 The bottom of the second top rod 31 is provided with a buffer spring 34, the buffer spring 34 is a rubber spring; the second spring seat 33 is provided with an accommodating groove for accommodating the buffer spring 34; and the buffer spring 34 is arranged in the accommodating groove. By arranging the buffer spring 34 at the bottom of the second top rod 31, direct rigid impact between the bottom of the second top rod 31 and the bottom of the shell 5 can be prevented, so that larger noise is avoided.

[0064] Referring to Figures 1-3 The upper end of the shell 5 is provided with an end cover 9, the end cover 9 is arranged on the shell 5, and a first sealing assembly is arranged between the shell 5 and the end cover 9; the end cover 9 is provided with a through hole, the upper end of the first top rod 21 passes through the through hole and is connected with the brake pedal; a second sealing assembly is arranged between the upper end of the first top rod 21 and the through hole, and the second sealing assembly is arranged on the first top rod 21; in this way, the sealing property of the brake pedal signal simulator of the application can be ensured; in addition, in order to prevent abnormal return of the first top rod 21 and cause the brake to be dragged, a one-way valve 1 is arranged on the end cover 9, the one-way valve 1 is composed of a pressing ring 11, a valve 12 and a pressing plate 13, when the first top rod 21 rises, the air in the shell 5 located at the upper end of the first top rod 21 can flow out in one direction through the one-way valve 1, so that the one-way valve 1 can be reset smoothly.

[0065] Referring to Figures 1-3The middle part of the first jacking rod 21 is provided with a limiting part, the outer diameter of the limiting part is larger than the inner diameter of the through hole on the end cover 9, the limiting part is provided with a mounting groove, and the detection end of the stroke detector 6 is mounted in the mounting groove; by arranging the limiting part, the return stroke of the first jacking rod 21 can be limited, so that the zero point marking of the stroke detector 6 and the pressure sensor 4 is realized.

[0066] Referring to Figures 1-3 The stroke detector 6 comprises a potentiometer 62, a circuit board 63 and an electric socket 61, wherein the potentiometer 62 is mounted in the shell 5, the swing rod of the potentiometer 62 is mounted in the mounting groove of the limiting part of the first jacking rod 21, the electric socket 61 is mounted outside the shell 5, the electric socket 61 and the shell 5 are connected through a third sealing assembly, and a cavity is formed between the electric socket 61 and the shell 5; the circuit board 63 is arranged in the cavity, and the electric socket 61 and the potentiometer 62 are connected with the circuit board 63 through wires.

[0067] Referring to Figures 1-3 The first sealing assembly, the second sealing assembly and the third sealing assembly are all sealing rings 8, and by arranging the first sealing assembly, the second sealing assembly and the third sealing assembly, the sealing of the brake pedal signal simulator of the application can be realized, so that the waterproof effect is ensured.

[0068] Referring to Figures 1-3 The first sliding connection structure and the second sliding connection structure both adopt guide rings 7, the guide rings 7 are respectively mounted on the first jacking rod 21 and the second jacking rod 31, and the outer wall of the guide ring 7 is matched with the inner cavity of the shell 5, so that the sliding of the first jacking rod 21 and the second jacking rod 3 is guided.

[0069] In the embodiment, by adjusting the nut 25 at the bottom of the first jacking rod 21, the initial opening force can be increased or decreased, so that the application range of the brake pedal signal simulator of the application can be expanded.

[0070] Referring to Figures 1-3 The working principle of the brake pedal signal simulator of the application is as follows:

[0071] When the driver steps on the brake pedal, the brake pedal downward pressure is transmitted to the first jacking rod 21 through the pedal push rod, so as to push the first-stage compression module 2 and the second-stage compression module 3 to move, in the process, the second spring 32 is deformed, the bottom of the second jacking rod 31 is in contact with the buffer spring 34, the second jacking rod 31 and the buffer spring 34 form an integral whole, and the process is to give the brake pedal an idle stroke, so as to prevent the brake pedal from being mistakenly stepped on.

[0072] When the driver continues to step on the brake pedal, the first spring 22 is deformed, and the driver feels a linear foot feeling during the deformation of the first spring 22, and the deformation amount of the buffer spring 34 is small because the rigidity coefficient of the first spring 22 is smaller than that of the buffer spring 34;

[0073] When the driver continues to step on the brake pedal, the first spring 22 is deformed, and the driver feels a linear foot feeling during the deformation of the first spring 22, and the deformation amount of the buffer spring 34 is small because the rigidity coefficient of the first spring 22 is smaller than that of the buffer spring 34;

[0074] In the above process, as the stroke of the first top rod 21 changes, the swing arm of the potentiometer 62 moves, so that the potentiometer 62 outputs first and second potential signals, and the pressure sensor 4 also outputs a pressure signal, and by checking the first and second potential signals and the pressure signal, a brake signal closest to the real brake intention of the driver is obtained, and after the brake signal is received by the brake execution module, the EMB executor performs a brake action with a corresponding brake force intensity.

[0075] Embodiment 2

[0076] Referring to Figures 4-6 The redundant control system of the application comprises the brake signal simulator, the signal checking module and the fault alarm module, wherein,

[0077] The brake signal simulator is used to output stroke signals and pressure signals according to the pedal stroke of the driver stepping on the brake pedal, and transmit the stroke signals and the pressure signals to the signal checking module;

[0078] The signal checking module comprises a stroke signal comparative analysis module, a signal selection module and a stroke calculation module, wherein the stroke signal comparative analysis module compares and analyzes the measured value and the theoretically calculated value of the stroke signal, and sends the comparative analysis result to the signal selection module, and sends a fault signal to the fault alarm module;

[0079] The signal selection module selects the corresponding stroke signal or pressure signal according to the signal comparison result and sends it to the stroke calculation module;

[0080] The stroke calculation module is configured to calculate the brake stroke according to the stroke signal or the pressure signal, compare the brake stroke with the idle stroke of the brake signal simulator, and send the brake stroke to the EMB system controller if the brake stroke is greater than the idle stroke; the EMB system controller sends a control instruction to the EMB actuator to perform brake response; and the brake stroke is not sent to the EMB system controller if the brake stroke is less than or equal to the idle stroke.

[0081] Referring to Figures 4-6 The stroke detection sensor generally includes a dual-channel signal potentiometer or a Hall position sensor or a combination of the two. Therefore, the stroke signal output by the stroke detection sensor includes a first potential signal and a second potential signal; the sum of the first potential signal and the second potential signal is equal to a fixed value; and the signal comparison and analysis module compares and analyzes the measured values and the theoretical calculation values of the first potential signal, the second potential signal and the pressure signal according to the following steps:

[0082] Step S1: obtaining the theoretical calculation values of the first potential signal, the second potential signal and the sum of the first potential signal and the second potential signal;

[0083] Step S2: judging whether a first difference between the sum of the first potential signal and the second potential signal and the theoretical calculation value of the sum is within a first error range; if the first difference is within the first error range, it indicates that the stroke detector is in a normal working state, and the brake stroke is calculated by using the optimal solution between the first potential signal and the second potential signal output by the stroke detector, which is used as the brake signal; if the first difference is not within the first error range, it indicates that the stroke detector is in an abnormal working state, and the brake stroke is calculated according to the pressure signal, which is used as the brake signal, and a fault signal is sent to the fault alarm module.

[0084] The step of obtaining the optimal solution between the first potential signal and the second potential signal includes: checking and comparing the measured values and the theoretical calculation values of the first potential signal and the second potential signal, respectively judging whether a second difference between the measured value and the theoretical calculation value of the first potential signal and a third difference between the measured value and the theoretical calculation value of the second potential signal are within a second error range; if the second difference and the third difference are within the second error range, the first potential signal is used to calculate the brake stroke, which is used as the brake signal; if the second difference is not within the second error range and the third difference is within the second error range, the second potential signal is used to calculate the brake stroke, which is used as the brake signal; and if the second difference and the third difference are not within the second error range, the brake stroke is calculated according to the pressure signal, which is used as the brake signal, and a fault signal is sent to the fault alarm module.

[0085] The structure of the potentiometer is shown in Figure 4 The calculation step of the theoretical calculation value of the first potential signal and the second potential signal is

[0086] The theoretical value of the first potential signal SIG1 is:

[0087]

[0088] The theoretical value of the second potential signal SIG2 is:

[0089]

[0090] Since the first potential signal SIG1 and the second potential signal SIG2 are complementary; that is, when the brake signal simulator of the present application is designed to output a full stroke voltage SIG1 = 4.5V, SIG2 = 0.5V at this time, they are complementary and can both be used as stroke simulation signals, and they are redundant signals for each other.

[0091] Taking the brake stroke of the brake pedal (i.e. the movement stroke of the first jacking rod) as the variable x, a functional relationship model between the brake stroke and the first potential signal and the second potential signal is constructed, that is:

[0092] y1 = 0.5; 0 ≤ x ≤ 0.5mm

[0093] y1 = 0.47x + 0.27; x = 0.5 ~ 9mm

[0094] y1 = 4.5; x ≥ 9mm

[0095] y2 = 4.5; 0 ≤ x ≤ 0.5mm

[0096] y2 = 4.375 - 0.47x = 0.5 ~ 9mm;

[0097] y2 = 0.5; x ≥ 9mm

[0098] In the formula, y1 is the first potential signal, unit: V; y2 is the second stroke signal, unit: V; x is the stroke of the jacking rod, unit: mm.

[0099] Through the above functional relationship model, the theoretical calculation value (i.e. the theoretical value) of the first potential signal and the second potential signal can be calculated.

[0100] The specific calculation steps of the theoretical value of the pressure signal are:

[0101] By detecting the brake stroke of the brake pedal, the actual movement stroke of the first jacking rod is obtained, and according to the structural parameters in the first elastic component and the second elastic component, the theoretical value of the pressure signal is calculated, wherein,

[0102] The function relationship between the pedal pressure (i.e. the axial force F borne by the first jacking rod) and the output pressure signal is:

[0103] F 力 = 3.704F + 193;

[0104] In the formula, F 力 is the pressure value of the pressure sensor, unit: LSB; F is the axial force borne by the first jacking rod, unit: N;

[0105] The axial force borne by the first jacking rod F is:

[0106] F = k1S1 + k2S2 + k3S3;

[0107] In the formula, k1 is the first elastic coefficient of the first spring; S1 is the working height of the first spring; k2 is the elastic coefficient of the second spring; S2 is the working height of the second spring; k3 is the elastic coefficient of the rubber spring; S3 is the working height of the rubber spring.

[0108] The total stroke of the pedal is calculated by the following formula:

[0109]

[0110] In the formula, S 总 represents the total stroke of the pedal, F represents the pressure value read by the pressure sensor, k1, k2 and k3 respectively represent the elastic coefficients of the first spring, the second spring and the rubber spring, and X represents the mechanical idle stroke of the brake signal simulator (which is known at the design time).

[0111] By taking the total stroke of the pedal as the standard for the maximum value of the driver's requested braking force, if the driver steps to the maximum stroke equal to the total stroke of the pedal, the EMB actuator provides the maximum braking force for braking.

[0112] Embodiment 3

[0113] Referring to Figure 7 , the redundant control system in the embodiment comprises the brake signal simulator, the signal detection module, the first stroke calculation module, the stroke verification module, the second stroke calculation module, the signal comparison module, the signal sending module and the fault alarm module, wherein,

[0114] The signal detection module comprises a potentiometer or / and a Hall sensor for detecting the stroke of the first jacking rod and a pressure sensor for detecting the total pressure of the brake pedal, wherein the potentiometer or / and the Hall sensor outputs a stroke signal to the first stroke calculation module; the stroke signal comprises a first potential signal and a second potential signal; the pressure sensor outputs a pressure signal to the first stroke calculation module;

[0115] The first stroke calculation module calculates the pedal stroke according to the first potential signal x1, the second potential signal x2 and the pressure signal f output by the stroke detector and the pressure sensor respectively, and outputs the first pedal stroke signal l1, the second pedal stroke signal l2 and the third pedal stroke signal l3, and sends them to the stroke verification module;

[0116] The stroke verification module analyzes whether the first pedal stroke signal, the second pedal stroke signal and the third pedal stroke signal are abnormal, and sends the abnormal pedal stroke signal to the fault alarm module, and the fault alarm module alarms; the stroke verification module sends all the normal pedal stroke signals to the second stroke calculation module;

[0117] In this embodiment, the first pedal stroke signal l1, the second pedal stroke signal l2 and the third pedal stroke signal l3 are calculated according to the first potential signal x1, the second potential signal x2 and the pressure signal f respectively, and since the first potential signal x1 and the second potential signal x2 are complementary, the first pedal stroke signal l1 calculated by the first potential signal x1 is consistent with the second pedal stroke signal l2 calculated by the second potential signal x2, and the third pedal stroke signal l3 is calculated by the pressure signal f;

[0118] The first pedal stroke signal l1, the second pedal stroke signal l2 and the third pedal stroke signal l3 are compared;

[0119] If l1=l2≠l3, it means that the third pedal stroke signal l3 is invalid, and the fault signal (i.e. the third pedal stroke signal l3) is sent to the fault alarm module;

[0120] If l1≠l2=l3, it means that the first pedal stroke signal l1 is invalid, and the fault signal (i.e. the first pedal stroke signal l1) is sent to the fault alarm module;

[0121] If l2≠l1=l3, it means that the second pedal stroke signal l2 is invalid, and the fault signal (i.e. the second pedal stroke signal l2) is sent to the fault alarm module;

[0122] If l1=l2=l3, it means that the first pedal stroke signal l1, the second pedal stroke signal l2 and the third pedal stroke signal l3 are all normal;

[0123] If l1≠l2≠l3, the signal with the largest deviation is sent to the fault alarm module, and the other two signals are sent to the second calculation module.

[0124] The above process is that the three signals check each other.

[0125] The second stroke calculation module calculates the average stroke of the received normal pedal stroke signal and sends the average stroke to the signal comparison module;

[0126] The signal comparison module is used to determine whether the calculated average stroke is greater than the idle stroke of the brake signal simulator.

[0127] If the average stroke is greater than the idle stroke of the brake signal simulator, the signal sending module sends the average stroke to the EMB controller; the EMB system controller sends a control instruction to the EMB actuator according to the average stroke to perform a brake response.

[0128] If the average stroke is not greater than the idle stroke of the brake signal simulator, the signal sending module does not send the average stroke to the EMB controller.

[0129] The above is the preferred embodiment of the present application, but the embodiments of the present application are not limited by the above, and any changes, modifications, substitutions, combinations, simplifications made without departing from the spirit and principles of the present application should be equivalent replacement methods, and are included in the protection scope of the present application.

Claims

1. A braking signal simulator, characterized in that, It includes a housing, a primary compression module, a secondary compression module disposed within the housing, and a signal detection module for detecting the magnitude of the braking force; wherein, The primary compression module is located above the secondary compression module; The primary compression module includes a first push rod and a first elastic component disposed at the lower end of the first push rod. The upper end of the first push rod is connected to the brake pedal. The first push rod is installed in the housing via a first sliding connection structure. The first sliding connection structure is used to cause the first push rod to move along its axial direction. The secondary compression module includes a second push rod and a second elastic component disposed at the lower end of the second push rod, wherein the axial direction of the second push rod coincides with the axial direction of the first push rod, and the second push rod is installed in the housing through a second sliding connection structure; the second sliding connection structure is used to cause the second push rod to move along its axial direction; The signal detection module includes a stroke detector and a pressure sensor. The stroke detector is installed inside the housing and is used to detect the movement stroke of the first push rod and output a stroke signal. The pressure sensor is located at the bottom of the housing and is used to detect the resultant force of the pressure of the first push rod and the second push rod and output a pressure signal. The first elastic component includes a first spring seat and a first spring disposed on the first spring seat. The first spring seat is disposed at the bottom of the first push rod. The bottom of the first push rod passes through the first spring seat and is connected to a nut. A guide hole is provided on the first spring seat at a position corresponding to the first push rod. A bushing that mates with the first push rod is provided on the inner wall of the guide hole. The outer diameter of the nut is larger than the inner diameter of the guide hole. The first spring is sleeved on the first push rod, with its upper end acting on the first push rod and its lower end acting on the first spring seat. The second elastic component includes a second spring seat and a second spring disposed on the second spring seat. The second push rod has a first receiving cavity at a position corresponding to the first spring seat. The second spring seat is disposed at the bottom of the second push rod. The second spring is sleeved on the outside of the second spring seat, with the upper end of the second spring acting on the second push rod and the lower end acting on the second spring seat.

2. The braking signal simulator according to claim 1, characterized in that, The bottom of the second push rod is provided with a buffer spring, which is a rubber spring; the second spring seat is provided with a receiving groove for accommodating the buffer spring.

3. The braking signal simulator according to claim 1, characterized in that, An end cap is provided at the upper end of the housing, and the end cap is installed on the housing. A first sealing assembly is provided between the housing and the end cap. A through hole is provided on the end cap, and the upper end of the first push rod passes through the through hole and is connected to the brake pedal. A second sealing assembly is provided between the upper end of the first push rod and the through hole, and the second sealing assembly is installed on the first push rod.

4. The braking signal simulator according to claim 3, characterized in that, The first push rod has a limiting part in the middle, the outer diameter of the limiting part is larger than the inner diameter of the through hole on the end cover, and the limiting part has a mounting groove, and the detection end of the stroke detector is installed in the mounting groove.

5. The braking signal simulator according to claim 1, characterized in that, The travel detector includes a potentiometer and / or a Hall sensor.

6. A redundant control system employing the braking signal simulator according to any one of claims 1-5, characterized in that, This includes the aforementioned brake signal simulator, signal verification module, and fault alarm module, wherein, The brake signal simulator is used to output travel signal and pressure signal according to the pedal travel of the driver pressing the brake pedal, and transmit the travel signal and pressure signal to the signal verification module; The signal verification module includes a travel signal comparison and analysis module, a signal selection module, and a travel calculation module, wherein... The travel signal comparison and analysis module compares and analyzes the measured value and theoretical calculated value of the travel signal, and sends the comparison and analysis results to the signal selection module, while sending the fault signal to the fault alarm module. The signal selection module selects the corresponding stroke signal or pressure signal based on the signal comparison result and sends it to the stroke calculation module. The stroke calculation module is used to calculate the braking stroke based on the stroke signal or pressure signal, and compare the braking stroke with the empty stroke of the braking signal simulator. If the braking stroke is greater than the empty stroke, the braking stroke is sent to the EMB system controller. The EMB system controller sends control commands to the EMB actuator to perform braking response. If the braking stroke is less than or equal to the empty stroke, the braking stroke is not sent to the EMB system controller.

7. The redundant control system according to claim 6, characterized in that, The obtained stroke signal includes a first potential signal and a second potential signal; the sum of the first potential signal and the second potential signal is equal to a fixed value; the signal comparison and analysis module compares and analyzes the measured values ​​and theoretical calculated values ​​of the first potential signal, the second potential signal, and the pressure signal according to the following steps: Step S1: Obtain the theoretical calculated value of the first potential signal, the theoretical calculated value of the second potential signal, and the theoretical calculated value of the sum of the first potential signal and the second potential signal; Step S2: Determine whether the first difference between the sum of the first potential signal and the second potential signal and the theoretically calculated value of the sum is within the first error range; If the first difference is within the first error range, it indicates that the stroke detector is in normal working condition. The braking stroke is calculated using the optimal solution between the first potential signal and the second potential signal output by the stroke detector, and this solution is used as the braking signal. If the first difference is not within the first error range, it indicates that the stroke detector is in an abnormal working state. At this time, the braking stroke is calculated based on the pressure signal and used as the braking signal. At the same time, the fault signal is sent to the fault alarm module.

8. The redundant control system according to claim 7, characterized in that, In step S2, the step of obtaining the optimal solution between the first potential signal and the second potential signal is as follows: The measured and theoretically calculated values ​​of the first and second potential signals are compared and verified. The second difference between the measured and theoretically calculated values ​​of the first and second potential signals and the third difference between the measured and theoretically calculated values ​​of the second potential signal are determined to be within the second error range. If both the second and third differences are within the second error range, then the first potential signal is used to calculate the braking stroke and is used as the braking signal. If the second difference is not within the second error range, but the third difference is within the second error range, then the second potential signal is used to calculate the braking stroke and is used as the braking signal. If both the second and third differences are outside the second error range, the braking stroke is calculated based on the pressure signal and used as the braking signal. At the same time, a fault signal is sent to the fault alarm module.

9. A redundant control system employing the braking signal simulator according to any one of claims 1-5, characterized in that, This includes the aforementioned brake signal simulator, first stroke calculation module, stroke verification module, second stroke calculation module, signal comparison module, signal transmission module, and fault alarm module, wherein... The signal detection module in the brake signal simulator includes a potentiometer and / or a Hall effect sensor for detecting the travel of the first push rod and a pressure sensor for detecting the total pressure of the brake pedal. The potentiometer and / or the Hall effect sensor outputs a travel signal to the first travel calculation module. The travel signal includes a first potential signal and a second potential signal. The pressure sensor outputs a pressure signal to the first travel calculation module. The first travel calculation module calculates the pedal travel of the driver based on the first potential signal and the second potential signal output by the travel detector and the pressure signal output by the pressure sensor, respectively. The first travel calculation module outputs the first pedal travel signal, the second pedal travel signal and the third pedal travel signal, respectively, and sends the first pedal travel signal, the second pedal travel signal and the third pedal travel signal to the travel verification module. The travel verification module analyzes the first pedal travel signal, the second pedal travel signal, and the third pedal travel signal for any abnormalities, and sends the pedal travel signals with abnormalities to the fault alarm module, which then issues an alarm. The travel verification module sends all normal pedal travel signals to the second travel calculation module. The second stroke calculation module calculates the average stroke of the received normal pedal stroke signal and sends the average stroke to the signal comparison module; The signal comparison module is used to determine whether the calculated average stroke value is greater than the empty stroke of the brake signal simulator; If the average travel value is greater than the idle travel value of the brake signal simulator, the signal sending module sends the average travel value to the EMB controller; the EMB system controller generates a braking command based on the average travel value and sends it to the EMB actuator to perform a braking response. If the average travel value is less than or equal to the empty travel value of the brake signal simulator, the signal sending module will not send the average travel value to the EMB controller.

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