A personalized pedal feel simulator based on driver braking style

Abstract

This invention discloses a personalized pedal feel simulator based on the driver's braking style, belonging to the field of pedal feel simulator technology. It solves the technical problem that pedal feel simulators cannot meet the personalized pedal feel requirements of drivers. The key technical points are that the pedal feel simulator includes a pedal cylinder, a simulated cylinder, a pedal displacement sensor, a first solenoid valve, a second solenoid valve, a third solenoid valve, and an electronic control unit (ECU). This pedal feel simulator has a simple structure, high integration, and is easy to install and maintain. It employs three pedal displacement and feedback force curves with different stiffnesses to provide a more realistic foot feel. Through different combinations of springs and the control of the solenoid valves, it achieves three pedal feel feedback modes under "aggressive," "normal," and "conservative" braking styles, meeting the driver's personalized pedal feel requirements, matching the driver's differentiated braking style, enhancing the driving experience, and enriching driving pleasure.

Description

Technical Field

[0001] This application relates to the field of pedal feel simulator technology, and more particularly to a personalized pedal feel simulator based on the driver's braking style. Background Technology

[0002] The development of intelligent connected electric vehicles has presented new challenges to braking systems. Traditional vacuum-assisted braking systems, unable to achieve functions such as active braking and regenerative braking, are gradually being replaced by brake-by-wire systems with decoupling characteristics. Brake-by-wire systems control the movement of the brake motor based on braking intention signals collected by pedal displacement sensors. The motor's rotation is converted into piston translational motion through reduction gears, torque amplification devices, and motion conversion mechanisms, thereby establishing brake fluid pressure in the active cylinder. Brake-by-wire systems offer advantages such as compact structure, rapid response, precise control, and strong compatibility, making them ideal actuators for achieving autonomous driving and a recognized mainstream solution for next-generation automotive braking systems.

[0003] In brake-by-wire systems, the brake pedal and hydraulic circuit are completely decoupled, preventing the system from providing pedal feedback to the driver via the hydraulic circuit. Therefore, a pedal feel simulator is needed to achieve a feel similar to that of a traditional braking system. Furthermore, due to differences in age, body type, personality, driving experience, and driving style, drivers exhibit significant variations in braking behavior, resulting in different braking styles. However, current pedal feel simulators can only simulate a limited range of pedal sensations, failing to meet the personalized pedal feel requirements of drivers and effectively matching their diverse braking habits. This has become a pressing issue in the field of brake-by-wire systems. Summary of the Invention

[0004] This application provides a personalized pedal feel simulator based on the driver's braking style. Its technical purpose is to meet the driver's personalized pedal feel needs, so that the pedal feel simulator can effectively match the driver's different braking habits and obtain a more realistic pedal feel.

[0005] The above-mentioned technical objective of this application is achieved through the following technical solution:

[0006] A personalized pedal feel simulator based on driver braking style includes a brake pedal, a pedal cylinder, a reservoir, a pedal displacement sensor, an ECU, and a simulated cylinder. The brake pedal is connected to the pedal cylinder, the pedal displacement sensor is connected to the brake pedal, the pedal cylinder is connected to the reservoir, the pedal cylinder and the simulated cylinder are connected through a solenoid valve assembly and pipelines, and both the solenoid valve assembly and the pedal displacement sensor are connected to the ECU.

[0007] The simulation cylinder has a first inlet, a second inlet, and a third inlet at its top. The simulation cylinder has a first chamber and a second chamber that are interconnected. The first chamber contains a first piston and a second piston, while the second chamber contains a third piston, a fourth piston, and a fifth piston. The first piston is connected to a first spring, the second piston to a second spring, and the third piston to a third spring. The fourth piston is connected to a first sleeve near the third piston, and the first sleeve contains a fourth spring, which is connected to the second piston. The fifth piston is connected to a push rod, one end of which is inside the first sleeve and connected to the fourth spring.

[0008] The third piston is connected to the second sleeve in the direction close to the second piston. The third spring is sleeved outside the second sleeve. One end of the first sleeve is located inside the second sleeve and the end is connected to the second piston.

[0009] The first piston, the third piston, and the fourth piston are respectively provided with a first through hole, a second through hole, and a third through hole; the second spring passes through the first through hole; the second sleeve is provided in the second through hole, and the first sleeve is provided in the third through hole;

[0010] The space formed by the fourth piston, the third piston, and the inner wall of the simulated cylinder is the first hydraulic chamber; the space formed by the fifth piston, the fourth piston, and the inner wall of the simulated cylinder is the second hydraulic chamber; the space formed by the fifth piston and the inner wall of the simulated cylinder is the third hydraulic chamber; the first inlet is connected to the first hydraulic chamber, the second inlet is connected to the second hydraulic chamber, and the third inlet is connected to the third hydraulic chamber.

[0011] The simulated cylinder has a limiting block on its inner wall to limit the position of the fifth piston.

[0012] The beneficial effects of this application are as follows: The personalized pedal feel simulator based on the driver's braking style described in this application has a simple structure and high integration. The components are detachably connected, which facilitates installation and maintenance. It uses three springs with different stiffnesses to simulate pedal feel, which can provide a more realistic pedal feel compared to a two-stage pedal feel simulator. It can achieve differentiated braking foot feel feedback by controlling the on / off state of the solenoid valve and different combinations of springs, so as to meet the driver's personalized pedal feel needs. In addition, it can further enrich the driving experience and enhance driving pleasure. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the personalized pedal feel simulator based on driver braking style described in this application;

[0014] Figure 2 This is a schematic diagram of the simulated cylinder structure;

[0015] Figure 3 For simulating cylinder shaft projection;

[0016] Figure 4 A schematic diagram illustrating the pedal feel feedback force provided by the simulated cylinder in different modes in this application;

[0017] In the diagram: 1-Brake pedal; 2-Pedal displacement sensor; 3-Pedal push rod; 4-Buffer pad; 5-Pedal piston; 6-Pedal spring; 7-Pedal cylinder; 8-Pedal hydraulic chamber; 9-Reservoir; 10-First solenoid valve; 11-Second solenoid valve; 12-Third solenoid valve; 13-First pipeline; 14-Second pipeline; 15-Third pipeline; 16-ECU; 17-Simulated cylinder; 18-First piston; 19-Second piston; 20-Third piston; 21-Fourth piston; 22-Fifth piston; 23-First spring; 2 4-Second spring; 25-Third spring; 26-Fourth spring; 27-First hydraulic chamber; 28-Second hydraulic chamber; 29-Third hydraulic chamber; 30-First inlet; 31-Second inlet; 32-Third inlet; 33-First chamber; 34-Second chamber; 35-Limiting block; 36-Sealing ring; 37-Push rod; 38-First sleeve; 39-Second sleeve; 40-First concave surface; 41-Second concave surface; 42-Third concave surface; 43-First through hole; 44-Second through hole; 45-Third through hole; 46-Shoulder. Detailed Implementation

[0018] The technical solution of this application will be described in detail below with reference to the accompanying drawings.

[0019] like Figure 1 As shown, the personalized pedal feel simulator based on driver braking style described in this application includes a brake pedal, a pedal cylinder, a reservoir, a pedal displacement sensor, an ECU, and a simulated cylinder. The brake pedal is connected to the pedal cylinder, the pedal displacement sensor is connected to the brake pedal, the pedal cylinder is connected to the reservoir, the pedal cylinder and the simulated cylinder are connected through a solenoid valve assembly and pipelines, and both the solenoid valve assembly and the pedal displacement sensor are connected to the ECU.

[0020] The pedal cylinder has a pedal hydraulic chamber inside, which contains a pedal piston and a pedal spring that are connected to each other. The pedal piston is connected to the brake pedal via a pedal push rod, and the pedal displacement sensor is connected to the brake pedal and the pedal piston via the pedal push rod.

[0021] As a specific embodiment, a buffer pad is provided on the side where the pedal piston is connected to the pedal push rod.

[0022] like Figure 2 and Figure 3As shown, the simulation cylinder has a first inlet, a second inlet, and a third inlet at the top. The simulation cylinder has a first chamber and a second chamber that are interconnected. The first chamber contains a first piston and a second piston, and the second chamber contains a third piston, a fourth piston, and a fifth piston. The first piston is connected to a first spring, the second piston is connected to a second spring, the third piston is connected to a third spring, and the fourth piston is connected to a first sleeve near the third piston. The first sleeve contains a fourth spring, which is connected to the second piston. The fifth piston is connected to a push rod, one end of which is inside the first sleeve and connected to the fourth spring.

[0023] The third piston is connected to the second sleeve in the direction close to the second piston. The third spring is sleeved outside the second sleeve. One end of the first sleeve is located inside the second sleeve and the end is connected to the second piston.

[0024] The first piston, the third piston, and the fourth piston are respectively provided with a first through hole, a second through hole, and a third through hole; the second spring passes through the first through hole; the second sleeve is located in the second through hole, and the first sleeve is located in the third through hole.

[0025] The space formed by the fourth piston, the third piston, and the inner wall of the simulated cylinder is the first hydraulic chamber; the space formed by the fifth piston, the fourth piston, and the inner wall of the simulated cylinder is the second hydraulic chamber; the space formed by the fifth piston and the inner wall of the simulated cylinder is the third hydraulic chamber; the first inlet is connected to the first hydraulic chamber, the second inlet is connected to the second hydraulic chamber, and the third inlet is connected to the third hydraulic chamber.

[0026] The simulated cylinder has a limiting block on its inner wall to limit the position of the fifth piston.

[0027] Specifically, the solenoid valve assembly includes a first solenoid valve, a second solenoid valve, and a third solenoid valve, and the pipeline includes a first pipeline, a second pipeline, and a third pipeline. The first pipeline connects the pedal cylinder and the first liquid inlet through the first solenoid valve, the second pipeline connects the pedal cylinder and the second liquid inlet through the second solenoid valve, and the third pipeline connects the pedal cylinder and the third liquid inlet through the third solenoid valve.

[0028] In a specific embodiment, the surfaces of the first piston near the second piston, the third piston near the fourth piston, and the fourth piston near the fifth piston are respectively provided with a first concave surface, a third concave surface, and a fourth concave surface. The size of the first concave surface is greater than or equal to the size of the second piston, the size of the third concave surface is greater than or equal to the size of the fourth piston, and the size of the fourth concave surface is greater than or equal to the size of the fifth piston.

[0029] In a specific embodiment, buffer pads are provided in the first concave surface, the third concave surface, and the fourth concave surface, and a buffer pad is provided on the side of the limiting block near the fifth piston.

[0030] In a specific embodiment, the inner wall of the second sleeve of the third piston is provided with a sealing ring, and the first sleeve of the fourth piston is sealed to the second sleeve through the sealing ring.

[0031] In a specific embodiment, the inner wall of the first sleeve of the fourth piston is provided with a sealing ring, and the push rod of the fifth piston is sealed to the first sleeve through the sealing ring.

[0032] In a specific embodiment, a shoulder is provided at the junction of the first cavity and the second cavity, and the third spring is connected to both ends of the shoulder.

[0033] The pedal feel simulator described in this application includes three feel modes, and the pedal feel feedback force provided by the simulated cylinder in the three feel modes is as follows: Figure 4 As shown, its specific working principle is as follows:

[0034] Mode 1:

[0035] In the first stage, there is a distance between the first piston 18 and the second piston 19. The ECU 16 controls the first solenoid valve 10 to close, and simultaneously controls the second solenoid valve 11 to open and the third solenoid valve 12 to close. Brake fluid flows from the pedal hydraulic chamber 8 of the pedal cylinder 7 through the second pipe 14 into the second inlet 31, and enters the second hydraulic chamber 28, pushing the fourth piston 21 to move to the right. In the first stage, the second spring 24 is compressed, so the second piston 19 moves towards the first piston 18. The slope of the feedback force is the stiffness k2 of the second spring 24.

[0036] As the fourth piston 21 continues to move to the right, the second stage begins after the second piston 19 contacts the first piston 18, simultaneously compressing the first spring 23 and the second spring 24. The slope of the feedback force is the sum of the stiffness of the first spring 23 and the second spring 24, and k1 + k2.

[0037] After the fourth piston 21 continues to move to the right to overcome the empty stroke, the fourth piston 21 contacts the third piston 20 and begins the third stage, while compressing the first spring 23, the second spring 24 and the third spring 25. The slope of the feedback force is the sum of the stiffness of the first spring 23, the second spring 24 and the third spring 25 and k1+k2+k3.

[0038] Mode 2:

[0039] In the first stage, there is a distance between the second sleeve 39 on the third piston 20 and the second piston 19. The ECU 16 controls the first solenoid valve 10 to open, and simultaneously controls the second solenoid valve 11 to close, while the third solenoid valve 12 is de-energized and closed. Brake fluid flows from the pedal hydraulic chamber 8 of the pedal cylinder 7 through the first pipe 13 into the first inlet 30, and enters the first hydraulic chamber 27, pushing the third piston 20 to move to the right. In the first stage, the third spring 25 is compressed, and the feedback force slope is the stiffness k3 of the third spring 25.

[0040] After the third piston 20 continues to move to the right to overcome the empty stroke, the second sleeve 39 of the third piston 20 contacts the second piston 19, starting the second stage, while compressing the second spring 24 and the third spring 25. The slope of the feedback force is the sum of the stiffness of the second spring 24 and the third spring 25 and k2+k3.

[0041] The third piston 20 continues to move to the right until the second piston 19 contacts the first piston 18, at which point the third stage begins, simultaneously compressing the first spring 23, the second spring 24, and the third spring 25. The slope of the feedback force is the sum of the stiffness of the first spring 23, the second spring 24, and the third spring 25, and k1 + k2 + k3.

[0042] Mode 3:

[0043] In the first stage, there is a distance between the fifth piston 22 and the fourth piston 21. The ECU 16 controls the first solenoid valve 10 to be de-energized and closed, while simultaneously controlling the second solenoid valve 11 to be energized and closed, and the third solenoid valve 12 to be energized and opened. Brake fluid flows from the pedal hydraulic chamber 8 of the pedal cylinder 7 through the third pipe 15 into the third inlet port 32, and enters the third hydraulic chamber 29, pushing the fifth piston 22 to move to the right. In the first stage, the second spring 24 and the fourth spring 26 are compressed, and the feedback force slope is the series stiffness of the second spring 24 and the fourth spring 26, k2k4 / k2+k4.

[0044] As the fifth piston 22 continues to move to the right, causing the second piston 19 to contact the first piston 18, the second stage begins. The fifth piston 22 simultaneously compresses the first spring 23, the second spring 24, and the fourth spring 26. The slope of the feedback force is the sum of the series stiffnesses of the first spring 23, the second spring 24, and the fourth spring 26, k1+k2k4 / k2+k4.

[0045] There is a distance between the fourth piston 21 and the third piston 20. The fifth piston 22 continues to move to the right until the fifth piston 22, the fourth piston 21 and the third piston 20 come into contact at the same time. Then the third stage begins, compressing the first spring 23, the second spring 24, the third spring 25 and the fourth spring 26 at the same time. The slope of the feedback force is the sum of the series stiffnesses of the first spring 23, the third spring 25 and the second spring 24 and the fourth spring 26, k1+k3+(k2k4 / k2+k4).

[0046] The pedal spring only serves to reset the pedal piston. Its stiffness is relatively low, and the slope of the feedback force it generates is fixed. Combined with the three modes of the simulated cylinder, it produces three different pedal feel simulator operating modes. When the stiffness of the first spring 23, the second spring 24, the third spring 25, and the fourth spring 26 satisfies k1 = k2 > k3 > k4, then mode 1, mode 2, and mode 3 correspond to hard, moderate, and light pedal feel, respectively. In this mode, mode 1 matches a "aggressive" braking behavior driver, mode 2 matches a "moderate" braking behavior driver, and mode 3 matches a "conservative" braking behavior driver, satisfying the driver's personalized pedal feel needs.

[0047] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A driver brake style based personalized pedal feel simulator, characterized by, The brake pedal (1), the pedal cylinder (7), the liquid storage tank (9), the pedal displacement sensor (2), the ECU (16) and the simulation cylinder (17) are connected, the pedal displacement sensor (2) is connected with the brake pedal (1), the pedal cylinder (7) is connected with the liquid storage tank (9), the pedal cylinder (7) and the simulation cylinder (17) are connected through the electromagnetic valve group and the pipeline, and the electromagnetic valve group and the pedal displacement sensor (2) are connected with the ECU (16); The first liquid inlet (30), the second liquid inlet (31) and the third liquid inlet (32) are arranged on the top of the simulation cylinder (17), the first cavity (33) and the second cavity (34) are arranged in the simulation cylinder (17) and are communicated with each other, the first piston (18) and the second piston (19) are arranged in the first cavity (33), the third piston (20), the fourth piston (21) and the fifth piston (22) are arranged in the second cavity (34), the first spring (23) is connected with the first piston (18), the second spring (24) is connected with the second piston (19), the third spring (25) is connected with the third piston (20), the first sleeve (38) is arranged in the direction close to the third piston (20) and is connected with the fourth piston (21), the fourth spring (26) is arranged in the first sleeve (38) and is connected with the second piston (19), and the push rod (37) is connected with the fifth piston (22), one end of the push rod (37) is arranged in the first sleeve (38) and is connected with the fourth spring (26); The second sleeve (39) is arranged in the direction close to the second piston (19) and is connected with the third piston (20), the third spring (25) is sleeved outside the second sleeve (39), one end of the first sleeve (38) is arranged in the second sleeve (39) and the end is connected with the second piston (19); The first through hole (43), the second through hole (44) and the third through hole (45) are arranged on the first piston (18), the third piston (20) and the fourth piston (21) respectively, the second spring (24) penetrates through the first through hole (43), the second sleeve (39) is arranged in the second through hole (44), and the first sleeve (38) is arranged in the third through hole (45); The space formed by the fourth piston (21), the third piston (20) and the inner wall of the simulation cylinder (17) is the first hydraulic cavity (27), the space formed by the fifth piston (22), the fourth piston (21) and the inner wall of the simulation cylinder (17) is the second hydraulic cavity (28), the space formed by the fifth piston (22) and the inner wall of the simulation cylinder (17) is the third hydraulic cavity (29), the first liquid inlet (30) is communicated with the first hydraulic cavity (27), the second liquid inlet (31) is communicated with the second hydraulic cavity (28), and the third liquid inlet (32) is communicated with the third hydraulic cavity (29); The limiting block (35) is arranged on the inner wall of the simulation cylinder (17), and the limiting block (35) is used for limiting the position of the fifth piston (22). The electromagnetic valve group comprises a first electromagnetic valve (10), a second electromagnetic valve (11) and a third electromagnetic valve (12), and the pipeline comprises a first pipeline (13), a second pipeline (14) and a third pipeline (15), the first pipeline (13) is communicated with the pedal cylinder (7) and the first liquid inlet (30) through the first electromagnetic valve (10), the second pipeline (14) is communicated with the pedal cylinder (7) and the second liquid inlet (31) through the second electromagnetic valve (11), and the third pipeline (15) is communicated with the pedal cylinder (7) and the third liquid inlet (32) through the third electromagnetic valve (12); The working principle of the pedal feeling simulator comprises: Mode 1: In the first stage, there is a distance between the first piston (18) and the second piston (19), the ECU (16) controls the first electromagnetic valve (10) to be powered off and closed, controls the second electromagnetic valve (11) to be powered on and opened, and controls the third electromagnetic valve (12) to be powered off and closed, brake fluid flows into the second liquid inlet (31) from the pedal hydraulic chamber (8) of the pedal cylinder (7) through the second pipeline (14), enters the second hydraulic chamber (28) to push the fourth piston (21) to move rightwards, the first spring (23) and the second spring (24) are compressed in the second stage, and the second piston (19) moves towards the first piston (18); After the fourth piston (21) continues to move rightwards and the second piston (19) contacts the first piston (18), the second stage starts, and the first spring (23) and the second spring (24) are compressed; After the fourth piston (21) continues to move rightwards and overcomes the idle stroke, the fourth piston (21) contacts the third piston (20), the third stage starts, and the first spring (23), the second spring (24) and the third spring (25) are compressed; Mode 2: In the first stage, the second sleeve (39) on the third piston (20) is away from the second piston (19), the ECU (16) controls the first electromagnetic valve (10) to be powered on and opened, controls the second electromagnetic valve (11) to be powered off and closed, and controls the third electromagnetic valve (12) to be powered off and closed, brake fluid flows into the first liquid inlet (30) from the pedal hydraulic chamber (8) of the pedal cylinder (7) through the first pipeline (13), enters the first hydraulic chamber (27) to push the third piston (20) to move rightwards, and the third spring (25) is compressed in the first stage; After the third piston (20) continues to move rightwards and overcomes the idle stroke, the second sleeve (39) on the third piston (20) contacts the second piston (19), the second stage starts, and the second spring (24) and the third spring (25) are compressed; After the third piston (20) continues to move rightwards and the second piston (19) contacts the first piston (18), the third stage starts, and the first spring (23), the second spring (24) and the third spring (25) are compressed; Mode 3: In the first stage, there is a distance between the fifth piston (22) and the fourth piston (21), the ECU (16) controls the first solenoid valve (10) to be powered off and closed, controls the second solenoid valve (11) to be powered on and closed, and controls the third solenoid valve (12) to be powered on and opened. Brake fluid flows from the pedal hydraulic chamber (8) of the pedal cylinder (7) through the third pipeline (15) into the third inlet (32), enters the third hydraulic chamber (29), and pushes the fifth piston (22) to move to the right, compressing the second spring (24) and the fourth spring (26) in the first stage. After the fifth piston (22) continues to move to the right and the second piston (19) contacts the first piston (18), the second stage begins, and the fifth piston (22) simultaneously compresses the first spring (23), the second spring (24), and the fourth spring (26). After the fourth piston (21) and the third piston (20) are in contact, the third stage begins, and the first spring (23), the second spring (24), the third spring (25), and the fourth spring (26) are compressed. The pedal cylinder (7) is internally provided with a pedal hydraulic chamber (8).

2. The individualized pedal feel simulator of claim 1, wherein, The pedal hydraulic chamber (8) is provided with a pedal piston (5) and a pedal spring (6) connected to each other. The pedal piston (5) is connected to the brake pedal (1) through a pedal push rod (3), and the pedal displacement sensor (2) is connected to the brake pedal (1) and the pedal piston (5) through the pedal push rod (3).

3. The individualized pedal feel simulator of claim 2, wherein, The side of the pedal piston (5) connected to the pedal push rod (3) is provided with a buffer pad (4).

4. The individualized pedal feel simulator of claim 1, wherein, The surface of the first piston (18) close to the second piston (19), the surface of the third piston (20) close to the fourth piston (21), and the surface of the fourth piston (21) close to the fifth piston (22) are respectively provided with a first concave surface (40), a second concave surface (41), and a third concave surface (42). The size of the first concave surface (40) is greater than or equal to the size of the second piston (19), the size of the second concave surface (41) is greater than or equal to the size of the fourth piston (21), and the size of the third concave surface (42) is greater than or equal to the size of the fifth piston (22).

5. The individualized pedal feel simulator of claim 4, wherein, The first concave surface (40), the second concave surface (41), and the third concave surface (42) are all provided with a buffer pad (4), and the side of the limiting block (35) close to the fifth piston (22) is also provided with a buffer pad (4).

6. The individualized pedal feel simulator of claim 1, wherein, The inner wall of the second sleeve (39) of the third piston (20) is provided with a sealing ring (36), and the first sleeve (38) of the fourth piston (21) is sealingly connected to the second sleeve (39) through the sealing ring (36).

7. The individualized pedal feel simulator of claim 1, wherein, The inner wall of the first sleeve (38) of the fourth piston (21) is provided with a sealing ring (36), and the push rod (37) of the fifth piston (22) is sealingly connected to the first sleeve (38) through the sealing ring (36).

8. The individualized pedal feel simulator of claim 1, wherein, The intersection of the first cavity (33) and the second cavity (34) is provided with a shoulder (46), and the third spring (25) is connected to both ends of the shoulder (46).

9. The individualized pedal feel simulator of claim 1, wherein, The stiffness of the first spring (23), the second spring (24), the third spring (25), and the fourth spring (26) satisfies k 1 =k 2 >k 3 >k 4 ， wherein, k 1 K1 represents the stiffness of the first spring (23), k 2 K2 represents the stiffness of the second spring (24), k 3 K3 represents the stiffness of the third spring (25), k 4 K4 represents the stiffness of the fourth spring (26).

Images