Pedal feeling test device and test method for passenger car brake pedal

Abstract

The application discloses a kind of passenger car brake pedal's pedal feeling test device and test method, including fixed base, mobile base, adjustable seat support, tension-compression actuator, booster support and load brake unit;Booster support and load brake unit are installed on fixed base;Booster is installed on fixed base by booster support;Mobile base can be laterally slid relative to fixed base, and the switching of objective test position and subjective evaluation position is carried out;Adjustable seat support is installed on mobile base;Tension-compression actuator is fixed on mobile base and located in adjustable seat support side, and tension-compression force sensor and linear displacement sensor are installed on tension-compression actuator.The application can realize the automatic testing of brake pedal feeling, and the test method of driver's subjective evaluation is considered simultaneously, the automatic processing of data can improve test data processing efficiency, and reduce test cost.

Description

Technical Field

[0001] This invention belongs to the field of passenger vehicle testing technology, specifically relating to a pedal feel testing device and method for passenger vehicle brake pedals. Background Technology

[0002] In the design of automotive chassis braking systems, pedal feel is a crucial performance evaluation method. It reflects the feedback the brake pedal provides to the driver during braking. Therefore, testing the brake pedal feel through experimental methods is necessary.

[0003] In related technologies, before mass production, the brake pedal feel of a vehicle needs to be tested. Previously, brake pedal feel was mostly measured through subjective evaluation of actual vehicles. When personnel stepped on the brake pedal of a vehicle braking test device to test the pedal feel, there was a lack of surrounding references, resulting in a perception that was far removed from reality, affecting the personnel's understanding of the actual pedal feel and the effectiveness of the pedal feel test. Furthermore, whole-vehicle testing is costly, time-consuming, and difficult to achieve in the early stages of product development. Currently, there is a lack of methods for testing on a test bench to conduct early testing of automotive pedal feel, avoid design problems, and shorten the development cycle. Summary of the Invention

[0004] To address the aforementioned problems in the existing technology, this invention provides a test device and method for testing the pedal feel of a passenger vehicle brake pedal. This method enables automatic testing of brake pedal feel on the test device, while also taking into account the driver's subjective evaluation. Furthermore, the automatic data processing improves the efficiency of test data processing and reduces test costs.

[0005] The objective of this invention is achieved through the following technical solution:

[0006] As a first aspect of the present invention, a pedal feel testing device for a passenger vehicle brake pedal is provided, comprising a fixed base, a movable base, an adjustable seat support, a tension / compression actuator, a booster bracket, and a load braking unit; the booster bracket and the load braking unit are mounted on the fixed base; the booster is mounted on the fixed base via the booster bracket; the movable base can slide laterally relative to the fixed base to switch between an objective testing position and a subjective evaluation position; the adjustable seat support is mounted on the movable base; the tension / compression actuator is fixed on the movable base and located to the side of the adjustable seat support, and a tension / compression sensor and a linear displacement sensor are mounted on the tension / compression actuator.

[0007] Furthermore, a hydraulic sensor is installed on the load braking unit.

[0008] Furthermore, it also includes a slide rail, which is fixed to the ground, and the movable base is slidably connected to the slide rail via a slider.

[0009] Furthermore, the booster bracket is hinged to the fixed base by a pin.

[0010] Furthermore, the tension / compression actuator is mounted on a fixed base via an actuator bracket.

[0011] Furthermore, the objective test position refers to the test position when the tension / compression actuator acts on the booster, and the subjective evaluation position refers to the test position when the car seat acts on the load braking unit.

[0012] Furthermore, it also includes guardrails, which are fixed to the movable base and are respectively set behind the adjustable seat support and on the outside of the tension / compression actuator.

[0013] As a second aspect of the present invention, a test method for a brake pedal feel testing device for a passenger vehicle is provided, comprising the following steps:

[0014] Step 1: Build the pedal feel test device for the passenger vehicle brake pedal and arrange the sensors.

[0015] Step 2: Switch the test apparatus to the objective test position and adjust it to the initial test state;

[0016] Step 3: Conduct a brake pedal feel test and obtain test data:

[0017] Operating condition 1. Control the tension-compression actuator to push the brake pedal to the full stroke s of the brake pedal, control the pushing speed to v1, hold for time t, and then control the tension-compression actuator to return to the initial position at a speed of v1.

[0018] Operating condition 2. Control the tension-compression actuator to push the brake pedal to the stroke s, control the pushing speed to v2, hold for time t, and then control the tension-compression actuator to return to the initial position at a speed of v2;

[0019] Condition 3. Switch the test device to the subjective evaluation position. The driver depresses the brake pedal at a certain speed to the maximum travel, holds it for time t, and then releases it.

[0020] During the above-mentioned working condition test, the brake hydraulic pressure of the tension-compression actuator, the displacement of the brake pedal, the pedal force of the brake pedal, and the braking pedal depressing speed were collected simultaneously.

[0021] Step 4: Automatic processing of pedal feel test data and graphical display of test results: Calculate the response time of brake hydraulic pressure based on the data of brake hydraulic pressure and brake pedal displacement over time for the four electric brake cylinders, and automatically select and generate graphical displays of the collected data.

[0022] Furthermore, in step four, the graphical representation is as follows: the horizontal axis of the image represents the brake pedal displacement, and the scale is linear; the vertical axis of the image represents the brake hydraulic pressure of the four electric brake cylinders, and the scale is linear.

[0023] Furthermore, in step four, the graphical representation is as follows: the horizontal axis of the image represents the pedal force, and the scale is linear; the vertical axis represents the braking hydraulic pressure of the four brake wheel cylinders, and the scale is linear.

[0024] The present invention has the following beneficial effects:

[0025] This invention provides a testing device and method for testing the pedal feel of a passenger vehicle brake pedal, involving the construction of a test bench, the installation of test samples, the arrangement of sensors, the testing scheme, and the acquisition of test data. Through reasonable bench construction, sample installation, and sensor arrangement, the actual position of the vehicle pedal can be reproduced, improving the testing accuracy and enabling the switching between objective testing and subjective evaluation of brake pedal feel. Through reasonable testing methods, scientific and effective testing and evaluation of brake pedal feel can be achieved, while simultaneously enabling the comparison of objective data and subjective evaluation test results.

[0026] The test method of this invention automatically processes test data, including the automatic generation and presentation of pedal feel test curves. Through automatic calculation and coordinate transformation, it can realize the relationship between braking displacement and braking hydraulic pressure, and the relationship between braking pedal force and braking displacement. Testers can intuitively grasp the test information and improve processing efficiency. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of the pedal feel test device for a passenger vehicle brake pedal according to Embodiment 1 of the present invention;

[0029] Figure 2 This is a flowchart of a method for testing the pedal feel of a passenger vehicle brake pedal according to Embodiment 2 of the present invention;

[0030] In the picture:

[0031] 1-Fixed base; 2-Moving base; 3-Slide rail; 4-Adjustable seat support; 5-Car seat; 6-Actuator bracket; 7-Pull-compression actuator; 8-Guard rail; 9-Booster bracket; 10-Load braking unit. Detailed Implementation

[0032] To clearly illustrate the technical features of this solution, the invention will be described in detail below through specific embodiments and in conjunction with the accompanying drawings. The following disclosure provides many different embodiments or examples for implementing different structures of the invention. To simplify the disclosure of the invention, components and arrangements of specific examples are described below. Furthermore, reference numerals and / or letters may be repeated in different examples. This repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. It should be noted that the components illustrated in the drawings are not necessarily drawn to scale. Descriptions of well-known components and processing techniques and processes are omitted to avoid unnecessarily limiting the invention. Terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0033] Example 1

[0034] like Figure 1As shown, a pedal feel testing device for a passenger vehicle brake pedal includes a fixed base 1, a movable base 2, a slide rail 3, an adjustable seat support 4, a car seat 5, an actuator bracket 6, a tension / compression actuator 7, a guardrail 8, a booster bracket 9, and a load braking unit 10. The booster bracket 9 and the load braking unit 10 are mounted on the fixed base 1, and a hydraulic sensor can be installed on the load braking unit 10 according to testing requirements. The booster is mounted on the booster bracket 9, and the booster bracket 9 is hinged to the fixed base 1 by a pin and can rotate relative to the fixed base 1. The slide rail 3 is fixed... The mobile base 2 is fixed to the ground and is slidably connected to the slide rail 3 via a slider. It slides laterally relative to the fixed base 2 via the slide rail to switch between objective test position and subjective evaluation position. The slide rail is equipped with a limiting structure to limit the movement of the mobile base 2. The adjustable seat support 4 is installed on the mobile base 2, and the car seat 5 is fixed on the adjustable seat support 4. The actuator bracket 6 is fixed on the mobile base 2 and located to the side of the adjustable seat support 4. The tension and compression actuator 7 is installed on the actuator bracket 6, and tension and compression sensors and linear displacement sensors are installed on the actuator 7.

[0035] The objective test position refers to the test position when the tension / compression actuator acts on the booster, and the subjective evaluation position refers to the test position when the car seat 5 acts on the load braking unit. This arrangement can simulate the installation scheme of a real vehicle and realize the switching between objective testing and subjective evaluation.

[0036] Example 2

[0037] like Figure 2 As shown, a method for testing the pedal feel of a passenger vehicle brake pedal includes the following steps:

[0038] Step 1: Construct the pedal feel test device described in Example 1 and arrange the sensors:

[0039] A booster bracket 9 and a load braking unit 10 are mounted on a fixed base 1. A hydraulic sensor can be installed on the load braking unit 10 according to test requirements. The booster sample is mounted on the booster bracket 9, which rotates via a hinge pin. A movable base 2 is mounted on a slide rail 3 via a slider, allowing for linear sliding and limiting on the slide rail. An adjustable seat support 4 is mounted on the movable base 2, and a car seat 5 is mounted on the seat support. An actuator bracket 6 is also mounted on the movable base 2, and a tension / compression actuator 7 is mounted on the actuator bracket. Tension / compression sensors and linear displacement sensors are installed on the actuator 7. This arrangement can simulate the installation scheme of a real vehicle and allows for switching between objective testing and subjective evaluation. Guardrails are fixed to the movable base 2, located behind the adjustable seat support 4 and outside the tension / compression actuator 7.

[0040] Step 2: Switch the test setup to the objective test position and adjust it to the initial test state:

[0041] Adjust the position of the movable base 2 so that the actuator 7 corresponds to the booster position, i.e. the objective test position; zero each sensor, adjust the input force at the pedal (i.e. the booster sample push rod) to zero, vent the brake system test sample, and the system vents the air. This is the initial state of the test.

[0042] Step 3: Conduct a brake pedal feel test and obtain test data:

[0043] Inspect the condition of the samples (booster, brake pedal, and brake). If no abnormalities are found, begin the operational condition test. The operational condition settings should include the moving speed of the tension / compression actuator, the displacement of the tension / compression actuator, the holding time of the tension / compression actuator, the selection of the acquisition signal, and the setting of the sampling frequency. The test sampling frequency should not be lower than 1000Hz. Specific test conditions are as follows:

[0044] Operating Condition 1: The tension-compression actuator is controlled by the program to push the brake pedal to the stroke s (usually s is the full stroke of the brake pedal, which can be set according to the test requirements). The pushing speed is controlled to v1. After holding for a time t, the tension-compression actuator is controlled to return to the initial position at a speed of v1.

[0045] Operating Condition 2: The program controls the tension-compression actuator to push the brake pedal to the stroke s, and the pushing speed is controlled to v2. After holding for a time t, the tension-compression actuator is controlled to return to the initial position at a speed of v2.

[0046] Condition 3: Switch the test device to the subjective evaluation position. The driver depresses the brake pedal at a certain speed to its maximum travel, holds it for time t, and then releases it.

[0047] During the above-mentioned working condition test, the data acquisition module synchronously collected status information such as the brake hydraulic pressure of the tension-compression actuator, the displacement of the brake pedal, the pedal force of the brake pedal, and the braking pedal depressing speed.

[0048] Step 4: Automatic processing of pedal feel test data and graphical display of test results:

[0049] The response time of the brake hydraulic pressure can be calculated based on the data of the brake hydraulic pressure of the four electric brake cylinders and the change of brake pedal displacement over time. The collected data can be automatically selected and a graphic display can be generated.

[0050] Graphical display method 1: The horizontal axis of the image represents the brake pedal displacement, with a linear scale; the vertical axis of the image represents the brake hydraulic pressure of the four electric brake cylinders, with a linear scale; information such as brake pedal travel and brake pedal speed can be displayed in the image.

[0051] The system automatically generates images under three operating conditions (condition 1, condition 2, and condition 3) and compares the differences in the curves.

[0052] Graphical display method two: The horizontal axis of the image can be switched to pedal force, with a linear scale; at this time, the vertical axis is the braking hydraulic pressure of the four brake wheel cylinders, with a linear scale.

[0053] The graphic display will automatically change when switching.

[0054] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A test method for a test device for testing the pedal feel of a passenger vehicle brake pedal, characterized in that, The pedal feel testing device includes a fixed base, a movable base, an adjustable seat support, a tension / compression actuator, a booster bracket, and a load braking unit. The booster bracket and the load braking unit are mounted on the fixed base. The booster is mounted on the fixed base via the booster bracket. The movable base slides laterally relative to the fixed base to switch between objective testing positions and subjective evaluation positions. The adjustable seat support is mounted on the movable base. The tension / compression actuator is fixed on the movable base and located to the side of the adjustable seat support. Tension / compression sensors and linear displacement sensors are mounted on the tension / compression actuator. The experimental method includes the following steps: Step 1: Build the pedal feel test device for the passenger vehicle brake pedal and arrange the sensors. Step 2: Switch the test apparatus to the objective test position and adjust it to the initial test state; Step 3: Conduct a brake pedal feel test and obtain test data: Operating condition 1. Control the tension-compression actuator to push the brake pedal to the full stroke s of the brake pedal, control the pushing speed to v1, hold for time t, and then control the tension-compression actuator to return to the initial position at a speed of v1. Operating condition 2. Control the tension-compression actuator to push the brake pedal to the stroke s, control the pushing speed to v2, hold for time t, and then control the tension-compression actuator to return to the initial position at a speed of v2; Condition 3. Switch the test device to the subjective evaluation position. The driver depresses the brake pedal at a certain speed to the maximum travel, holds it for time t, and then releases it. During the above-mentioned working condition test, the brake hydraulic pressure of the tension-compression actuator, the displacement of the brake pedal, the pedal force of the brake pedal, and the braking pedal depressing speed were collected simultaneously. Step 4: Automatic processing of pedal feel test data and graphical display of test results: Calculate the response time of brake hydraulic pressure based on the data of brake hydraulic pressure and brake pedal displacement over time for the four electric brake cylinders, and automatically select and generate graphical displays of the collected data.

2. The test method of the pedal feel test device for a passenger vehicle brake pedal as described in claim 1, characterized in that, A hydraulic sensor is installed on the load braking unit.

3. The test method of the pedal feel test device for a passenger vehicle brake pedal as described in claim 1, characterized in that, The pedal feel testing device also includes a slide rail, which is fixed to the ground, and a movable base is slidably connected to the slide rail via a slider.

4. The test method of the pedal feel test device for a passenger vehicle brake pedal as described in claim 1, characterized in that, The booster bracket is hinged to the fixed base by a pin.

5. The test method of the pedal feel test device for a passenger vehicle brake pedal as described in claim 1, characterized in that, The tension / compression actuator is mounted on a fixed base via an actuator bracket.

6. The test method of the pedal feel test device for a passenger vehicle brake pedal as described in claim 1, characterized in that, The objective test position refers to the test position when the tension / compression actuator acts on the booster, and the subjective evaluation position refers to the test position when the car seat acts on the load braking unit.

7. The test method of the pedal feel test device for a passenger vehicle brake pedal as described in claim 1, characterized in that, The pedal feel test device also includes a guardrail, which is fixed on the movable base and is respectively set behind the adjustable seat support and on the outside of the tension / compression actuator.

8. The test method of the pedal feel test device for a passenger vehicle brake pedal as described in claim 1, characterized in that, In step four, the graphic display is as follows: the horizontal axis of the image represents the brake pedal displacement, and the scale is linear; the vertical axis of the image represents the brake hydraulic pressure of the four electric brake cylinders, and the scale is linear.

9. The test method of the pedal feel test device for a passenger vehicle brake pedal as described in claim 1, characterized in that, In step four, the graphical representation is as follows: the horizontal axis of the image represents the pedal force, and the scale is linear; the vertical axis represents the braking hydraulic pressure of the four brake wheel cylinders, and the scale is linear.

Images