System and method for bidirectionally converting torque signal

Abstract

The invention discloses a two-way conversion torque signal which comprises a two-way torque sensor, the two-way torque sensor is used for obtaining and detecting a torque signal acting on a steering wheel by a driver in real time, and a preprocessing module is used for adjusting the torque signal detected in real time into a denoised amplified torque signal. The compensation processing module is used for adjusting the amplified torque signal into a compensation torque signal, the EPS controller determines a power-assisted torque signal needing to be applied according to the vehicle speed signal and the compensation torque signal through preset power-assisted characteristics and a control strategy, and the motor is used for receiving the power-assisted torque signal and controlling the power-assisted torque signal to output the current power-assisted torque. When the power assisting device is used, the torque signal detected in real time is obtained, then the torque signal is sequentially subjected to preprocessing and compensation processing, the processed torque signal is output to the EPS controller, the EPS controller controls the driving motor to generate the corresponding power assisting torque, and the driving comfort and safety can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of automobile power steering control, and in particular to a system and method for bidirectional conversion of torque signals. Background Art

[0002] The relationship between the EPS (electric power steering system) controller and the torque signal is close, and the torque signal plays a vital role in the EPS system. The torque signal is obtained by the driver of the vehicle when turning the steering wheel forward or backward, so that the obtained torque signal has a distinction between forward and reverse. In the prior art, the vehicle steering output is assisted by the obtained torque signal, such as the patent "A bidirectional conversion module and a vehicle power steering system" with the publication number CN112960036A. The application is to design a bidirectional conversion module between the torque sensor and the EPS controller, and distinguish the direction and size of the obtained torque signal through the bidirectional conversion module. The following defects exist in the use of the application: the circuit structure of the designed bidirectional conversion module is complex, and there are problems of low conversion accuracy and slow speed; in addition, in the process of using the torque sensor to obtain the torque signal, the zero point and full scale offset caused by the physical deformation of the strain gauge structure of the torque sensor brings about voltage deviation, resulting in low acquisition accuracy, and data deviation occurs at the initial acquisition end of the real-time detection of the torque signal, which ultimately leads to deviation in the output torque of the control motor, and the operation application effect is poor. Summary of the invention

[0003] The object of the present invention is to provide a system and method for bidirectional conversion of torque signals, so as to solve the problems of poor accuracy and poor application effect in controlling the output torque of a motor in the prior art.

[0004] The purpose of the present invention can be achieved by the following technical solutions:

[0005] A system for bidirectionally converting a torque signal, comprising:

[0006] Bidirectional torque sensor, used to obtain real-time detection of the torque signal applied by the driver on the steering wheel;

[0007] A preprocessing module, whose input end is connected to the output end of the bidirectional torque sensor and is used to adjust the real-time detected torque signal into a denoised amplified torque signal;

[0008] a compensation processing module, whose input end is connected to the output end of the preprocessing module and is used to adjust the amplified torque signal to a compensation torque signal;

[0009] An EPS controller, whose input end is connected to the compensation processing module and the output end of the vehicle speed sensor, the vehicle speed sensor is used to obtain a vehicle speed signal for real-time detection of the current vehicle, and the EPS controller determines the power assist torque signal to be applied according to the vehicle speed signal and the compensation torque signal and through a preset power assist characteristic and control strategy;

[0010] The electric motor has an input end connected to the output end of the EPS controller and is used to receive the assist torque signal and control the motor to output the current assist torque.

[0011] As a further solution of the present invention: the torque signal detected in real time includes torque direction and voltage magnitude information.

[0012] As a further solution of the present invention: the preprocessing module includes an amplifier circuit and a filter circuit which are sequentially arranged between the bidirectional torque sensor and the compensation processing module, the amplifier circuit is used to amplify and output the weak voltage signal in the real-time detected torque signal according to a set amplification ratio coefficient, and the filter circuit is used to remove high-frequency noise and interference in the real-time detected torque signal, and output a denoised amplified torque signal.

[0013] As a further solution of the present invention: the compensation processing module includes a linear compensation circuit arranged between the preprocessing module and the EPS controller, and the linear compensation circuit obtains a compensation torque signal Y through a compensation calculation formula Y=mX+b; wherein m is a preset compensation parameter, and m is a natural number greater than 0; b is a preset intercept offset, and b is a natural number greater than 0; X is a voltage magnitude information data value in the amplified torque signal.

[0014] A method for bidirectionally converting a torque signal comprises the following steps:

[0015] S1, obtaining a real-time detection torque signal of the driver acting on the steering wheel through a bidirectional torque sensor;

[0016] S2. Outputting a denoised amplified torque signal through a preprocessing module according to the real-time detected torque signal;

[0017] S3, outputting a compensation torque signal through a compensation processing module according to the amplified torque signal;

[0018] S4, obtaining a real-time detection signal of the current vehicle speed through a vehicle speed sensor, and according to the vehicle speed signal and the compensation signal, the EPS controller determines the power assist torque signal to be applied through a preset power assist characteristic and control strategy;

[0019] S5. Use the assist torque signal to control the motor to output the current assist torque.

[0020] As a further solution of the present invention: when obtaining the real-time detected torque signal in step S1, the strain gauge structure of the bidirectional torque sensor is pasted on the steering shaft connected to the integrated steering wheel structure, and the deformation of the strain gauge structure is used to monitor the change in its resistance value to obtain the real-time detected torque signal including torque direction and voltage magnitude information.

[0021] As a further solution of the present invention: when the denoised amplified torque signal is output through the preprocessing module in step S2, the real-time detected torque signal is processed in sequence through the amplifier circuit and the filter circuit included in the preprocessing module to obtain the output denoised amplified torque signal.

[0022] As a further solution of the present invention: when the compensation torque signal is output through the compensation processing module in step S3, the linear compensation circuit included in the compensation processing module obtains the compensation torque signal Y through the compensation calculation formula Y=mX+b; wherein, m is a preset compensation parameter, and m is a natural number greater than 0; b is a preset intercept offset, and b is a natural number greater than 0; X is the voltage magnitude information data value in the amplified torque signal.

[0023] As a further solution of the present invention: when the assist torque signal to be applied is determined in step S4, the EPS controller has a closed-loop feedback mechanism, which can monitor the actual output torque of the motor in real time, and compare and adjust the actual output torque with the assist torque signal to ensure the accuracy and stability of the assist torque signal.

[0024] As a further solution of the present invention: when the assist torque signal is used to control the motor to output the current assist torque in step S5, the motor is a motor with bidirectional driving capability, and the assist torque signal sends corresponding instructions to the motor to control the motor to generate the required current assist torque in the forward or reverse direction.

[0025] Beneficial effects of the present invention:

[0026] (1) When the present application is used, a real-time detected torque signal can be obtained through a bidirectional torque sensor, so that the current positive or reverse torque can be distinguished through the set bidirectional torque sensor, and the real-time detected voltage magnitude information is adjusted by a preprocessing module, which helps to ensure that the amplified torque signal transmitted to the compensation processing module is accurate and reliable. The amplified torque signal is adjusted by the compensation processing module, and then the voltage deviation can be eliminated. The compensated torque signal is output to the EPS controller. Based on the compensation torque signal and the vehicle speed signal, the EPS controller determines the assist torque signal of the motor, and then controls the rotation direction and assist current of the motor through the assist torque signal, drives the motor to generate the corresponding assist torque, and helps to improve driving comfort and safety;

[0027] (2) The present application has a simplified design, replacing the design idea of ​​using a bidirectional conversion module circuit for differentiation, thereby solving the problems of low conversion accuracy and slow speed;

[0028] (3) The strain gauge structure of the bidirectional torque sensor of the present application may cause zero point and full scale offset due to physical deformation during use, thereby generating voltage deviation and affecting the acquisition accuracy. The present application adopts a compensation processing module for adjustment, which can effectively improve the measurement accuracy and stability of the bidirectional torque sensor and meet the needs of practical applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention will be further described below in conjunction with the accompanying drawings.

[0030] Figure 1 It is a framework diagram of a system for bidirectionally converting torque signals of the present invention;

[0031] Figure 2 It is a linear schematic diagram of a torque signal detected in real time by a bidirectional torque sensor of a system for bidirectionally converting torque signals of the present invention;

[0032] Figure 3 A linear schematic diagram of a compensation torque signal determined by a compensation processing module of a system for bidirectional conversion of torque signals according to the present invention;

[0033] Figure 4 It is a flow chart of a method for bidirectional conversion of torque signals of the present invention.

[0034] In the figure: 10, bidirectional torque sensor; 20, preprocessing module; 30, compensation processing module; 40, EPS controller; 50, vehicle speed sensor; 60, electric motor. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] In the description of the present invention, it should be understood that the terms indicating orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention; in the description of the present invention, the meaning of "multiple" and "several" is at least two, for example two, three, etc., unless otherwise clearly and specifically defined.

[0037] See also Figure 1 As shown, the present invention is a system for bidirectional conversion of torque signals, including a bidirectional torque sensor 10, a preprocessing module 20, a compensation processing module 30, an EPS controller 40 and a motor 60. The bidirectional torque sensor 10 is used to obtain a real-time detection of a torque signal applied by a driver on a steering wheel. The input end of the preprocessing module 20 is connected to the output end of the bidirectional torque sensor 10, and is used to adjust the real-time detected torque signal to a denoised amplified torque signal. The input end of the compensation processing module 30 is connected to the output end of the preprocessing module 20, and is used to adjust the amplified torque signal to a compensated torque signal. The input end of the EPS controller 40 is connected to the output end of the compensation processing module 30 and a vehicle speed sensor 50. The vehicle speed sensor 50 is used to obtain a real-time detection of a vehicle speed signal of the current vehicle. The EPS controller 40 determines the power-assist torque signal to be applied according to the vehicle speed signal and the compensation torque signal, and through a preset power-assist characteristic and a control strategy. The input end of the motor 60 is connected to the output end of the EPS controller 40, and is used to receive the power-assist torque signal and control it to output the current power-assist torque.

[0038] When the system for bidirectional conversion of torque signals of the present application is used, the real-time detected torque signal can be obtained through the bidirectional torque sensor 10. The real-time detected torque signal includes torque direction and voltage magnitude information, so that the present application can distinguish the current positive or reverse torque only by setting the bidirectional torque sensor 10, and the real-time detected voltage magnitude information is adjusted by the preprocessing module 20, which helps to ensure that the amplified torque signal transmitted to the compensation processing module 30 is accurate and reliable. The amplified torque signal is adjusted by the compensation processing module 30. The strain gauge structure of the bidirectional torque sensor 10 will cause zero point and full scale offset due to physical deformation during use, thereby generating Voltage deviation affects the acquisition accuracy. The present application adopts a compensation processing module 30 to compensate the torque signal initially obtained in real-time detection, thereby eliminating the voltage deviation, and can effectively improve the measurement accuracy and stability of the bidirectional torque sensor 10 to meet the needs of practical applications; so that the compensated torque signal is output to the EPS controller 40. Based on the compensated torque signal and the vehicle speed signal, the EPS controller 40 will determine the assist torque signal of the motor 60, and then control the rotation direction and assist current of the motor 60 through the assist torque signal, and drive the motor 60 to generate corresponding assist torque, which helps to improve driving comfort and safety.

[0039] In this specific embodiment, the torque signal detected in real time includes torque direction and voltage magnitude information. When the bidirectional torque sensor 10 is used to obtain the information, when the bidirectional torque sensor 10 is subjected to a positive torque, the strain gauge structure on the steering shaft will produce a corresponding positive strain, resulting in an increase in the resistance value of the strain gauge structure; on the contrary, when the bidirectional torque sensor 10 is subjected to a reverse torque, the strain gauge structure on the steering shaft will produce a corresponding reverse strain, resulting in a decrease (or increase) in the resistance value of the strain gauge structure; therefore, the voltage magnitude information can be obtained through the bidirectional torque sensor 10; the voltage magnitude information obtained by the bidirectional torque sensor 10 is directional, and its directionality can be detected to obtain the torque direction.

[0040] like Figure 2 As shown, the present application can distinguish the current forward or reverse torque only by setting up a bidirectional torque sensor 10. The bidirectional torque sensor 10 can form a linearly proportional correspondence between the torque size and the voltage signal. The design is simplified, replacing the design idea of ​​using a bidirectional conversion module circuit for distinction, thereby solving the problems of low conversion accuracy and slow speed.

[0041] In this specific embodiment, the preprocessing module 20 includes an amplifier circuit and a filter circuit which are sequentially arranged between the bidirectional torque sensor 10 and the compensation processing module 30. The amplifier circuit is used to amplify and output the weak voltage signal in the real-time detected torque signal according to a set amplification ratio coefficient, and the filter circuit is used to remove high-frequency noise and interference in the real-time detected torque signal, and output a denoised amplified torque signal; the use of the preprocessing module 20 in this application can ensure that the signal transmitted to the compensation processing module 30 is accurate and reliable, thereby improving the control accuracy.

[0042] In this specific implementation, the compensation processing module 30 includes a linear compensation circuit arranged between the preprocessing module 20 and the EPS controller 40, and the linear compensation circuit obtains the compensated torque signal Y through the compensation calculation formula Y=mX+b; wherein, m is a preset compensation parameter, and m is a natural number greater than 0; b is a preset intercept offset, and b is a natural number greater than 0; X is the voltage magnitude information data value in the amplified torque signal; the strain gauge structure of the bidirectional torque sensor 10 will cause zero point and full scale offset due to physical deformation during use, thereby generating voltage deviation, affecting the acquisition accuracy. The present application adopts the compensation processing module 30 for adjustment, and the linear relationship between the adjusted torque magnitude and the voltage signal is as follows: Figure 3 As shown, the compensation torque signal Y can be automatically adjusted. It should be understood that the preset compensation parameter m is the linear slope between the torque and the voltage, and the preset intercept offset b is used to adjust the offset of the compensation torque signal Y.

[0043] In practical applications, the values ​​of the preset compensation parameter m and the preset intercept offset b are usually obtained through experimental measurement and data analysis; the specific process is as follows: several known torque values ​​are selected as test points within the measurement range of the bidirectional torque sensor 10; for each test point, the original output signal X of the bidirectional torque sensor 10 is measured, and the corresponding actual torque value is recorded; through data analysis, the least squares method or other linear regression methods are used to fit the experimental data, and the optimal values ​​of the preset compensation parameter m and the preset intercept offset b are calculated, thereby obtaining the optimal linear compensation parameters; so as to facilitate the application of the values ​​of the preset compensation parameter m and the preset intercept offset b to the compensation calculation formula, so as to realize automatic compensation adjustment of the output signal of the bidirectional torque sensor 10.

[0044] Combination Figure 4 As shown, the present invention also provides a method for bidirectional conversion of torque signals, comprising the following steps:

[0045] S1. Obtain real-time detection of the torque signal applied by the driver on the steering wheel through the bidirectional torque sensor 10; when obtaining the real-time detected torque signal, the strain gauge structure of the bidirectional torque sensor 10 is pasted on the steering shaft connected to the integrated structure of the steering wheel, and the deformation of the strain gauge structure is used to monitor the change of its resistance value to obtain the real-time detected torque signal including torque direction and voltage magnitude information.

[0046] S2. According to the real-time detected torque signal, a denoised amplified torque signal is output through the preprocessing module 20; when the denoised amplified torque signal is output through the preprocessing module 20, the real-time detected torque signal is processed in sequence through the amplifying circuit and the filtering circuit included in the preprocessing module 20 to obtain an output denoised amplified torque signal.

[0047] S3. According to the amplified torque signal, a compensation torque signal is output through the compensation processing module 30; when the compensation torque signal is output through the compensation processing module 30, the linear compensation circuit included in the compensation processing module 30 obtains the compensation torque signal Y through the compensation calculation formula Y=mX+b; wherein, m is a preset compensation parameter, and m is a natural number greater than 0; b is a preset intercept offset, and b is a natural number greater than 0; X is the voltage magnitude information data value in the amplified torque signal.

[0048] S4. The vehicle speed sensor 50 is used to obtain a real-time detection signal of the current vehicle speed. According to the vehicle speed signal and the compensation signal, the EPS controller 40 determines the assist torque signal to be applied through the preset assist characteristics and control strategy. When determining the assist torque signal to be applied, the EPS controller 40 has a closed-loop feedback mechanism, which can monitor the actual output torque of the motor 60 in real time, and compare and adjust the actual output torque with the assist torque signal to ensure the accuracy and stability of the assist torque signal.

[0049] S5. Use the assist torque signal to control the motor 60 to output the current assist torque; when using the assist torque signal to control the motor 60 to output the current assist torque, the motor 60 is a motor 60 with bidirectional driving capability, and the assist torque signal sends corresponding instructions to the motor 60 to control the motor 60 to generate the required current assist torque in the forward or reverse direction.

[0050] The method of bidirectional conversion of torque signals in the present application has the same working principle as that in the above-mentioned system, and will not be described in detail here.

[0051] It should be understood that, based on the same inventive concept, an embodiment of the present application also provides a computer-readable storage medium, which includes a program. When the program is called by a processor, the processor implements the above method of bidirectional conversion of torque signals.

[0052] It should be understood that all or part of the steps of implementing the above method embodiments can be completed by hardware related to program instructions, and the above program can be stored in a computer-readable storage medium. When the program code is called by a processor, the processor is used to execute the method executed in the above method embodiment. The embodiment of the present invention does not limit the form and number of the memory and the processor. For example, the memory can be a CPU or other processor that can call a program, and the memory can be a read-only memory (ROM), a random access memory (RAM), a disk or an optical disk, and other media that can store program codes.

[0053] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A system for bidirectional conversion of torque signals, characterized in that: include: A bidirectional torque sensor (10) is used to obtain a real-time detection signal of the torque applied by the driver to the steering wheel; A preprocessing module (20), whose input end is connected to the output end of the bidirectional torque sensor (10) and is used to adjust the real-time detected torque signal into a de-noised amplified torque signal; A compensation processing module (30), whose input end is connected to the output end of the preprocessing module (20) and is used to adjust the amplified torque signal into a compensation torque signal; An EPS controller (40), whose input end is connected to the compensation processing module (30) and the output end of a vehicle speed sensor (50), wherein the vehicle speed sensor (50) is used to obtain a vehicle speed signal for real-time detection of the current vehicle speed, and the EPS controller (40) determines the power assist torque signal to be applied according to the vehicle speed signal and the compensation torque signal and through a preset power assist characteristic and control strategy; The electric motor (60) has an input end connected to the output end of the EPS controller (40) and is used to receive the assist torque signal and control the motor to output the current assist torque.

2. A system for bidirectionally converting torque signals according to claim 1, characterized in that: The torque signal detected in real time includes torque direction and voltage magnitude information.

3. A system for bidirectional conversion of torque signals according to claim 2, characterized in that: The preprocessing module (20) comprises an amplifier circuit and a filter circuit which are sequentially arranged between the bidirectional torque sensor (10) and the compensation processing module (30), wherein the amplifier circuit is used to amplify and output the weak voltage signal in the real-time detected torque signal according to a set amplification ratio coefficient, and the filter circuit is used to remove high-frequency noise and interference in the real-time detected torque signal and output a denoised amplified torque signal.

4. A system for bidirectionally converting torque signals according to claim 3, characterized in that: The compensation processing module (30) comprises a linear compensation circuit arranged between the preprocessing module (20) and the EPS controller (40), and the linear compensation circuit obtains a compensation torque signal Y through a compensation calculation formula Y=mX+b; wherein m is a preset compensation parameter, and m is a natural number greater than 0; b is a preset intercept offset, and b is a natural number greater than 0; and X is a voltage magnitude information data value in the amplified torque signal.

5. A method for bidirectional conversion of torque signals, characterized in that: The following steps are involved: S1, obtaining a torque signal of a driver acting on a steering wheel by a bidirectional torque sensor (10) in real time; S2, outputting a denoised amplified torque signal through a preprocessing module (20) according to the torque signal detected in real time; S3, outputting a compensation torque signal through a compensation processing module (30) according to the amplified torque signal; S4, obtaining a vehicle speed signal of the current vehicle in real time through a vehicle speed sensor (50), and according to the vehicle speed signal and the compensation signal, the EPS controller (40) determines the power assist torque signal to be applied through a preset power assist characteristic and control strategy; S5. Using the assist torque signal to control the motor (60) to output the current assist torque.

6. A method for bidirectional conversion of torque signals according to claim 5, characterized in that: When obtaining the real-time detected torque signal in step S1, the strain gauge structure of the bidirectional torque sensor (10) is pasted on a steering shaft connected to the integrated steering wheel structure, and the deformation of the strain gauge structure is used to monitor the change in its resistance value to obtain the real-time detected torque signal including torque direction and voltage magnitude information.

7. The method for bidirectional conversion of torque signals according to claim 6, characterized in that: When the denoised amplified torque signal is output through the preprocessing module (20) in step S2, the real-time detected torque signal is processed in sequence through the amplifier circuit and the filter circuit included in the preprocessing module (20) to obtain the output denoised amplified torque signal.

8. The method for bidirectional conversion of torque signals according to claim 7, characterized in that: When the compensation torque signal is outputted by the compensation processing module (30) in step S3, the linear compensation circuit included in the compensation processing module (30) obtains the compensation torque signal Y through the compensation calculation formula Y=mX+b; wherein m is a preset compensation parameter, and m is a natural number greater than 0; b is a preset intercept offset, and b is a natural number greater than 0; and X is the voltage magnitude information data value in the amplified torque signal.

9. The method for bidirectional conversion of torque signals according to claim 8, characterized in that: When the assist torque signal to be applied is determined in step S4, the EPS controller (40) has a closed-loop feedback mechanism, which can monitor the actual output torque of the motor (60) in real time, and compare and adjust the actual output torque with the assist torque signal to ensure the accuracy and stability of the assist torque signal.

10. The method for bidirectional conversion of torque signal according to claim 9, characterized in that: When the assist torque signal is used to control the motor (60) to output the current assist torque in step S5, the motor (60) is a motor (60) with bidirectional driving capability, and the assist torque signal sends a corresponding instruction to the motor (60) to control the motor (60) to generate the required current assist torque in the forward or reverse direction.

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