Steer-by-wire system temperature protection method and system based on multi-modal sensing

Abstract

The invention discloses a steer-by-wire system temperature protection method and system based on multi-mode sensing, and belongs to the technical field of vehicle control, and the method comprises the steps: obtaining the detection temperature of each function module in a steer-by-wire system and the current and rotating speed of a motor; carrying out weighted fusion on the detection temperatures of all the function modules to obtain the temperature of a detection layer of the steer-by-wire system; calculating and determining the predicted layer temperature of the steer-by-wire system according to the current and the rotating speed of the motor; fusing the detection layer temperature and the prediction layer temperature of the steer-by-wire system to obtain a fusion temperature of the steer-by-wire system; and when the fusion temperature is larger than a set first temperature threshold value, the output torque of the steer-by-wire system is limited. Accurate and timely temperature protection of the steer-by-wire system is realized.

Description

Technical Field

[0001] The present disclosure relates to the field of automobile technology, and in particular to a temperature protection method and system for a steer-by-wire system based on multimodal sensing. Background Art

[0002] The steer-by-wire system is a new steering technology that uses electronic signals to transmit the driver's steering intentions and adjust the vehicle's driving state. It is widely used in modern intelligent vehicles. The steer-by-wire system consists of three main components: the steering wheel module, the steering actuator module, and the control unit. The steering wheel module includes components such as the steering wheel torque and angle sensors, and the road sensing motor; the steering actuator module includes components such as the linear displacement sensor, angle sensor, steering motor, and its reduction mechanism. When the steer-by-wire system is subjected to extreme operating conditions for extended periods, its controller will output high current for extended periods, causing a sharp increase in the temperature of the controller, road sensing motor, and steering motor. Failure to identify and implement appropriate protective measures for this temperature rise will reduce the service life of the controller and steering motor, thereby reducing the reliability of the steer-by-wire system.

[0003] The related method mainly monitors the temperature of the power drive module which is the main heat source of the high-power circuit in the wire-controlled steering system, and then controls each power drive module individually according to the detected temperature.

[0004] Since there are multiple functional modules in the steer-by-wire system, each functional module generates heat, causing the temperature of the steer-by-wire system to rise. The power drive module temperature monitored separately in the relevant method cannot reflect the overall temperature status of the steer-by-wire system, which leads to inaccurate temperature control of the steer-by-wire system. Summary of the Invention

[0005] The present disclosure provides a method and system for temperature protection of a steer-by-wire system based on multimodal sensing. The technical solution is as follows: In a first aspect, a temperature protection method for a steer-by-wire system based on multimodal sensing is provided, comprising: Obtain the detected temperature of each functional module in the steer-by-wire system and the current and speed of the motor; Perform weighted fusion on the detection temperatures of all functional modules to obtain the detection layer temperature of the steer-by-wire system; Calculate and determine the predicted layer temperature of the steer-by-wire system based on the current and speed of the motor; The detection layer temperature and the prediction layer temperature of the steer-by-wire system are fused to obtain the fused temperature of the steer-by-wire system; When the fusion temperature is greater than a set first temperature threshold, the output torque of the steer-by-wire system is limited.

[0006] Optionally, obtaining the measured temperature of each functional module in the steer-by-wire system, collecting the installation position of the measured temperature sensor of each functional module and the ambient temperature of the steer-by-wire system; Determine the ambient compensation temperature of the measured temperature of each functional module according to the ambient temperature of the vehicle; Determine the position compensation temperature of each functional module's measured temperature based on the installation position of the temperature sensor that collects the measured temperature of each functional module; The measured temperature, environmental compensation temperature and position compensation temperature of each functional module are added together to obtain the detection temperature of each functional module.

[0007] Optionally, obtaining the confidence level of the temperature sensor detected by each functional module; Calculate the ratio of the confidence of each temperature sensor to the total confidence of all temperature sensors, and use it as the weight of the temperature detected by each functional module collected by each temperature sensor; The detection temperature of all functional modules is weightedly fused using the weight of the detection temperature of each functional module to obtain the detection layer temperature of the wire-controlled steering system.

[0008] Optionally, the copper loss heat generation of the motor winding is calculated and determined based on the current of the motor; According to the motor's rotation speed, calculate and determine the frictional heat generated by the motor's rotation; Calculate the sum of the heat generated by the copper loss of the motor winding and the frictional heat generated by the motor rotation to obtain the comprehensive heat generated by the motor; The comprehensive heat generation and the gearbox conduction heat are weighted and fused, and then added to the initial temperature reference of the steer-by-wire system to obtain the predicted layer temperature of the steer-by-wire system.

[0009] Optionally, calculating an error between a predicted layer temperature and a detected layer temperature of a steer-by-wire system; When the error is greater than the set error threshold, the weight coefficient used in the weighted fusion of the comprehensive heat output and the gearbox conduction heat is updated so that the error between the predicted layer temperature and the detection layer temperature of the wire control steering system obtained using the updated weight coefficient is less than or equal to the set error threshold.

[0010] Optionally, when the fusion temperature is less than or equal to a set first temperature threshold, the steer-by-wire system is controlled to output full power; When the fusion temperature is greater than a set first temperature threshold and less than or equal to a second temperature threshold, calculating a deviation between the fusion temperature and the first temperature threshold, and determining an output torque of the steer-by-wire system based on the deviation and a set first torque reduction amplitude; When the fusion temperature is greater than a set second temperature threshold and less than or equal to a third temperature threshold, calculating a deviation between the fusion temperature and the second temperature threshold, and determining an output torque of the steer-by-wire system based on the deviation and a set second torque reduction amplitude; When the fusion temperature is greater than a set third temperature threshold, the output torque of the steer-by-wire system is determined to be 0.

[0011] Secondly, a temperature protection system for a steer-by-wire system based on multimodal sensing is provided, including: A data acquisition unit, used to obtain the detected temperature of each functional module in the steer-by-wire system and the current and speed of the motor; The detection layer temperature calculation unit is used to perform weighted fusion of the detection temperatures of all functional modules to obtain the detection layer temperature of the steer-by-wire system; A prediction layer temperature calculation unit, configured to calculate and determine the prediction layer temperature of the steer-by-wire system based on the current and speed of the motor; a fusion temperature calculation unit, configured to fuse the detection layer temperature and the prediction layer temperature of the steer-by-wire system to obtain a fusion temperature of the steer-by-wire system; The output torque determination unit is used to limit the output torque of the steer-by-wire system when the fusion temperature is greater than a set first temperature threshold.

[0012] In a third aspect, a computer device is provided, comprising: a processor adapted to execute a computer program; A computer-readable storage medium having a computer program stored therein, wherein when the computer program is executed by the processor, the temperature protection method for a wire-controlled steering system based on multimodal sensing proposed in the first aspect is implemented.

[0013] In a fourth aspect, a computer-readable storage medium is proposed, wherein the computer-readable storage medium stores a computer program, and the computer program is suitable for being loaded by a processor and executing the temperature protection method of the wire-controlled steering system based on multimodal sensing proposed in the first aspect.

[0014] In a fifth aspect, a computer program product is proposed, which includes a computer program. When the computer program is executed by a processor, it implements the temperature protection method of the wire-controlled steering system based on multimodal sensing proposed in the first aspect.

[0015] The technical solutions provided by the embodiments of the present disclosure have the following beneficial effects: The disclosed embodiments provide a temperature protection method and system for a steer-by-wire system based on multimodal sensing. The method obtains the detection temperature of each functional module in the steer-by-wire system, and the current and speed of the motor, and obtains the detection layer temperature of the steer-by-wire system by weighted fusion of the detection temperatures of each functional module; obtains the prediction layer temperature of the steer-by-wire system by the current and speed of the motor; obtains the fusion temperature of the steer-by-wire system by weighted fusion of the detection layer temperature and the prediction layer temperature, and the fusion temperature of the steer-by-wire system is obtained. Since the fusion temperature comprehensively considers the temperature of each functional module and the temperature of the motor, the fusion temperature can accurately reflect the overall temperature state of the steer-by-wire system; and then the output torque of the steer-by-wire system can be controlled according to the fusion temperature; when the fusion temperature is greater than a set first temperature threshold, the output torque of the steer-by-wire system is limited to ensure the safety of the steer-by-wire system. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0017] Figure 1 A flow chart of a temperature protection method for a steer-by-wire system based on multimodal sensing provided in an embodiment of the present disclosure; Figure 2 A block diagram of an application system for a temperature protection method for a steer-by-wire system based on multimodal sensing according to an embodiment of the present disclosure; Figure 3 A torque limit curve diagram provided for an embodiment of the present disclosure. DETAILED DESCRIPTION

[0018] In order to make the objectives, technical solutions and advantages of the present disclosure more clear, the embodiments of the present disclosure will be further described in detail below with reference to the accompanying drawings.

[0019] Before describing in detail the temperature protection method for a steer-by-wire system based on multimodal sensing proposed in an embodiment of the present disclosure, the application scenarios and application systems of the temperature protection method for a steer-by-wire system based on multimodal sensing proposed in an embodiment of the present disclosure are first described.

[0020] First, the application scenario of the temperature protection method of the wire-controlled steering system based on multimodal sensing is explained.

[0021] The steer-by-wire system in intelligent vehicles consists of three main components: the steering wheel module, the steering actuator module, and the control unit. The steering wheel module includes components such as steering wheel torque and angle sensors, and a road-sensing motor. The steering center of mass module includes components such as a linear displacement sensor, an angle sensor, the steering motor, and its reduction mechanism. When a steer-by-wire system is subjected to extreme operating conditions for extended periods, its controller will output high currents for extended periods, causing a sharp rise in temperature of the controller, road-sensing motor, and steering motor. Failure to identify and implement appropriate protective measures for this temperature rise will reduce the service life of the controller and steering motor, ultimately reducing the reliability of the steer-by-wire system.

[0022] The related methods mainly monitor the temperature of the power drive modules, which are the main heat sources of high-power circuits in the steer-by-wire system, individually, and then control each power drive module individually based on the detected temperature. Since the temperature of the power drive modules monitored individually cannot reflect the overall temperature status of the steer-by-wire system, the temperature control of the steer-by-wire system is inaccurate, and the temperature protection effect of the steer-by-wire system is limited.

[0023] The temperature protection method for a steer-by-wire system based on multimodal sensing proposed in the embodiments of the present disclosure is proposed based on this application scenario.

[0024] Next, an application system of the temperature protection method for a steer-by-wire system based on multimodal sensing proposed in an embodiment of the present disclosure is described.

[0025] The temperature protection method for a steer-by-wire system based on multimodal sensing proposed in the embodiments of the present disclosure is applied to the steering control system of an intelligent driving vehicle.

[0026] like Figure 2 As shown, the steering control system includes a wire-controlled steering system, a mechanical steering system, a heat dissipation system, a steering controller (MCU), a temperature acquisition sensor, a current detection sensor, and a speed sensor; wherein the wire-controlled steering system includes a gearbox in the reduction mechanism, a driving motor for steering, and a controller power circuit (ECU power module).

[0027] The cooling system includes a cooling fan and cooling fins; the cooling system is used to dissipate heat for the steer-by-wire system.

[0028] Mechanical steering system, used to provide steering when the steer-by-wire system is turned off.

[0029] The temperature acquisition sensors include multiple ones, which are used to measure the temperature of the drive motor winding module, the ECU power module, the gearbox module and the ambient temperature of the wire-controlled steering system, so as to obtain the actual temperature of the motor winding module, the ECU power module, the gearbox module and the ambient temperature of the wire-controlled steering system.

[0030] Among them, 3×PT100 thin film temperature sensors (temperature resistance 200°C) are used to measure the temperature of the drive motor winding module; SiC MOSFET integrated junction temperature detection is used to measure the temperature of the ECU power module; and infrared array temperature measurement (5×5 pixels, accuracy of ±0.5°C) is used to measure the temperature of the gearbox module.

[0031] The current detection sensor and the speed sensor are used to obtain the current and speed of the drive motor respectively.

[0032] The steering controller (MCU) is used to calculate and determine the detection layer temperature of the steering-by-wire system based on the actual measured temperature of the motor winding module, the actual measured temperature of the ECU power module, the actual measured temperature of the gearbox module, and the ambient temperature of the steering-by-wire system; calculate and determine the prediction layer temperature of the steering-by-wire system based on the current and speed of the motor; fuse the detection layer temperature and the prediction layer temperature of the steering-by-wire system to obtain the fusion temperature of the steering-by-wire system; and control the output torque of the steering-by-wire system based on the fusion temperature of the steering-by-wire system.

[0033] Based on the application scenarios and application systems, combined Figure 1 and Figure 3 , a temperature protection method for a wire-controlled steering system based on multimodal sensing proposed in an embodiment of the present disclosure is described in detail.

[0034] The temperature protection method for a steer-by-wire system based on multimodal sensing proposed in the embodiments of the present disclosure includes: Obtain the detected temperature of each functional module in the steer-by-wire system and the current and speed of the motor; Perform weighted fusion on the detection temperatures of all functional modules to obtain the detection layer temperature of the steer-by-wire system; Calculate and determine the predicted layer temperature of the steer-by-wire system based on the current and speed of the motor; The detection layer temperature and the prediction layer temperature of the steer-by-wire system are fused to obtain the fused temperature of the steer-by-wire system; When the fusion temperature is greater than a set first temperature threshold, the output torque of the steer-by-wire system is limited.

[0035] The acquired detection temperatures of the functional modules include the detection temperature of the drive motor winding module, the detection temperature of the ECU power module, and the detection temperature of the gearbox module.

[0036] In some embodiments, the measured temperature of each functional module in the steer-by-wire system is obtained, the installation position of the measured temperature sensor of each functional module is collected, and the ambient temperature of the steer-by-wire system is located; Determine the ambient compensation temperature of the measured temperature of each functional module according to the ambient temperature of the vehicle; Determine the position compensation temperature of each functional module's measured temperature based on the installation position of the temperature sensor that collects the measured temperature of each functional module; The measured temperature, environmental compensation temperature and position compensation temperature of each functional module are added together to obtain the detection temperature of each functional module.

[0037] The embodiment of the present disclosure performs position compensation and environment compensation on the measured temperature of each functional module, so that the detected temperature of each functional module finally obtained can reflect the most real temperature state of each functional module.

[0038] Among them, the calculation formula of the ambient compensation temperature is:

[0039] in, is the ambient compensation temperature, The ambient temperature of the steer-by-wire system is obtained through the vehicle's external sensor; is the environmental compensation coefficient; The main reasons for environmental compensation include compensating for the increased contact thermal resistance caused by the contraction of metal components during cold starts at low temperatures; offsetting the decrease in cooling system efficiency, such as increased radiator inlet temperature, at high temperatures; and eliminating the lag effect of heat exchange between components such as gearboxes and the environment during transient temperature differences.

[0040] The calculation formula for position compensation temperature is:

[0041] in, is the temperature after calibration, is the vertical distance from the sensor to the heat source, which is determined by the installation position of the sensor. is the installation position error calibration coefficient.

[0042] Detection temperature The calculation formula is:

[0043] Where, It is the temperature actually measured by the sensor, that is, the measured temperature.

[0044] In some embodiments, the confidence level of the temperature sensor detected by each functional module is obtained; Calculate the ratio of the confidence of each temperature sensor to the total confidence of all temperature sensors, and use it as the weight of the temperature detected by each functional module collected by each temperature sensor; The detection temperature of all functional modules is weightedly fused using the weight of the detection temperature of each functional module to obtain the detection layer temperature of the wire-controlled steering system.

[0045] The confidence level of each functional module detecting the temperature sensor is calculated based on the historical error standard deviation of each temperature sensor. Specifically:

[0046] Where, For sensors i The historical standard deviation of the error, It is a sensor i confidence level.

[0047] The calculation formula for the temperature of the detection layer of the wire steering system is:

[0048] Where, To detect the layer temperature of the steer-by-wire system, It is a functional module i Detection temperature.

[0049] The temperature of the detection layer of the wire steering system fully considers the detection temperature of each functional module, ensuring the accuracy of the temperature of the detection layer of the wire steering system.

[0050] In some embodiments, the copper loss heat generation of the motor winding is calculated and determined based on the current of the motor; According to the motor's rotation speed, calculate and determine the frictional heat generated by the motor's rotation; Calculate the sum of the heat generated by the copper loss of the motor winding and the frictional heat generated by the motor rotation to obtain the comprehensive heat generated by the motor; The comprehensive heat output and the gearbox conduction heat are weightedly fused and then added to the initial temperature reference and coupling compensation heat of the steer-by-wire system to obtain the predicted layer temperature of the steer-by-wire system.

[0051] Among them, the calculation formula of the predicted layer temperature of the wire steering system is:

[0052] Where, is the initial temperature reference for the steer-by-wire system; is the comprehensive thermal effect coefficient, which is the weight coefficient of the comprehensive heating amount; is the friction loss coefficient; It is the thermal effect term of the current, reflecting the heating of the winding copper loss; is the speed friction term, reflecting that the bearing friction loss is proportional to the cube of the speed (turbulent lubrication state); is the coupling compensation term, is the thermal coupling coefficient, i.e. the weight coefficient of heat conducted by the gearbox; The gearbox conducts heat. is the predicted layer temperature of the steer-by-wire system.

[0053] By comprehensively considering the motor current, speed and gearbox heat conduction, the predicted temperature of the steer-by-wire system is accurately determined.

[0054] In some embodiments, the detection layer temperature and the predicted layer temperature of the steer-by-wire system are fused to obtain a fused temperature of the steer-by-wire system.

[0055] The calculation formula for the fusion temperature is:

[0056] in, It is the fusion temperature of the steer-by-wire system, which serves as the input for the subsequent four-level gradient protection; is the fusion weight of the detection layer temperature of the steer-by-wire system.

[0057] The fusion temperature of the steer-by-wire system obtained by this method comprehensively considers the temperatures of each functional module and the temperature of the motor, and can accurately reflect the overall temperature state of the steer-by-wire system; and then, the output torque of the steer-by-wire system can be controlled according to the fusion temperature.

[0058] In some embodiments, calculating an error between a predicted layer temperature and a detected layer temperature of a steer-by-wire system; When the error is greater than the set error threshold, the weight coefficient used in the weighted fusion of the comprehensive heat output and the gearbox conduction heat is updated so that the error between the predicted layer temperature and the detection layer temperature of the wire control steering system obtained using the updated weight coefficient is less than or equal to the set error threshold.

[0059] That is, when | |> , trigger coefficient Online update to maintain prediction accuracy, is the set error threshold.

[0060] Preferably, = 5℃.

[0061] Among them, the comprehensive thermal effect coefficient The update strategy is as follows:

[0062] Constraints: ∈ [0.8 ] Where, is the updated comprehensive thermal effect coefficient, is the comprehensive thermal effect coefficient before updating, It is the benchmark value of comprehensive thermal effect coefficient.

[0063] It is a key parameter in the calculation formula of the predicted layer temperature of the wire control steering system, namely the comprehensive thermal effect coefficient, which characterizes the conversion efficiency of current, friction, etc. with temperature rise. Its influencing factors mainly include the aging of the motor winding material, the performance degradation of the cooling system, the change of contact thermal resistance, etc. Timely updates ensure the accuracy of temperature calculation of the prediction layer of the steer-by-wire system, thereby ensuring the accuracy of determination of the fusion temperature of the steer-by-wire system, and ultimately ensuring the effect of temperature protection of the steer-by-wire system.

[0064] In some embodiments, when the detected temperatures of each functional module cannot be obtained, the disclosed embodiments directly calculate the predicted temperature of the steer-by-wire system layer and use the predicted temperature as the final fusion temperature of the steer-by-wire system to control the output torque of the steer-by-wire system, thereby ensuring timely control of the steer-by-wire system.

[0065] In some embodiments, the specific process of controlling the output torque of the steer-by-wire system according to the fusion temperature of the steer-by-wire system includes: When the fusion temperature is less than or equal to a set first temperature threshold, the steer-by-wire system is controlled to output full power; When the fusion temperature is greater than a set first temperature threshold and less than or equal to a second temperature threshold, calculating a deviation between the fusion temperature and the first temperature threshold, and determining an output torque of the steer-by-wire system based on the deviation and a set first torque reduction amplitude; When the fusion temperature is greater than a set second temperature threshold and less than or equal to a third temperature threshold, calculating a deviation between the fusion temperature and the second temperature threshold, and determining an output torque of the steer-by-wire system based on the deviation and a set second torque reduction amplitude; When the fusion temperature is greater than a set third temperature threshold, the output torque of the steer-by-wire system is determined to be 0.

[0066] The first temperature threshold, the second temperature threshold, the third temperature threshold, the first torque reduction range, and the second torque reduction range are all determined according to the calibration of the vehicle's steer-by-wire system.

[0067] The first temperature threshold is 75°C; the second temperature threshold is 90°C; and the third temperature threshold is 105°C.

[0068] The first torque decreases by 2% / °C; the second torque decreases by (14 / 3)% / °C.

[0069] The torque limit curve proposed in the embodiment of the present disclosure is as follows: Figure 3 As shown, Figure 3 The horizontal axis is the fusion temperature of the steer-by-wire system; the vertical axis is the ratio of the output torque of the steer-by-wire system to the full-power output torque; the torque limit curve is obtained by pre-calibrating the steer-by-wire system, specifically, by fitting the fusion temperature of each steer-by-wire system and the maximum output torque of the steer-by-wire system corresponding to each fusion temperature; wherein the maximum output torque of the steer-by-wire system corresponding to each fusion temperature refers to the maximum output torque that ensures the normal operation of the steer-by-wire system when the temperature of the steer-by-wire system is the fusion temperature.

[0070] The torque limit curve is divided into four stages: full power mode stage, dynamic derating mode stage, safety mode stage and emergency mode stage.

[0071] When the fusion temperature is less than or equal to the set first temperature threshold, the steer-by-wire system is in full power mode, outputting full power and providing 100% assist torque, ensuring normal function and comfortable operation for the user. When the fusion temperature is greater than a set first temperature threshold and less than or equal to a second temperature threshold, the steer-by-wire system enters a dynamic derating mode. The deviation between the fusion temperature and the first temperature threshold is calculated, and the product of the deviation and the first torque reduction amplitude is subtracted from the output torque in full power mode to obtain the output torque of the steer-by-wire system, thereby smoothly reducing the output torque. When the fusion temperature is greater than the set second temperature threshold and less than or equal to the third temperature threshold, the steer-by-wire system enters the safety mode phase. The deviation between the fusion temperature and the second temperature threshold is calculated, and the output torque of the steer-by-wire system when the fusion temperature is at the second temperature threshold is multiplied by the product of the deviation and the second torque reduction amplitude to obtain the output torque of the steer-by-wire system. In this phase, in addition to limiting the output torque of the steer-by-wire system, the steer-by-wire system is also cooled by air to prevent the temperature from continuing to rise and enter emergency mode. When the fusion temperature exceeds the third temperature threshold, the steer-by-wire system enters emergency mode. During this stage, the steer-by-wire system's output torque is reduced to zero, the entire system is powered down, and the vehicle relies on the mechanical steering system for steering, ensuring basic steering functionality. The four-level gradient protection ensures smoother thermal torque limiting for steer-by-wire, preventing interruption of fixed-threshold control in extreme situations.

[0072] The temperature protection method for a steer-by-wire system based on multimodal sensing disclosed in an embodiment of the present disclosure comprehensively considers the temperature of each functional module and the temperature of the motor when calculating the fusion temperature of the steer-by-wire system, so that the fusion temperature of the steer-by-wire system can accurately reflect the overall temperature state of the steer-by-wire system; and then the output torque of the steer-by-wire system can be controlled according to the fusion temperature; and when the output torque of the steer-by-wire system is controlled according to the fusion temperature, the steer-by-wire system is gradient controlled through a four-level gradient protection mechanism, so that the control of the steer-by-wire system is smoother, and the function interruption of the fixed threshold control in extreme situations is avoided, so that the temperature protection is more precise and timely, and the real-time and safety requirements of the steer-by-wire system are met.

[0073] The disclosed embodiments further provide a temperature protection system for a steer-by-wire system based on multimodal sensing, including: A data acquisition unit, used to obtain the detected temperature of each functional module in the steer-by-wire system and the current and speed of the motor; The detection layer temperature calculation unit is used to perform weighted fusion of the detection temperatures of all functional modules to obtain the detection layer temperature of the steer-by-wire system; A prediction layer temperature calculation unit, configured to calculate and determine the prediction layer temperature of the steer-by-wire system based on the current and speed of the motor; a fusion temperature calculation unit, configured to fuse the detection layer temperature and the prediction layer temperature of the steer-by-wire system to obtain a fusion temperature of the steer-by-wire system; The output torque determination unit is used to limit the output torque of the steer-by-wire system when the fusion temperature is greater than a set first temperature threshold.

[0074] It should be noted that the multimodal sensing-based steer-by-wire system temperature protection system provided in the above-mentioned embodiment is merely an example of the division of the aforementioned functional modules when performing temperature protection control for a steer-by-wire system. In actual applications, the aforementioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. Furthermore, the multimodal sensing-based steer-by-wire system temperature protection system provided in the above-mentioned embodiment and the multimodal sensing-based steer-by-wire system temperature protection method embodiment are based on the same concept. The specific implementation process is detailed in the method embodiment and will not be repeated here.

[0075] The present disclosure also provides a computer device, which includes: a processor adapted to execute a computer program; A computer-readable storage medium having a computer program stored therein, wherein the computer program, when executed by the processor, implements the temperature protection method for a wire-controlled steering system based on multimodal sensing proposed in an embodiment of the present disclosure.

[0076] The embodiment of the present disclosure also proposes a computer-readable storage medium, which stores a computer program. The computer program is suitable for being loaded by a processor and executing the temperature protection method of the wire-controlled steering system based on multimodal sensing proposed in the embodiment of the present disclosure.

[0077] The embodiments of the present disclosure further provide a computer program product, which includes a computer program. When the computer program is executed by a processor, it implements the temperature protection method for the wire-controlled steering system based on multimodal sensing proposed in the embodiments of the present disclosure.

[0078] The methods proposed in the embodiments of the present disclosure can be directly implemented as execution by a hardware processor, or can be implemented using a combination of hardware and software modules in the processor. The software module can be located in a storage medium that is well-known in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, etc. The storage medium is located in the memory, and the processor reads the information in the memory and, in conjunction with its hardware, completes the steps of the above method. To avoid repetition, it will not be described in detail here.

[0079] Those skilled in the art will appreciate that the units and algorithm steps of the various examples described in conjunction with this embodiment can be implemented in electronic hardware or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0080] Although the above describes the specific embodiments of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without any creative work are still within the scope of protection of the present invention.

Claims

1. A temperature protection method for a steer-by-wire system based on multimodal sensing, characterized in that: include: Obtain the detected temperature of each functional module in the steer-by-wire system and the current and speed of the motor; Perform weighted fusion on the detection temperatures of all functional modules to obtain the detection layer temperature of the steer-by-wire system; Calculate and determine the predicted layer temperature of the steer-by-wire system based on the current and speed of the motor; The detection layer temperature and the prediction layer temperature of the steer-by-wire system are fused to obtain the fused temperature of the steer-by-wire system; When the fusion temperature is greater than a set first temperature threshold, the output torque of the steer-by-wire system is limited.

2. The temperature protection method for a steer-by-wire system based on multimodal sensing according to claim 1, wherein: Obtain the measured temperature of each functional module in the steer-by-wire system, the installation location of the measured temperature sensor of each functional module, and the ambient temperature of the steer-by-wire system; Determine the ambient compensation temperature of the measured temperature of each functional module according to the ambient temperature of the vehicle; Determine the position compensation temperature of each functional module's measured temperature based on the installation position of the temperature sensor that collects the measured temperature of each functional module; The measured temperature, environmental compensation temperature and position compensation temperature of each functional module are added together to obtain the detection temperature of each functional module.

3. The temperature protection method for a steer-by-wire system based on multimodal sensing according to claim 1, wherein: Obtain the confidence level of the temperature sensor detected by each functional module; Calculate the ratio of the confidence of each temperature sensor to the total confidence of all temperature sensors, and use it as the weight of the temperature detected by each functional module collected by each temperature sensor; The detection temperature of all functional modules is weightedly fused using the weight of the detection temperature of each functional module to obtain the detection layer temperature of the wire-controlled steering system.

4. The temperature protection method for a steer-by-wire system based on multimodal sensing according to claim 1, wherein: Calculate and determine the copper loss and heat generation of the motor winding based on the motor current; According to the motor's rotation speed, calculate and determine the frictional heat generated by the motor's rotation; Calculate the sum of the heat generated by the copper loss of the motor winding and the frictional heat generated by the motor rotation to obtain the comprehensive heat generated by the motor; The comprehensive heat generation and the gearbox conduction heat are weighted and fused, and then added to the initial temperature reference of the steer-by-wire system to obtain the predicted layer temperature of the steer-by-wire system.

5. The temperature protection method for a steer-by-wire system based on multimodal sensing according to claim 4, characterized in that: Calculate the error between the predicted layer temperature and the detected layer temperature of the steer-by-wire system; When the error is greater than the set error threshold, the weight coefficient used in the weighted fusion of the comprehensive heat output and the gearbox conduction heat is updated so that the error between the predicted layer temperature and the detection layer temperature of the wire control steering system obtained using the updated weight coefficient is less than or equal to the set error threshold.

6. The temperature protection method for a steer-by-wire system based on multimodal sensing according to claim 1, wherein: When the fusion temperature is less than or equal to a set first temperature threshold, the steer-by-wire system is controlled to output full power; When the fusion temperature is greater than a set first temperature threshold and less than or equal to a second temperature threshold, calculating a deviation between the fusion temperature and the first temperature threshold, and determining an output torque of the steer-by-wire system based on the deviation and a set first torque reduction amplitude; When the fusion temperature is greater than a set second temperature threshold and less than or equal to a third temperature threshold, calculating a deviation between the fusion temperature and the second temperature threshold, and determining an output torque of the steer-by-wire system based on the deviation and a set second torque reduction amplitude; When the fusion temperature is greater than a set third temperature threshold, the output torque of the steer-by-wire system is determined to be 0.

7. A temperature protection system for a steer-by-wire system based on multimodal sensing, characterized in that: include: A data acquisition unit, used to obtain the detected temperature of each functional module in the steer-by-wire system and the current and speed of the motor; The detection layer temperature calculation unit is used to perform weighted fusion of the detection temperatures of all functional modules to obtain the detection layer temperature of the steer-by-wire system; A prediction layer temperature calculation unit, configured to calculate and determine the prediction layer temperature of the steer-by-wire system based on the current and speed of the motor; a fusion temperature calculation unit, configured to fuse the detection layer temperature and the prediction layer temperature of the steer-by-wire system to obtain a fusion temperature of the steer-by-wire system; The output torque determination unit is used to limit the output torque of the steer-by-wire system when the fusion temperature is greater than a set first temperature threshold.

8. An electronic device, characterized in that: The device comprises: a processor adapted to execute a computer program; A computer-readable storage medium having a computer program stored therein, wherein the computer program, when executed by the processor, implements the temperature protection method for a steer-by-wire system based on multimodal sensing according to any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and the computer program is suitable for being loaded by a processor and executing the temperature protection method for a steer-by-wire system based on multimodal sensing according to any one of claims 1 to 6.

10. A computer program product, characterized in that The computer program product includes a computer program, and when the computer program is executed by a processor, the temperature protection method for a steer-by-wire system based on multimodal sensing according to any one of claims 1 to 6 is implemented.

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