Power-on centering control method for steer-by-wire vehicle, vehicle, storage medium and program product

Abstract

The invention discloses a steering-by-wire vehicle power-on centering control method, a vehicle, a storage medium and a program product. The method comprises the steps that the power-on frequency of the vehicle is obtained; generating an end learning request signal based on the power-on times; triggering an alignment learning state in response to an end learning request signal; in response to the alignment learning state, a neutral position calibration of the vehicle steering component is made based on the steering limit position. According to the method, the conventional power-on behavior of the vehicle is used as a trigger point, automatic learning and meso-position calibration of the tail end position (limit position) of the steering system are achieved, a traditional manual correction mode can be omitted, the defects that manual correction is poor in precision and low in overall efficiency are directly and efficiently overcome, and the accuracy of the steering system is improved. And meanwhile, the extra advantages of intelligent maintenance, operation and maintenance threshold reduction and the like are brought, the use convenience, reliability and safety of the steer-by-wire vehicle are remarkably improved, and the method can be widely applied to the technical field of vehicle control.

Description

Technical Field

[0001] The present invention relates to the field of vehicle control technology, and in particular to a power-on centering control method for a steer-by-wire vehicle, a vehicle, a storage medium, and a program product. Background Art

[0002] After long-term use, steer-by-wire vehicles can experience inaccurate steering centering due to mechanical wear and tear of chassis components, leading to vehicle deviation. Traditional vehicles rely on manual repairs to correct this deviation, sometimes requiring the vehicle to be returned to the factory for adjustments by specialized equipment and technicians. Manual repairs can result in poor centering accuracy, and existing centering correction methods are inefficient. Summary of the Invention

[0003] The main purpose of the embodiments of the present invention is to propose a power-on centering control method, vehicle, storage medium and program product for a wire-controlled steering vehicle, in order to solve at least one problem of the prior art. The present invention can accurately and efficiently realize the center correction of vehicle steering.

[0004] To achieve the above objectives, one aspect of an embodiment of the present invention provides a method for controlling power-on centering of a steer-by-wire vehicle, which is applied to a vehicle having a steer-by-wire system. The control method includes: Get the number of times the vehicle is powered on; Generate a terminal learning request signal based on the number of power-on times; In response to the terminal learning request signal, triggering the alignment learning state; In response to the alignment learning state, a neutral position calibration of the vehicle steering component is performed based on the steering limit positions.

[0005] In some embodiments, obtaining the number of times the vehicle is powered on includes: Recording the number of power-on times in response to an IG signal from a vehicle ignition switch via a power-on times recording module; When the power-on times recording module receives an IG signal, it increments the power-on times.

[0006] In some embodiments, the number of power-on times is recorded by a power-on times recording module, and generating a terminal learning request signal based on the number of power-on times includes: When the number of power-on times meets the preset number conditions, the terminal learning request signal is generated through the power-on times recording module; Send the terminal learning request signal to the state machine module.

[0007] In some embodiments, the control method further includes: When the power-on times meet the preset times condition, the power-on times recorded by the power-on times recording module is cleared.

[0008] In some embodiments, a steer-by-wire system includes a road feel simulator and a steer-by-wire actuator, and triggers an alignment learning state in response to an end-point learning request signal, including: In response to the terminal learning request signal, trigger the operation in the state of the road feeling simulator; In response to the state issuing operation, obtaining the real-time state of the road feeling simulator from the state machine module of the road feeling simulator; In response to the real-time status, the state machine module of the control-by-wire actuator executes a state follow jump; When the wire-controlled actuator completes the state following adjustment, it sends an identification signal of the correct learning state to the terminal learning module.

[0009] In some embodiments, a steer-by-wire system includes a road feel simulator and a steer-by-wire actuator, and in response to an alignment learning state, performs a center position calibration of a vehicle steering component based on a steering limit position, including: In response to an identification signal of a positive learning state, the terminal learning module triggers a road feel simulator and a controller of a wire-controlled actuator to control the actuator motor to perform an extreme steering operation; The terminal learning module determines the steering center position based on the recorded results of the extreme steering operation, and then sends the terminal learning completion flag to the center position calibration module; The center calibration module responds to the terminal learning completion flag, triggering the road feel simulator and the controller of the wire-controlled actuator to control the execution motor to perform the center calibration of the vehicle steering component based on the steering center position.

[0010] In some embodiments, determining the steering neutral position based on the recorded results of the extreme steering operation includes: Based on the extreme positions at both ends of the recorded results and in combination with the parameter information of the vehicle steering components, the steering center position is determined; The parameter information includes at least one of size information, running trajectory information and coordinate information.

[0011] To achieve the above-mentioned purpose, another aspect of an embodiment of the present invention proposes a vehicle, which includes a memory, a processor, and a program stored in the memory and runnable on the processor. When the program is executed by the processor, the above-mentioned power-on centering control method for a wire-controlled steer vehicle is implemented.

[0012] To achieve the above-mentioned purpose, another aspect of an embodiment of the present invention provides a computer-readable storage medium, which stores computer-executable instructions. When the computer-executable instructions are executed by a processor, the above-mentioned power-on centering control method for a wire-controlled steer vehicle is implemented.

[0013] To achieve the above-mentioned purpose, another aspect of an embodiment of the present invention provides a computer program product, including a computer program, which implements the above-mentioned power-on centering control method for a steer-by-wire vehicle when executed by a processor.

[0014] The embodiment of the present invention obtains the number of times the vehicle is powered on; generates a terminal learning request signal based on the number of power-on times; triggers an alignment learning state in response to the terminal learning request signal; and calibrates the center position of the vehicle's steering components based on the steering limit positions in response to the alignment learning state. The present invention utilizes the vehicle's regular power-on behavior as a trigger point to achieve automatic learning and center position calibration of the steering system's end positions (limit positions). The embodiment of the present invention can get rid of traditional manual calibration methods, directly and efficiently solving the shortcomings of poor manual calibration accuracy and overall low efficiency. At the same time, it brings additional advantages such as intelligent maintenance and reduced operation and maintenance thresholds, significantly improving the ease of use, reliability, and safety of steer-by-wire vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of an implementation environment for power-on centering control of a steer-by-wire vehicle provided by an embodiment of the present invention; Figure 2 This is a flow chart of a method for controlling power-on centering of a steer-by-wire vehicle provided by an embodiment of the present invention; Figure 3 A schematic diagram of the expanded process of step S100 provided in an embodiment of the present invention; Figure 4 A schematic diagram of the expanded process of step S200 provided in an embodiment of the present invention; Figure 5 A schematic diagram of an expanded flow chart of a power-on centering control method for a steer-by-wire vehicle provided in an embodiment of the present invention; Figure 6 A schematic diagram of the expanded process of step S300 provided in an embodiment of the present invention; Figure 7 A schematic diagram of the expanded process of step S400 provided in an embodiment of the present invention; Figure 8 A schematic diagram of an extended process of step S400 provided in an embodiment of the present invention; Figure 9 A schematic diagram of an application architecture of a power-on centering control method for a steer-by-wire vehicle provided by an embodiment of the present invention; Figure 10 A schematic diagram of the principle architecture of a power-on centering control method for a steer-by-wire vehicle provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0017] It should be noted that although the system diagrams illustrate functional module divisions and the flowcharts illustrate a logical sequence, in certain circumstances, the steps shown or described may be performed in a sequence that differs from the module divisions in the system or the sequence in the flowcharts. The terms "first / S100," "second / S200," and the like in the specification, claims, and drawings are used to distinguish similar objects and are not necessarily intended to describe a specific sequence or precedence.

[0018] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute a separate or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0019] It is understandable that the power-on centering control method for a steer-by-wire vehicle provided in an embodiment of the present invention can be applied to any computer device with data processing and computing capabilities (such as an on-board terminal device), and this computer device can be various types of terminals or servers. When the computer device in the embodiment is a server, the server is an independent physical server, or a server cluster or distributed system composed of multiple physical servers, or a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, domain name services, security services, CDN (Content Delivery Network), and big data and artificial intelligence platforms. In some embodiments, the terminal is a smart phone, tablet computer, laptop computer, desktop computer, etc., but is not limited to this.

[0020] like Figure 1 FIG. 1 is a schematic diagram of an implementation environment provided by an embodiment of the invention. Figure 1 , the implementation environment includes at least one terminal 102 and a server 101. The terminal 102 and the server 101 can be connected to the network in a wireless or wired manner to complete data transmission and exchange.

[0021] Server 101 can be an independent physical server, or a server cluster or distributed system composed of multiple physical servers. It can also be a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, domain name services, security services, CDN (Content Delivery Network), as well as big data and artificial intelligence platforms.

[0022] In addition, server 101 can also be a node server in a blockchain network. Blockchain is a new application model of computer technologies such as distributed data storage, peer-to-peer transmission, consensus mechanism, and encryption algorithm.

[0023] Terminal 102 may be a smartphone, tablet computer, laptop computer, desktop computer, smart speaker, smartwatch, etc. Terminal 102 may also be a vehicle-mounted terminal of the various device types described above, but is not limited thereto. Terminal 102 and server 101 may be connected directly or indirectly via wired or wireless communication, which is not limited in this embodiment of the present invention.

[0024] Based on the example Figure 1 In the implementation environment shown, an embodiment of the present invention provides a power-on centering control method for a steer-by-wire vehicle. The following is explained using the example of the power-on centering control method for a steer-by-wire vehicle applied in a server 101. It can be understood that the power-on centering control method for a steer-by-wire vehicle can also be applied in a terminal 102.

[0025] Reference Figure 2 , Figure 2 This is a flowchart of a method for controlling the centering of a steer-by-wire vehicle on a server provided by an embodiment of the present invention. The execution subject of the method for controlling the centering of a steer-by-wire vehicle on a server can be any of the aforementioned computer devices (including a server or a terminal). Figure 2 The method is applied to a vehicle with a steer-by-wire system, wherein the steer-by-wire system includes a road feel simulator and a steer-by-wire actuator; the road feel simulator and the steer-by-wire actuator each include a power-on count recording module, a state machine module, an end-point learning module, a mid-position calibration module, and an actuator motor. The method may include the following steps: S100, obtaining the number of times the vehicle is powered on; It should be noted that, in some embodiments, Figure 3 As shown, step S100 may include the following steps: S110, recording the number of power-ons in response to the IG signal of the vehicle ignition switch through the power-on number recording module; S120, when the power-on number recording module receives an IG signal, the power-on number is incremented.

[0026] For example, in some specific embodiments, a power-on count recording module records the number of power-on times, recording each time an IG signal is received. Specifically, obtaining the vehicle's power-on count is accomplished by the vehicle's power-on count recording module. This module can be integrated into a body control module (BCM), steering control unit (SCU), or gateway module. The power-on count recording module can include a counter based on non-volatile memory (such as EEPROM or Flash).

[0027] The power-on count recording module continuously monitors the IG signal generated by the vehicle's ignition switch via a hardwired connection or the CAN bus. This IG signal is active high (e.g., 12V) when the ignition switch is in the ON or START position. The module incorporates signal detection and debounce logic: a valid vehicle power-on event (i.e., an IG signal) is considered to have occurred only after the IG signal transitions from inactive (low) to active (high) and remains stable for a preset time (e.g., 100ms).

[0028] In response to detecting a valid power-on event, the power-on count recording module performs an increment operation: the currently stored power-on count value N is read from the non-volatile memory. N is increased by 1 to obtain a new value N+1. N+1 is written to the non-volatile memory for persistent storage. This increment operation is completed within a short time (such as within 10ms) after the valid power-on event is detected. Each independent and valid IG OFF to ON transition event triggers only one and only one increment operation. During a single power-on operation of the vehicle (the ignition switch remains ON), even if a state switch occurs within the system, the count value will not increase again as long as there is no new OFF to ON transition. The design capacity of the counter (such as 32 bits) is sufficient to cover the entire life cycle of the vehicle and includes overflow processing logic (such as resetting or reporting an error after reaching the maximum value). After the increment operation is completed, the latest power-on count value N+1 is used for subsequent determination to generate the terminal learning request signal.

[0029] S200, generating a terminal learning request signal based on the number of power-on times; It should be noted that the number of power-on times is recorded by the power-on times recording module. In some embodiments, such as Figure 4 As shown, step S200 may include the following steps: S210, when the number of power-on times meets the preset number condition, a terminal learning request signal is generated by the power-on number recording module; S220, the terminal learning request signal is sent to the state machine module.

[0030] For example, in some specific implementations, when the number of power-on cycles meets a preset number condition (e.g., 80 times, which can be set based on actual application requirements), a terminal learning request signal is sent to the state machine module. Specifically, the terminal learning request signal is generated based on the number of power-on cycles. The power-on number recording module (e.g., located in the BCM or SCU) performs the following steps: Threshold storage and judgment preparation: The non-volatile memory (NVM) configured in the pass count recording module pre-stores the terminal learning trigger threshold K (for example, K = 80, this value can be calibrated). Each time the vehicle is powered on and the power-on count N is incremented and updated, the module immediately performs a threshold judgment.

[0031] Threshold comparison: The comparison logic unit in the module compares the current power-on count N with the threshold K. The judgment condition is: N=K or N / K=0, and the condition is met.

[0032] Signal Generation: Once the conditions N = K or N / K = 0 are met, the Power-On Count Recording Module immediately generates a valid End-Learn Request signal. This signal is represented internally by a set software flag (e.g., Boolean variable EndLearnReq = true) and / or a high-level logic signal.

[0033] Signal transmission: The generated terminal learning request signal is sent to the state machine module responsible for managing the steering system working mode; If the power-on times recording module and the state machine are both in the SCU: the EndLearnReq flag is directly transmitted through the software interface (such as global variables, message passing) inside the SCU.

[0034] If the power-on count recording module is located in another controller (such as a BCM), the module constructs a specific CAN message (for example, message ID 0x1A0, with Bit 0 of Data Byte 0 set to 1 to indicate a valid request) and sends it via the CAN bus. The SCU receives and parses the message, extracting the value of Bit 0 as the input signal for its state machine module.

[0035] When the state machine module detects a valid terminal learning request signal, it triggers a state transition and enters the alignment learning state, thereby starting the subsequent mid-position calibration process based on the steering limit position.

[0036] Among them, in some embodiments, such as Figure 5 As shown, the method may further include the following steps: when the number of power-on times meets a preset number condition, clearing the number of power-on times recorded by the power-on times recording module.

[0037] For example, in some specific implementations, by resetting the power-on count to zero, it is possible to conveniently detect and determine the power-on count based on a preset count threshold to generate a terminal learning request signal. In some optional implementations, the power-on count may not be reset to zero. Correspondingly, the preset count threshold may be set to a predetermined value and all multiples thereof. Alternatively, when detecting and determining the power-on count, the power-on count may be divided by the predetermined value. If the value is divisible, the terminal learning request signal is generated by the power-on count recording module.

[0038] S300, in response to the terminal learning request signal, triggering the alignment learning state; It should be noted that the steer-by-wire system includes a road feel simulator and a steer-by-wire actuator. In some embodiments, such as Figure 6 As shown, step S300 may include the following steps: S310, in response to the terminal learning request signal, triggering the state sending operation of the road sense simulator; S320, in response to the state sending operation, obtaining the real-time state of the road sense simulator from the state machine module of the road sense simulator; S330, in response to the real-time state, controlling the state machine module of the wire-controlled actuator to execute the state following jump; S340, when the wire-controlled actuator completes the state following adjustment, sending an identification signal of the positive learning state to the terminal learning module.

[0039] For example, in some specific implementations, upon receiving a terminal learning request signal from the power-on count recording module, the state machine module transitions to the alignment learning state. The road feel simulator transmits the current state downward, and the drive-by-wire actuator state machine module follows the transition and provides feedback upward. Specifically, in response to the terminal learning request signal, the alignment learning state is triggered. Specifically, the steering system state machine module (located within the SCU) coordinates the road feel simulator (RFS) and the drive-by-wire actuator (SBW Actuator) to execute the following collaborative process: Triggering an RFS state transition: After the state machine module confirms a valid endpoint learning request signal, it proactively issues a state transition command to the state machine module of the road feel simulator (RFS). This command, sent via an internal SCU message (e.g., Set RFS State: Learn_Prep) or a CAN message (e.g., ID 0x1B0, Data [0x02]), instructs the RFS to enter a preset endpoint learning preparation state (e.g., Learning_Standby). In this state, the RFS ceases active road feel simulation and allows the steering wheel to rotate freely.

[0040] Confirm RFS status: The advanced state machine module continuously monitors the real-time status of RFS: By polling the RFS state machine module (internal reading of state variables or sending query messages).

[0041] Or wait for the RFS state machine module to actively report the status after successful switching (through internal messages or CAN messages, such as ID0x1B1, Data [0x05] indicates Learning_Standby).

[0042] The module waits and verifies that the current state of the RFS is the target state (Learning_Standby) issued.

[0043] Instructing the SBW Actuator to Follow State: Once the RFS is confirmed to be in the Learning_Standby state, the advanced state machine module immediately issues a command to the state machine module of the wire-controlled actuator (SBW Actuator), requesting it to execute a state-following transition. This command is sent via an internal SCU message (e.g., "Sync SBW State to RFS: Learn_Prep") or a CAN message (e.g., "ID0x1C0, Data [0x03, 0x05]"), instructing the SBW Actuator to synchronously transition to the actuator state corresponding to the RFS learning preparation state (e.g., "Endstop_Learning_Prep"). In this state, the actuator is ready to receive precise position control commands from the end-point learning module.

[0044] Sending a learning ready flag: After the state machine module of the wire-controlled actuator (SBW Actuator) successfully switches and stabilizes in the Endstop_Learning_Prep state, it generates and sends a positive learning state flag signal to the end learning module. This signal indicates that the actuator is ready and the learning process can be safely started: Inside the SCU, it is passed to the end-stop learning module by setting the software flag SBW_EndstopLearn_Ready = 1.

[0045] If the SBW Actuator is an independent ECU, it is sent to the terminal learning module in the SCU via a CAN message (such as ID 0x1C1, Data [Bit0=1]).

[0046] At this point, the alignment learning state has been effectively triggered: the terminal learning module receives the alignment learning state identification signal from the SBW actuator, indicating that the system (RFS is in a ready state allowing free steering wheel rotation, and the SBW actuator is in a ready state to receive learning control commands) is ready and can safely perform the subsequent "center position calibration of the vehicle steering components based on the steering limit positions" operation. S400, in response to the alignment learning state, performing a center position calibration of the vehicle steering component based on the steering limit position; It should be noted that the steer-by-wire system includes a road feel simulator and a steer-by-wire actuator. In some embodiments, such as Figure 7 As shown, step S400 may include the following steps: S410, in response to the identification signal of the positive learning state, the terminal learning module triggers the controller of the road feel simulator and the wire-controlled actuator to control the execution motor to perform an extreme steering operation; S420, in response to the terminal learning module, the steering center position is determined according to the recorded result of the extreme steering operation, and then the terminal learning completion flag is sent to the center position calibration module; S430, in response to the terminal learning completion flag, the center position calibration module triggers the controller of the road feel simulator and the wire-controlled actuator to control the execution motor to perform a center position calibration of the vehicle steering component based on the steering center position.

[0047] For example, in some specific implementations, after the terminal learning module receives the alignment learning status, the road feel simulator and the controller of the wire-controlled steering device respectively control their respective execution motors to make the steering wheel and rack reach their own left and right limit positions respectively. The terminal learning module records the left and right limit positions respectively, and obtains the up and down turn center position by calculation. The up and down turn execution motors control the steering wheel and rack to reach the center position after the up and down turn calculations respectively. The terminal learning module sends the terminal learning completion flag to the center position calibration module; further, after the center position calibration module receives the terminal learning completion flag sent by the terminal learning module, it performs the up and down turn center position calibration, and after the calibration is successful, it sends a center position calibration completion signal to the state machine module. Specifically, in response to the alignment learning status, the center position calibration of the vehicle steering component is performed based on the steering limit position, which can be specifically performed collaboratively by the terminal learning module and the center calibration module: Triggering limit position detection: After the end learning module receives a valid identification signal of the alignment learning state (such as SBW_Ready_For_Endstop_Learning = 1), it performs the following steps: Send a low-speed position control command (for example, speed < 10deg / s, gentle acceleration) to the SBW Actuator controller, instructing it to drive the steering actuator motor in a controlled manner: First move to the left steering limit position (target position = -Max_Allowed_Pos or continue driving until position stagnation is detected and the motor current reaches the preset safety limit or the mechanical limit switch is triggered).

[0048] Record the raw value Left_Endstop_Pos of the motor position sensor (such as resolver) when the left limit is reached.

[0049] Then move to the right steering limit position (target position = +Max_Allowed_Pos or the same as above) and record the position value Right_Endstop_Pos.

[0050] Sends commands to the RFS controller to maintain it in a low torque / free-wheeling state, ensuring the steering wheel can smoothly follow the rotation of the wheels.

[0051] The entire detection process is protected by speed, acceleration, current limit and timeout.

[0052] Calculate the steering center position: The terminal learning module is based on the recorded left and right extreme position values: Performs the core calculation: Steering_Center_Position = (Left_Endstop_Pos + Right_Endstop_Pos) / 2.

[0053] Optionally, a sanity check can be performed (e.g. whether the median is within the interval (Left_Endstop_Pos, Right_Endstop_Pos) and is approximately equidistant from the left and right limits).

[0054] Sending learning completion flag: After successfully calculating Steering_Center_Position: The end learning module sets the end learning completion flag (Endstop_Learning_Complete_Flag =TRUE).

[0055] This flag, together with the calculated Steering_Center_Position value, is sent to the center position calibration module through the SCU internal data bus or message queue.

[0056] Perform mid-point calibration: After the mid-point calibration module receives a valid end-point learning completion flag (for example, Endstop_Learning_Complete_Flag = TRUE): Send calibration instructions and Steering_Center_Position value to the SBW Actuator controller, instructing it to: The received Steering_Center_Position is written into its non-volatile memory (NVM, such as EEPROM).

[0057] This value is set as the permanent zero reference for motor position control. All subsequent wheel angle commands are relative to this zero point.

[0058] Send calibration commands to the RFS controller (usually with steering wheel angle values ​​calculated based on Steering_Center_Position or currently read): Command it to write the steering wheel angle sensor value representing the steering wheel centered straight driving state into its NVM.

[0059] Set this value as the permanent zero point of the steering wheel angle sensor (Angle Zero Point). All subsequent steering wheel angle measurements are relative to this zero point.

[0060] The RFS and SBW Actuator controllers send a confirmation signal after successful completion of calibration.

[0061] The final result: Through the above process, the vehicle's steering system accurately calculates and calibrates the mechanical center position (Steering_Center_Position) based on the physical steering extremes. The control systems of the road feel simulator (RFS) and the drive-by-wire actuator (SBWActuator) both perform zero-position calibration using this center position as a reference, ensuring strict correspondence between the steering wheel's center position and the actual straight-ahead position of the wheels, achieving precise "Mid-Position Calibration" of the vehicle's steering components. The system then exits the learning state and resumes normal driving mode.

[0062] Among them, in some embodiments, such as Figure 8 As shown, determining the steering center position based on the recorded results of the extreme steering operation can include the following steps: determining the steering center position based on the extreme positions at both ends in the recorded results and combined with the parameter information of the vehicle steering components; wherein the parameter information includes at least one of size information, running trajectory information and coordinate information.

[0063] For example, in some specific implementations, several specific implementation examples are provided below to illustrate how to combine different "parameter information" to determine the steering neutral position. These examples can be used alone or in combination.

[0064] 1. Example 1: Based on geometric size parameters (size information): Application of parameter information: Assume that the core component of the steering actuator is the rack-pinion. The key dimensional information includes: L_total: The total effective travel length of the steering rack (the total length from the physical left limit to the physical right limit).

[0065] D_pinion or P_screw: Pitch diameter of the steering pinion (for racks).

[0066] Determine the median process: The terminal learning module controls the execution motor to drive the steering component (such as the rack) to reach and record the left limit position (Pos_L) and the right limit position (Pos_R).

[0067] Calculate the total travel: Travel_Total = |Pos_R - Pos_L| (Unit: motor encoder counts or actual length units, such as mm). This value should theoretically be close to or equal to L_total, but the actual value may be slightly different due to installation, wear, or sensor errors.

[0068] Calculate the theoretical median position: Pos_Center_Theoretical = (Pos_R + Pos_L) / 2 (simple midpoint based on encoder counts).

[0069] Verify / correct based on dimensional information (key steps): Convert Pos_Center_Theoretical to the actual displacement of the rack D_center (for example, using the conversion relationship between encoder counts and lead / pitch: D_center = Pos_Center_Theoretical × (P_screw / Counts_Per_Rev) or D_center = Pos_Center_Theoretical × (π × D_pinion / Counts_Per_Rev)).

[0070] The theoretical length of the total stroke L_total is known.

[0071] The theoretical displacement from the midpoint to either end point should be calculated as L_total / 2.

[0072] Compare D_center with L_total / 2: If the two are consistent within the allowed tolerance range, then Pos_Center_Theoretical is confirmed to be the valid steering center position (Steering_Center).

[0073] If there is a significant deviation (out of tolerance), it may indicate installation error, component wear, or sensor failure. The system can: Use Pos_Center = Pos_L + (L_total / 2) / Conversion_Factor (trust the known hard size parameter L_total first).

[0074] Trigger fault diagnosis or calibration failure signal.

[0075] Compensation calculation is performed based on the deviation value (for example, Pos_Center_Adjusted = Pos_Center_Theoretical + Compensation_Value).

[0076] Beneficial Effect: Using the known hard dimension parameter (L_total) to verify and correct the midpoint calculated based on the sensor readings improves the accuracy and robustness of the midpoint calibration and reduces over-reliance on the absolute accuracy of the sensor.

[0077] 2. Example 2: Based on motion trajectory constraints (operation trajectory information): Application of parameter information: The vehicle steering system has inherent kinematic constraints. Key trajectory information includes: The geometric connection relationship between the tie rod, knuckle, and rack / actuator output (such as length and hinge point location).

[0078] The wheel's contact point trajectory characteristics during steering are caused by the kingpin inclination angle (Kingpin Inclination Angle) and caster angle (CasterAngle) of the wheel steering knuckle (Ackerman's principle is a more complex trajectory constraint, mainly referring to single-sided wheel kinematics here).

[0079] A mathematical model or lookup table of the kinematic relationship between the wheels and steering components.

[0080] Determine the median process: The terminal learning module controls the execution motor to drive the steering component to reach and record the left limit position (Pos_L) and the right limit position (Pos_R).

[0081] Calculate the initial midpoint: Pos_Mid = (Pos_L + Pos_R) / 2.

[0082] Correction based on motion trajectory information (key steps): The system knows that in mechanical neutral, the left and right wheels should be in a straight-ahead state (Toe Angle ≈ 0°).

[0083] Using the kinematic model of the steering system (based on the above-mentioned geometric connection relationship and angle parameters), the functional relationship between the actuator position (Pos) and the steering angle (δ) of the corresponding wheel can be calculated: δ = f(Pos).

[0084] Goal: Find an actuator position Pos_Center such that f(Pos_Center) ≈ 0° (for a bilaterally symmetric system, both the left and right wheels should be at 0°).

[0085] method: Between Pos_L and Pos_R, the model is used to calculate the theoretical wheel steering angle δ corresponding to different positions Pos.

[0086] Find the position Pos that makes δ closest to 0°. This position is the corrected steering center (Steering_Center).

[0087] Alternatively, because the model is usually monotonic, iterative calculation or interpolation can be performed near Pos_Mid to quickly find the Pos corresponding to δ=0°.

[0088] Another simplification approach (for symmetric systems): Due to kinematic constraints, the actuator travel required from the wheel's center position to the left extreme and from the center position to the right extreme may not be exactly equal (for example, the asymmetry in the "steering return torque" caused by the kingpin inclination angle is small, but strictly speaking, it exists). The system can record the motor angle / displacement (Travel_L, Travel_R) required to move from Pos_Mid to Pos_L and Pos_R, respectively. Theoretically, in a perfect center position, Travel_L should equal Travel_R. By fine-tuning Pos_Mid so that Travel_L equals Travel_R, a steering center position that better reflects kinematics can be found.

[0089] Beneficial Effect: By taking into account the actual kinematic characteristics of the steering system (such as the steering geometry caused by the kingpin angle), the calculated neutral position is more consistent with the actual straight-ahead position of the wheels, improving the vehicle's straight-ahead stability. This is particularly important for non-ideally symmetrical steering systems or when installation errors exist.

[0090] 3. Example 3: Based on the coordinate system and hard point coordinates (coordinate information): Application of parameter information: When designing a vehicle, the key hard points of the steering system have specific coordinate values ​​in the vehicle coordinate system. These coordinate information are important parameters. Key hard points include: Center points of the upper and lower kingpin ball joints of the left and right steering knuckles (P_Upper_L, P_Lower_L, P_Upper_R, P_Lower_R).

[0091] Connection point between the steering rack output / actuator output and the inner ball joints of the left and right tie rods (P_Inner_TieRod_L, P_Inner_TieRod_R).

[0092] Connection points of the left and right tie rod outer ball joints and the steering knuckle (P_Outer_TieRod_L, P_Outer_TieRod_R).

[0093] Determine the median process: The terminal learning module controls the actuator motor to drive the steering component to reach and record the left and right extreme positions (Pos_L and Pos_R). Pos_L / R corresponds to the position of the actuator output (such as rack displacement).

[0094] Calculate the initial midpoint: Pos_Mid = (Pos_L + Pos_R) / 2.

[0095] Combine coordinate information for accurate calculation (key step): The system stores the design coordinate values ​​(X, Y, Z) of the above key hard points in the vehicle coordinate system.

[0096] When the actuator is at a certain position Pos, the real-time coordinates of P_Inner_TieRod_L and P_Inner_TieRod_R in the vehicle coordinate system can be determined (because the actuator position Pos directly determines the position of the rack or output end, and thus determines the coordinates of the inner ball joint point).

[0097] The steering center position (Steering_Center) should satisfy the following conditions: the left and right wheels are in a straight-ahead state, that is, the projection of the left and right kingpin axes (defined by P_Upper_L / R and P_Lower_L / R) on the horizontal plane should be parallel to the vehicle's longitudinal axis, and the line connecting the left and right wheel centers should be perpendicular to the vehicle's longitudinal axis (ideal situation).

[0098] Using inverse kinematics: For a given actuator position Pos, the coordinates of P_Inner_TieRod_L and P_Inner_TieRod_R are calculated.

[0099] Based on the hard point coordinates (P_Outer_TieRod_L / R, P_Upper_L / R, P_Lower_L / R) and the current P_Inner_TieRod_L / R coordinates, the steering angles (δ_L, δ_R) of the left and right wheels and / or the position / attitude of the wheel center can be accurately calculated using spatial geometry (such as solving the spherical joint distance constraint).

[0100] Goal: Find an actuator position Pos_Center such that the calculated δ_L and δ_R are both equal to 0° (or meet the vehicle design straight-ahead state requirements, such as total toe Toe = 0°).

[0101] Due to computational complexity, a mapping relationship between Pos and (δ_L, δ_R) is typically established in advance (using a lookup table or fitting function). Once the travel range is determined using Pos_L and Pos_R, the Pos corresponding to δ_L = 0° and δ_R = 0° can be accurately calculated within this range. This position is the precise steering center based on the hard point coordinates.

[0102] Beneficial Effects: This is the most theoretically accurate method, calculating the center position directly based on the physical geometry of the steering system (hard-point coordinates). This minimizes the impact of manufacturing and installation errors (as long as the hard-point coordinates are accurately measured or calibrated) on the center position calibration, achieving the highest accuracy in vehicle straight-ahead positioning.

[0103] 4. Combined application examples: Size + Trajectory: First, use the size information (L_total) to quickly calculate and verify an initial median position (Pos_Mid), and then use a simplified motion trajectory model (such as the left and right travel symmetry check Travel_L == Travel_R?) to fine-tune the median position.

[0104] Coordinates + Dimensions: The precise center position (Pos_Center) calculated using hard point coordinates should ensure that the displacement differences from the center to the left and right extremes (|Pos_Center - Pos_L| and |Pos_R - Pos_Center|) are close, and their sum is close to L_total. This can be used as a validation condition for the reasonableness of the coordinate calculation results.

[0105] Trajectory + Coordinates: Use hard point coordinates to establish an accurate kinematic model (δ = f(Pos)), which serves as the core basis of "operation trajectory information" and is used to calculate the median position.

[0106] In summary, the application of this parameter information significantly improves the accuracy, reliability, and robustness of the power-on centering (center calibration) of steer-by-wire vehicles. It solves the problem of inaccurate centering caused by installation errors, wear, and sensor drift when relying solely on sensor readings. It is a key technical link in ensuring the basic performance and safety of steer-by-wire systems.

[0107] In order to explain the principle of the technical solution of the present invention in detail, the overall process of the present invention is described below in combination with some specific embodiments. It is easy to understand that the following is an explanation of the technical principle of the present invention and cannot be regarded as a limitation of the present invention.

[0108] First of all, it should be noted that after long-term use, steer-by-wire vehicles will suffer from inaccurate steering center position due to mechanical wear of vehicle chassis parts and other reasons, thus causing the vehicle to veer off course. In this case, vehicles using traditional steering systems will perform center position correction through center position self-learning. However, since the steer-by-wire system adds a road feel simulator compared to the traditional reversing system, the center position learning can only calibrate the steer-by-wire actuator, and the center position calibration of the steer-by-wire system requires both upward and downward turns to be performed simultaneously. Therefore, it cannot meet the needs of steer-by-wire center position calibration. A new logic that meets the needs of center position calibration of the steer-by-wire system is needed.

[0109] In view of this, if Figure 9 and Figure 10 As shown, the embodiment of the present invention proposes a technical solution for electrical centering of a steer-by-wire vehicle. The present invention can perform center calibration on the steer-by-wire system after the vehicle has been used for a period of time, thereby preventing the vehicle from running off the track. Specifically, the embodiment of the present invention can achieve the following: The steer-by-wire system includes a road feel simulator and a steer-by-wire actuator. The road feel simulator and the steer-by-wire actuator contain a power-on count recording module, a state machine module, an end-point learning module, a mid-position calibration module, and an actuator motor. The road feel simulator and the steer-by-wire actuator can transmit and verify the state machine and mid-position calibration status to each other.

[0110] The power-on times recording module records the power-on times of the road feel simulator and the wire-controlled actuator each time an IG signal is received. When the number reaches 80, the number is reset to zero and a terminal learning request signal is sent to the state machine module.

[0111] After receiving the terminal learning request signal sent by the power-on times recording module, the state machine module jumps to the alignment learning state. The road feel simulator sends the current state downward, and the wire-controlled actuator state machine module follows the jump and provides feedback upward. After receiving the mid-position calibration completion signal sent by the mid-position calibration module, the state machine module jumps to the normal working state. The up and down turns are mutually verified, and the wire-controlled steering system can work normally.

[0112] After the terminal learning module receives the alignment learning status, the road feel simulator and the controller of the wire-controlled steering gear respectively control their respective execution motors to make the steering wheel and rack reach their own left and right extreme positions respectively. The terminal learning module records the left and right extreme positions respectively, and obtains the up and down turn center position through calculation. The up and down turn execution motors control the steering wheel and rack to reach the center position after the up and down turn calculation respectively. The terminal learning module sends the terminal learning completion flag to the center position calibration module.

[0113] After receiving the terminal learning completion flag sent by the terminal learning module, the mid-position calibration module performs up and down mid-position calibration. After the calibration is successful, it sends a mid-position calibration completion signal to the state machine module.

[0114] In summary, the present invention, by determining that the vehicle has been powered on a predetermined number of times, automatically performs terminal learning via the steer-by-wire system's road feel simulator and actuator. The system then calculates the current vehicle steer-by-wire system neutral position based on the terminal and updates the neutral position. Specifically, the present invention utilizes an effective steer-by-wire vehicle power-on centering strategy to address the issue of vehicle deviation caused by mechanical issues with chassis components leading to inaccurate steering neutral position.

[0115] An embodiment of the present invention further provides a vehicle control device, comprising a memory, a processor, and a program stored in the memory and executable on the processor, wherein the program implements the control method of the above embodiment when executed by the processor.

[0116] For example, the processor and memory in a vehicle controller can be connected via a bus. Memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs and non-transitory computer executable programs. Furthermore, the memory can include high-speed random access memory and non-transitory memory, such as at least one disk drive, flash memory device, or other non-transitory solid-state memory device. In some embodiments, the memory can optionally include memory remotely located relative to the control processor, and these remote memories can be connected to the control device via a network.

[0117] The non-transient software program and instructions required to implement the control method of the above embodiment are stored in the memory, and when executed by the processor, the control method of the above embodiment is executed. Figure 2 Steps S100 to S400 of the method, Figure 3 Method steps S110 to S120, etc.

[0118] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, i.e., they may be located in one place or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of this embodiment.

[0119] An embodiment of the present invention further provides a vehicle, comprising the vehicle control device of the above embodiment.

[0120] The vehicle can be a private car, such as a sedan, SUV, MPV, or pickup truck. It can also be a commercial vehicle, such as a van, bus, small truck, or large trailer. The vehicle must have an electric motor that can output power or store mechanical energy as a generator. If the vehicle is a new energy vehicle, it can be a hybrid or a pure electric vehicle.

[0121] Since the vehicle applies all the technical solutions of the above-mentioned control device or vehicle controller, it has at least all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be repeated here.

[0122] In addition, an embodiment of the present invention further provides a computer-readable storage medium, which stores computer-executable instructions for executing the above-mentioned method for controlling the centering of a steer-by-wire vehicle. Figures 2 to 8 The method steps in .

[0123] It is worth noting that since the computer-readable storage medium of an embodiment of the present invention can execute the power-on centering control method for a steer-by-wire vehicle of any of the above-mentioned embodiments, the specific implementation methods and technical effects of the computer-readable storage medium of an embodiment of the present invention can refer to the specific implementation methods and technical effects of the power-on centering control method for a steer-by-wire vehicle of any of the above-mentioned embodiments.

[0124] In addition, an embodiment of the present invention further provides a computer program product, including a computer program or computer instructions, the computer program or computer instructions being stored in a computer-readable storage medium, the processor of a computer device reading the computer program or computer instructions from the computer-readable storage medium, and the processor executing the computer program or computer instructions, so that the computer device executes the above-described method for controlling the centering of a steer-by-wire vehicle. For example, the above-described method is executed. Figures 2 to 8 The method steps in .

[0125] It is worth noting that since the computer program product of the embodiment of the present invention can execute the power-on centering control method for steer-by-wire vehicles of any of the above-mentioned embodiments, the specific implementation methods and technical effects of the computer program product of the embodiment of the present invention can refer to the specific implementation methods and technical effects of the power-on centering control method for steer-by-wire vehicles of any of the above-mentioned embodiments.

[0126] Those skilled in the art will appreciate that all or some of the steps and systems disclosed above can be implemented as software, firmware, hardware, or any suitable combination thereof. Some or all of the physical components may be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software may be distributed on computer-readable media, which may include computer storage media (or non-transitory media) and communication media (or transient media). As is well known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information, such as computer-readable instructions, data structures, program modules, or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disks (DVDs) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and can be accessed by a computer. Furthermore, as is well known to those skilled in the art, communication media typically includes computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism, and may include any information delivery media.

[0127] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, i.e., they may be located in one place or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of this embodiment.

Claims

1. A method for controlling power-on centering of a steer-by-wire vehicle, characterized in that: Applied to a vehicle with a steer-by-wire system, the control method includes: Get the number of times the vehicle is powered on; generating a terminal learning request signal based on the power-on times; In response to the terminal learning request signal, triggering an alignment learning state; In response to the alignment learning state, a center position calibration of the vehicle steering component is performed based on the steering limit position.

2. The power-on centering control method for a steer-by-wire vehicle according to claim 1, characterized in that: The obtaining of the number of times the vehicle is powered on includes: recording the number of power-on times in response to an IG signal from an ignition switch of the vehicle by a power-on number recording module; When the power-on times recording module receives the IG signal once, it increments the power-on times.

3. The power-on centering control method for a steer-by-wire vehicle according to claim 1, characterized in that: The number of power-on times is recorded by a power-on times recording module, and the generating of the terminal learning request signal based on the number of power-on times includes: When the power-on times meet the preset times condition, the terminal learning request signal is generated by the power-on times recording module; The terminal learning request signal is sent to the state machine module.

4. The power-on centering control method for a steer-by-wire vehicle according to claim 2 or 3, characterized in that: The control method further includes: When the power-on times meet a preset times condition, the power-on times recorded by the power-on times recording module is cleared.

5. The power-on centering control method for a steer-by-wire vehicle according to claim 1, characterized in that: The steer-by-wire system includes a road feel simulator and a steer-by-wire actuator, and triggering an alignment learning state in response to the terminal learning request signal includes: In response to the terminal learning request signal, triggering the state of the road feeling simulator to start operation; In response to the state sending operation, obtaining the real-time state of the road feeling simulator from a state machine module of the road feeling simulator; In response to the real-time state, controlling the state machine module of the wire-controlled actuator to execute a state following jump; When the wire-controlled actuator completes the state following adjustment, it sends an identification signal of the alignment learning state to the terminal learning module.

6. The power-on centering control method for a steer-by-wire vehicle according to claim 1, characterized in that: The steer-by-wire system includes a road feel simulator and a steer-by-wire actuator. The steer-by-wire system performs a mid-position calibration of a vehicle steering component based on a steering limit position in response to the alignment learning state, including: In response to the identification signal of the alignment learning state, the terminal learning module triggers the road feeling simulator and the controller of the wire-controlled actuator to control the actuator motor to perform an extreme steering operation; Determining the steering center position according to the recorded result of the extreme steering operation by the terminal learning module, and then sending the terminal learning completion flag to the center position calibration module; The center position calibration module responds to the terminal learning completion flag, triggering the road feel simulator and the controller of the wire-controlled actuator to control the actuator motor to perform center position calibration of the vehicle steering component based on the steering center position.

7. The power-on centering control method for a steer-by-wire vehicle according to claim 6, characterized in that: Determining the steering neutral position according to the recorded result of the extreme steering operation includes: Determining the steering center position based on the extreme positions at both ends of the recorded result and in combination with parameter information of the vehicle steering component; The parameter information includes at least one of size information, running trajectory information and coordinate information.

8. A vehicle, characterized in that: The invention comprises a memory, a processor and a program stored in the memory and executable on the processor, wherein when the program is executed by the processor, the power-on centering control method for a steer-by-wire vehicle as claimed in any one of claims 1 to 7 is implemented.

9. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are used to enable a computer to execute the power-on centering control method for a steer-by-wire vehicle according to any one of claims 1 to 7.

10. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

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