Steering-by-wire test bench and load control method

Abstract

The invention provides a steer-by-wire test bench and a load control method. The stand comprises an upper computer, a real-time simulator, a data acquisition system, a steer-by-wire system and a load loading system. The upper computer is in communication connection with the real-time simulator, the real-time simulator is in communication connection with the data acquisition system, and the data acquisition system is respectively in communication connection with the steer-by-wire system and the load loading system; the load loading system comprises a loading sensing module, the loading sensing module comprises a loading device and a pull pressure sensor, the loading device comprises a load motor, a rocker arm, a connecting shaft and a load motor controller, one end of the rocker arm is fixed on the load motor, and the other end of the rocker arm is mechanically connected with the connecting shaft; the connecting shaft is further mechanically connected with one end of the steer-by-wire system through a pull pressure sensor. By using the rack of the invention, the response speed can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of steer-by-wire system testing, and in particular to a steer-by-wire test bench and a load control method. Background Art

[0002] The steer-by-wire system uses electronic and electrical signals to control vehicle steering, greatly improving the driving experience. However, due to the elimination of the mechanical connection between the steering wheel and the tire and the lack of a mechanical backup system, the reliability and safety of the steer-by-wire system become particularly critical. Before it is put into mass production, it must be fully and comprehensively tested on a bench.

[0003] On the one hand, in order to ensure the authenticity and reliability of the test results, the wire-controlled steering test bench needs to simulate the load resistance in the actual driving process as accurately as possible. At present, most load simulation devices use servo electric cylinders, which can realize load simulation under different working conditions. However, in the actual working process, due to the friction and wear between the servo motor and the cylinder sleeve, the rotational inertia of the system will increase, resulting in a slower response time of load control and difficulty in achieving high-precision control. On the other hand, in the steering test bench test, the presence of the network communication module will inevitably generate dynamic network delays, which will not only affect the load simulation performance, but in severe cases, it will even cause the system to become unstable, posing a higher challenge to the control of load simulation. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0005] To this end, a first object of the present invention is to provide a steer-by-wire test bench to improve the response speed.

[0006] A second objective of the present invention is to provide a load control method for a steer-by-wire test bench.

[0007] To achieve the above-mentioned object, the first aspect of the present invention provides a wire-controlled steering test bench, comprising a host computer, a real-time simulator, a data acquisition system, a wire-controlled steering system and a load loading system; the host computer is communicatively connected to the real-time simulator, the real-time simulator is communicatively connected to the data acquisition system, and the data acquisition system is communicatively connected to the wire-controlled steering system and the load loading system respectively;

[0008] The load loading system includes a loading sensing module, which includes a loading device and a tension pressure sensor. The loading device includes a load motor, a rocker arm, a connecting shaft and a load motor controller. One end of the rocker arm is fixed to the load motor, and the other end of the rocker arm is mechanically connected to the connecting shaft. The connecting shaft is also mechanically connected to one end of the wire-controlled steering system through the tension pressure sensor.

[0009] In the steer-by-wire test bench provided in the first aspect of the present invention, there are multiple load sensing modules, and different load sensing modules are connected to different ends of the steer-by-wire system.

[0010] To achieve the above-mentioned object, the second aspect of the present invention proposes a load control method of the steer-by-wire test bench provided by the first aspect of the present invention, comprising:

[0011] The host computer sends the driver's operating instructions to the real-time simulator;

[0012] The data acquisition system sends the actual load force collected by the tension and pressure sensors to the real-time simulator;

[0013] The real-time simulator obtains an expected load force based on the driver operation command, and obtains an expected matrix based on the expected load force, the nominal load force and the actual load force, thereby generating a first control command and a second control command;

[0014] The steer-by-wire system performs a steering action based on the first control instruction;

[0015] The loading device obtains the expected torque based on the second control instruction, and drives the load motor to operate based on the expected torque to dynamically load the steer-by-wire system.

[0016] In the load control method for a steer-by-wire test bench provided in the second aspect of the present invention, the expected matrix is ​​obtained based on the expected load force, the nominal load force and the actual load force, including: obtaining a corrected load force based on the nominal load force and the actual load force; and obtaining an expected torque based on the corrected load force and the expected load force.

[0017] In the load control method for a steer-by-wire test bench provided in the second aspect of the present invention, a nominal load loading system transfer function model is established in the frequency domain to obtain the nominal load force.

[0018] In the load control method for a steer-by-wire test bench provided in the second aspect of the present invention, the nominal load force satisfies:

[0019] F Rpi (s) = G i1 T mi (s)+G i2 D i (s)

[0020] In the formula, F Rpi (s) is the nominal load force corresponding to the i-th loading device, G i1 is the transfer function from the torque of the load motor corresponding to the i-th loading device to the corresponding load force, T mi(s) is the torque of the load motor corresponding to the i-th loading device, G i2 is the transfer function from the system disturbance corresponding to the i-th loading device to the corresponding load force, D i (s) is the system disturbance corresponding to the i-th loading device.

[0021] In the load control method for a steer-by-wire test bench provided in the second aspect of the present invention, obtaining a corrected load force based on the nominal load force and the actual load force includes: establishing a delay attenuator according to the actual load force and the nominal load force to obtain a corrected load force.

[0022] In the load control method for a steer-by-wire test bench provided in the second aspect of the present invention, the corrected load force satisfies:

[0023]

[0024] In the formula, F Reqi (s) is the corrected load force corresponding to the i-th loading device, L mi is the delay attenuation coefficient corresponding to the i-th loading device, F Rpi (s) is the nominal load force corresponding to the i-th loading device, F Ri (s) is the actual load force corresponding to the i-th loading device.

[0025] In the load control method for a steer-by-wire test bench provided in the second aspect of the present invention, obtaining the expected torque based on the corrected load force and the expected load force includes: obtaining the expected torque using an active disturbance rejection control method based on the expected load force and the corrected load force.

[0026] In the load control method for a steer-by-wire test bench provided in the second aspect of the present invention, the desired torque satisfies:

[0027] T mi =b i1 fal(e i1 ,a i1 ,κ i )+b i2 fal(e i2 ,a i2 ,κ i )+b i z i1

[0028] Where, T mi is the expected torque corresponding to the i-th loading device, b i1 , b i2 、a i1 、a i2 , κ iis the control law parameter corresponding to the i-th loading device, fal(·) is the fastest control comprehensive function, e i1 is the load force tracking error corresponding to the i-th loading device, e i2 is the first-order derivative of the load force tracking error corresponding to the i-th loading device, b i is the system parameter corresponding to the i-th loading device, z i1 is the estimated value of the system disturbance corresponding to the i-th loading device.

[0029] In the present invention, the wire steering test bench includes a comprehensive host computer, a real-time simulator, a data acquisition system, a wire steering system and a load loading system, the load loading system includes a loading sensor module, the loading sensor module includes a loading device and a tension pressure sensor, the loading device includes a load motor, a rocker arm, a connecting shaft and a load motor controller, one end of the rocker arm is fixed on the load motor, the other end of the rocker arm is mechanically connected to the connecting shaft, and the connecting shaft is also mechanically connected to one end of the wire steering system through a tension pressure sensor. The test bench connects the load motor to the connecting shaft through the rocker arm, avoids the friction and wear caused by the use of a servo motor and a cylinder sleeve, and then improves the response speed. In addition, the wire steering test bench load control method in the present invention can handle the dynamic network delay present in the wire steering test bench and improve the load simulation accuracy.

[0030] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0032] Figure 1 A block diagram of a steer-by-wire test bench provided by an embodiment of the present invention;

[0033] Figure 2 A schematic diagram of the structure of a steer-by-wire test bench provided in an embodiment of the present invention;

[0034] Figure 3 The present invention provides a flow chart of a load control method for a steer-by-wire test bench. DETAILED DESCRIPTION

[0035] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the embodiments of the present invention. Instead, they are merely examples of devices and methods consistent with some aspects of the embodiments of the present invention as detailed in the appended claims.

[0036] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0037] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. It should also be understood that the term "and / or" used in the present invention refers to and includes any or all possible combinations of one or more associated listed items.

[0038] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0039] The present invention provides a steer-by-wire test bench and a load control method to improve the response speed.

[0040] In an embodiment of the present invention, Figure 1 1 is a block diagram of a steer-by-wire test bench provided in an embodiment of the present invention. The steer-by-wire test bench in the present invention may be referred to as a test bench or a bench. Figure 1 As shown, the steer-by-wire test bench includes a host computer, a real-time simulator, a data acquisition system, a steer-by-wire system and a load loading system.

[0041] In this embodiment, the host computer is connected to the real-time simulator by communication, and the connection mode may adopt Ethernet communication mode.

[0042] In this embodiment, the host computer is used to send the driver's operation instructions to the real-time simulator, and the host computer is also used to display the test interface.

[0043] In this embodiment, the real-time simulator is connected to the data acquisition system in a communication manner, and the communication connection may be a CAN bus communication.

[0044] In this embodiment, the real-time simulator is used to receive the driver's operation instruction to obtain the expected load force, and to run the system model in real time to obtain the expected matrix using the expected load force, the nominal load force and the actual load force, thereby generating a first control instruction and a second control instruction including the expected matrix. The real-time simulator sends the first control instruction to the steer-by-wire system through the data acquisition system, and the real-time simulator sends the second control instruction to the load loading system through the data acquisition system.

[0045] In this embodiment, the data acquisition system is connected to the steer-by-wire system and the load loading system in communication, respectively. The communication connection may be CAN bus communication.

[0046] In this embodiment, the data acquisition system is used to collect sensor data in the load loading system and transfer it to the real-time simulator, and is also used to collect interface data of the real-time simulator (such as the first control instruction and the second control instruction) and transfer it to the wire-controlled steering system and the load loading system.

[0047] In this embodiment, the steer-by-wire system and the load applying system are mechanically connected.

[0048] In this embodiment, the steer-by-wire system is used to perform a steering action according to a first control instruction.

[0049] In this embodiment, the load loading system is used to dynamically load the steer-by-wire system according to the second control instruction.

[0050] In this embodiment, the load loading system includes a loading sensing module. The loading sensing module includes a loading device and a tension pressure sensor. The loading device includes a load motor, a rocker arm, a connecting shaft and a load motor controller. One end of the rocker arm is fixed to the load motor, and the other end of the rocker arm is mechanically connected to the connecting shaft. The connecting shaft is also mechanically connected to one end of the wire control steering system through the tension pressure sensor.

[0051] In this embodiment, there are multiple load sensing modules, and different load sensing modules are connected to different ends of the wire-controlled steering system. For example, the load-loading system includes two load sensing modules, and the two load sensing modules are respectively connected to the two ends of the wire-controlled steering system.

[0052] Specifically, taking the load loading system including two load sensing modules as an example, the load loading system includes a first load sensing module and a second load sensing module. The first load sensing module includes a first loading device and a first tension and pressure sensor. The second load sensing module includes a second loading device and a second tension and pressure sensor.

[0053] Figure 2 Schematic diagram of the structure of the wire steering test bench provided by the embodiment of the present invention. Figure 2 As shown, the wire steering test bench includes a host computer 1, a real-time simulator 2, a data acquisition system 3, a wire steering system 4 and a load loading system. The load loading system includes a first loading sensor module and a second loading sensor module. The first loading sensor module includes a first loading device 51 and a first tension pressure sensor 52. The second loading sensor module includes a second loading device 53 and a second tension pressure sensor 54. The host computer 1 and the real-time simulator 2 communicate via Ethernet, the real-time simulator 2 and the data acquisition system 3, the data acquisition system 3 and the wire steering system 4, the data acquisition system 3 and each loading sensor module communicate via the CAN bus, and the wire steering system 4 and each loading sensor module are mechanically connected.

[0054] The first loading device 51 includes a first load motor 511, a first rocker arm 512, a first connecting shaft 513 and a first load motor controller 514. The first loading device 51 and the first tension and pressure sensor 52 constitute a first loading sensing module. In the first loading device 51, one end of the first rocker arm 512 is fixed to the first load motor 511, and the other end of the first rocker arm 512 is mechanically connected to the first connecting shaft 513. The first connecting shaft 513 is mechanically connected to one end of the wire control steering system 4 through the first tension and pressure sensor 52.

[0055] The second loading device 53 includes a second load motor 531, a second rocker arm 532, a second connecting shaft 533, and a second load motor controller 534. The second loading device 53 and the second tension and pressure sensor 54 constitute a second loading sensing module. In the second loading device 53, one end of the second rocker arm 532 is fixed to the second load motor 531, and the other end of the second rocker arm 532 is mechanically connected to the second connecting shaft 533. The second connecting shaft 533 is mechanically connected to the other end of the wire control steering system 4 through the second tension and pressure sensor 54.

[0056] The real-time simulator 2 obtains the expected load force based on the driver's operating instructions of the upper computer 1, and obtains the expected matrix based on the expected load force, the nominal load force and the actual load force collected by the data acquisition system 3, and then generates a first control instruction and a second control instruction including the expected matrix; the real-time simulator 2 sends the first control instruction to the wire-controlled steering system 4 through the data acquisition system 3 to control the wire-controlled steering system 4 to perform steering action, and the real-time simulator 2 sends the second control instruction to the first loading device 51 and the second loading device 53 through the data acquisition system 3.

[0057] The first load motor controller 514 obtains the corresponding expected torque according to the corresponding second control instruction, and calculates the switch tube signal of the first load motor 511 driving device based on the expected torque and the actual torque of the first load motor 511 to drive the first load motor 511 to operate, so that the actual torque is the same as the expected torque, thereby realizing dynamic loading of one end of the wire-controlled steering system 4; the second load motor controller 534 obtains the corresponding expected torque according to the corresponding second control instruction, and calculates the switch tube signal of the second load motor 531 driving device based on the expected torque and the actual torque of the second load motor 531 to drive the second load motor 531 to operate, so that the actual torque is the same as the expected torque, thereby realizing dynamic loading of the other end of the wire-controlled steering system 4.

[0058] The following is an embodiment of the method of the present invention. For details not disclosed in the embodiment of the method of the present invention, please refer to the system embodiment of the present invention. The method embodiment of the present invention proposes a load control method for a steer-by-wire test bench. The load control method for a steer-by-wire test bench uses the steer-by-wire test bench of the above system embodiment to perform load control. The load control method for a steer-by-wire test bench of the present invention can be referred to as a control method.

[0059] Figure 3 The present invention provides a flow chart of a load control method for a steer-by-wire test bench.

[0060] like Figure 3 As shown, the load control method of the wire-controlled steering test bench includes:

[0061] Step S101: the host computer sends the driver's operation instruction to the real-time simulator.

[0062] In step S101, the driver's operation instruction carries the expected load force. The number of expected load forces is equal to the number of loading sensor modules, that is, each loading sensor module corresponds to one expected load force. Taking the load loading system including two loading sensor modules as an example, the driver's operation instruction carries the first expected load force and the second expected load force.

[0063] Step S102: the data acquisition system sends the actual load force acquired by the tension and pressure sensors to the real-time simulator.

[0064] In step S102, the data acquisition system and each loading sensor module communicate via the CAN bus, the tension and pressure sensors in each loading sensor module are used to monitor the actual load force of the corresponding loading device, and the data acquisition system collects the actual load force monitored by the tension and pressure sensors in each loading sensor module and sends it to the real-time simulator. Taking the load loading system including two loading sensor modules as an example, the data acquisition system sends the first actual load force monitored by the first tension and pressure sensor and the second actual load force monitored by the second tension and pressure sensor to the real-time simulator.

[0065] In step S102, after acquiring the first actual load force and the second actual load force, the real-time simulator may first filter the two actual load forces and then participate in subsequent calculations.

[0066] In step S103 , the real-time simulator obtains an expected load force based on the driver's operation instruction, and obtains an expected matrix based on the expected load force, the nominal load force and the actual load force, and then generates a first control instruction and a second control instruction.

[0067] In step S103 , the real-time simulator parses the expected load force from the driver's operation instruction.

[0068] In step S103, the real-time simulator obtains an expected matrix based on the expected load force, the nominal load force and the actual load force, including: obtaining a corrected load force based on the nominal load force and the actual load force; and obtaining an expected torque based on the corrected load force and the expected load force.

[0069] Among them, the nominal load loading system transfer function model is established in the frequency domain to obtain the nominal load force. The nominal load force satisfies:

[0070] F Rpi (s) = G i1 T mi (s)+G i2 D i (s)

[0071] In the formula, F Rpi (s) is the nominal load force corresponding to the i-th loading device, G i1 is the transfer function from the torque of the load motor corresponding to the i-th loading device to the corresponding load force, T mi (s) is the torque of the load motor corresponding to the i-th loading device, G i2 is the transfer function from the system disturbance corresponding to the i-th loading device to the corresponding load force, D i (s) is the system disturbance corresponding to the i-th loading device.

[0072] The modified load force is obtained based on the nominal load force and the actual load force, including: establishing a delay reducer according to the actual load force and the nominal load force to obtain the modified load force. The modified load force satisfies:

[0073]

[0074] In the formula, F Reqi (s) is the corrected load force corresponding to the i-th loading device, L mi is the delay attenuation coefficient corresponding to the i-th loading device, F Rpi (s) is the nominal load force corresponding to the i-th loading device, F Ri (s) is the actual load force corresponding to the i-th loading device.

[0075] Obtaining the expected torque based on the corrected load force and the expected load force includes: obtaining the expected torque using an anti-disturbance control method based on the expected load force and the corrected load force. The expected torque satisfies:

[0076] T mi =b i1 fal(e i1 ,a i1 ,κ i )+b i2 fal(e i2 ,a i2 ,κ i )+b i z i1

[0077] Where, T mi is the expected torque corresponding to the i-th loading device, b i1 , b i2 、a i1 、a i2 , κ i is the control law parameter corresponding to the i-th loading device, fal(·) is the fastest control comprehensive function, e i1 is the load force tracking error corresponding to the i-th loading device, e i2 is the first-order derivative of the load force tracking error corresponding to the i-th loading device, b i is the system parameter corresponding to the i-th loading device, z i1 is the estimated value of the system disturbance corresponding to the i-th loading device.

[0078] Taking the load loading system including the first load sensing module and the second load sensing module as an example, Figure 2 The process of obtaining the first expected matrix corresponding to the first loading sensing module and the second expected matrix corresponding to the second loading sensing module is as follows:

[0079] For the nominal load force: a nominal load loading system transfer function model is established in the frequency domain to obtain the nominal load force corresponding to the first loading device 51 and the nominal load force corresponding to the second loading device 53; wherein the nominal load loading system transfer function model satisfies:

[0080] F Rp1 (s) = G 11 T m1 (s)+G 12 D 1 (s)

[0081] F Rp2 (s) = G 21 T m2 (s)+G 22 D 2 (s)

[0082] In the formula, F Rp1 (s) is the nominal load force corresponding to the first loading device (i.e., the first nominal load force), G 11 is the transfer function from the torque of the load motor corresponding to the first loading device to the corresponding load force (i.e., the transfer function from the torque of the first load motor to the first load force), T m1 (s) is the torque of the load motor corresponding to the first loading device (i.e., the torque of the first load motor), G 12 is the transfer function from the system disturbance corresponding to the first loading device to the corresponding load force, D 1 (s) is the system disturbance corresponding to the first loading device. F Rp2 (s) is the nominal load force corresponding to the second loading device (i.e., the second nominal load force), G 21 is the transfer function from the torque of the load motor corresponding to the second loading device to the corresponding load force (i.e., the transfer function from the torque of the second load motor to the second load force), T m2 (s) is the torque of the load motor corresponding to the second loading device (i.e., the torque of the second load motor), G 22 is the transfer function from the system disturbance corresponding to the second loading device to the corresponding load force, D 2 (s) is the system disturbance corresponding to the second loading device.

[0083] For the actual load force, it should be noted that the specific formula of the actual load force transfer function model of the load loading system is:

[0084] F R (s) = G 1 T m (s)e -τs +G 2 D(s)

[0085] Among them, F R(s) is the actual load force, G 1 is the transfer function from the load motor torque to the corresponding load force, G 2 is the transfer function from system disturbance to corresponding load force, T m (s) is the torque of the load motor, and D(s) is the system disturbance. τ represents the network delay. Considering that the network delay value changes dynamically and cannot be measured during the test, the data monitored by the tension and pressure sensors are directly used as the actual load force. Subsequently, the delay reducer is introduced in combination with the nominal load force to reduce the error between the actual load force transfer function model and the data monitored by the tension and pressure sensors.

[0086] Specifically, a first delay reducer is established according to the first actual load force and the first nominal load force to obtain a first corrected load force (i.e., a corrected load force corresponding to the first loading device 51); a second delay reducer is established according to the second actual load force and the second nominal load force to obtain a second corrected load force (i.e., a corrected load force corresponding to the second loading device 53); the first corrected load force satisfies:

[0087]

[0088] In the formula, F Req1 (s) is the first modified load force; L m1 is the delay attenuation coefficient corresponding to the first loading device (i.e., the first delay attenuation coefficient), F Rp1 (s) is the nominal load force corresponding to the first loading device (i.e., the first nominal load force), F R1 (s) is the actual load force corresponding to the first loading device (ie, the first actual load force).

[0089] The second modified load force satisfies:

[0090]

[0091] In the formula, F Req2 (s) is the second modified load force; L m2 is the delay attenuation coefficient corresponding to the second loading device (i.e., the second delay attenuation coefficient), F Rp2 (s) is the nominal load force corresponding to the second loading device (i.e., the second nominal load force), F R2 (s) is the actual load force corresponding to the second loading device (ie, the second actual load force).

[0092] According to the first expected load force and the first corrected load force, the first expected torque of the first load motor 511 (i.e., the expected torque corresponding to the first loading device) is obtained by adopting the anti-disturbance control method; according to the second expected load force and the second corrected load force, the second expected torque of the second load motor 531 (i.e., the expected torque corresponding to the second loading device) is obtained by adopting the anti-disturbance control method; the first expected torque satisfies:

[0093] T m1 =b 11 fal(e 11 ,a 11 ,κ 1 )+b 12 fal(e 12 ,a 12 ,κ 1 )+b 1 z 11

[0094] Where, T m1 is the first desired torque, b 11 , b 12 、a 11 、a 12 , κ 1 is the control law parameter corresponding to the first loading device, and fal(·) is the most rapid control comprehensive function. 11 is the load force tracking error corresponding to the first loading device, e 11 =r 1 -z 1 , r 1 is the first expected load force after transition processing, z 1 is the estimated value of the first corrected load force. 12 is the first-order derivative of the load force tracking error corresponding to the first loading device, e 12 =r 2 -z 2 , r 2 is the first derivative of the first desired load force after transition processing, z 2 is the first derivative estimate of the first corrected load force. b 1 is the system parameter corresponding to the first loading device, z 11 is the estimated value of the system disturbance corresponding to the first loading device. Among them, the first desired load force after transition processing, the estimated value of the first corrected load force, the first-order derivative of the first desired load force after transition processing, and the estimated value of the first-order derivative of the first corrected load force can be obtained by the active disturbance rejection control method.

[0095] The second desired torque satisfies:

[0096] T m2 =b 21 fal(e21 ,a 21 ,κ 2 )+b 22 fal(e 22 ,a 22 ,κ 2 )+b 2 z 21

[0097] Where, T m2 is the second desired torque, b 21 , b 22 、a 21 、a 22 , κ 2 is the control law parameter corresponding to the second loading device, and fal(·) is the most rapid control comprehensive function. 21 is the load force tracking error corresponding to the second loading device, e 21 =r 3 -z 3 , r 3 is the second expected load force after transition processing, z 3 is the estimated value of the second modified load force. 22 is the first-order derivative of the load force tracking error corresponding to the second loading device, e 22 =r 4 -z 4 , r 4 is the first-order derivative of the second desired load force after transition processing, z 4 is the estimated value of the first derivative of the second corrected load force. b 2 is the system parameter corresponding to the second loading device, z 21 is the estimated value of the system disturbance corresponding to the second loading device. Among them, the second desired load force after transition processing, the estimated value of the second corrected load force, the first-order derivative of the second desired load force after transition processing, and the estimated value of the first-order derivative of the second corrected load force can be obtained by the active disturbance rejection control method.

[0098] Step S104: the steer-by-wire system performs a steering action based on the first control instruction.

[0099] Step S105 : The loading device obtains the expected torque based on the second control instruction, and drives the load motor to operate based on the expected torque to dynamically load the steer-by-wire system.

[0100] In step S105, the first loading device drives the first load motor 511 to rotate according to the expected torque corresponding to the first load motor 511, and the second loading device drives the second load motor 531 to rotate according to the expected torque corresponding to the second load motor 531. Specifically, the first load motor controller 514 obtains the first expected torque according to the corresponding second control instruction, and calculates the switch tube signal of the first load motor 511 drive device to drive the first load motor 511 based on the first expected torque and the actual torque of the first load motor 511, so as to drive the first load motor 511 to operate, so that the actual torque is the same as the first expected torque, and realizes dynamic loading of one end of the wire steering system 4; the second load motor controller 534 obtains the second expected torque according to the corresponding second control instruction, and calculates the switch tube signal of the second load motor 531 drive device to drive the second load motor 531 to operate based on the second expected torque and the actual torque of the second load motor 531, so as to make the actual torque the same as the second expected torque, and realizes dynamic loading of the other end of the wire steering system 4.

[0101] It should be noted that the aforementioned explanation of the embodiment of the steer-by-wire test bench is also applicable to the load control method of the steer-by-wire test bench of this embodiment, which will not be repeated here.

[0102] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0103] In the wire-controlled steering test bench and load control method of the embodiment of the present invention, the wire-controlled steering test bench includes an integrated host computer, a real-time simulator, a data acquisition system, a wire-controlled steering system and a load loading system, the load loading system includes a loading sensor module, the loading sensor module includes a loading device and a tension pressure sensor, the loading device includes a load motor, a rocker arm, a connecting shaft and a load motor controller, one end of the rocker arm is fixed on the load motor, the other end of the rocker arm is mechanically connected to the connecting shaft, and the connecting shaft is also mechanically connected to one end of the wire-controlled steering system through a tension pressure sensor. The test bench connects the load motor to the connecting shaft through the rocker arm, avoiding the friction and wear caused by the use of the servo motor and the cylinder sleeve, thereby improving the response speed. The moment of inertia of the load loading system in the wire-controlled steering test bench proposed by the present invention is relatively small, which can reduce the response time during the load control process and improve the load loading performance. In addition, the load control method of the present invention is a load control method for a wire-controlled steering test bench with a dynamic network delay reduction function. The delay reducer of this method can handle the dynamic network delay existing in the wire-controlled steering test bench, and can improve the load simulation accuracy of the bench dynamic load loading device; and the present invention redevelops a dynamic delay reduction algorithm based on the classic self-disturbance rejection control method, so that the control algorithm structure and design are simple and suitable for engineering applications.

[0104] The accompanying drawings show schematic diagrams of structures according to embodiments disclosed in the present invention. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0105] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution disclosed in the present invention can be achieved, and the present invention is not limited here.

[0106] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A steer-by-wire test bench, characterized in that: It includes a host computer, a real-time simulator, a data acquisition system, a wire-controlled steering system and a load loading system; the host computer is connected to the real-time simulator in communication, the real-time simulator is connected to the data acquisition system in communication, and the data acquisition system is connected to the wire-controlled steering system and the load loading system in communication; The load loading system includes a loading sensing module, which includes a loading device and a tension pressure sensor. The loading device includes a load motor, a rocker arm, a connecting shaft and a load motor controller. One end of the rocker arm is fixed to the load motor, and the other end of the rocker arm is mechanically connected to the connecting shaft. The connecting shaft is also mechanically connected to one end of the wire-controlled steering system through the tension pressure sensor.

2. The steer-by-wire test bench according to claim 1, characterized in that: There are multiple load sensing modules, and different load sensing modules are connected to different ends of the steer-by-wire system.

3. A load control method for a steer-by-wire test bench according to any one of claims 1 to 2, characterized in that: include: The host computer sends the driver's operating instructions to the real-time simulator; The data acquisition system sends the actual load force collected by the tension and pressure sensors to the real-time simulator; The real-time simulator obtains an expected load force based on the driver operation command, and obtains an expected matrix based on the expected load force, the nominal load force and the actual load force, thereby generating a first control command and a second control command; The steer-by-wire system performs a steering action based on the first control instruction; The loading device obtains the expected torque based on the second control instruction, and drives the load motor to operate based on the expected torque to dynamically load the steer-by-wire system.

4. The load control method for a steer-by-wire test bench according to claim 3, characterized in that: The obtaining of an expected matrix based on the expected load force, the nominal load force and the actual load force comprises: obtaining a corrected load force based on the nominal load force and the actual load force; A desired torque is obtained based on the corrected load force and the desired load force.

5. The load control method for a steer-by-wire test bench according to claim 3, characterized in that: The nominal load loading system transfer function model is established in the frequency domain to obtain the nominal load force.

6. The load control method for a steer-by-wire test bench according to claim 5, characterized in that: The nominal load force meets: F Rpi (s)=G i1 T mi (s)+G i2 D i (s) In the formula, F Rpi (s) is the nominal load force corresponding to the i-th loading device, G i1 is the transfer function from the torque of the load motor corresponding to the i-th loading device to the corresponding load force, T mi (s) is the torque of the load motor corresponding to the i-th loading device, G i2 is the transfer function from the system disturbance corresponding to the i-th loading device to the corresponding load force, D i (s) is the system disturbance corresponding to the i-th loading device.

7. The load control method for a steer-by-wire test bench according to claim 4, characterized in that: The obtaining a corrected load force based on the nominal load force and the actual load force comprises: A time delay attenuator is established according to the actual load force and the nominal load force to obtain a corrected load force.

8. The load control method for a steer-by-wire test bench according to claim 7, characterized in that: The modified load force satisfies: In the formula, F Reqi (s) is the corrected load force corresponding to the i-th loading device, L mi is the delay attenuation coefficient corresponding to the i-th loading device, F Rpi (s) is the nominal load force corresponding to the i-th loading device, F Ri (s) is the actual load force corresponding to the i-th loading device.

9. The load control method for a steer-by-wire test bench according to claim 4, characterized in that: The obtaining the expected torque based on the modified load force and the expected load force comprises: The expected torque is obtained by adopting an active disturbance rejection control method according to the expected load force and the corrected load force.

10. The load control method for a steer-by-wire test bench according to claim 9, characterized in that: The desired torque satisfies: T mi =b i1 false i1 ,a i1 ,k i )+b i2 false i2 ,a i2 ,k i )+b i z i1 Where, T mi is the expected torque corresponding to the i-th loading device, b i1 、b i2 、a i1 、a i2 , κ i is the control law parameter corresponding to the i-th loading device, fal(·) is the fastest control comprehensive function, e i1 is the load force tracking error corresponding to the i-th loading device, e i2 is the first-order derivative of the load force tracking error corresponding to the i-th loading device, b i is the system parameter corresponding to the i-th loading device, z i1 is the estimated value of the system disturbance corresponding to the i-th loading device.

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