Disclosure of Invention
One purpose of this application is to the steering gear system spare part abnormal deformation, fracture, not hard up and excessive wearing and tearing the trouble can be found in the early stage and in time report to the police and remind the driver to carry out troubleshooting, discern the safety risk in advance.
A further object of the present application is how to implement the hardware construction of the safety warning system based on the entire vehicle EPS steering and ABS braking system mechanism.
Particularly, the invention provides a safety early warning method for a steering transmission mechanism, which is used for sending safety early warning information when the steering transmission mechanism of a vehicle breaks down, and the safety early warning method for the steering transmission mechanism comprises the following steps:
acquiring an actual turning angle value A0 input by a steering wheel, and the left wheel speed and the right wheel speed of at least one group of wheels;
calculating left and right wheel speed differences D1, D2, and a right wheel speed difference D.a.. and Dn of the at least one group of wheels according to the left wheel speed and the right wheel speed of the at least one group of wheels, wherein D1 is the left and right wheel speed difference of a first group of wheels of the at least one group of wheels, D2 is the left and right wheel speed difference of a second group of wheels of the at least one group of wheels, and the.. a.. Dn is the left and right wheel speed difference of an nth group of wheels of the at least one group of wheels, and n is more than or equal to 1;
determining corresponding preset rotation angle values A1, A2, a... once.an from preset mapping tables of corresponding groups of wheels according to the left-right wheel speed differences D1, D2, a.once.n.Dn, wherein different left-right wheel speed differences and corresponding preset rotation angle values of a group of wheels are stored in each preset mapping table;
subtracting the actual rotation angle value A0 from the preset rotation angle values A1, A2, and A... and An to obtain delta A1, delta A2, and A... and A.;
comparing Δ a1, Δ a2, Δ An with corresponding preset thresholds, respectively, and issuing the safety precaution signal when the following conditions are met:
any one or more of Δ a1, Δ a2, a...... and Δ An exceeds the corresponding preset threshold; or
The Δ a1, Δ a2, Δ An, or Δ An obtained at a preset number of different times within a predetermined time period are different.
Optionally, in the step of obtaining the actual turning angle value a0 input by the steering wheel, the left wheel speed and the right wheel speed of at least one set of wheels, the obtaining manner of the actual turning angle value a0 comprises the following steps:
acquiring a corner signal containing a corner value and a torque signal containing a torque value, which are sent by a steering torque sensor of an EPS system of a vehicle;
and calculating the actual turning angle value A0 according to the formula A0-A0 '-B C according to the turning angle value A0', the torque value B and the steering wheel torsion bar rigidity C, wherein the steering wheel torsion bar rigidity C is constant.
Optionally, each preset mapping table is calibrated as follows:
taking m preset rotation angle values which are different;
obtaining left and right wheel speed differences corresponding to m preset rotation angle values to form a preset mapping table with the following corresponding relation: (Ai1, Di1), (Ai2, Di2), … … (Aij, Dij), … …, (Aim, Dim), wherein (Aij, Dij) represents a left-right wheel speed difference Dij corresponding to the jth preset turning angle value Aij in a preset mapping table of the ith group of wheels, i is more than or equal to 1 and less than or equal to n, and j is more than or equal to 1 and less than or equal to m;
and Dk in the left-right wheel speed difference D1, D2, Di.. and Dn is one of Di1, Di2, … … and Dim, Ak in the preset turning angle values A1, A2, a.. and An is one of Ai1, Ai2, … … and Aim, wherein k is more than or equal to 1 and less than or equal to m.
Optionally, the left and right wheel speed differences D1, D2, n are absolute values.
Optionally, Δ a1, Δ a2, and Δ An are absolute values.
In particular, the present invention further provides a steering transmission mechanism safety early warning system, configured to send safety early warning information when a steering transmission mechanism of a vehicle fails, where the vehicle includes at least one set of wheels, each set of wheels includes a left wheel and a right wheel, and the steering transmission mechanism safety early warning system includes:
at least one left wheel speed sensor for detecting a left wheel speed of the at least one set of wheels;
at least one right wheel speed sensor for detecting a right wheel speed of the at least one set of wheels;
the steering torque sensor is used for detecting a steering angle value and a torque value input by a steering wheel;
the controller is connected with the steering torque sensor, the at least one left wheel speed sensor and the at least one right wheel speed sensor, the controller comprises a memory and a processor, a control program is stored in the memory, and the control program is used for realizing the steering transmission mechanism safety early warning method when being executed by the processor.
Optionally, the at least one left wheel speed sensor and the at least one right wheel speed sensor are both disposed on the at least one set of wheels.
Optionally, the steering torque sensor is disposed within an EPS system of the vehicle.
The steering transmission mechanism safety early warning system further comprises display equipment, wherein an alarm signal lamp is arranged on the display equipment and used for giving an alarm prompt after the controller sends out the safety early warning information.
Particularly, the invention further provides a vehicle which is characterized by comprising the steering transmission mechanism safety early warning system.
According to the scheme of the invention, the fault of the steering transmission mechanism is reflected by the change of the corresponding relation between the steering angle value input by the steering wheel and the wheel speed difference of the wheels, so that the fault can be timely fed back to a driver for vehicle fault troubleshooting, traffic safety accidents caused by the fault can be effectively avoided, the safety of the steering transmission mechanism of the vehicle is greatly improved, the faults of abnormal deformation, cracking, loosening, excessive abrasion and the like of parts of the steering transmission mechanism system can be found in early stage, an alarm is timely given to prompt the driver to troubleshoot the fault, and the safety risk is recognized in advance.
Furthermore, by using a steering torque sensor and a wheel speed sensor of the vehicle, the judgment of whether the steering transmission mechanism breaks down can be realized only by the information acquired by the steering torque sensor and the wheel speed sensor, hardware equipment does not need to be newly added, and the hardware cost of the vehicle is not increased. Therefore, the technical scheme of the invention has simple and ingenious principle, is low in cost and easy to popularize and apply, and is based on the adaptive development of a hardware system of the whole vehicle.
The above and other objects, advantages and features of the present invention will become more apparent to those skilled in the art from the following detailed description of specific embodiments thereof, taken in conjunction with the accompanying drawings.
Detailed Description
FIG. 1 shows a schematic flow diagram of a steering transmission safety warning method according to one embodiment of the invention. As shown in fig. 1, the steering transmission safety early warning method includes:
step S100, acquiring an actual turning angle value A0 input by a steering wheel, and the left wheel speed and the right wheel speed of at least one group of wheels;
step S200, calculating left and right wheel speed differences D1, D2, and right wheel speed differences D2, D.a.. and Dn of at least one group of wheels according to left wheel speed and right wheel speed of at least one group of wheels, wherein D1 is the left and right wheel speed difference of a first group of wheels of at least one group of wheels, D2 is the left and right wheel speed difference of a second group of wheels of at least one group of wheels, and n is not less than 1;
step S300, corresponding preset turning angle values A1, A2, the right-to-say and An are respectively determined from preset mapping tables of corresponding groups of wheels according to the left-right wheel speed differences D1, D2, and the right-to-say-to-Dn, and different left-right wheel speed differences and corresponding preset turning angle values of a group of wheels are stored in each preset mapping table;
step S400, subtracting the actual turning angle value A0 from the preset turning angle values A1, A2, and the preset turning angle values A.gtoreq.an and An to obtain delta A1, delta A2, and delta An;
step S500, comparing the delta A1, the delta A2, the delta A.
Any one or more of Δ a1, Δ a2, ·.... and Δ An exceed a corresponding preset threshold; or
Δ a1, Δ a2, or Δ An obtained at a preset number of different times within a predetermined time period are different.
Wherein, the wheels in the at least one group of wheels are the steerable wheel group of the vehicle.
According to the scheme of the invention, the fault of the steering transmission mechanism is reflected by the change of the corresponding relation between the rotation angle value input by the steering wheel and the wheel speed difference of the wheels, so that the fault can be timely fed back to a driver for vehicle fault troubleshooting, the traffic safety accident caused by the fault can be effectively avoided, and the safety of the steering transmission mechanism of the vehicle is greatly improved.
In a specific embodiment, as shown in fig. 2, the step S100 includes:
step S110, obtaining a turning angle signal containing a turning angle value and a torque signal containing a torque value, which are sent by a steering torque sensor of the vehicle EPS system;
in step S120, an actual turning angle value a0 is calculated according to the formula a0 ═ a0 '-B × C, based on the turning angle value a 0', the torque value B, and the steering wheel torsion bar stiffness C, which is a constant.
In step S120, the steering wheel torsion bar stiffness is a fixed value, relating to the model of the steering wheel torsion bar of the vehicle. The controller uses the actual rotation angle value rather than directly using the rotation angle value directly acquired by the steering torque sensor, so that the influence of errors caused by elastic deformation of a torsion bar of the steering wheel can be avoided.
In step S200, the left-right wheel speed differences D1, D2, and D are absolute values, that is, absolute values of differences between the left wheel speed and the right wheel speed. In step S300, the preset mapping table is calibrated in the following manner: taking m preset rotation angle values which are different; obtaining left and right wheel speed differences corresponding to m preset rotation angle values to form a preset mapping table with the following corresponding relation: (Ai1, Di1), (Ai2, Di2), … … (Aij, Dij), … …, (Aim, Dim), wherein (Aij, Dij) represents a left-right wheel speed difference Dij corresponding to the jth preset turning angle value Aij in a preset mapping table of the ith group of wheels, i is more than or equal to 1 and less than or equal to n, and j is more than or equal to 1 and less than or equal to m; dk in the left-right wheel speed difference D1, D2, d.a.t., n and Dn is one of Di1, Di2, … … and Dim, Ak in the preset turning angle values A1, A2, d.a.t., n and An is one of Ai1, Ai2, … … and Aim, wherein k is more than or equal to 1 and less than or equal to m. In step S400, Δ a1, Δ a2, and Δ An are absolute values.
In some specific embodiments, the set of wheels may be, for example, one, two, or three, or even more sets. For example, when the wheel sets are in one group, i.e., i is 1, the vehicle is in a single front axle arrangement. When the wheel set is two sets, i is 2, the wheels are in a double front axle arrangement structure.
In step S500, whether it is necessary to display which set of wheels is faulty or not may be set as required, if the display is necessary, the faulty set of wheel positions may be displayed on a display device of the vehicle, such as An instrument, and if the display is not necessary, a safety warning signal may be sent out as long as one of Δ a1, Δ a2, a.
In step S500, under the condition that Δ a1, Δ a2, Δ a2, Δ a.. or Δ An obtained at different times have a preset number within a predetermined time period is different, the actual turning angle value a0 of the steering wheel input is changed in real time, that is, the value of a0 is different at different times, and safety warning information is sent out when Δ a1, Δ a2, Δ a.. or Δ An obtained at different times have a preset number different within a predetermined time period. The two conditions can be set as required, and a safety warning signal is sent as long as any one or more of a1, Δ a2, Δ An at one time exceeds the corresponding preset threshold, or safety warning information is sent only when a preset number of times of Δ a1, Δ a2, Δ a.
Fig. 3 shows a schematic diagram of a steering gear safety precaution method according to an embodiment of the invention. As shown in fig. 3, first, a left wheel speed signal including a left wheel speed, a right wheel speed signal including a right wheel speed, an EPS corner signal including a corner value, and an EPS torque signal including a torque value are transmitted to the controller, and after receiving these signals, the controller compares measured values (Ai1 ', Di1), (Ai2 ', Di2), … … (Aij ', Dij), … …, (Aim ', Dim) with corresponding values (Ai1, Di1), (Ai2, Di2), … … (Aij, Dij), … …, (Aim, Dim), and if an absolute value of Aij ' -Aij is greater than a preset threshold, a safety warning signal is issued.
According to the scheme of the embodiment of the invention, the steering torque sensor and the wheel speed sensor of the vehicle are used, and the judgment on whether the steering transmission mechanism has a fault can be realized only by using the information acquired by the steering torque sensor and the wheel speed sensor, so that hardware equipment does not need to be newly added, and the hardware cost of the vehicle is not increased. Therefore, the technical scheme of the invention has simple and ingenious principle, is low in cost and easy to popularize and apply, and is based on the adaptive development of a hardware system of the whole vehicle.
Fig. 4 shows a schematic block diagram of a steering gear safety warning system according to an embodiment of the present invention. As shown in fig. 4, the steering transmission safety warning system is used for sending safety warning information when a steering transmission of a vehicle fails. Wherein the vehicle comprises an EPS system and at least one set of wheels, each set of wheels comprising a left wheel and a right wheel. The steering transmission mechanism safety early warning system comprises at least one left wheel speed sensor 1, at least one right wheel speed sensor 2, a steering torque sensor 3 and a controller 4. The at least one left wheel speed sensor 1 is used to detect a left wheel speed in at least one set of wheels. At least one right wheel speed sensor 2 is used to detect the right wheel speed in at least one set of wheels. The steering torque sensor 3 is used to detect a steering angle value and a torque value of a steering wheel input. The controller 4 is connected with the steering torque sensor 3, the at least one left wheel speed sensor 1 and the at least one right wheel speed sensor 2, the controller 4 comprises a memory and a processor, a control program is stored in the memory, and the control program is used for realizing the steering transmission mechanism safety early warning method when being executed by the processor.
The vehicle may be, for example, a light truck, a passenger car, a heavy truck, or the like. The vehicle may comprise, for example, a single front axle or a dual front axle. The vehicle may include an EPS system and an ABS system. The EPS system comprises a steering torque sensor, and the steering torque sensor is a sensor carried by a vehicle, and is not required to be additionally added. The ABS system comprises a left wheel speed sensor and a right wheel speed sensor, and the left wheel speed sensor and the right wheel speed sensor are both sensors carried by the vehicle, so that the additional increase is not needed. The controller can realize logic functions by using the whole vehicle controller through program flashing. The instrument is additionally provided with an alarm lamp for the fault of the steering transmission mechanism, so that alarm prompt is realized.
FIG. 5 shows a schematic diagram of a steering gear safety precaution system, according to one embodiment of the present invention. As shown in fig. 5, in the safety warning system for a steering transmission mechanism, a left wheel speed sensor, a right wheel speed sensor, a steering torque sensor and a controller are all connected to a CAN line of a chassis of a whole vehicle, the left wheel speed sensor acquires a left wheel speed signal and sends the left wheel speed signal to a controller, the right wheel speed sensor acquires a right wheel speed signal and sends the right wheel speed signal to the controller, the steering torque sensor acquires an EPS torque signal and an EPS corner signal and sends the EPS torque signal and the EPS corner signal to the controller, and the controller analyzes and processes the left wheel speed signal, the right wheel speed signal, the EPS torque signal and the EPS corner signal, selectively outputs a safety warning signal, and displays the safety warning signal on an instrument.
The scheme of the invention is based on an EPS steering and ABS braking system, the input corner and torque data of a steering shaft are obtained from an EPS steering device, the wheel speed information data of left and right wheels are obtained from an ABS system, the communication is carried out through a CAN line, and the whole hardware system utilizes the whole vehicle EPS-ABS-whole vehicle controller-instrument without adding new hardware. The controller carries out logic analysis according to the information of the steering input corner sensor and the information of the wheel speed sensor, and sends an alarm signal to the instrument to give an alarm when the deviation value of the corresponding angle reaches an alarm limit.
According to the technical scheme, the fault of the steering mechanical transmission mechanism is digitally expressed through the sensor and the controller, and can be timely fed back to a driver for vehicle inspection, so that traffic safety accidents caused by the fault can be effectively avoided, and the safety of a vehicle steering system is greatly improved. The technical principle is simple and ingenious, adaptive development is carried out based on a finished automobile hardware system, the cost is low, and popularization and application are easy.
The following description is given with reference to specific examples:
the first embodiment is as follows:
in this embodiment, the steer drive is a single front axle configuration and the vehicle has a set of steerable wheels, i.e., a front left wheel and a front right wheel. In this embodiment, the preset mapping table includes the following data: (A11, D11), (A12, D12), … … (A1j, D1j), … …, (A1m, D1m), wherein m can be selected according to actual needs.
In a first safety precaution condition: for example, if the actual rotation angle value obtained through calculation is a0 and the left and right wheel speed difference is D1, if it is determined through table lookup that the D1 and D12 are equal, it is determined that the preset rotation angle value corresponding to D1 should be a12, the a12 and a0 are compared to determine whether the absolute value of the difference value between the two exceeds a preset threshold, if so, a safety warning signal is sent, otherwise, the safety warning signal is not sent.
In a second safety precaution condition: for example, at the first time, the actual rotation angle value obtained through calculation is a01, the left-right wheel speed difference D01, at the second time, the actual rotation angle value obtained through calculation is a02, the left-right wheel speed difference D02, at the third time, the actual rotation angle value obtained through calculation is a03, and the left-right wheel speed difference D03, if the values of D01 and D11 are determined to be equal through table lookup, the preset rotation angle value corresponding to D01 is determined to be a11, the values of D02 and D13 are determined to be equal, the preset rotation angle value corresponding to D02 is determined to be a13, the values of D03 and D16 are determined to be equal, the preset rotation angle value corresponding to D03 is determined to be a16, the comparison between a11 and a01 is continued, the absolute value of the difference between the two is determined to be the first difference, a13 and a02 are compared, the absolute value of the two is determined to be the second difference, the absolute value of a03 and the difference between the two is determined to be the first difference between the first difference, if the difference between the two is determined to be a16, the first difference between, And when any two of the second difference value and the third difference value exceed a preset threshold value, a safety early warning signal is sent out.
That is, in the second safety precaution condition, the actually acquired data is (a01, D01), (a02, D02), (a03, D03), the actually acquired data is compared with the data in the preset mapping table, and it should be determined which data in the preset mapping table needs to be compared first, which may be determined according to the value of the left-right wheel speed difference, and it is finally determined that the data needs to be compared with (a11, D11), (a13, D13), (a16, D16) in the preset mapping table.
Example two:
in this embodiment, the steer drive is a dual front axle configuration and the vehicle has two sets of steerable wheels, i.e., a first set of wheels comprising a first left front wheel and a first right front wheel and a second set of wheels comprising a second left front wheel and a second right front wheel. In this embodiment, the preset mapping table corresponding to the first set of wheels includes the following data: (A11, D11), (A12, D12), … … (A1j, D1j), … …, (A1m, D1m), wherein m can be selected according to actual needs. The preset mapping table corresponding to the second group of wheels comprises the following data: (A21, D21), (A22, D22), … … (A2j, D2j), … …, (A2m, D2m), wherein m can be selected according to actual needs.
In a first safety precaution condition: for example, if the actual rotation angle value obtained through calculation is a0, the left-right wheel speed difference D1 of the first group of wheels, and the left-right wheel speed difference D2 of the second group of wheels, if it is determined through table lookup that the D1 and D12 are equal in value, and the D2 and D15 are equal in value, it is determined that the preset rotation angle value corresponding to the D1 should be a12, and the preset rotation angle value corresponding to the D2 should be a15, then the a12 and the a0 are subtracted, the obtained absolute value is the first rotation angle difference value, the a15 and the a0 are subtracted, the obtained absolute value is the second rotation angle difference value, whether the first rotation angle difference value and the second rotation angle difference value exceed preset thresholds is determined, if one exceeds the first rotation angle difference value and the second rotation angle difference value exceeds the preset threshold, a safety warning signal is sent, otherwise, the safety warning signal is not sent.
In a second safety precaution condition: for example, the data actually obtained from the first group of wheels are (Aa1, Da1), (Aa2, Da2), (Aa3, Da3), the data actually obtained from the second group are (Ab1, Db1), (Ab2, Db2), (Ab3, Db3), if Da1, Da2, Da3 are equal to D12, D15, D17, respectively, the difference between Aa1 and a12 is obtained, the difference between Aa2 and a15 is obtained, the difference between Aa3 and a17 is obtained, the difference between a fifth rotation angle is obtained, and if any two or all of the difference between the third rotation angle, the difference between the fourth rotation angle, and the difference between the fifth rotation angle exceed a preset threshold, it is determined that the first group of wheels has a fault; if Db1, Db2 and Db3 are respectively equal to D21, D23 and D25, subtracting Ab1 from A21 to obtain a sixth rotation angle difference value, subtracting Ab2 from A23 to obtain a seventh rotation angle difference value, subtracting Ab3 from A25 to obtain an eighth rotation angle difference value, and if any two or all of the sixth rotation angle difference value, the seventh rotation angle difference value and the eighth rotation angle difference value exceed a preset threshold value, determining that the second group of wheels has a fault; and sending out a safety early warning signal when judging that any one group of wheels in the first group of wheels and the second group of wheels has a fault.
Thus, it should be understood by those skilled in the art that while various exemplary embodiments of the present invention have been illustrated and described in detail herein, many other variations or modifications which conform to the general principles of the invention may be directly determined or derived from the disclosure herein without departing from the spirit and scope of the invention. Accordingly, the scope of the invention should be understood and interpreted to cover all such other variations or modifications.