CN115092246A - Steering servo system and fault tolerance method thereof - Google Patents
Steering servo system and fault tolerance method thereof Download PDFInfo
- Publication number
- CN115092246A CN115092246A CN202211025301.0A CN202211025301A CN115092246A CN 115092246 A CN115092246 A CN 115092246A CN 202211025301 A CN202211025301 A CN 202211025301A CN 115092246 A CN115092246 A CN 115092246A
- Authority
- CN
- China
- Prior art keywords
- fault
- control system
- motor
- steering
- worm
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D5/00—Power-assisted or power-driven steering
- B62D5/04—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear
- B62D5/0457—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear characterised by control features of the drive means as such
- B62D5/0481—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear characterised by control features of the drive means as such monitoring the steering system, e.g. failures
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D5/00—Power-assisted or power-driven steering
- B62D5/04—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear
- B62D5/0421—Electric motor acting on or near steering gear
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D5/00—Power-assisted or power-driven steering
- B62D5/04—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear
- B62D5/0457—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear characterised by control features of the drive means as such
- B62D5/046—Controlling the motor
- B62D5/0463—Controlling the motor calculating assisting torque from the motor based on driver input
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D5/00—Power-assisted or power-driven steering
- B62D5/06—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle
- B62D5/30—Safety devices, e.g. alternate emergency power supply or transmission means to ensure steering upon failure of the primary steering means
Abstract
The invention discloses a steering servo system and a fault tolerance method thereof, which relate to the technical field of automobile steering.A first control system is only needed to complete automobile steering under normal conditions, the power of a first motor in the first control system is fully utilized, the coordination problem of the first control system and a second control system is not needed to be considered, and the control method is simplified; under the condition of a fault, the control system can be switched to a standby control system, namely a second control system, so that the fault reconstruction difficulty of the steering system is reduced. The fault grades are divided according to the danger degree possibly caused to the system after the fault of the first control system or the second control system is executed, a fault-tolerant strategy is formulated according to the fault grades and the state of the steering system, the fault reconstruction of the steering system can be rapidly completed under the condition that the first control system or the second control system is partially or completely failed, and the steering safety and the fault operability of the heavy commercial vehicle in the high-grade unmanned driving mode are guaranteed.
Description
Technical Field
The invention relates to the technical field of automobile steering, in particular to a steering servo system and a fault tolerance method thereof.
Background
The steering system widely used on the commercial vehicle is a traditional hydraulic power-assisted steering system, but has the problems of fixed power assistance ratio, poor highway feel, low energy utilization efficiency and the like, and does not have the function of assisting driving. The heavy commercial vehicle has the characteristics of large load and large steering resistance, the electric power steering system utilizes the motor to provide steering power assistance, the defects can be overcome, but the power assistance provided by the electric power steering system is relatively small, the electric power steering system is suitable for passenger vehicles but cannot meet the steering power assistance requirement of the commercial vehicle with large front axle load, the auxiliary steering or automatic steering function of the steering system is considered to be a necessary function of the unmanned commercial vehicle in the future, and once the steering is carried out, the serious consequences possibly caused by misoperation occur. The patent CN109606465A discloses the cooperation of two motors when one of the motors fails, but does not disclose the fault-tolerant method of the steering system when both motors fail.
Disclosure of Invention
1. Technical problems to be solved by the invention
Aiming at the problems, the invention provides a steering servo system and a fault tolerance method thereof, which realize fault monitoring and fault reconstruction of the steering system, enable the steering system to have failure operability, meet the intelligent driving requirement, improve the fault tolerance of the system and ensure the safety of vehicles.
2. Technical scheme
In order to solve the problems, the technical scheme provided by the invention is as follows: a fault tolerance method for a steering servo system comprises the following steps:
when the first control system has a fault and the second control system has no fault, the system works in a fault-tolerant mode, at the moment, the first control system does not work and is converted into standby, and the second control system works;
when the first control system has no fault and the second control system has a fault, the system works in a fault-tolerant mode, at the moment, the first control system works, the second control system does not work, and the system is converted into a standby mode;
when the first control system and the second control system have faults, the first control system and the second control system determine the working state according to the fault corresponding grade score: when S1 is greater than S2 and S2 is less than the fault upper limit value, the first control system does not work, and the second control system works; when S1 is less than S2 and S1 is less than the fault upper limit value, the first control system works, and the second control system does not work; when the S1 is not less than the upper limit value of the fault and the S2 is not less than the upper limit value of the fault, the first control system and the second control system do not work;
s1 is the result of weighted summation of the grades corresponding to the faults of the first control system; and S2 is the result of weighted summation of the scores corresponding to the grades when the second control system fails.
Optionally, the first control system and the second control system may be switched to each other under the three conditions that S1 < the fault upper limit value, S2 < the fault upper limit value, | S1-S2| > 2 are satisfied.
Optionally, the first control system includes a first motor and a first controller connected to the first motor, the second control system includes a second motor and a second controller connected to the second motor, the first motor and the second motor are respectively configured to be connected to the steering mechanism, the first controller is configured to obtain a working state of the first motor, torque sensor information, and first rotation angle sensor information, and the second controller is configured to obtain a working state of the second motor, torque sensor information, and second rotation angle sensor information.
Optionally, a first main control chip and a first fault diagnosis module are arranged inside the first controller, a second auxiliary control chip and a second fault diagnosis module are arranged inside the second controller, the first main control chip is connected with the first fault diagnosis module, the second auxiliary control chip is connected with the second fault diagnosis module, the first main control chip is used for acquiring a CAN bus signal, a working state of the first motor, torque sensor information and first corner sensor information, the second auxiliary control chip is used for acquiring the CAN bus signal, the working state of the second motor, torque sensor information and second corner sensor information, the first fault diagnosis module judges whether a fault occurs according to the information acquired by the first main control chip, if a fault occurs, the first fault diagnosis module performs grade division on fault types and performs score addition according to scores corresponding to the grades of the fault, obtaining S1; and the second fault diagnosis module judges whether a fault occurs according to the information acquired by the second auxiliary control chip, and if the fault occurs, the second fault diagnosis module performs grade division on the fault type and performs fraction addition according to the scores of the grades corresponding to the fault to obtain S2.
The invention also discloses a steering servo system using the fault tolerance method of the steering servo system, which comprises a first control system, a second control system, a torque sensor, a first rotation angle sensor, a second rotation angle sensor and a steering mechanism, wherein the first control system comprises a first motor and a first controller connected with the first motor, the second control system comprises a second motor and a second controller connected with the second motor, the first motor and the second motor are respectively connected with the steering mechanism, the torque sensor is arranged on the steering mechanism, and the torque sensor is respectively in communication connection with the first controller and the second controller; the first rotating angle sensor and the second rotating angle sensor are respectively arranged on the steering mechanism, the first rotating angle sensor is connected with the first controller, and the second rotating angle sensor is connected with the second controller.
Optionally, the steering mechanism includes a first worm, a second worm, a worm wheel, a torsion bar, an input shaft, an output shaft and a steering gear, the first motor is connected with the first worm, the second motor is connected with the second worm, the first worm and the second worm are respectively engaged with the worm wheel, the worm wheel sleeve is arranged on the periphery of the output shaft, one end of the output shaft is connected with the input shaft through the torsion bar, the other end of the output shaft is matched with the steering gear, a torque sensor is installed at the connecting portion of the torsion bar and the output shaft, and the first rotation angle sensor and the second rotation angle sensor are respectively arranged on the steering gear.
Optionally, the steering gear is connected with an oil pressure assembly, the oil pressure assembly comprises a hydraulic pump, an oil tank and a filter which are connected in sequence, the hydraulic pump and the filter are respectively connected with the steering gear, and an overflow valve is further arranged between the filter and the steering gear.
Optionally, a first jaw is arranged at the end of the first worm, a second jaw matched with the first jaw is arranged at the end of the first motor, a shock absorber is further arranged between the first jaw and the second jaw, the first jaw comprises a plurality of first convex blocks arranged at intervals along the circumferential direction of the end of the first worm, the second jaw comprises a plurality of second convex blocks arranged at intervals along the circumferential direction of the end of the first motor, a plurality of grooves are formed in the shock absorber at intervals along the circumferential direction of the shock absorber, and the first convex blocks and the second convex blocks are alternately matched with the grooves.
Optionally, the spreading helix angle of the first worm is greater than the friction angle of the worm wheel in contact with the first worm, and the spreading helix angle of the second worm is greater than the friction angle of the worm wheel in contact with the second worm.
3. Advantageous effects
Compared with the prior art, the technical scheme provided by the invention has the following beneficial effects:
(1) the fault tolerance method for the steering servo system, provided by the embodiment of the application, is a fault tolerance method for a steering power assisting device, and ensures that one or only one of two control systems works in a non-failure mode. The first control system comprises a first motor and a first controller connected with the first motor, the second control system comprises a second motor and a second controller connected with the second motor, under normal conditions, the automobile steering is completed only by the first control system, the power of the first motor in the first control system is fully utilized, the coordination problem of the first control system and the second control system is not required to be considered, and the control method is simplified; under the condition of a fault, the control system can be switched to a standby control system, namely a second control system, so that the difficulty of fault reconstruction of the steering system is reduced. The fault grades are divided according to the danger degree possibly caused to the system after the first control system or the second control system is executed to have faults, fault-tolerant strategies and recovery methods are formulated according to the fault grades and the states of the steering system, the fault reconstruction of the steering system can be completed quickly under the condition that the first control system or the second control system is partially or completely failed, and the steering safety and the fault operability of the heavy commercial vehicle in a high-grade unmanned driving mode are guaranteed.
Drawings
Fig. 1 is a control schematic block diagram of a fault tolerance method for a steering servo system according to an embodiment of the present invention.
Fig. 2 is a flowchart of a fault tolerance method for a steering servo system according to an embodiment of the present invention.
Fig. 3 is a schematic structural diagram of a steering servo system according to an embodiment of the present invention.
Fig. 4 is a cross-sectional view of a steering servo system according to an embodiment of the present invention.
The reference numbers in the figures are: 1. a first control system; 11. a first motor; 12. a first controller; 2. a second control system; 21. a second motor; 22. a second controller; 3. a torque sensor; 4. a first rotation angle sensor; 5. a second rotation angle sensor; 6. a steering mechanism; 61. a first worm; 62. a second worm; 63. a worm gear; 64. a torsion bar; 65. an input shaft; 66. an output shaft; 67. a diverter; 68. a first wheel; 69. a second wheel; 7. an oil pressure unit; 71. a hydraulic pump; 72. an oil tank; 73. a filter; 8. a steering wheel.
Detailed Description
For a further understanding of the present invention, reference is made to the following detailed description taken in conjunction with the accompanying drawings and examples.
The present application will be described in further detail with reference to the following drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the relevant invention and not restrictive of the invention. It should be noted that, for convenience of description, only the portions related to the present invention are shown in the drawings. The terms first, second, and the like in the present invention are provided for convenience of describing the technical solution of the present invention, have no specific limiting function, are all general terms, and do not limit the technical solution of the present invention. It should be noted that, in the present application, the embodiments and features of the embodiments may be combined with each other without conflict. In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. Unless expressly stated or limited otherwise, the terms "mounted," "connected," and "coupled" are to be construed broadly and encompass, for example, both fixed and removable coupling as well as integral coupling; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art. The technical solutions in the same embodiment and the technical solutions in different embodiments can be arranged and combined to form a new technical solution without contradiction or conflict, and the technical solutions are within the scope of the present invention.
Example 1
When the first control system 1 has a fault and the second control system 2 has no fault, the system works in a fault-tolerant mode, at the moment, the first control system 1 does not work and is converted into a standby state, and the second control system 2 works; when the first control system 1 has no fault and the second control system 2 has a fault, the system works in a fault-tolerant mode, at the moment, the first control system 1 works, the second control system 2 does not work, and the system is converted into a standby state; when the first control system 1 and the second control system 2 both have faults, the first control system 1 and the second control system 2 determine the working state according to the fault corresponding grade score: when S1 is greater than S2 and S2 is less than the fault upper limit value, the first control system 1 does not work, the second control system 2 works, and the system works in a limp home mode; when S1 is less than S2 and S1 is less than the fault upper limit value, the first control system 1 works, the second control system 2 does not work, and the system works in a limp home mode; when the S1 is not less than the upper limit value of the fault and the S2 is not less than the upper limit value of the fault, the first control system 1 and the second control system 2 do not work, the systems work in a failure mode, the health states of the two motors are poor, an automatic driving steering task cannot be executed, and the steering action is completely dependent on a driver; wherein, S1 is the result of weighted summation of the corresponding grade scores of the first control system 1 with faults; s2 is the result of weighted summation of the rank scores corresponding to the failure of the second control system 2.
The fault tolerance method for the steering servo device designed by the invention ensures that one or only one of two control systems works in a non-failure mode. The first control system 1 comprises a first motor 11 and a first controller connected with the first motor 11, the second control system 2 comprises a second motor 21 and a second controller 2 connected with the second motor 21, under normal conditions, the automobile steering is completed only by the first control system 1, the power of the first motor 11 in the first control system 1 is fully utilized, the coordination problem of the first control system 1 and the second control system 2 is not required to be considered, and the control method is simplified; under the condition of a fault, the standby control system, namely the second control system 2 can be immediately switched to, so that the difficulty of fault reconstruction of the steering system is reduced. The fault level is classified according to the danger degree possibly caused to the system after the first control system 1 or the second control system 2 is executed, a fault-tolerant strategy is formulated according to the fault level and the state of the steering system, the fault reconstruction of the steering system can be rapidly completed under the condition that the first control system 1 or the second control system 2 is partially or completely failed, and the steering safety and the fault operability of the heavy commercial vehicle in the high-grade unmanned driving mode are guaranteed. Except for the normal working mode of the system, in other modes (fault-tolerant mode, hill-going mode and failure mode), the first control system 1 and the second control system 2 need to warn a driver and store fault codes, namely after the first fault diagnosis module and the second fault diagnosis module diagnose the faults listed in the table 2, the fault codes and CAN bus communication messages of fault levels are sent to an instrument, the fault of the steering system is displayed through the instrument, and the steering system is displayed according to the severity in a grading manner. When a specific fault occurs, the first fault diagnosis module and the second fault diagnosis module can also record the fault occurrence condition, record fault codes and fault times in the whole power-on period, and store the fault codes when the power is off so as to rapidly position the fault in the process of after maintenance. In this embodiment, the calculation method of the fault corresponding grade score is as follows:
(1) grading the faults of the first control system 1 and the second control system 2
Dividing the fault of the first control system 1 into five grades of 0, 1, 2, 3 and 4, dividing the fault of the second control system 2 into five grades of 0, 1, 2, 3 and 4, wherein 0 corresponds to normal work, 1 corresponds to a slight fault, 2 corresponds to a medium fault, 3 corresponds to a serious fault, 4 corresponds to a safety fault, and the larger the number is, the higher the corresponding fault grade is, the more serious the fault is;
(2) rating fault class assignments
And respectively assigning scores to fault grades of the first control system 1 and the second control system 2, wherein the higher the fault grade is, the larger the score value is, and then the score addition is carried out according to the assigned weight, the score of the first control system 1 is S1, the score of the second control system 2 is S2, the larger the score is, the worse the health state is, and the working states of the first control system 1 and the second control system 2 are judged according to the score values. When S1 is less than S2 and S1 is less than 8, the first control system 1 works, the second control system 2 does not work, and the system works in a limp-home mode; when S1 is more than or equal to 8 and S2 is more than or equal to 8, the first control system 1 and the second control system 2 do not work.
Example 2
With reference to fig. 1-4, compared with the technical solution of embodiment 1, the fault tolerance method for the steering servo system of the present embodiment can be improved as follows: the first control system 1 and the second control system 2 are switchable with each other under the three conditions of satisfying S1 < the upper limit value of the fault, S2 < the upper limit value of the fault, | S1-S2| > 2. When the conditions that S1 is less than the fault upper limit value and S2 is less than the fault upper limit value are met, namely the system works in a normal mode, a fault-tolerant mode and a limp-home mode are ensured, the first control system 1 and the second control system 2 can be switched with each other, in order to avoid frequent switching and only switch when | S1-S2| is greater than 2, the control system with a small score before switching is prepared for switching in advance, and seamless switching is realized after the conditions are met. Each control system is provided with a corresponding control unit, the control unit is actually an advanced motor controller and is responsible for collecting sensor signals, specific power assisting and servo strategies, driving motor execution and also comprises a front end relay, so that whether the motor torque is output or not can be realized by controlling the relay of the corresponding control unit or an MOS (metal oxide semiconductor) tube of a motor driving circuit, and the switching of the two systems is controlled. The first control system and the second control system CAN mutually monitor the working states (health degree) of each other through the CAN bus to determine whether to start the control of the system.
Example 3
With reference to fig. 1-4, compared with the technical solutions of embodiments 1 or 2, the fault tolerance method for the steering servo system of the present embodiment can be improved as follows: the first control system 1 comprises a first motor 11 and a first controller connected with the first motor 11, the second control system 2 comprises a second motor 21 and a second controller 2 connected with the second motor 21, the first motor 11 and the second motor 21 are respectively connected with a steering mechanism 6, the first controller is used for acquiring the working state of the first motor 11, the information of the torque sensor 3 and the information of the first rotation angle sensor 4, and the second controller 2 is used for acquiring the working state of the second motor 21, the information of the torque sensor 3 and the information of the second rotation angle sensor 5. The first steering motor controller and the second steering motor controller can respectively acquire signals of voltage, current, a motor position sensor, temperature, a relay working state, a driving circuit working state and the like of the first steering motor and the second steering motor, and a vehicle speed message, an oil pump working state and an automatic driving control message are transmitted by the whole vehicle.
Example 4
With reference to fig. 1 to 4, compared with any of the technical solutions of embodiments 1 to 3, the fault tolerance method for the steering servo system of the present embodiment can be improved as follows: a first main control chip and a first fault diagnosis module are arranged in the first controller, a second auxiliary control chip and a second fault diagnosis module are arranged in the second controller 2, the first main control chip is connected with the first fault diagnosis module, the second auxiliary control chip is connected with the second fault diagnosis module, the first main control chip is used for acquiring CAN bus signals, the working state of the first motor 11, the information of the torque sensor 3 and the information of the first corner sensor 4, the second auxiliary control chip is used for acquiring CAN bus signals, the working state of the second motor 21, the information of the torque sensor 3 and the information of the second corner sensor 5, the first fault diagnosis module judges whether a fault occurs according to the information acquired by the first main control chip, if the fault occurs, the first fault diagnosis module grades the fault types and performs fractional addition according to the assigned weights of the fault corresponding grades, obtaining S1; and the second fault diagnosis module judges whether a fault occurs according to the information acquired by the second auxiliary control chip, if the fault occurs, the second fault diagnosis module grades the fault type and performs score addition according to the assigned weights of the corresponding grades of the fault to obtain S2. The faults comprise over-low or over-high temperature, over-limit vehicle speed, loss of vehicle speed messages, abnormity of wheel corner sensors, jumping of vehicle speed messages, abnormity of torque sensors 3, abnormity of power supply voltage, jumping of target corners, abnormity of message verification, abnormity of motor current, failure of relays, abnormity of controller current signals, over-high temperature sensor signals, loss of oil pump working messages, over-limit target corners, loss of automatic driving control messages, failure of motor driving circuits and faults of motor position sensors. See tables 1 and 2 specifically:
| fault of Grade | Assignment of value Weight of | Level description | Description of processing |
| 0 | 0 | Normal operation | Without |
| 1 | 1 | |
1. The fault has little effect on the |
| 2 | 2 | |
1. The fault occurrence has |
| 3 | 4 | |
1. The fault has a large influence on the |
| 4 | 8 | |
1. The fault affects the |
TABLE 1
| Serial number | Failure class | Meaning of |
| 1 | |
Low |
| 2 | |
|
| 3 | |
Vehicle speed message loss |
| 4 | |
Abnormality of second rotation angle sensor of |
| 5 | |
The difference between the rotation angle values of the first rotation angle sensor and the second rotation angle sensor of the wheel is large |
| 6 | |
Vehicle speed message hopping |
| 7 | |
Second |
| 8 | |
Wheel first angle sensor abnormality |
| 9 | |
Supply voltage is too high |
| 10 | |
Low supply voltage |
| 11 | |
|
| 12 | |
Control message check exception of electric control system |
| 13 | |
First torque sensor abnormality |
| 14 | |
Current abnormality of motor |
| 15 | |
Failure of relay |
| 16 | |
Controller current signal anomaly |
| 17 | |
Over-high signal of temperature sensor |
| 18 | |
Loss of oil pump working message |
| 19 | |
Target turning angle exceeding upper limit |
| 20 | Class 4 fault | Autonomous driving control message loss |
| 21 | Class 4 fault | Failure of motor drive circuit |
| 22 | Class 4 fault | Motor position sensor failure |
TABLE 2
Example 5
With reference to fig. 1 to 4, a steering servo system of this embodiment, using the fault tolerance method of the steering servo system according to any one of the technical solutions of embodiments 1 to 4, includes a first control system 1, a second control system 2, a torque sensor 3, a first rotation angle sensor 4, a second rotation angle sensor 5, and a steering mechanism 6, where the first control system 1 includes a first motor 11 and a first controller connected to the first motor 11, the second control system 2 includes a second motor 21 and a second controller 2 connected to the second motor 21, the first motor 11 and the second motor 21 are respectively connected to the steering mechanism 6, the torque sensor 3 is disposed on the steering mechanism 6, and the torque sensor 3 is respectively connected to the first controller and the second controller 2 in communication; the first rotation angle sensor 4 and the second rotation angle sensor 5 are respectively arranged on the steering mechanism 6, the first rotation angle sensor 4 is connected with the first controller, and the second rotation angle sensor 5 is connected with the second controller 2. The torque sensor 3 is adapted to receive a steering wheel torque signal, the first steering angle sensor 4 is adapted to receive a first wheel 68 steering angle signal, and the second steering angle sensor 5 is adapted to receive a second wheel steering angle signal.
Example 6
With reference to fig. 1 to 4, the steering servo system of the present embodiment can be improved as follows compared with any of the technical solutions of embodiments 1 to 5: the steering mechanism 6 comprises a first worm 61, a second worm 62, a worm wheel 63, a torsion bar 64, an input shaft 65, an output shaft 66 and a steering gear 67, the first motor 11 is connected with the first worm 61, the second motor 21 is connected with the second worm 62, the first worm 61 and the second worm 62 are respectively meshed with the worm wheel 63, the worm wheel 63 is sleeved on the periphery of the output shaft 66, one end of the output shaft 66 is connected with the input shaft 65 through the torsion bar 64, the other end of the output shaft 66 is matched with the steering gear 67, a torque sensor 3 is installed at the connecting part of the torsion bar 64 and the output shaft 66, and the first rotation angle sensor 4 and the second rotation angle sensor 5 are respectively arranged on the steering gear 67. The steering wheel is connected with one end of an input shaft 65, the other end of the input shaft 65 is connected with the input shaft 65 through a torsion bar 64, and the torque sensor 3 is used for acquiring a rotation angle and a torque signal of the steering wheel and sending the rotation angle and the torque signal to the first controller and the second controller 2; the first controller and the second controller 2 are used for receiving the rotation angle and the torque signal and respectively controlling the first motor 11 and the second motor 21 to output target torques.
Example 7
With reference to fig. 1 to 4, the steering servo system of the present embodiment can be improved as follows compared with any of the embodiments 1 to 6: the hydraulic assembly 7 is connected to the steering gear 67, the hydraulic assembly 7 comprises a hydraulic pump 71, an oil tank 72 and a filter 73 which are sequentially connected, the hydraulic pump 71 and the filter 73 are respectively connected with the steering gear 67, and a relief valve is further arranged between the filter 73 and the steering gear 67. The hydraulic oil in the oil tank 72 is sent to the steering gear 67 after being boosted by the hydraulic pump 71, and is sent to the corresponding hydraulic oil cylinder through a rotary valve in the steering gear 67 during left-right steering to provide steering power; meanwhile, the low-pressure oil of the hydraulic oil cylinder flows through a transfer valve of the steering gear 67, is filtered by the filter 73 and then flows back to the oil tank 72, and the overflow valve is closed at the moment; when the oil pressure is too high, the relief valve is opened, and the hydraulic oil in excess flows back to the oil tank 72 directly through the relief valve and the filter 73.
Example 8
With reference to fig. 1 to 4, the steering servo system of the present embodiment can be improved as follows compared with any of the embodiments 1 to 7: the tip of first worm 61 is equipped with first jack catch, the tip of first motor 11 be equipped with first jack catch complex second jack catch, still be equipped with the bumper shock absorber between first jack catch and the second jack catch, first jack catch includes a plurality of first lugs that set up along the circumference interval of first worm 61 tip, the second jack catch includes a plurality of second lugs that set up along the circumference interval of first motor 11 tip, the bumper shock absorber is equipped with a plurality of recesses along self circumference interval, first lug and second lug are in turn with the recess cooperation. The shock absorber connects the first jaw and the second jaw together, prevents the first jaw and the second jaw from being separated from each other, and ensures that the first motor 11 and the first worm 61 synchronously rotate in the process of transmitting motion and power.
Example 9
With reference to fig. 1 to 4, the steering servo system of the present embodiment can be improved as follows compared with any of the embodiments 1 to 8: the helix angle of the first worm 61 is greater than the friction angle between the worm wheel 63 and the first worm 61, and the helix angle of the second worm 62 is greater than the friction angle between the worm wheel 63 and the second worm 62. The condition that the worm gear 63 worm drive cannot self-lock is that the helix angle of the worm is greater than the angle of friction of the worm gear 63 worm contact. That is β > Φ, β is the deployment helix angle of the first worm 61 or the second worm 62, Φ is the friction angle; tg Φ = μ, μ is the coefficient of friction. The output shaft 66 is mounted on a bearing seat of the flange in a bearing mode, the shaft end is positioned through a clamp spring and a locking nut, and the output shaft 66 is in transition fit with the output shaft. The input shaft 65 is in bearing transition fit with the input shaft 65, and the input shaft 65 is mounted on a bearing seat of a cover of the torque sensor 3 in a bearing mode.
The present invention and its embodiments have been described above schematically, without limitation, and what is shown in the drawings is only one of the embodiments of the present invention, and the actual structure is not limited thereto. Therefore, if the person skilled in the art receives the teaching, without departing from the spirit of the invention, the person skilled in the art shall not inventively design the similar structural modes and embodiments to the technical solution, but shall fall within the scope of the invention.
Claims (9)
1. A fault tolerance method for a steering servo system is characterized by comprising the following steps:
when the first control system has a fault and the second control system has no fault, the system works in a fault-tolerant mode, at the moment, the first control system does not work and is converted into standby, and the second control system works;
when the first control system has no fault and the second control system has a fault, the system works in a fault-tolerant mode, at the moment, the first control system works, the second control system does not work, and the system is converted into a standby mode;
when the first control system and the second control system have faults, the first control system and the second control system determine the working state according to the corresponding grade scores of the faults: when S1 is greater than S2 and S2 is less than the fault upper limit value, the first control system does not work, and the second control system works; when S1 is less than S2 and S1 is less than the fault upper limit value, the first control system works, and the second control system does not work; when the S1 is not less than the upper limit value of the fault and the S2 is not less than the upper limit value of the fault, the first control system and the second control system do not work;
s1 is the result of weighted summation of the grades corresponding to the faults of the first control system; s2 is the result of the weighted summation of the corresponding grade scores for the second control system failure.
2. The fault-tolerant method for the steering servo system according to claim 1, wherein the first control system and the second control system are switched with each other under the conditions that S1 < the upper limit value of the fault, S2 < the upper limit value of the fault, | S1-S2| > 2 are satisfied.
3. The fault tolerant method of a steering servo system according to claim 1, wherein the first control system comprises a first motor and a first controller connected to the first motor, the second control system comprises a second motor and a second controller connected to the second motor, the first motor and the second motor are respectively used for being connected to the steering mechanism, the first controller is used for acquiring an operating state of the first motor, torque sensor information and first rotation angle sensor information, and the second controller is used for acquiring an operating state of the second motor, torque sensor information and second rotation angle sensor information.
4. The fault tolerant method for the steering servo system according to claim 3, wherein a first main control chip and a first fault diagnosis module are arranged in the first controller, a second auxiliary control chip and a second fault diagnosis module are arranged in the second controller, the first main control chip is connected with the first fault diagnosis module, the second auxiliary control chip is connected with the second fault diagnosis module, the first main control chip is used for obtaining CAN bus signals, the working state of the first motor, torque sensor information and first rotation angle sensor information, the second auxiliary control chip is used for obtaining CAN bus signals, the working state of the second motor, torque sensor information and second rotation angle sensor information, the first fault diagnosis module judges whether a fault occurs according to the information obtained by the first main control chip, if the fault occurs, the first fault diagnosis module carries out grade division on the fault types and carries out score addition according to scores of corresponding grades of the faults to obtain S1; and the second fault diagnosis module judges whether a fault occurs according to the information acquired by the second auxiliary control chip, and if the fault occurs, the second fault diagnosis module performs grade division on the fault type and performs fraction addition according to the scores of the grades corresponding to the fault to obtain S2.
5. A steering servo system using the fault tolerance method of the steering servo system according to any one of claims 1 to 4, comprising a first control system, a second control system, a torque sensor, a first rotation angle sensor, a second rotation angle sensor and a steering mechanism, wherein the first control system comprises a first motor and a first controller connected with the first motor, the second control system comprises a second motor and a second controller connected with the second motor, the first motor and the second motor are respectively connected with the steering mechanism, the torque sensor is arranged on the steering mechanism, and the torque sensor is respectively connected with the first controller and the second controller in a communication way; the first rotating angle sensor and the second rotating angle sensor are respectively arranged on the steering mechanism, the first rotating angle sensor is connected with the first controller, and the second rotating angle sensor is connected with the second controller.
6. The steering servo system according to claim 5, wherein the steering mechanism comprises a first worm, a second worm, a worm wheel, a torsion bar, an input shaft, an output shaft and a steering gear, the first motor is connected with the first worm, the second motor is connected with the second worm, the first worm and the second worm are respectively meshed with the worm wheel, the worm wheel is sleeved on the periphery of the output shaft, one end of the output shaft is connected with the input shaft through the torsion bar, the other end of the output shaft is matched with the steering gear, a torque sensor is mounted at the connection part of the torsion bar and the output shaft, and the first rotation angle sensor and the second rotation angle sensor are respectively arranged on the steering gear.
7. The steering servo system according to claim 6, wherein an oil pressure assembly is connected to the steering gear, the oil pressure assembly comprises a hydraulic pump, an oil tank and a filter which are connected in sequence, the hydraulic pump and the filter are respectively connected with the steering gear, and a relief valve is further arranged between the filter and the steering gear.
8. The steering servo system according to claim 6, wherein a first jaw is arranged at the end of the first worm, a second jaw is arranged at the end of the first motor and is matched with the first jaw, a shock absorber is further arranged between the first jaw and the second jaw, the first jaw comprises a plurality of first lugs which are arranged at intervals along the circumferential direction of the end of the first worm, the second jaw comprises a plurality of second lugs which are arranged at intervals along the circumferential direction of the end of the first motor, the shock absorber is provided with a plurality of grooves at intervals along the circumferential direction of the shock absorber, and the first lugs and the second lugs are alternatively matched with the grooves.
9. The steering servo system according to claim 6, wherein a deployment helix angle of the first worm is larger than a friction angle at which the worm wheel contacts the first worm, and a deployment helix angle of the second worm is larger than a friction angle at which the worm wheel contacts the second worm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211025301.0A CN115092246B (en) | 2022-08-25 | 2022-08-25 | Steering servo system and fault tolerance method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211025301.0A CN115092246B (en) | 2022-08-25 | 2022-08-25 | Steering servo system and fault tolerance method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115092246A true CN115092246A (en) | 2022-09-23 |
| CN115092246B CN115092246B (en) | 2022-11-11 |
Family
ID=83300954
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211025301.0A Active CN115092246B (en) | 2022-08-25 | 2022-08-25 | Steering servo system and fault tolerance method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115092246B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002200952A (en) * | 2000-12-28 | 2002-07-16 | Fuji Heavy Ind Ltd | Steering system failure diagnosing device of automobile |
| CN109606461A (en) * | 2017-10-04 | 2019-04-12 | 操纵技术Ip控股公司 | Triplex level redundancy fault secure for steering system |
| CN112770958A (en) * | 2020-12-25 | 2021-05-07 | 华为技术有限公司 | Control method, monitoring method, electronic control unit, controller and control system |
| JP2021125890A (en) * | 2020-01-31 | 2021-08-30 | 日本電産エレシス株式会社 | Motor control device |
| CN114043995A (en) * | 2021-11-22 | 2022-02-15 | 江苏大学 | Fault-tolerant device and fault-tolerant control method for autonomous steering system of unmanned vehicle |
-
2022
- 2022-08-25 CN CN202211025301.0A patent/CN115092246B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002200952A (en) * | 2000-12-28 | 2002-07-16 | Fuji Heavy Ind Ltd | Steering system failure diagnosing device of automobile |
| CN109606461A (en) * | 2017-10-04 | 2019-04-12 | 操纵技术Ip控股公司 | Triplex level redundancy fault secure for steering system |
| JP2021125890A (en) * | 2020-01-31 | 2021-08-30 | 日本電産エレシス株式会社 | Motor control device |
| CN112770958A (en) * | 2020-12-25 | 2021-05-07 | 华为技术有限公司 | Control method, monitoring method, electronic control unit, controller and control system |
| CN114043995A (en) * | 2021-11-22 | 2022-02-15 | 江苏大学 | Fault-tolerant device and fault-tolerant control method for autonomous steering system of unmanned vehicle |
Non-Patent Citations (1)
| Title |
|---|
| 荣芩等: "基于ISO标准的道路车辆线控转向系统的功能安全概念设计", 《汽车安全与节能学报》 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115092246B (en) | 2022-11-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112590921B (en) | Intelligent automobile redundant steer-by-wire device and control method thereof | |
| JP5816019B2 (en) | Control device for steer-by-wire steering system with redundancy function | |
| US9533703B2 (en) | Vehicle steering device | |
| EP1332083B1 (en) | Method for controlling a steer-by-wire system | |
| CN101549707B (en) | Automobile steering-by-wire redundancy and fault tolerance system and control method | |
| EP3810486B1 (en) | Motor vehicle steering system with a control unit of redundant configuration | |
| CN111762260B (en) | Power-assisted steering system redundancy control system and method based on calibrated vehicle speed and vehicle | |
| CN109466621B (en) | Three-motor steer-by-wire system and control method thereof | |
| WO2009082994A1 (en) | Clutch actuator and method for the control thereof | |
| CN209870491U (en) | Electrohydraulic steering gear with redundant motor for advanced automatic driving tool | |
| CN105050883A (en) | Independent supplementary electrically assisted power steering system | |
| Harter et al. | Future electrical steering systems: Realizations with safety requirements | |
| WO2006063680A1 (en) | Method for monitoring and device for operating a transmission oil pump | |
| CN112660235A (en) | Redundant power steering system, control method thereof and vehicle | |
| CN110027612A (en) | Commercial vehicle and its steering system | |
| CN108698630A (en) | The calculating of fail safe for improving servo steering device and function structure system | |
| JPH01257682A (en) | Rear wheel steering device for vehicle | |
| CN110588767A (en) | Multi-motor redundancy device and control method of wire-controlled steering system | |
| CN115092246B (en) | Steering servo system and fault tolerance method thereof | |
| WO2011026457A1 (en) | Clutch actuator | |
| CN109204450B (en) | Dual-motor electric power steering system and steering method based on electromagnetic clutch | |
| JP6591283B2 (en) | Vehicle steering device | |
| EP3084253B1 (en) | Method for increasing the availability of a hybrid separating clutch in a hybrid drive train of a motor vehicle | |
| CN110949492B (en) | Wire-controlled steering fault-tolerant device and control method thereof | |
| WO2007122102A1 (en) | Power steering system for vehicles |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |