CN115923835A - Drive-by-wire chassis system for unmanned driving and control method - Google Patents
Drive-by-wire chassis system for unmanned driving and control method Download PDFInfo
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Abstract
The invention discloses a drive-by-wire chassis system for unmanned driving and a control method, and relates to the technical field of unmanned driving. The invention comprises a steer-by-wire subsystem, wherein the steer-by-wire subsystem comprises a steer-by-wire module and a corner sensor; the brake-by-wire subsystem is characterized in that the brake-by-wire subsystem comprises a brake-by-wire module, an angle sensor and a brake switch; the drive-by-wire clutch subsystem comprises a drive-by-wire clutch module and a clutch matching module; the shift-by-wire subsystem comprises a shift-by-wire module and a shift matching module; the system comprises a domain controller module, a control module and a control module, wherein the domain controller module comprises a drive-by-wire chassis domain controller and a drive-by-wire accelerator; the wire control chassis domain controller comprises a plurality of CAN communication interfaces, ADC interfaces, DAC interfaces, a plurality of GPIO input interfaces and a plurality of GPIO output interfaces. According to the invention, the wire control chassis domain controller software adopts a layered architecture and a modular design, so that the complexity of the system is reduced, and the reliability is improved.
Description
Technical Field
The invention belongs to the technical field of unmanned driving, and particularly relates to a drive-by-wire chassis system for unmanned driving and a control method.
Background
With the continuous development and progress of the unmanned technology, the unmanned vehicle has been applied in a specific field and gradually tends to be "practical" by "experiments. The drive-by-wire chassis technology is the premise of unmanned realization, and the invention can realize the drive-by-wire chassis function of old fuel-powered vehicles (especially manual transmission vehicles). There is currently no relevant patent that provides a systematic solution for manual range fuel powered vehicle drive-by-wire chassis retrofit.
The by-wire chassis control system solution is based on an automatic transmission, in patent publication CN 112677903. The patent publication No. CN112319601 does not include control schemes related to clutch and gear shift, and the control method of the drive-by-wire chassis includes only functions of steering-by-wire, braking, and parking, and does not consider a fault diagnosis and a fault handling related control method when a system or a component fails, so that a highly safe drive-by-wire chassis system is required.
Disclosure of Invention
The invention aims to provide a drive-by-wire chassis system for unmanned driving and a control method thereof.
In order to solve the technical problems, the invention is realized by the following technical scheme:
the invention relates to a drive-by-wire chassis system for unmanned driving and a control method thereof, comprising a drive-by-wire steering subsystem, wherein the drive-by-wire steering subsystem comprises a drive-by-wire steering module and a corner sensor for a steering wheel; the brake-by-wire subsystem comprises a brake-by-wire module, an angle sensor and a brake switch; the drive-by-wire clutch subsystem comprises a drive-by-wire clutch module and a clutch matching module; a shift-by-wire subsystem comprising a shift-by-wire module, and a shift engagement module; the system comprises a domain controller module, a control module and a control module, wherein the domain controller module comprises a drive-by-wire chassis domain controller and a drive-by-wire accelerator; the drive-by-wire chassis domain controller comprises a plurality of CAN communication interfaces, ADC interfaces for digital-to-analog conversion, DAC interfaces for analog-to-digital conversion, a plurality of GPIO input interfaces for collecting signals and a plurality of GPIO output interfaces for outputting signals.
As a preferred technical scheme of the invention, the clutch matching module comprises a position sensor and a clutch switch or comprises a reversing valve and a hydraulic pipeline; when the position sensor and the clutch switch are adopted, the wire control clutch module comprises a motor and a gear and drives the pressing rod to press the clutch pedal arm to realize the treading of the clutch pedal; the clutch switch adopts the original vehicle clutch switch, and the line control chassis system can operate under the condition of no clutch switch signal; when a reversing valve and a hydraulic pipeline are adopted, the wire control clutch module comprises a clutch master cylinder, an electric cylinder, a bracket, a linear bearing, a guide shaft, a limiting sleeve and a connecting seat; the clutch master cylinder adopts the clutch master cylinder with the same model or the same specification as the original vehicle, and the original vehicle clutch slave cylinder is switched to be driven by the clutch master cylinder of the line control clutch module through the reversing valve and the hydraulic pipeline.
As a preferred technical scheme of the invention, the gear shifting matching module comprises a flexible shaft and a gear shifting knob or consists of a cantilever type mechanical arm, a mounting bracket and a gear shifting knob.
As a preferred technical scheme of the invention, the line control chassis domain controller comprises CAN communication interfaces which are respectively used for connecting an original vehicle CAN bus and used for information interaction between nodes in the line control chassis domain; the CAN communication interface connected with the original vehicle CAN bus is used for reading the rotating speed information fed back by the ECU and the vehicle speed information fed back by the ABS.
As a preferred technical solution of the present invention, the drive-by-wire chassis domain controller includes 6 ADC interfaces respectively used for acquiring sensor voltage signals of an electronic accelerator, a brake-by-wire position sensor, and a clutch-by-wire position sensor.
As a preferred technical solution of the present invention, the drive-by-wire chassis domain controller includes a 2-way DAC interface for outputting an analog voltage signal of the control accelerator.
As a preferred technical scheme of the invention, the GPIO input interface is used for acquiring a gear request signal, a driving mode switch signal, a brake switch signal and a clutch switch state signal; and the GPIO output interface is used for respectively outputting an ignition relay signal, a flameout relay signal, a parking relay signal, a state indicator lamp control signal and a gear mode state feedback signal.
The invention also provides a control method for the unmanned drive-by-wire chassis system, which comprises the following steps: s1, performing information interaction between application layer software and bottom layer software through a preset data interface, and transmitting information such as ADC (analog to digital converter) sampling data, CAN (controller area network) communication bus data, GPIO (general purpose input pin) states, bottom layer software zone bits and the like to an input module of the application layer software through the data interface by the bottom layer software; the application layer software comprises an input module, a functional module and an output module; the functional modules comprise a fault diagnosis module, a fault processing module, a mode management module, a gear management module and a chassis control module; the output module comprises a subsystem control parameter module, a CAN communication parameter module, a hardware output parameter module, a delay data module and a data interface module; the bottom layer software also comprises a timer, a drive-by-wire subsystem control module and an equipment driving module; s2, filtering analog quantity signals and digital quantity signals in the input module; and S3, adding a debugging interface to the key data, and sending the key data to a data preprocessing submodule for data preprocessing.
As a preferred technical solution of the present invention, the filtering process in step S2 includes the following steps: a1, performing low-pass filtering processing on 2-path accelerator pedal voltage signals; a2, performing mean value filtering processing on the voltage signals of the line control moving position sensor 2; a3, performing mean value filtering processing on the voltage signals of the 2-line clutch position control sensor; and A4, performing mean value filtering processing on the power supply voltage signal.
As a preferred technical solution of the present invention, the data preprocessing in step S3 includes the following steps: a) Calculating the speed and the acceleration; b) Calculating the brake-by-wire opening and the brake switch state; c) Calculating the clutch opening and the clutch switch state of the drive-by-wire; d) Calculating the current gear; e) Calculating the working state of the engine; f) Calculating a gear shifting state zone bit; the method comprises the following steps of checking the reasonability of gears according to the instantaneous vehicle speed, and specifically comprises the following steps: if the current gear is in the 1 gear, the N gear or the R gear, directly outputting a check result of 0x1; the current gear is located in other gears, the corresponding engine rotating speed is calculated in a reverse pushing mode according to the instantaneous vehicle speed, the current gear speed ratio, the transmission system speed ratio and the wheel rolling radius, if the rotating speed is larger than 1000rpm, the verification is passed, the verification result flag bit =0x1 is output, and if the verification is not passed, the verification result flag bit =0x0 is output; g) Calculation of driver target gear modes, such as R, N and D modes; h) And (5) filtering the corner of the target steering wheel.
The invention has the following beneficial effects:
1. according to the invention, the wire control chassis domain controller software adopts a layered architecture and a modular design, a series of flag bits are used for data transmission among different modules, the working state of the wire control chassis is subdivided in the mode management module, and classification control is implemented in the chassis control module according to the working state of the wire control chassis, so that the system complexity is reduced, the maintenance and the upgrade are easy, and the software reliability is improved.
2. The system has perfect fault diagnosis and treatment measures by arranging the fault diagnosis module and the fault treatment module, and can effectively avoid the damage to vehicles and personnel when the abnormal conditions such as subsystem failure and the like are met.
3. The system adopts a modular design, and has the characteristics of wide applicability, small change to vehicles, short software calibration period and the like when being matched with different types of vehicles.
4. The system has compact structure of each module, small occupied space and no influence on manual driving of a driver after being deployed to a vehicle.
5. The system is designed by considering the unidirectional decoupling operation of manual braking and automatic braking in the automatic driving state, the driver can perform manual braking intervention at any time in the automatic driving state, and when the driver relieves the braking dry state, the system can automatically recover to operate, so that the safety is ensured, and the stability of the system operation is also considered.
6. The system embeds the debugging interface according to the preset simple communication protocol, and improves the development and debugging efficiency.
Of course, it is not necessary for any product in which the invention is practiced to achieve all of the above-described advantages at the same time.
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In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a schematic structural diagram of a drive-by-wire chassis system for unmanned driving according to the present invention;
FIG. 2 is a data flow diagram of a control method for an unmanned drive-by-wire chassis system of the present invention;
FIG. 3 is a schematic diagram of a debug interface algorithm;
FIG. 4 is a schematic diagram of a schema management algorithm;
FIG. 5 is a schematic diagram of a schema management algorithm;
FIG. 6 is a schematic diagram of a schema management algorithm;
FIG. 7 is a schematic diagram of a schema management algorithm;
FIG. 8 is a schematic diagram of a state switching algorithm;
fig. 9 is a schematic structural diagram of a gear management algorithm.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example one
Referring to fig. 1, the present invention relates to a steer-by-wire chassis system for unmanned driving and a control method thereof, comprising a steer-by-wire subsystem, wherein the steer-by-wire subsystem comprises a steer-by-wire module and a steering angle sensor for a steering wheel; the steer-by-wire subsystem is composed of a steer-by-wire module and a steering wheel corner sensor, wherein the steer-by-wire module comprises a hollow shaft motor, a bracket, a spline shaft, a spline sleeve and other components, the bracket is provided with a mounting position of the steering wheel corner sensor, and the spline sleeve is provided with a clamping structure of the steering wheel corner sensor; when a drive-by-wire chassis system is modified, the drive-by-wire steering module replaces an original vehicle steering wheel, the original vehicle steering wheel is assembled on a steering column through spline connection, and the original vehicle steering wheel is fixed with a rotor of a hollow shaft motor through a spline housing; for the vehicle type of which the original vehicle is not provided with the steering wheel angle sensor, the steering wheel angle sensor is added and is arranged at a preset position on the bracket; the brake-by-wire subsystem comprises a brake-by-wire module, an angle sensor and a brake switch; the control rotor system consists of a brake-by-wire module, an angle sensor and a brake switch, wherein the brake-by-wire module comprises an integrated motor, a speed reducer, a bracket, a pinion, a fan-shaped tooth, a pressure lever and other components, the bracket is provided with a position sensor mounting position, and the fan-shaped tooth is provided with a position sensor clamping structure; the brake switch adopts the original vehicle brake switch, and the line-control chassis system can operate under the condition of no brake switch signal, but cannot recognize the manual brake intervention of a driver; when the wire-controlled chassis system is modified, the wire-controlled brake module is arranged near a brake pedal, a pressure lever is contacted with the original vehicle brake pedal arm, and the brake pedal is stepped down by pressing down the pressure lever; the drive-by-wire clutch subsystem comprises a drive-by-wire clutch module and a clutch matching module; a shift-by-wire subsystem comprising a shift-by-wire module, and a shift-fit module; the system comprises a domain controller module, a control module and a control module, wherein the domain controller module comprises a drive-by-wire chassis domain controller and a drive-by-wire accelerator; the drive-by-wire chassis domain controller comprises a plurality of CAN communication interfaces, ADC interfaces for digital-to-analog conversion, DAC interfaces for analog-to-digital conversion, a plurality of GPIO input interfaces for acquiring signals and a plurality of GPIO output interfaces for outputting signals, a drive-by-wire steering module, a drive-by-wire brake module, a drive-by-wire clutch module, a drive-by-wire gear shifting module and a domain controller module, wherein the drive-by-wire accelerator function is realized by the ADC and DAC functions of the domain controller module, and the drive-by-wire chassis domain controller controls steering, braking, clutching and gear shifting subsystems through a CAN bus and monitors the working state of the drive-by-wire chassis domain controller.
Referring to fig. 1, the clutch matching module includes a position sensor and a clutch switch or includes a reversing valve and a hydraulic line; when the position sensor and the clutch switch are adopted, the wire control clutch module comprises a motor and a gear and drives the pressing rod to press down the clutch pedal arm, so that the clutch pedal is treaded down; the clutch switch adopts the original vehicle clutch switch, and the line control chassis system can operate under the condition of no clutch switch signal; when a reversing valve and a hydraulic pipeline are adopted, the wire control clutch module comprises a clutch master cylinder, an electric cylinder, a bracket, a linear bearing, a guide shaft, a limiting sleeve and a connecting seat; the invention provides a systematic solution for improving the functions of a drive-by-wire chassis of an old fuel powered vehicle, in particular a manual transmission vehicle. The gear shifting matching module comprises a flexible shaft and a gear shifting knob or a cantilever type mechanical arm, a mounting bracket and a gear shifting knob.
Referring to fig. 1, the drive-by-wire chassis domain controller includes a CAN communication interface for connecting the original vehicle CAN bus and for information interaction among nodes in the drive-by-wire chassis domain, including CDCU, ADS, SAS, SCM, BCM, CCM, GSEM, and GSHM, respectively; the controller software of the drive-by-wire chassis domain adopts a layered architecture and a modular design, a series of zone bits are used for data transmission among different modules, the working state of the drive-by-wire chassis is subdivided in the mode management module, and classification control is implemented in the chassis control module according to the working state of the drive-by-wire chassis, so that the system complexity is reduced, the maintenance and the upgrade are easy, and the software reliability is improved.
Wherein each abbreviation means as follows:
1) And (3) CDCU: a Chassis Domain control unit (wire control);
2) ADS: autonomous Driving System, autopilot System;
3) An ECU: engine Control Uint, engine Control unit;
4) ABS: anti-lock Braking System, anti-lock Braking System;
5) SAS: steering Angle Sensor, steering wheel Angle Sensor;
6) SCM: steering-by-wire Module;
7) BCM: a Braking Control Module, a brake-by-wire Module;
8) CCM: a Clutch Control Module and a line Control Clutch Module;
9) GSEM: gear Select Motor, drive-by-wire Gear Select Motor;
10 GSHM): gear Shift Motor, shift-by-wire Motor;
11 ADC): analog-to-Digital, digital-to-Analog conversion;
12 DAC): digital-to-Analog, analog-to-Digital conversion.
The drive-by-wire chassis domain controller comprises 6 paths of ADC interfaces which are respectively used for collecting voltage signals of an electronic throttle, a drive-by-wire brake position sensor and a drive-by-wire clutch position sensor. The drive-by-wire chassis domain controller comprises a 2-path DAC interface used for outputting an analog voltage signal of the control accelerator.
The GPIO input interface is used for acquiring a gear request signal, a driving mode switch signal, a brake switch signal and a clutch switch state signal; and the GPIO output interface is used for respectively outputting an ignition relay signal, a flameout relay signal, a parking relay signal, a state indicator lamp control signal and a gear mode state feedback signal.
Example two
On the basis of the first embodiment, the invention further provides a control method for the unmanned drive-by-wire chassis system, which comprises the following steps: s1, performing information interaction between application layer software and bottom layer software through a preset data interface, and transmitting information such as ADC (analog to digital converter) sampling data, CAN (controller area network) communication bus data, GPIO (general purpose input pin) states, bottom layer software zone bits and the like to an input module of the application layer software through the data interface by the bottom layer software; the application layer software comprises an input module, a functional module and an output module; the system has perfect fault diagnosis and treatment measures, and can effectively avoid the damage to vehicles and personnel in the face of abnormal conditions such as subsystem failure and the like; the output module comprises a subsystem control parameter module, a CAN communication parameter module, a hardware output parameter module, a delay data module and a data interface module; the bottom layer software also comprises a timer, a drive-by-wire subsystem control module and an equipment driving module; s2, filtering analog quantity signals and digital quantity signals in the input module; and S3, adding a debugging interface to the key data, and sending the key data to a data preprocessing submodule for data preprocessing.
The filtering process in step S2 includes the steps of: a1, performing low-pass filtering processing on 2-path accelerator pedal voltage signals; a2, performing mean value filtering processing on the voltage signals of the line control moving position sensor 2; a3, performing mean value filtering processing on the voltage signals of the 2-line clutch position control sensor; and A4, performing mean value filtering processing on the power supply voltage signal.
The data preprocessing in the step S3 comprises the following steps: a) Calculating the speed and the acceleration; b) Calculating the brake-by-wire opening and the brake switch state; c) Calculating the clutch opening and the clutch switch state of the drive-by-wire; d) Calculating the current gear; e) Engine operating conditions such as shut-down, calculation of operation; f) Calculating a gear shifting state zone bit; the method comprises the following steps of checking the reasonability of gears according to the instantaneous vehicle speed, and specifically comprises the following steps: if the current gear is in the 1 gear, the N gear or the R gear, directly outputting a check result of 0x1; the current gear is located in other gears, the corresponding engine rotating speed is calculated in a reverse pushing mode according to the instantaneous vehicle speed, the current gear speed ratio, the transmission system speed ratio and the wheel rolling radius, if the rotating speed is larger than 1000rpm, the verification is passed, a verification result flag bit =0x1 is output, otherwise, the verification is not passed, and the verification result flag bit =0x0 is output; g) Calculation of driver target gear modes, such as R, N and D modes; h) And (5) filtering the corner of the target steering wheel.
The application also provides a core algorithm controlled by the system:
regarding the debug interface:
2 global variable arrays with the length of 256 are preset in bottom-layer software, wherein the data type of Cali _ Switch [ ] is Byte, the initial value of all array elements is 0x0, the data type of Cali _value [ ] is Uint32, and the initial value of all array elements is 0x0.
As shown in fig. 3, when a debug message Rx [ ] with a length of 7 is received on the CAN bus, after passing the verification, the underlying software assigns a value of the 1 st byte Rx [1] of the CAN message to Cali _ Switch [ Index ], that is, cali _ Switch [ Rx [0] ] = Rx [1], by using the 0 th byte Rx [0] of the CAN message as an Index (Index); converting the 2 nd, 3 rd, 4 th and 5 th bytes of the CAN message from high to low into Uint32 type data, and then giving Cali _ Value [ Index ], namely Cali _ Value [ Rx [0] ] = ((Uint 32) Rx [2] < < 24) | ((Uint 32) Rx [3] < < 16) | ((Uint 32) Rx [4] < < 8) | ((Uint 32) Rx [5 ]); the 6 th byte Rx 6 of the CAN message is a check byte based on the CRC-8 check algorithm of SAEJ 1850.
Debugging interfaces (at most 255) are preset in application layer software in a mode of pre-allocating identification tags (Tag) to each input signal, and the default tags are 0 and represent that no debugging interface exists. When the Tag Value (1-255) of a certain input signal corresponds to the Index Value (Index) in the debugging message received by the underlying software and the debugging Switch (Cali _ Switch) is turned on, the Value is covered by the actual Value converted by Cali _ Value.
Array elements of Cali _ Value [ ] are shaping storage values, each array element is preset with precision and offset in application layer software, and the storage values are multiplied by the precision plus the offset to be converted into floating point type actual values.
Regarding fault diagnosis and handling:
the chassis-by-wire system presets a range of different fault types including: the power supply is slightly under-voltage, the power supply is seriously under-voltage, the power supply is over-voltage, the clutch separation is overtime, the reset neutral gear is overtime, the gear selection is overtime, the gear shifting is overtime, the clutch loading is overtime, the voltage of the 1 st path of the electronic throttle is over-limit, the voltage of the 2 nd path of the electronic throttle is over-limit, the voltage of the two paths of signals is over-limit, the rationality fault of the two paths of signals is overtime, the CAN communication of the steering motor is lost, the fault of the steering motor is overtime, the CAN communication of the corner sensor is lost, the communication of the CAN of the corner sensor is lost, the fault of the CAN of the corner sensor is overtime, the communication of the CAN of the brake motor is lost, the position of the brake motor is abnormal, the position of the brake angle sensor is failed, the CAN communication of the clutch motor is overtime, the communication of the clutch motor is lost, the fault of the clutch motor is failed, the CAN of the gear selection motor is overtime, the communication of the CAN of the gear selection motor is overtime, the CAN is overtime, the communication of the gear selection motor is lost, the CAN is overtime, the ECU communication is overtime, the CAN is overtime, the communication of the ECU is overtime, the CAN, the communication of the CAN communication of the ECU is overtime, the ADS communication is lost, the ADS communication is overtime, the ADS communication is lost.
Wherein:
the CDCU diagnoses and identifies the power supply micro undervoltage, the power supply serious undervoltage and the power supply overvoltage faults according to the power supply voltage signal ADC sampling value and a preset threshold value;
the CDCU adds a timer in the corresponding state of the mode management state machine for diagnosis and identification of clutch separation overtime, reset neutral overtime, gear selection overtime, gear shifting overtime and clutch loading overtime faults;
the CDCU diagnoses and identifies the 1 st path voltage overrun of the electronic accelerator, the 2 nd path voltage overrun of the electronic accelerator, the two paths of voltage overrun and the two paths of signal rationality faults according to the ADC sampling value of the electronic accelerator pedal voltage signal and a preset threshold value;
the fault of the brake angle sensor is diagnosed and identified by the CDCU according to the sampling value of the voltage signal ADC of the brake-by-wire position sensor and a preset threshold value;
a steering motor fault, a corner sensor fault, a clutch motor fault, a gear selection motor fault and a gear shifting motor fault are read from a CAN bus by a CDCU, and fault messages fed back by the nodes of the line control subsystem are analyzed for diagnosis and identification;
the CDCU reads and analyzes a motor position value fed back by the wire control gear shifting module and a preset threshold value from a CAN bus to diagnose and identify the position abnormality of the gear selecting motor and the position abnormality fault of the gear shifting motor;
the CAN communication overtime and CAN communication loss faults of the wire control chassis system nodes are diagnosed and identified by the CDCU according to the following algorithm (taking ECU CAN communication diagnosis as an example):
1) Defining CANR _ ECU _ Rolling (Byte type) and CANR _ ECU _ RxFlag (Byte type) variables;
2) Adding 1 to CANR _ ECU _ Rolling after the bottom layer software receives one frame of ECU message, and setting 0 to CANR _ ECU _ Rolling to prevent overflow when CANR _ ECU _ Rolling is more than 250;
3) Performing Delay processing on CANR _ ECU _ Rolling in application layer software to obtain CANR _ ECU _ Rolling _ Delay1, and performing Delay processing on CANR _ ECU _ Rolling _ Delay1 to obtain CANR _ ECU _ Rolling _ Delay2;
4) Judging by the application layer software every 10ms, when CANR _ ECU _ Rolling is not equal to CANR _ ECU _ Rolling _ Delay1 or CANR _ ECU _ Rolling is not equal to CANR _ ECU _ Rolling _ Delay2 transmitted by the underlying layer software and any condition is met, setting CANR _ ECU _ RxFlag to 0x1, otherwise, when CANR _ ECU _ Rolling is equal to CANR _ ECU _ Rolling _ Delay1 and CANR _ ECU _ Rolling is equal to CANR _ ECU _ Rolling _ Delay2, setting CANR _ ECU _ RxFlag to 0x0;
5) Digital filtering and jitter elimination are carried out on the CANR _ ECU _ RxFlag signal, when the CANR _ ECU _ RxFlag is equal to 0x0 and the duration is more than 15 operation periods (150 ms), an ECU CAN communication overtime fault is triggered, and when the duration is more than 30 operation periods (300 ms), an ECU CAN communication loss fault is triggered; in the counting period that CANR _ ECU _ RxFlag is equal to 0x0, if CANR _ ECU _ RxFlag in any operation period is equal to 0x1, the counter is cleared;
according to different severity of faults, the recovery modes of the faults are different, for slight faults, such as power supply micro undervoltage, ECU CAN communication overtime and other faults, when the voltage and CAN communication are recovered, the faults are automatically cleared, and for serious faults, such as power supply serious undervoltage, ECU CAN communication loss and other faults, the faults need to be powered on again after power is off and the faults are cleared to be recovered.
The drive-by-wire chassis system presets a series of different fault handling measures, including: the speed limit is 20km/h, the throttle limit is 20%, the throttle limit is 0%, the gear limit is N, automatic driving is forbidden, the enabling of a gear selecting and shifting motor is forbidden, emergency braking is carried out, and the like.
And defining a fault handling matrix aiming at each specific fault, and adopting different fault handling measures according to the manual/automatic driving state respectively. For example: when an ECU CAN communication loss fault occurs and the drive-by-wire chassis system is in a manual driving state, taking measures of limiting an accelerator by 0 percent, limiting a gear by N gear and forbidding entering automatic driving; when the ECU CAN communication loss fault occurs and the drive-by-wire chassis system is in an automatic driving state, the automatic driving state CAN not be exited by taking the measures of throttle limitation of 0% and gear limitation of N gear, and at the moment, the drive-by-wire brake, the drive-by-wire steering and the like CAN still work. The CDCU outputs zone bit signals of various processing measures through a fault processing module, and corresponding limiting measures are implemented according to the zone bit signals in a mode management module, a gear management module and a chassis control module.
Special fault treatment:
1) When the position of the gear selecting and shifting motor is abnormal, the processing measures such as limiting the accelerator by 0%, limiting the gear by N and the like are adopted, and the processing measures of forbidding the gear selecting and shifting motor to enable are also adopted to avoid damaging the gearbox;
2) When an ADS CAN communication loss fault occurs and the drive-by-wire chassis system is in an automatic driving state, emergency braking treatment measures are required besides treatment measures of throttle limitation of 0%, gear limitation of N gear and the like; the emergency braking processing algorithm comprises the following steps:
a) When the CDCU identifies the ADS CAN communication loss fault, the CDCU latches the instantaneous vehicle speed;
b) The CDCU obtains a brake pedal opening degree change gradient limiting value (maximum increment per 10 ms) from a preset MAP by looking up a table according to the latched instantaneous vehicle speed when the fault occurs;
c) The CDCU gradually increases the target brake pedal opening degree until the target brake pedal opening degree reaches 100% according to the gradient limiting value;
pattern management
The mode management module of the CDCU comprises a Trigger signal processing module and a state machine module, wherein the CDCU calculates a system initialization completion flag bit, an automatic driving entering flag bit, an automatic driving exiting flag bit and an automatic driving braking demand flag bit in the Trigger module and is used for judging state switching conditions in the subsequent state machine module.
The CDCU defines 40 drive-by-wire chassis working modes, and carries out state switching management through a 4-layer state machine, wherein the state switching management comprises the following steps:
the first layer state machine divides the system operation state into three types: initialization, manual Driving and Auto Driving, wherein the system is in an initialization state by default after being powered on; when the system initialization completion flag bit is equal to 1, the working state of the drive-By-wire chassis is switched to Manual _ Driving, and the state of the default state MD _ Stand _ By (Manual Driving-standby) of the embedded second-layer state machine is entered; when the automatic Driving entering zone bit is equal to 1, the working state of the drive-by-wire chassis is switched from Manual _ Driving to Auto _ Driving, and according to the states of an engine and the vehicle speed, the drive-by-wire chassis enters the states of Stall (automatic Driving-flameout), parkking (automatic Driving-Parking), stop (automatic Driving-Parking) or Driving (automatic Driving-Driving) of a built-in second-layer state machine; when the automatic Driving quit flag bit is equal to 1, the drive-By-wire chassis working state is switched back to Manual _ Driving By Auto _ Driving and enters a default state MD _ Stand _ By (Manual Driving-standby) state of an embedded second-layer state machine.
The embedded second-layer state machine of the Manual _ Driving state machine comprises two states of MD _ Stand _ By and Manual _ Shifting, wherein the MD _ Stand _ By is a default state, and when a target gear is inconsistent with a current gear and an engine is in an operating state, the operating state of the drive-By-wire chassis is switched to the Manual _ Shifting state; and when the target gear is consistent with the current gear and the gear Shifting completion flag bit is equal to 1, the drive-By-wire chassis working state is switched back to the MD _ Stand _ By state By Manual _ Shifting.
The third layer of state machine embedded in Manual _ Shifting is a Shifting state machine, the Shifting process is subdivided into six sub-states of Unload, clutch release, restore, select, shift, load and Finish, counters are used for timing in the states of Unload, restore, select, shift, gear and Load, and when the counters exceed a threshold value and still do not enter the next flow state, clutch release timeout, reset neutral timeout, gear selection timeout, gear Shifting timeout and clutch loading timeout faults are respectively triggered.
Entry into Restore state condition by Unload: the opening degree of an accelerator pedal is less than or equal to 10, and the opening degree of a clutch pedal is more than or equal to 60;
restore enters Select _ Gear state condition: the opening degree of an accelerator pedal is less than or equal to 10, the opening degree of a clutch pedal is greater than or equal to 60, and a reset neutral gear completion flag bit is =1;
select _ Gear enter Shift _ Gear state condition: the opening degree of an accelerator pedal is less than or equal to 10, the opening degree of a clutch pedal is more than or equal to 60, and a gear selection completion flag bit = =1;
shift _ Gear enters Load State Condition: the opening degree of an accelerator pedal is less than or equal to 10, the opening degree of a clutch pedal is greater than or equal to 60, a gear shifting completion flag position is =1, and the checking of the rationality of gears passes the flag position =1;
load enters Finish state condition: the opening degree of a clutch pedal is less than or equal to 5, or (the opening degree of the clutch pedal is more than or equal to 60, and the state of a brake switch is not larger than = is pressed down);
before the Shift _ Gear state is switched to the Load state, gear rationality check is carried out according to the current instantaneous vehicle speed (check operation is carried out in a preprocessing module, and a check result flag bit is output to a mode management module for condition judgment), if the check is not passed, the Shift state is returned, gear selection and Gear shifting processes are carried out again, and a ReShiftFlag flag bit 1 output by a state machine is transmitted to a subsequent Gear management module.
The third-layer state machine Braking _ Down Shifting and the fourth-layer state machine Driving _ Shifting embedded in the Auto _ Driving respectively correspond to Braking DownShifting and Shifting in the normal Driving process, the flow and the logic of the method are completely consistent with those of Manual _ Shifting, and enumerated values of the working states of the drive-by-wire chassis are different.
As shown in fig. 7, when the Auto _ Driving state machine is first entered, if the engine is in a flameout state, the working state of the drive-by-wire chassis system is switched to a Stall state, otherwise, the Parking state flag bit is continuously determined, if the Parking state flag bit is in the Parking state, the park state is switched to, otherwise, the vehicle speed is continuously determined, if the vehicle speed is less than or equal to 6km/h, the Stop state is switched to, and otherwise, the Driving state is switched to.
The state switching conditions are explained as follows:
(1) the method comprises the following steps Engine operation flag bit = =1;
(2) the method comprises the following steps An engine operation flag bit = =1, and a parking state flag bit = =1;
(3) the method comprises the following steps An engine operation zone bit = =1, a parking state zone bit = =0, and a vehicle speed is less than or equal to 6km/h;
(4) the method comprises the following steps An engine operation flag bit = =1, and a parking state flag bit = =0, and a vehicle speed > 6km/h;
(5) the method comprises the following steps A misfire instruction = =1, or (target vehicle speed = =0, and duration > 120 s);
(6) the method comprises the following steps Current gear = = N gear, and target vehicle speed = =0;
(7) the method comprises the following steps A flameout command = =1, and a parking state flag bit = =1;
(8) the method comprises the following steps Ignition command = =1, and current gear = = N gear, and gear confirmation flag = =1;
(9) the method comprises the following steps A fire-out command = =1, or a fire failure flag bit = =1;
r: an ignition success flag bit = =1, and a parking state flag bit = =1;
stall, crank, park, stop, braking _ D, braking _ R, and reforming no-child states as described above;
a sub-state machine is embedded in the PreParking state, and the gear is set to be N gear according to the procedures of Unload, restore and Finish;
embedding a sub-state machine into a Half _ Clutch _ D state machine, setting the Gear to be 1 Gear according to Unload, restore, select _ Gear, shift _ Gear and creating processes, maintaining the Gear in a creating state, and performing semi-linkage control by a chassis control module; if the gear is in the 1-gear position when the state machine is entered, skipping the previous process and directly entering a planting state; the process is similar to a Gear shifting process, overtime diagnosis is also carried out on Unload, restore, select _ Gear and Shift _ Gear, but a target Gear is fixed to a Gear 1 and Gear rationality check is not carried out any more;
a sub-state machine is embedded into a Half-cut _ R state machine, the process is similar to the Half-cut _ D state machine, the difference is that the gear is changed from 1 gear to R gear, the process is finally maintained in the HCR _ creating state, and a chassis control module performs Half-linkage control;
the Braking _ shifting state machine is internally provided with a shifting sub-state machine as described above, and is mainly used for performing downshift according to the vehicle speed descending condition before the driving state is recovered from the Braking state in the automatic driving process;
the process is similar to that of a Prebraking state, if Braking is needed in the automatic driving gear Shifting process, the Shifting _ Prebraking state is entered first to place gears in an N gear, and then the Braking _ D state is entered, no matter a working mode of a drive-by-wire chassis system is in the Shifting _ Prebraking or the Braking _ D state, a chassis control module can perform Braking control according to a target vehicle speed requirement, and the reset N gear in the Shifting _ Prebraking state is parallel to the Braking control, so that the Braking response speed cannot be influenced;
a Driving state embedded sub-state machine, as shown in fig. 8:
the state switching conditions are explained as follows:
(1) the method comprises the following steps The target vehicle speed is greater than the current vehicle speed +3;
(2) the method comprises the following steps Brake demand flag bit = =1;
(3) the method comprises the following steps Brake demand flag bit = =1;
(4) the method comprises the following steps Brake demand flag bit = =1;
(5) the method comprises the following steps The target vehicle speed is greater than the current vehicle speed +3;
(6) the method comprises the following steps The target vehicle speed is less than or equal to the current vehicle speed +1;
(7) the method comprises the following steps The gear shifting completion flag bit is =1, and the target vehicle speed is less than or equal to the current vehicle speed +3;
(8) the method comprises the following steps Target gear! = current gear;
(9) the method comprises the following steps The gear shifting completion flag bit is =1, and the target vehicle speed is greater than the current vehicle speed +3;
r: target gear! = current gear;
when the difference between the target vehicle speed and the current vehicle speed is greater than a threshold value, entering an accelerating state, and using an acceleration closed loop in a chassis control module to control the output of an accelerator pedal;
when the difference between the target vehicle speed and the current vehicle speed is smaller than a threshold value, entering a cruise state, and using a vehicle speed closed loop in a chassis control module to control the output of an accelerator pedal;
a hysteresis interval is reserved between the 2 thresholds, so that the state machine is prevented from jumping back and forth, and jitter is eliminated;
in the Accelating state or the Cruising state, when the brake demand flag bit = =1, the state machine jumps out of the Driving state and directly enters the Braking _ D state;
in a Driving Shifting state, when a Braking demand flag bit is =1, a state machine jumps out of the Driving state and enters a Shifting-prebaking state firstly, and then enters a Braking-D state after a gear is shifted to an N gear;
gear management
The gear management module comprises a target gear mode calculation submodule and a target gear position calculation submodule.
Target gear mode calculation module
Under the target gear mode calculation module, respectively calculating target gear modes under the states of initialization, manual driving and automatic driving according to the working mode states of the line control chassis system output by the mode management module:
in an initialization state (a drive-by-wire chassis system working mode state = = Initializing), a target gear mode is locked to be an N-gear mode;
in a manual driving state (the working mode state of the drive-By-wire chassis system is not more than MD _ Load and not more than MD _ Stand _ By), if the engine is in a flameout state, the target gear mode is locked to be an N gear mode, otherwise, the target gear mode is switched according to the driver target gear mode, the current vehicle speed and the brake switch state which are calculated and output By the preprocessing module according to the state machine shown in the figure 9:
the state switching conditions are explained as follows:
(1) the method comprises the following steps (driver target gear mode = = D range mode and current vehicle speed > 0) or (driver target gear mode = = D range mode and current vehicle speed = =0 and brake switch state = = depressed);
(2) the method comprises the following steps Driver target gear pattern = = N-gear pattern, or driver target gear pattern = = R-gear pattern;
(3) the method comprises the following steps (driver target gear pattern = = R range pattern and current vehicle speed < 0) or (driver target gear pattern = = R range pattern and current vehicle speed = =0 and brake switch state = = depressed);
(4) the method comprises the following steps Driver target gear mode = = N-gear mode, or driver target gear mode = = D-gear mode;
under the automatic driving state (Stall is less than or equal to the working mode state of the drive-by-wire chassis system is less than or equal to Reversing):
if the working mode state of the wire control chassis system is less than or equal to park, the target gear mode is an N gear mode;
if the working mode state of the wire control chassis system is smaller than Parking and smaller than or equal to PP _ Restore, the target gear mode is a D gear mode;
if the PP _ Restore is less than the working mode state of the wire-controlled chassis system and is less than or equal to Reversing, the target gear mode is an R gear mode;
target gear position calculation module
The gear positions corresponding to the N gear mode and the R gear mode are respectively an N gear and an R gear, and the forward gear target gear position (1-6 gears) in the D gear mode is calculated according to the following method:
1) According to the opening degree of an accelerator pedal and the current gear position, calculating corresponding upshift speed and downshift speed by looking up a table;
2) According to the current vehicle speed, based on the gear-up and gear-down vehicle speed threshold values, calculating a target gear position, wherein the lowest gear position is a gear 1 and the highest gear position is a gear 6;
3) When the working state mode of the wire control chassis output by the state management module enters a gear shifting process state due to the fact that the target gear position is not consistent with the current gear position, the calculation of the target gear position is suspended, and the target gear position is latched until the gear shifting process is finished;
4) When the state management module transmits ReShiftFlag (the gear rationality check does not pass the re-shifting flag bit) = =0, outputting the target gear position calculated in the step 2);
5) When the state management module transmits ReShiftFlag = =1, determining a target gear position according to the current vehicle speed: when the vehicle speed is less than or equal to 15km/h, the target gear position is 1 gear, when the vehicle speed is less than or equal to 26km/h and less than or equal to 15km/h, the target gear position is 2 gear, when the vehicle speed is less than or equal to 35km/h and less than or equal to 26km/h, the target gear position is 3 gear, when the vehicle speed is less than or equal to 40km/h and less than or equal to 35km/h, the target gear position is 4 gear, when the vehicle speed is less than or equal to 40km/h and less than or equal to 40km/h, the target gear position is 5 gear, and when the vehicle speed is more than 50km/h, the target gear position is 6 gear;
chassis control
The chassis control module comprises 5 sub-modules of wire-controlled throttle control, wire-controlled brake control, wire-controlled clutch control, wire-controlled gear selection control and wire-controlled gear shifting control.
Throttle by wire control
If the working mode of the drive-by-wire chassis system is in an initialization or manual driving state, directly using the voltage signal of the electronic accelerator pedal of the original vehicle sampled and filtered by the input module as the DAC control parameter of the drive-by-wire accelerator, and calculating the corresponding opening degree of the accelerator pedal according to the voltage signal table look-up, and outputting the opening degree of the accelerator pedal as the target opening degree of the accelerator pedal to a subsequent module;
if the working mode of the drive-by-wire chassis system is in the automatic driving mode, firstly calculating the opening degree of a target accelerator pedal, and then calculating a corresponding voltage signal according to a table look-up of the opening degree of the pedal to be used as a DAC (digital-to-analog converter) control parameter of the drive-by-wire accelerator; the target accelerator pedal opening degree in the automatic driving mode is calculated as follows:
1) When the working mode of the drive-by-wire chassis system is in the gear shifting process or in the braking state, the target accelerator pedal opening degree is 0%;
3) When the working mode of the drive-by-wire chassis system is in a D-gear or R-gear semi-linkage state, taking 850rpm as a target rotating speed, carrying out closed-loop control on the rotating speed of an engine, and limiting the maximum opening degree of a target accelerator pedal not to exceed 20%;
4) When the work mode of the wire-controlled chassis system is in a Cruising (cruise) state, carrying out vehicle speed closed-loop control by using a target vehicle speed sent by the ADS, wherein the P-item coefficient is calculated according to a target vehicle speed value table, and the higher the vehicle speed is, the larger the driving resistance is, and the P-item coefficient is properly increased;
5) When the working mode of the drive-by-wire chassis system is in a Reversing (Reversing) state, vehicle speed closed-loop control is carried out according to a target vehicle speed sent by the ADS, and the difference from the vehicle speed closed-loop control in the Cruising state is that the coefficients of the P item and the I item are fixed values which can be calibrated, and the coefficients cannot be changed in the program running process;
6) When the working mode of the drive-by-wire chassis system is in an acceleration (acceleration) state, calculating the required acceleration by looking up a table according to the target speed and the current speed difference sent by the ADS, and performing acceleration closed-loop control;
7) When the brake switch state = = is pressed, no matter what working state the system is in, the target accelerator pedal opening is limited to 0%;
brake-by-wire control
Calculating the opening degree of a target brake pedal according to the working mode state of the drive-by-wire chassis system;
when in an initialization or manual driving state, the brake-by-wire system does not work, namely the opening degree of a target brake pedal is 0 percent;
in the working mode of the drive-by-wire chassis system in the automatic driving mode, in the processes of semi-linkage, cruising, accelerating, backing and gear shifting, the target brake pedal opening degree is also 0 percent;
in the parkking state: when the parking completion flag bit = =0, the previous brake pedal state is maintained, and when the parking completion flag bit = =1, the target brake pedal opening degree is 0%, and the service brake is released;
under the states of Crank, stop, PP _ Unload-PP _ Restore: the opening degree of the target brake pedal is locked to be 80%, and the treading state is kept;
in the states of Braking _ D, SPB _ Unload-SPB _ Restore: according to the difference value between the target vehicle speed and the current vehicle speed, calculating the target brake pedal opening degree by looking up a table;
in Braking _ R state: similar to the state of Braking _ D, calculating the opening degree of a target brake pedal by looking up a table, wherein the difference is that the calibration values of the horizontal coordinate and the vertical coordinate of the MAP by looking up the table are different;
in other states, maintaining the opening value of the target brake pedal in the previous operation period unchanged;
line controlled clutch control
Calculating the opening degree of a target clutch pedal according to the working mode state of the drive-by-wire chassis system;
in the states of Initializing and Stall-parkking, the opening degree of a target clutch pedal is 0 percent;
under the conditions of Cruising-Accelarating and Reversing, when the rotating speed of the engine is less than or equal to 850rpm, the opening value of a target clutch pedal is locked to 80 percent, and the engine is prevented from flameout due to manual brake intervention; when the brake switch state is not = released and the engine speed is greater than 850rpm, the target clutch pedal opening value is decreased according to a preset clutch release gradient value until the minimum limit value is 0%;
in the MD _ Stand _ By state, when the engine speed is less than or equal to 720rpm or the brake switch state = = is pressed, the target clutch pedal opening value is locked to be 80%; when the engine speed is greater than 720rpm and the brake switch state = = release, the target clutch pedal opening value is decreased according to a preset clutch release gradient value until the minimum limit value is 0%;
in the gear shifting process or in the Stop state, the opening value of the target clutch pedal is locked to be 80 percent;
in the Load (MD _ Load, DS _ Load and BDS _ Load) state of the gear shifting process, when the engine speed is less than or equal to 720rpm or the brake switch state = = is pressed, the target clutch pedal opening value is locked to 80%; when the rotating speed of the engine is more than 720rpm and the brake switch state = = release, the opening value of the target clutch pedal is decreased according to a preset clutch release gradient value until the minimum limit value is 0%;
in the states of Braking _ D and Braking _ R, the initial target clutch pedal opening degree is 0%, when the rotating speed of the engine is less than or equal to 1200rpm, the target clutch pedal opening degree is locked at 80%, and the unlocking is not carried out until the state of the Braking _ D or the Braking _ R is exited and the state is entered again;
under the HCD _ creating state, when the target vehicle speed is less than the current vehicle speed, or the engine speed is less than or equal to 720rpm, or (the brake switch state = = is stepped on, and the opening of the brake-by-wire pedal is less than or equal to 1%), the opening value of the target clutch pedal is locked to 80%; otherwise, the opening value of the target clutch pedal is decreased progressively according to a preset clutch release gradient value until the minimum limit value is 0%;
under the HCR _ creating state, the method is similar to the HCD _ creating state, and the difference is that the target vehicle speed and the current vehicle speed are changed into the condition that the target vehicle speed is larger than the current vehicle speed (the vehicle speed is a negative value during backing up);
with respect to the preset clutch release gradient value:
in order to improve the clutch release efficiency, it is necessary to calibrate the clutch engagement point and disengagement point, and to adopt a slow disengagement (smaller gradient value) when the by-wire clutch pedal opening is in a region between the engagement point and disengagement point, and a fast disengagement (larger gradient value) when the by-wire clutch pedal opening is in a region other than the engagement point and disengagement point.
In addition, according to different specific working conditions, the slow separation gradient value and the fast separation gradient value under different working modes of the wire-controlled chassis system are different, and the preset clutch release gradient MAP under each state is not shared and can be calibrated independently;
line control gear selection control
Gear selection is carried out in the gear shifting process until loading is carried out (under the states of MD _ SEG-MD _ Load, HCD _ SEG-HCD _ creating, DS _ SEG-DS _ Load, BDS _ SEG-BDS _ Load and HCR _ SEG-HCR _ creating), and the corresponding target position of the gear selection motor is calculated according to the target gear position transmitted by the gear management module; calculating the target position of the gear selection motor according to N gear under the state of resetting neutral gear (MD _ Restore, HCD _ Restore, DS _ Restore, SPB _ Restore, BDS _ Restore, PP _ Restore and HCR _ Restore); maintaining the position of the previous target gear selecting motor in other states;
enabling conditions of the gear selecting motor:
the method comprises the following steps that 1 of the following 2 conditions is met, and the position of a gear selecting motor enabling mark is 1;
1) Selecting gears in the gear shifting process until loading (under the states of MD _ SEG-MD _ Load, HCD _ SEG-HCD _ creating, DS _ SEG-DS _ Load, BDS _ SEG-BDS _ Load and HCR _ SEG-HCR _ creating);
2) Reset neutral (MD _ reserve, HCD _ reserve, DS _ reserve, SPB _ reserve, BDS _ reserve, PP _ reserve, HCR _ reserve) state, and the shift motor position has been located at the N range corresponding position for 100ms.
Shift-by-wire control
Resetting neutral gear (MD _ Restore, HCD _ Restore, DS _ Restore, SPB _ Restore, BDS _ Restore, PP _ Restore and HCR _ Restore) state, or when the target gear position transmitted by the gear management module is N gear, the target position of the gear shifting motor is N gear position; when the target gear positions transmitted by the gear management module are 1, 3 and 5 gears, the target position of the gear shifting motor is a 3-gear position; when the target gear position transmitted by the gear management module is 2, 4, 6 or R gear, the target position of the gear shifting motor is 4 gear position;
the enabling conditions of the gear shifting motor are as follows:
the method comprises the following steps that 1, the enabling mark position 1 of a gear shifting motor meets the following 2 conditions;
1) Reset neutral (MD _ Restore, HCD _ Restore, DS _ Restore, SPB _ Restore, BDS _ Restore, PP _ Restore, HCR _ Restore) state;
2) And shifting until loading (under the states of MD _ SHG-MD _ Load, HCD _ SHG-HCD _ creating, DS _ SHG-DS _ Load, BDS _ SHG-BDS _ Load and HCR _ SHG-HCR _ creating) in the shifting process.
The preferred embodiments of the invention disclosed above are intended to be illustrative only. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best understand the invention for and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.
Claims (10)
1. A drive-by-wire chassis system for unmanned driving, comprising:
a steer-by-wire subsystem comprising a steer-by-wire module and a turn angle sensor for a steering wheel;
the brake-by-wire subsystem comprises a brake-by-wire module, an angle sensor and a brake switch;
the drive-by-wire clutch subsystem comprises a drive-by-wire clutch module and a clutch matching module;
a shift-by-wire subsystem comprising a shift-by-wire module, and a shift engagement module;
the system comprises a domain controller module, a control module and a control module, wherein the domain controller module comprises a drive-by-wire chassis domain controller and a drive-by-wire accelerator; the drive-by-wire chassis domain controller comprises a plurality of CAN communication interfaces, ADC interfaces for digital-to-analog conversion, DAC interfaces for analog-to-digital conversion, a plurality of GPIO input interfaces for collecting signals and a plurality of GPIO output interfaces for outputting signals.
2. The drive-by-wire chassis system for unmanned aerial vehicle of claim 1, wherein the clutch engagement module comprises a position sensor and a clutch switch or comprises a directional valve and a hydraulic line;
when a position sensor and a clutch switch are adopted, the wire control clutch module comprises a motor and a gear and drives a pressure rod to press a clutch pedal arm; the clutch switch adopts an original vehicle clutch switch;
when a reversing valve and a hydraulic pipeline are adopted, the wire control clutch module comprises a clutch master cylinder, an electric cylinder, a bracket, a linear bearing, a guide shaft, a limiting sleeve and a connecting seat; the clutch master cylinder adopts the clutch master cylinder with the same model or the same specification as the original vehicle, and the original vehicle clutch slave cylinder is switched to be driven by the clutch master cylinder of the line control clutch module through the reversing valve and the hydraulic pipeline.
3. The drive-by-wire chassis system for unmanned aerial vehicle of claim 1, wherein the shift mating module comprises a flexible shaft and a shift knob or consists of a cantilevered manipulator, a mounting bracket and a shift knob.
4. The drive-by-wire chassis system for unmanned aerial vehicle of claim 1, wherein the drive-by-wire chassis domain controller comprises a CAN communication interface for connecting an original vehicle CAN bus and for information interaction between nodes in the drive-by-wire chassis domain; the CAN communication interface connected with the original vehicle CAN bus is used for reading the rotating speed information fed back by the ECU and the vehicle speed information fed back by the ABS.
5. The drive-by-wire chassis system for unmanned aerial vehicle of claim 1, wherein the drive-by-wire chassis domain controller comprises 6-way ADC interfaces for acquiring sensor voltage signals of an electronic throttle, a brake-by-wire position sensor, and a clutch-by-wire position sensor, respectively.
6. The chassis-by-wire system for unmanned aerial vehicle of claim 1, wherein the chassis-by-wire domain controller comprises a 2-way DAC interface for outputting a throttle-by-wire analog voltage signal.
7. The drive-by-wire chassis system for unmanned aerial vehicle of claim 1, wherein the GPIO input interface is configured to collect a gear request signal, a driving mode switch signal, a brake switch signal, and a clutch switch status signal;
and the GPIO output interface is used for respectively outputting an ignition relay signal, a flameout relay signal, a parking relay signal, a state indicator lamp control signal and a gear mode state feedback signal.
8. A control method for a drive-by-wire chassis system for unmanned aerial vehicles, comprising the steps of:
s1, performing information interaction between application layer software and bottom layer software through a preset data interface, and transmitting information such as ADC (analog to digital converter) sampling data, CAN (controller area network) communication bus data, GPIO (general purpose input pin) states, bottom layer software zone bits and the like to an input module of the application layer software through the data interface by the bottom layer software;
the application layer software comprises an input module, a functional module and an output module; the functional modules comprise a fault diagnosis module, a fault processing module, a mode management module, a gear management module and a chassis control module;
the output module comprises a subsystem control parameter module, a CAN communication parameter module, a hardware output parameter module, a delay data module and a data interface module;
the bottom layer software also comprises a timer, a drive-by-wire subsystem control module and an equipment driving module;
s2, filtering analog quantity signals and digital quantity signals in the input module;
and S3, adding a debugging interface to the key data, and sending the key data into a data preprocessing submodule for data preprocessing.
9. The control method for the unmanned chassis-by-wire system according to claim 7, wherein the filtering process in step S2 comprises the steps of:
a1, performing low-pass filtering processing on 2-path accelerator pedal voltage signals;
a2, performing mean value filtering processing on the voltage signals of the line control moving position sensor 2;
a3, carrying out mean value filtering processing on the voltage signals of the line 2 clutch position control sensor;
and A4, performing mean value filtering processing on the power supply voltage signal.
10. The control method for the unmanned chassis by wire system according to claim 7, wherein the data preprocessing in the step S3 comprises the steps of:
a) Calculating the speed and the acceleration;
b) Calculating the brake-by-wire opening and the brake switch state;
c) Calculating the clutch opening and the clutch switch state of the drive-by-wire;
d) Calculating the current gear;
e) Calculating the working state of the engine;
f) Calculating a gear shifting state zone bit;
the method comprises the following steps of checking the reasonability of gears according to the instantaneous vehicle speed, and specifically comprises the following steps: if the current gear is in the 1 gear, the N gear or the R gear, directly outputting a check result of 0x1; the current gear is located in other gears, the corresponding engine rotating speed is calculated in a reverse pushing mode according to the instantaneous vehicle speed, the current gear speed ratio, the transmission system speed ratio and the wheel rolling radius, if the rotating speed is larger than 1000rpm, the verification is passed, the verification result flag bit =0x1 is output, and if the verification is not passed, the verification result flag bit =0x0 is output;
g) Calculating a target gear mode of a driver;
h) And (5) filtering the corner of the target steering wheel.
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2022
- 2022-10-14 CN CN202211261044.0A patent/CN115923835A/en active Pending
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Effective date of registration: 20240704 Address after: No. 99 Zhenxing Road, Economic Development Zone, Hanshan County, Ma'anshan City, Anhui Province, 238101 Applicant after: Anhui Xiaojun Intelligent Equipment Co.,Ltd. Country or region after: China Address before: Room 1056, No. 19, Tianzhi Road, Hefei Hi tech Development Zone, 230000 Anhui Province Applicant before: Hefei Zhixingtong Intelligent Technology Co.,Ltd. Country or region before: China |