CN110654456B

CN110654456B - Recirculating ball type steering safety redundancy system of unmanned commercial vehicle and control method

Info

Publication number: CN110654456B
Application number: CN201910990907.XA
Authority: CN
Inventors: 朱早贝; 张磊; 吕金桐
Original assignee: Beijing Yikong Zhijia Technology Co Ltd
Current assignee: Shanghai Yi'ao Technology Co ltd
Priority date: 2019-10-17
Filing date: 2019-10-17
Publication date: 2021-05-18
Anticipated expiration: 2039-10-17
Also published as: CN110654456A

Abstract

The utility model provides a pilotless commercial car recirculating ball formula turns to safe redundant system includes: an unmanned controller; an EPS controller electrically connected to the drone controller; the first oil pump device is connected to the oil storage tank and comprises a first driving device and a first oil pump connected with the first driving device; the second oil pump device is connected to the oil storage tank and comprises a second driving device and a second oil pump connected with the second driving device; the two-position three-way electric control electromagnetic valve is electrically connected to the EPS controller; the motor steering device comprises a first motor steering device and a second motor steering device which are respectively and electrically connected to the EPS controller and the unmanned controller and provide steering torque; the power executing mechanism comprises a circulating ball steering gear and an executing mechanism. Safety redundancy is increased from three aspects of a hydraulic power source, steering torque output and a steering controller, and powerful guarantee is provided for steering safety of the unmanned commercial vehicle.

Description

Recirculating ball type steering safety redundancy system of unmanned commercial vehicle and control method

Technical Field

The disclosure relates to the field of unmanned driving, in particular to a recirculating ball type steering safety redundancy system and a control method of an unmanned commercial vehicle.

Background

One of the centers of attention of the unmanned technology is safety performance, and in the case of an unmanned commercial vehicle, a steering system of the unmanned commercial vehicle is related to the safety performance of lateral control of the vehicle and belongs to one of the core safety subsystems. At present, a steering system of a commercial vehicle generally adopts an electric control hydraulic mode, a hydraulic system is controlled by an electric control unit so as to operate each steering actuating mechanism to realize the steering of the vehicle, the steering system mainly comprises a sensor, an electromagnetic control valve, an electric control unit, a hydraulic oil cylinder, a hydraulic oil pump and the like, and the integrated system is generally called as EHPS (electronic hydraulic Power steering).

With the development of the unmanned technology, the unmanned driving of the commercial vehicle is also more and more generally accepted as the scene that the unmanned technology first falls to the ground, and for an L4-level unmanned commercial vehicle which needs to realize an asil (automatic Safety Integration level) D Safety level (classified into A, B, C, D level, and the D level is the highest level), the Safety redundancy of a steering system of the commercial vehicle is a task which needs to be deeply considered and designed.

Disclosure of Invention

Technical problem to be solved

The present disclosure provides a recirculating ball type steering safety redundant system and a control method for an unmanned commercial vehicle to at least partially solve the above-mentioned technical problems.

(II) technical scheme

According to one aspect of the present disclosure, there is provided a recirculating ball steering safety redundant system for an unmanned commercial vehicle, comprising:

the unmanned controller is used for generating a control signal for controlling the vehicle to carry out unmanned driving;

the EPS controller is electrically connected to the unmanned controller and is used for controlling the motor steering device to output steering torque according to the control signal;

the first oil pump device is connected to the oil storage tank and comprises a first driving device and a first oil pump connected with the first driving device, wherein the first driving device is an engine or an oil pump motor;

the second oil pump device is connected to the oil storage tank and comprises a second driving device and a second oil pump connected with the second driving device, wherein the second driving device is an oil pump motor;

the two-position three-way electric control electromagnetic valve is electrically connected to the EPS controller, and the first oil pump and the second oil pump are respectively connected to the input of the two-position three-way electric control electromagnetic valve through the first one-way valve and the second one-way valve;

the motor steering device comprises a first motor steering device and a second motor steering device, wherein the first motor steering device is electrically connected to the EPS controller, the second motor steering device is electrically connected to the unmanned controller, and the output torque of the first motor steering device and the output torque of the second motor steering device can be coupled with the output of the hydraulic mechanism to provide steering torque;

the power executing mechanism comprises a circulating ball steering gear and an executing mechanism, wherein the circulating ball steering gear comprises a main circulating ball steering gear and an auxiliary circulating ball steering gear, an input shaft of the main circulating ball steering gear is connected with the output of the motor steering device, and the main circulating ball steering gear and the auxiliary circulating ball steering gear are connected through an oil way and are respectively connected to the executing mechanism.

In some embodiments, the recirculating ball type steering safety redundant system for the unmanned commercial vehicle further comprises:

the inlet of the three-way valve is connected with the oil storage tank, and the two outlets are respectively connected with the first oil pump and the second oil pump.

a first flow sensor connected between the first oil pump and the first check valve;

and the second flow sensor is connected between the second oil pump and the second one-way valve.

the first end of the steering connecting rod is connected with a steering wheel, the second end of the steering connecting rod is connected with an input shaft of a main circulating ball steering gear, and the first motor steering device and the second motor steering device are installed on the steering connecting rod in series;

and the steering pull rod is respectively connected between the main circulating ball steering gear, the auxiliary circulating ball steering gear and the wheels.

In some embodiments, the first motor steering device comprises:

the first torque motor is arranged on the steering connecting rod and connected with the EPS controller, and the rated output torque of the first torque motor can realize the steering of the vehicle;

the second motor steering device includes:

and the second torque motor is arranged on the steering connecting rod and connected with the unmanned controller, and the rated output torque of the second torque motor can realize the steering of the vehicle.

In some embodiments, the unmanned commercial vehicle recirculating ball steering safety redundant system further comprises:

and the torque sensor and the corner sensor are arranged on the steering connecting rod and are used for detecting the torque and the corner of the steering connecting rod.

According to another aspect of the present disclosure, there is provided a driverless commercial vehicle steering safety redundancy system, comprising:

the motor steering device comprises a first motor steering device, a second motor steering device and a third motor steering device, wherein the first motor steering device and the third motor steering device are electrically connected to the EPS controller, and the second motor steering device is electrically connected to the unmanned controller and used for providing steering torque;

the power executing mechanism comprises a first gear and rack steering gear, a second gear and rack steering gear and an executing mechanism, wherein the output of the first motor steering device and the output of the second motor steering device are connected to the executing mechanism through the first gear and rack steering gear, and the output of the third motor steering device is connected to the executing mechanism through the second gear and rack steering gear.

According to another aspect of the present disclosure, there is provided a control method of the recirculating ball steering redundancy system for unmanned commercial vehicles as described above, comprising:

s100, starting a recirculating ball type steering safety redundancy system of the unmanned commercial vehicle;

s200, judging the states of the EPS controller, the VCU, the first oil pump device, the second oil pump device and the two-dimensional three-way electromagnetic valve; if the fault exists, selecting a corresponding control strategy according to different fault states;

and S300, controlling the vehicle to steer according to the control strategy.

In some embodiments, the step S200 includes:

if the first oil pump device fails, the EPS controller, the VCU, the second oil pump device and the two-position three-way electromagnetic valve are normal, a hydraulic power source redundancy selection is provided, the second oil pump device is started to provide hydraulic pressure for a steering system, and torque is output.

In some embodiments, the providing hydraulic power source redundancy options comprises:

the platform or the planning layer sends an expected track path of the vehicle;

the unmanned controller calculates and obtains the turning angle and the required steering speed of the current vehicle through the expected track path of the vehicle, and sends the turning angle and the required steering speed to the EPS controller through the VCU; meanwhile, the unmanned controller controls the start of the second oil pump device;

the EPS controller controls the first steering motor device to output steering torque, hydraulic oil flows into the circulating ball to generate hydraulic steering torque, and the hydraulic steering torque is coupled with the motor torque and then output to push the steering pull rod to achieve wheel steering.

In some embodiments, the step S200 further includes:

if the first oil pump device and the second oil pump device are both in failure or the two-position three-way electromagnetic valve is in failure, the EPS controller and the VCU are normal, the redundant selection of the steering torque output is provided, and the steering torque is output through the second motor steering device.

In some embodiments, the providing a steering torque output redundancy option comprises:

the platform or the planning layer sends an expected track path of the vehicle;

the ADCU controller calculates and obtains the turning angle and the required steering speed of the current vehicle through the expected track path of the vehicle, and sends the turning angle and the required steering speed to the EPS controller through the VCU;

the EPS controller controls the first steering motor device to output a main steering torque, meanwhile, the ADCU controls the second steering motor device to output a power-assisted steering torque, the main steering torque and the power-assisted steering torque are coupled and then output to an input shaft of the recirculating ball steering gear, and the recirculating ball steering gear pushes a steering pull rod to achieve wheel steering.

In some embodiments, the step S200 further includes:

if the EPS controller or the VCU has a fault, the unmanned controller is directly started and controls the second motor steering device to output steering torque.

In some embodiments, the method comprises:

the platform or the planning layer sends an expected track path of the vehicle;

the unmanned controller calculates and obtains the turning angle and the required steering speed of the current vehicle through the expected track path of the vehicle;

judging whether the EPS controller or the VCU is disconnected or invalid, if any one of the EPS controller and the VCU is disconnected or invalid, starting the unmanned controller and controlling the second motor steering device to output steering torque to the recirculating ball steering gear to realize vehicle steering; if both are not disconnected or invalid, the next step is carried out;

the unmanned controller sends the turning angle and the required steering speed of the current vehicle to the EPS controller through the VCU; the EPS controller controls the first motor steering device to output steering torque to the input shaft of the recirculating ball steering gear, and steering of the vehicle is achieved.

According to another aspect of the present disclosure, there is provided a recirculating ball steering safety redundant system for an unmanned commercial vehicle or a steering safety redundant system for an unmanned commercial vehicle as described above.

(III) advantageous effects

According to the technical scheme, the recirculating ball type steering safety redundancy system and the control method of the unmanned commercial vehicle have at least one of the following beneficial effects:

(1) by adding the motor oil pump device on the basis of the engine oil pump device, when the system of the engine oil pump device fails, the hydraulic supply of a steering system can be ensured through the motor oil pump device, and the safety redundancy of a hydraulic power source of the steering system is increased;

(2) by adding the motor steering device on the steering connecting rod, when the hydraulic steering system fails, the motor steering device can be switched to control steering in time, so that the steering capacity of a vehicle when the hydraulic steering system fails is ensured, and the safety redundancy of the steering torque output of the steering system is increased;

(3) the installed second motor steering device can also directly control steering through the unmanned controller under extreme working conditions of EPS or VCU control failure and the like, so that the steering performance of a vehicle is ensured, and the safety redundancy of steering control of a steering system is increased;

(4) according to the method and the device, safety redundancy is increased from the core parts of three steering control of the hydraulic power source, the steering torque output and the steering controller on the basis of the traditional steering system, so that the safety redundancy of the system is greatly improved, more powerful guarantee is provided for the steering safety of the unmanned commercial vehicle, the steering capacity of the vehicle can be still ensured under various extreme working conditions, and the safety performance of the unmanned commercial vehicle is improved.

Drawings

Fig. 1 is a schematic structural diagram of a recirculating ball type steering safety redundancy system of an unmanned commercial vehicle according to an embodiment of the disclosure.

Fig. 2 is a flowchart of a control method of the recirculating ball type steering safety redundant system of the unmanned commercial vehicle according to the embodiment of the disclosure.

Fig. 3a, 3b, and 3c are control strategies corresponding to the control method of this embodiment under three different fault states.

Fig. 4 is a flowchart of a conventional steer-by-wire control method.

Fig. 5 is a flowchart of a method for controlling the working steering of an electric motor oil pump according to an embodiment of the present disclosure.

Fig. 6 is a flowchart of a steering control method of a motor steering apparatus according to an embodiment of the present disclosure.

Fig. 7 is a flowchart of an EPS/VCU offline/failed steering control method according to an embodiment of the present disclosure.

Fig. 8 is a schematic structural diagram of a recirculating ball type steering safety redundancy system of an unmanned commercial vehicle according to an embodiment of the disclosure.

Fig. 9 is a schematic structural diagram of a steering safety redundancy system of an unmanned commercial vehicle according to an embodiment of the present disclosure.

[ description of main reference numerals in the drawings ] of the embodiments of the present disclosure

1. An ADCU controller; 2. EPS controller

3. Engine oil pump device

301. An engine; 302. first oil pump

4. Oil pump device of motor

401. An oil pump motor; 402. second oil pump

3' first motor oil pump device

301' first oil pump motor

4' second motor oil pump device

401', a second oil pump motor

5. An oil storage tank; 6. three-way valve

7. A first flow sensor; 8. second flow sensor

9. A first check valve; 10. second check valve

11. A two-position three-way electric control electromagnetic valve; 12. third check valve

13. A main recirculating ball diverter; 14. auxiliary circulating ball steering gear

15. A steering wheel; 16. wheel of vehicle

17. Second motor steering device

1701. Second torque motor

18. First motor steering device

1801. First torque motor

19. A steering link; 20. steering cross bar

21. A steering tie rod; 22. torque sensor

23. A rotation angle sensor; 24. third motor steering device

25. A first rack and pinion; 26. A second rack and pinion diverter.

Detailed Description

The invention provides a recirculating ball type steering safety redundancy system of an unmanned commercial vehicle, wherein a recirculating ball type steering gear needs hydraulic input for assisting power due to the structure of the recirculating ball type steering gear, and the safety redundancy of the steering system cannot be increased from the hydraulic system only by modifying the structure of the recirculating ball; the safety of a power supply of a steering system is prevented by adding a high-voltage low-voltage dual power supply in the prior art, but the high-voltage power supply generally only exists on a new energy vehicle, and for a traditional commercial vehicle, only a low-voltage power supply is used, and how to maximize the safety redundancy of the steering system on the basis of only the low-voltage power supply is also considered from other aspects.

For the purpose of promoting a better understanding of the objects, aspects and advantages of the present disclosure, reference is made to the following detailed description taken in conjunction with the accompanying drawings.

Certain embodiments of the present disclosure will now be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the disclosure are shown. Indeed, various embodiments of the disclosure may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements.

In one exemplary embodiment of the present disclosure, a recirculating ball steering safety redundant system for an unmanned commercial vehicle is provided. The working principle of the traditional circulating ball type steering system of the unmanned commercial vehicle is as follows: an unmanned controller, such as an adcu (automatic Driving Control unit) controller outputs a target rotation angle, and an eps (electronic Power steering) controller receives the target rotation angle, and then controls a first torque motor in a first motor steering device to output a steering torque, a steering wheel rotates to drive a steering connecting rod to Control a Control valve in a recirculating ball type steering gear, hydraulic oil flows into a main recirculating ball type steering gear and a secondary recirculating ball type steering gear to generate hydraulic steering Power-assisted torque to be coupled with the motor torque, and the recirculating ball type steering gear outputs the steering torque, so that a steering pull rod mechanism is pushed to achieve steering of wheels. The main circulating ball and the auxiliary circulating ball are connected through an oil way, and a hydraulic steering control valve is embedded in the main circulating ball and is controlled by a steering connecting rod of a steering wheel. The engine is used for driving the oil pump to work, and power is provided for the hydraulic system.

Fig. 1 is a schematic structural diagram of a recirculating ball type steering safety redundancy system of an unmanned commercial vehicle according to an embodiment of the disclosure. As shown in fig. 1, the recirculating ball type steering safety redundant system of the unmanned commercial vehicle mainly comprises an ADCU controller 1, an EPS controller 2, an engine oil pump device 3, a motor oil pump device 4, a two-position three-way electric control solenoid valve 11, a first motor steering device 18, a second motor steering device, a main recirculating ball steering gear 13, an auxiliary recirculating ball steering gear 14 and the like.

Compared with the traditional circulating ball type steering system of the unmanned commercial vehicle, the steering safety redundant system of the embodiment is additionally provided with the motor oil pump device 4, the two-position three-way electric control electromagnetic valve 11 and the second motor steering device 17. The motor oil pump device 4 and the engine oil pump device 3 are installed in parallel, and are gathered through the two-position three-way electromagnetic valve 11, so that hydraulic power can be provided for a steering system at the same time. First motor steering gear 18 and second motor steering gear 17 are installed on steering connecting rod 19 in series, and steering connecting rod 19 lug connection recirculating ball steering gear input shaft through above-mentioned structure, controls through certain tactics simultaneously to promote unmanned commercial vehicle steering system's safety redundancy, the maximize guarantees unmanned steering system's reliability and security.

Specifically, referring to fig. 1, the oil path of the steering safety redundant system of the present embodiment includes: the oil tank 5 is connected to the engine oil pump device 3 and the motor oil pump device 4 by a three-way valve 6. The engine oil pump device 3 comprises an engine 301 and a first oil pump 302 connected with the engine; motor oil pump unit 4 includes oil pump motor 401 and the second oil pump 402 that links to each other, three-way valve entry linkage oil storage tank 5, and first oil pump 302 and second oil pump 402 are connected respectively to two exports, first oil pump 302 connects gradually first flow sensor 7 and first check valve 9, second oil pump 402 connects gradually second flow sensor 8 and second check valve 10. The first one-way valve 9 and the second one-way valve 10 are connected with a two-position three-way electric control electromagnetic valve 11, the two-position three-way electric control electromagnetic valve 11 is connected with a main circulating ball steering gear 13, the main circulating ball steering gear 13 is connected with an auxiliary circulating ball steering gear 14 through an oil way, and a hydraulic steering control valve is embedded in the main circulating ball steering gear 13 and is controlled by a steering connecting rod 19. Hydraulic oil flows into the main circulating ball steering gear and the auxiliary circulating ball steering gear to generate hydraulic steering power-assisted torque which is coupled with motor torque, and the main circulating ball steering gear 13 and the auxiliary circulating ball steering gear 14 output steering torque so as to push the steering pull rod 21 to realize the steering of wheels. The third check valve 12 is connected between the oil tank 5 and the hydraulic mechanism, and forms a one-way oil return passage from the hydraulic mechanism to the oil tank 5.

By adding the motor oil pump device on the basis of the engine oil pump device, when the system of the engine oil pump device fails, the hydraulic supply of a steering system can be ensured through the motor oil pump device, and the safety redundancy of a hydraulic power source of the steering system is improved.

Referring to fig. 1 again, the control path of the steering safety redundancy system of the present embodiment includes: the ADCU controller 1 is connected to the oil pump motor 401 and the EPS controller 2, the ADCU controller 1 is connected to the second torque motor 1701 of the motor steering device 17, the EPS controller 2 is connected to the first torque motor 1801 of the first motor steering device 18, and rated output torques of the first torque motor 1801 and the second torque motor 1701 enable vehicle steering. Meanwhile, the EPS controller 1 is also connected to a two-position three-way electrically controlled solenoid valve 11 and an electromagnetic control valve 13. The ADCU controller 1 is also connected to a torque sensor 22 and a rotation angle sensor 23. The torque sensor 22 and the rotation angle sensor 23 are mounted on the steering link 19. One end of the steering connecting rod 19 is connected with the steering wheel 15, the other end of the steering connecting rod is connected with an input shaft of the main circulating ball steering gear 13, the output of the main circulating ball steering gear 13 is connected with a steering pull rod 21, and the steering pull rod 21 is connected with the wheels 16 to control the steering of the wheels.

The motor steering device is arranged on the steering connecting rod, when an engine or a motor oil pump fails, the motor steering device can be switched to in time to Control steering, the steering capacity of a Vehicle when a circulating ball type steering system fails is ensured, the safety redundancy of steering torque output of the steering system is increased, and the steering can be directly controlled through the ADCU under the extreme working conditions of failure Control of an EPS (electric power steering) or a Vehicle Control Unit (VCU), so that the steering performance of the Vehicle is ensured.

The steering safety redundancy system of the embodiment is connected in the mode of the figure 1, and is controlled by a certain strategy, so that the safety redundancy of the steering system of the unmanned commercial vehicle is improved, and the reliability and the safety of the unmanned steering system are guaranteed to the maximum extent.

According to the circulating ball type steering safety redundancy system of the unmanned commercial vehicle, on the basis of a traditional steering system, safety redundancy is increased from the core parts of three steering controls of a hydraulic power source, steering torque output and a steering controller, so that the safety redundancy of the system is greatly improved, and more powerful guarantee is provided for the steering safety of the unmanned commercial vehicle.

In a second embodiment of the disclosure, a control method of a recirculating ball type steering safety redundant system of an unmanned commercial vehicle is provided. Fig. 2 is a flowchart of a control method of the recirculating ball type steering safety redundant system of the unmanned commercial vehicle according to the embodiment of the disclosure. As shown in fig. 2, the control method of the recirculating ball type steering safety redundant system of the unmanned commercial vehicle disclosed by the invention comprises the following steps:

s200, judging the states of the EPS controller, the vehicle control unit, the engine oil pump device, the motor oil pump device and the two-dimensional three-way electromagnetic valve; if the fault exists, selecting a corresponding control strategy according to different fault states;

and S300, controlling the vehicle to steer according to the control strategy.

In the step S200, if it is determined that the EPS controller, the vehicle controller, the engine oil pump device, the motor oil pump device, and the two-dimensional three-way solenoid valve are all normal, the engine oil pump device is used to output torque; and if the component has a fault, processing by adopting a corresponding control strategy. In this embodiment, the different fault states in step S200 include three situations. Fig. 3a, 3b, and 3c show the corresponding control strategies in three different fault states according to this embodiment.

In a first failure state S201, as shown in fig. 3a, if the engine oil pump device fails, and the EPS controller, the VCU, the motor oil pump device, and the two-position three-way solenoid valve are normal, a hydraulic power source redundancy selection is provided to the safety redundancy system, and the motor oil pump device is started to provide hydraulic pressure to the steering system to output torque.

Preferably, if the EPS controller, the VCU, the engine oil pump device, the motor oil pump device and the two-position three-way electromagnetic valve are all normal, the engine oil pump can be used for main oil supply, and the motor oil pump is used for participating in oil supply under specific conditions, so that energy consumption is reduced.

Fig. 4 is a schematic flow chart of a conventional steer-by-wire control. As shown in fig. 4, the ADCU controller calculates the turning angle of the vehicle and the required steering speed through a trajectory path sent by the platform or the decision layer, and sends the turning angle and the required steering speed to the EPS controller through the VCU, the EPS controller controls the first steering motor device to output the steering torque, the steering wheel rotates to drive the connecting rod to control the hydraulic control valve, the hydraulic oil flows into the circulating ball to generate the hydraulic steering torque, and the hydraulic steering torque is coupled with the motor torque and then output to push the steering pull rod to steer the wheel. As can be seen from this flow, once the engine oil pump device fails, or the engine is unable to provide power to the oil pump, the entire steering system will lose power and lose automatic steering capability, creating a hazard.

In this embodiment, as shown in fig. 3a, after the steering control is started, the ADCU may monitor the state of the sending oil pump system in real time, and when it is detected that the sending engine is turned off, the sending engine fails to output power, or the engine oil pump fails, the ADCU will control to start the electric oil pump device to provide hydraulic power to the steering system, where a working flow chart of the steering system is shown in fig. 5, and includes:

s2011, the platform or the planning layer sends an expected track path of the vehicle;

s2012, the ADCU controller calculates and obtains the turning angle and the required steering speed of the current vehicle through the expected track path of the vehicle, and sends the turning angle and the required steering speed to the EPS controller through the VCU; meanwhile, the ADCU controls the starting of the electric oil pump device;

and S2013, the EPS controller controls the first steering motor device to output steering torque, hydraulic steering torque is generated when hydraulic oil flows into the circulating ball, and the hydraulic steering torque is coupled with motor torque and then output to push the steering pull rod to achieve wheel steering.

Preferably, the process further comprises:

and S2014, after the vehicle is steered, feeding back the steering angle signal to the EPS controller, and returning to the step S2013.

In the control method of the embodiment, when the engine oil pump device system fails, the motor oil pump device is adopted to ensure the hydraulic supply of the steering system, so that the safety redundancy of the hydraulic power source of the steering system is increased.

In a second failure state S202, as shown in fig. 3b, if both the engine oil pump device and the motor oil pump device fail, or the two-position three-way solenoid valve fails, and the EPS controller and the VCU are normal, a redundant selection of the output of the steering torque is provided, and the steering torque is output through the motor steering device.

Referring to fig. 1 again, in the steering process of the unmanned vehicle, the EPS controller controls the steering control valve by controlling the two-position three-way solenoid valve and the steering wheel to rotate, and hydraulic oil flows into the recirculating ball steering gear to generate hydraulic steering torque. As can be seen from fig. 1, although the system adds the electric motor oil pump to add redundancy to the hydraulic power source, once both the engine and the electric motor oil pump fail, or the two-position three-way solenoid valve fails (e.g., is jammed) or the steering control valve is jammed and fails, the system cannot provide hydraulic steering torque.

In order to solve the problem, a second motor steering device is added, is arranged on a steering connecting rod, is connected with the first motor steering device on an input shaft of the recirculating ball steering gear in series through the steering connecting rod, is directly controlled by an ADCU controller and can directly output steering torque. In this case, the ADCU will directly activate the second motor steering device to provide the power steering torque.

Fig. 6 is a flowchart of the steering control of the motor steering apparatus according to the present embodiment. As shown in fig. 6, the workflow of the steering system of the method includes:

s2021, the platform or the planning layer sends an expected track path of the vehicle;

s2022, calculating by the ADCU controller through an expected track path of the vehicle to obtain a turning angle and a required steering speed of the current vehicle, and sending the turning angle and the required steering speed to the EPS controller through the VCU;

s2023, the EPS controller controls the first steering motor device to output a main steering torque, meanwhile, the ADCU controls the second steering motor device to output a power-assisted steering torque, the main steering torque and the power-assisted steering torque are coupled and then output to an input shaft of the recirculating ball steering gear, and the recirculating ball steering gear pushes a steering pull rod to achieve wheel steering.

Preferably, the process further comprises:

s2024, after the vehicle is steered, the steering angle signal is fed back to the EPS controller, and the process returns to step S2023.

By the control method, when the engine and the motor oil pump fail, the pure electric steering device can be switched to control steering in time, the steering capacity of the vehicle when the hydraulic steering system fails is ensured, and the safety redundancy of the steering torque output of the steering system is increased.

A third failure state S203 is shown in fig. 3c, where if the EPS controller or VCU fails, the ADCU directly starts and controls the second motor steering, outputting a steering torque.

In the actual driving process of the conventional vehicle, if the EPS communication is disconnected or the EPS fails suddenly due to a serious fault, since the EPS is the only controller for controlling steering, in this case, if the VCU has a relevant diagnosis function, the VCU may directly control to exit the unmanned control state and perform emergency braking for parking. However, at this time, due to the failure or disconnection of the EPS, the vehicle completely loses the steering ability, and if the vehicle is braked suddenly and the steering wheel angle is not 0, the vehicle is likely to drift or roll over, so that danger is caused; or because the VCU is disconnected or disabled, the steering control command sent by the ADCU needs to be sent to the EPS control through the VCU, and at this time, the EPS cannot receive the steering control command, and the vehicle also loses the steering capability and is in danger.

When the above-mentioned condition takes place, the ADCU will directly start and control the electronic device that turns to of second, because the motor has corresponding fast, sensitivity is high, characteristics that control accuracy is high, can insert fast and turn to, guarantee the steering ability of vehicle, avoid dangerous emergence under this kind of extreme operating mode. The work flow of the steering system at this time is shown in fig. 7, and includes:

s2031, the platform or the planning layer sends an expected track path of the vehicle;

s2032, the ADCU controller calculates and obtains the turning angle and the required steering speed of the current vehicle through the expected track path of the vehicle;

s2033, judging whether the EPS controller or the VCU is disconnected or invalid, if the EPS controller or the VCU is not disconnected or invalid, turning to S2034; if either one of the two is disconnected or failed, go to step S2035:

s2034, the ADCU controller sends the turning angle of the current vehicle and the required steering speed to the EPS controller through the VCU; the EPS controller controls the first motor steering device to output steering torque to an input shaft of the recirculating ball steering gear to realize steering of the vehicle;

s2035, the ADCU starts and controls the second motor steering device to output steering torque to the input shaft of the recirculating ball steering gear, so as to realize vehicle steering.

Preferably, the process further comprises:

s2036, after the vehicle is steered, the steering angle signal is fed back to the EPS controller, and the process returns to step S2034.

By the method, steering can be directly controlled through the ADCU under extreme working conditions such as EPS or VCU control failure, so that the steering performance of a vehicle is ensured, and the safety redundancy of steering control of a steering system is increased.

For the purpose of brief description, any technical features that can be applied to the same in the above embodiment 1 are described herein, and the same description need not be repeated.

In a third embodiment of the disclosure, a recirculating ball type steering safety redundant system for an unmanned commercial vehicle is also provided. The commercial vehicle is a hybrid power or pure electric vehicle.

Fig. 8 is a schematic structural diagram of a recirculating ball type steering safety redundancy system of an unmanned commercial vehicle according to an embodiment of the disclosure. As shown in fig. 8, the recirculating ball type steering safety redundant system of the unmanned commercial vehicle mainly comprises an ADCU controller 1, an EPS controller 2, a first motor oil pump device 3 ', a second motor oil pump device 4', a two-position three-way electric control solenoid valve 11, a first motor steering device 18, a second motor steering device 17, a main recirculating ball steering gear 13, an auxiliary recirculating ball steering gear 14 and the like. The first motor oil pump device 3 'includes a first oil pump motor 301' and a first oil pump 302, and the second motor oil pump device 4 'includes a second oil pump motor 401' and a second oil pump 402.

Different from the first embodiment, the power source of the hydraulic system adopts a full-electric scheme, and an engine is not used any more, so that the oil consumption of the engine can be further reduced, and the problem that the safety redundancy purpose of the double power sources is lost due to the working condition that the engine only can supply power by a motor oil pump when the engine is not started (for example, the pure electric driving working condition of a hybrid vehicle) in some working conditions can also be avoided. Meanwhile, for a pure electric vehicle, as the engine does not work, the safety redundancy of a steering system is realized by replacing the engine with the motor.

For the purpose of brief description, any technical features of the first embodiment that can be applied to the same are described herein, and the same description is not repeated.

It can be understood that the control method of the system in this embodiment is similar to the control method of the recirculating ball type steering safety redundant system of the unmanned commercial vehicle in the second embodiment, and the detailed description is omitted here.

In a fourth embodiment of the present disclosure, a steering safety redundancy system for an unmanned commercial vehicle is further provided. The commercial vehicle is a hybrid power or pure electric vehicle.

Fig. 9 is a schematic structural diagram of a steering safety redundancy system of an unmanned commercial vehicle according to an embodiment of the present disclosure. As shown in fig. 9, the steering safety redundancy system of the unmanned commercial vehicle of the present disclosure mainly includes an ADCU controller 1, an EPS controller 2, a first motor steering device 18, a second motor steering device 17, a third motor steering device 24, a first rack-and-pinion steering device 25, a second rack-and-pinion steering device 26, and the like.

Different from the first and third embodiments, the steering safety redundant system of the unmanned commercial vehicle does not comprise a hydraulic system, the whole steering system is changed into a full electric control system, the hydraulic power-assisted system is optimized into a third motor steering device 24 at the moment, and the steering device controlled by the EPS and the recirculating ball steering device can be directly optimized into a steering device with a gear rack and is arranged on the steering cross rod 20 to directly act on the vehicle.

Specifically, in this embodiment, the ADCU controller is connected to the second motor steering device 17 and the EPS controller has two outputs, one connected to the first motor steering device 18 and the other connected to the third motor steering device 24. The first motor steering device 18 and the second motor steering device 17 are connected to a steering connecting rod 19 in series, the steering connecting rod 19 is connected to a steering cross rod 20 through a first rack-and-pinion steering gear 25, two ends of the steering cross rod 20 are connected with wheels 16, steering torque output by the first motor steering device 18 and the second motor steering device 17 is coupled and then acts on the steering connecting rod 19, and is transmitted to the steering cross rod 20 through the first rack-and-pinion steering gear 25 by the steering connecting rod 19 to steer the wheels; the output of the third motor steering device 24 is connected to the steering crossbar 20 through a second rack and pinion steering gear 26 so that the steering torque output by the third motor steering device 24 is used to steer the wheels.

The system scheme of the embodiment can be used for the conventional hybrid power, pure electric and hydraulic system-free commercial vehicles, can basically contain most commercial vehicle types, and greatly widens the applicability of the safety redundancy system. Any technical features that can be applied to the same embodiment are described herein, and the same description need not be repeated.

So far, the embodiments of the present disclosure have been described in detail with reference to the accompanying drawings. It is to be noted that, in the attached drawings or in the description, the implementation modes not shown or described are all the modes known by the ordinary skilled person in the field of technology, and are not described in detail. Further, the above definitions of the various elements and methods are not limited to the various specific structures, shapes or arrangements of parts mentioned in the examples, which may be easily modified or substituted by those of ordinary skill in the art.

It should also be noted that directional terms, such as "upper", "lower", "front", "rear", "left", "right", and the like, used in the embodiments are only directions referring to the drawings, and are not intended to limit the scope of the present disclosure. Throughout the drawings, like elements are represented by like or similar reference numerals. Conventional structures or constructions will be omitted when they may obscure the understanding of the present disclosure.

And the shapes and sizes of the respective components in the drawings do not reflect actual sizes and proportions, but merely illustrate the contents of the embodiments of the present disclosure. Furthermore, in the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

Unless otherwise indicated, the numerical parameters set forth in the specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by the present disclosure. In particular, all numbers expressing quantities of ingredients, reaction conditions, and so forth used in the specification and claims are to be understood as being modified in all instances by the term "about". Generally, the expression is meant to encompass variations of ± 10% in some embodiments, 5% in some embodiments, 1% in some embodiments, 0.5% in some embodiments by the specified amount.

Furthermore, the word "comprising" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

The use of ordinal numbers such as "first," "second," "third," etc., in the specification and claims to modify a corresponding element does not by itself connote any ordinal number of the element or any ordering of one element from another or the order of manufacture, and the use of the ordinal numbers is only used to distinguish one element having a certain name from another element having a same name.

In addition, unless steps are specifically described or must occur in sequence, the order of the steps is not limited to that listed above and may be changed or rearranged as desired by the desired design. The embodiments described above may be mixed and matched with each other or with other embodiments based on design and reliability considerations, i.e., technical features in different embodiments may be freely combined to form further embodiments.

The algorithms and displays presented herein are not inherently related to any particular computer, virtual machine, or other apparatus. Various general purpose systems may also be used with the teachings herein. The required structure for constructing such a system will be apparent from the description above. Moreover, this disclosure is not directed to any particular programming language. It is appreciated that a variety of programming languages may be used to implement the present disclosure as described herein, and any descriptions above of specific languages are provided for disclosure of enablement and best mode of the present disclosure.

The disclosure may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. Various component embodiments of the disclosure may be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. Those skilled in the art will appreciate that a microprocessor or Digital Signal Processor (DSP) may be used in practice to implement some or all of the functionality of some or all of the components in the relevant apparatus according to embodiments of the present disclosure. The present disclosure may also be embodied as apparatus or device programs (e.g., computer programs and computer program products) for performing a portion or all of the methods described herein. Such programs implementing the present disclosure may be stored on a computer-readable medium or may be in the form of one or more signals. Such a signal may be downloaded from an internet website or provided on a carrier signal or in any other form.

Those skilled in the art will appreciate that the modules in the device in an embodiment may be adaptively changed and disposed in one or more devices different from the embodiment. The modules or units or components of the embodiments may be combined into one module or unit or component, and furthermore they may be divided into a plurality of sub-modules or sub-units or sub-components. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and all of the processes or elements of any method or apparatus so disclosed, may be combined in any combination, except combinations where at least some of such features and/or processes or elements are mutually exclusive. Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Also in the unit claims enumerating several means, several of these means may be embodied by one and the same item of hardware.

Similarly, it should be appreciated that in the foregoing description of exemplary embodiments of the disclosure, various features of the disclosure are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various disclosed aspects. However, the disclosed method should not be interpreted as reflecting an intention that: that is, the claimed disclosure requires more features than are expressly recited in each claim. Rather, as the following claims reflect, disclosed aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this disclosure.

The above-mentioned embodiments are intended to illustrate the objects, aspects and advantages of the present disclosure in further detail, and it should be understood that the above-mentioned embodiments are only illustrative of the present disclosure and are not intended to limit the present disclosure, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present disclosure should be included in the scope of the present disclosure.

Claims

1. A recirculating ball type steering safety redundancy system for an unmanned commercial vehicle, comprising:

the EPS controller (2) is electrically connected to the unmanned controller and is used for controlling the motor steering device to output steering torque according to the control signal;

the first oil pump device is connected to the oil storage tank (5) and comprises a first driving device and a first oil pump (302) connected with the first driving device, wherein the first driving device is an engine (301) or an oil pump motor;

the second oil pump device is connected to the oil storage tank (5) and comprises a second driving device and a second oil pump (402) connected with the second driving device, wherein the second driving device is an oil pump motor;

the two-position three-way electric control electromagnetic valve (11) is electrically connected to the EPS controller (2), and the first oil pump (302) and the second oil pump (402) are respectively connected to the input of the two-position three-way electric control electromagnetic valve (11) through a first one-way valve (9) and a second one-way valve (10);

the motor steering device comprises a first motor steering device (18) and a second motor steering device (17), wherein the first motor steering device (18) is electrically connected to the EPS controller (2), the second motor steering device (17) is electrically connected to the unmanned controller, and the output torque of the first motor steering device (18) and the output torque of the second motor steering device (17) can be output-coupled with the hydraulic mechanism to provide steering torque;

the power executing mechanism comprises a circulating ball steering gear and an executing mechanism, wherein the circulating ball steering gear comprises a main circulating ball steering gear (13) and an auxiliary circulating ball steering gear (14), an input shaft of the main circulating ball steering gear (13) is connected with the output of the motor steering device, and the main circulating ball steering gear (13) is connected with the auxiliary circulating ball steering gear (14) through an oil way and is respectively connected to the executing mechanism.

2. The unmanned commercial vehicle recirculating ball steering redundant safety system of claim 1, further comprising:

the inlet of the three-way valve (6) is connected with the oil storage tank (5), and the two outlets are respectively connected with the first oil pump (302) and the second oil pump (402).

3. The unmanned commercial vehicle recirculating ball steering redundant safety system of claim 1, further comprising:

a first flow sensor (7) connected between the first oil pump (302) and the first check valve (9);

a second flow sensor (8) connected between the second oil pump (402) and the second check valve (10).

4. The unmanned commercial vehicle recirculating ball steering redundant safety system of claim 1, further comprising:

the first end of the steering connecting rod (19) is connected with the steering wheel (15), the second end of the steering connecting rod (19) is connected with the input shaft of the main circulating ball steering gear (13), and the first motor steering device (18) and the second motor steering device (17) are installed on the steering connecting rod (19) in series;

and the steering pull rods (21) are respectively connected between the main circulating ball steering gear (13), the auxiliary circulating ball steering gear (14) and the wheels (16).

5. A recirculating ball steering safety redundant system for unmanned commercial vehicles according to claim 4, wherein the first motor steering device (18) comprises:

the first torque motor (1801) is mounted on the steering connecting rod (19) and connected with the EPS controller (2), and the rated output torque of the first torque motor can realize the steering of the vehicle;

the second motor steering device (17) includes:

and a second torque motor (1701) which is attached to the steering link (19), is connected to the unmanned controller, and has a rated output torque capable of steering the vehicle.

6. The unmanned commercial vehicle recirculating ball steering safety redundant system of claim 4, further comprising:

and a torque sensor (22) and a rotation angle sensor (23) which are mounted on the steering link (19) and which detect the torque and the rotation angle of the steering link (19).

7. A control method of a recirculating ball steering redundancy system for unmanned commercial vehicles according to any of claims 1-6, comprising:

and S300, controlling the vehicle to steer according to the control strategy.

8. The control method according to claim 7, wherein the step S200 includes:

9. The control method of claim 8, wherein said providing a hydraulic power source redundancy option comprises:

the platform or the planning layer sends an expected track path of the vehicle;

10. The control method according to claim 7, wherein the step S200 further includes:

11. The control method of claim 10, wherein the providing a steering torque output redundancy selection comprises:

the platform or the planning layer sends an expected track path of the vehicle;

12. The control method according to claim 7, wherein the step S200 further includes:

13. The control method according to claim 12, characterized in that the method comprises:

the platform or the planning layer sends an expected track path of the vehicle;

14. A commercial vehicle comprising a recirculating ball steering redundancy system for unmanned commercial vehicles according to any of claims 1 to 6.