An unmanned driving redundant steering control system

Abstract

The present invention provides an unmanned redundant steering control system, characterized in that the system includes an intelligent driving system ADU, an electronic power steering system EPS, a CAN bus, a fault diagnosis module and a vehicle status monitoring module; the CAN bus includes Chassis-CAN and Private-CAN; the ADU includes a main control unit ADU1 and a redundant control unit ADU2, and when a fault is diagnosed in ADU1, control is switched to ADU2; the EPS includes two independent steering control units EPS1 and EPS2, and when the EPS detects that ADU1 has a communication fault on both CAN buses, it switches to responding to the command of ADU2; the fault diagnosis module can quickly and accurately detect EPS faults, and when one of the steering control units fails, the fault diagnosis module promptly sends a fault signal; after receiving the fault signal, the vehicle status monitoring module completely transfers vehicle control to the other normally working steering control unit.

Description

Technical Field

[0001] The present invention relates to the field of unmanned vehicles, and in particular to an unmanned redundant steering control system. Background Art

[0002] With continuous advancements in artificial intelligence, sensor technology, computer vision, and other fields, autonomous driving technology has experienced rapid growth. As one of the key applications of autonomous driving technology, autonomous vehicles (AVs) demonstrate tremendous potential in areas such as road travel, logistics, and public transportation. However, to achieve the commercialization of AVs, safety must be a primary concern. The steering system, as a key control component of AVs, directly impacts vehicle safety and stability. Existing steering systems typically utilize a single control unit. A failure in this control unit can cause the entire steering system to fail, posing a significant risk to the safe operation of AVs. Furthermore, existing technologies lack self-diagnostic capabilities for faults. When a system malfunctions, manual intervention is often required for troubleshooting and repair, which not only increases maintenance costs but also reduces overall system reliability. Summary of the Invention

[0003] In response to the defects in the existing technology, the purpose of the present invention is to provide an unmanned driving redundant steering control system. By configuring two intelligent driving control units and two independent steering control units, redundant control of the steering system is achieved. When a single control unit fails, the other control unit can quickly take over the work, thereby ensuring the safety and reliability of the unmanned vehicle steering system.

[0004] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0005] An unmanned driving redundant steering control system includes an intelligent driving system (ADU), an electronic power steering (EPS), a CAN bus, a fault diagnosis module, and a vehicle status monitoring module. The interaction interface between the intelligent driving system (ADU) and the electronic power steering (EPS) is a steering wheel angle interface that operates within the full vehicle speed range. During unmanned driving, the intelligent driving system (ADU) sends an angle value request to the electronic power steering (EPS), and the EPS responds to the angle request from the intelligent driving system (ADU) to perform lateral control of the vehicle.

[0006] The CAN bus includes Chassis-CAN and Private-CAN, the Chassis-CAN is the main CAN line, the Private-CAN is the redundant CAN line, both CAN buses use the CANFD protocol, and the intelligent driving system ADU and the electronic power steering system EPS communicate simultaneously on the two CAN buses;

[0007] The intelligent driving system ADU includes a main control unit ADU1 and a redundant control unit ADU2. The main control unit ADU1 and the redundant control unit ADU2 simultaneously send lateral control commands to two CAN buses; the redundant control unit ADU2 also serves as a backup unit to monitor the status of the main control unit ADU1. When a fault is diagnosed in the main control unit ADU1, control is transferred to the redundant control unit ADU2.

[0008] The electronic power steering system (EPS) includes two independent steering control units, EPS1 and EPS2. Both EPS1 and EPS2 are master units, forming a master-master architecture. EPS1 interacts with Chassis-CAN, while EPS2 interacts with Private-CAN. EPS1 and EPS2 interact with each other via Internal-CAN. EPS1 and EPS2 each parse messages received from two CAN buses. The intelligent driving system (ADU) simultaneously determines the status of feedback from EPS1 and EPS2 and performs handshake interaction.

[0009] When the electronic power steering system EPS detects that the main control unit ADU1 has communication failures on both CAN buses, it switches to responding to commands from the redundant control unit ADU2;

[0010] The fault diagnosis module can quickly and accurately detect faults in the electronic power steering system EPS. When a fault occurs in one of the steering control units, the fault diagnosis module will promptly issue a fault signal.

[0011] After receiving the fault signal, the vehicle status monitoring module completely transfers the vehicle control right to another steering control unit that is working normally.

[0012] Preferably, the electronic power steering system EPS has power redundancy and receives power from two power sources at the same time, so when one of the power sources fails, the electronic power steering system EPS still has steering capability.

[0013] Preferably, the electronic power steering system EPS has a redundant torque angle sensor and receives signals from two torque angle sensors at the same time, so when a single sensor fails, the electronic power steering system EPS still has steering capability.

[0014] Preferably, the electronic power steering system EPS has controller redundancy, so in the event that any single steering control unit fails, another redundant steering control unit will provide at least 50% of the maximum steering assist, and at this time the electronic power steering system EPS still has at least 50% of the maximum steering assist capability.

[0015] Preferably, the redundant steering control unit needs to identify the fault condition and start to establish the steering torque within 100ms; after establishing the steering torque, it needs to reach 90% of the torque required to execute the steering angle command or the maximum torque that the redundant steering control unit can output within 300ms, whichever is greater; after reaching the torque requirement, it needs to reach a stable state within 100ms.

[0016] Preferably, the electronic power steering system EPS has motor winding and drive control redundancy, EPS1 and EPS2 each control a single winding in the dual-winding motor, so when a single motor winding fails, the electronic power steering system EPS system still has steering capability.

[0017] Preferably, when the electronic power steering system EPS detects a fault-tolerant fault, it performs backup processing on the fault.

[0018] Preferably, the fault-tolerant faults include: when a communication failure occurs in the main CAN line of the intelligent driving system ADU, EPS1 and EPS2 interact with the outside through redundant CAN lines and Internal-CAN; the electronic power steering system EPS sends fault information and steering assist capability change information to the main CAN line, and optimizes the manual driving steering feel through actual vehicle calibration.

[0019] The unmanned driving redundant steering control system provided by the present invention improves the reliability and safety of the unmanned driving steering control system and reduces the safety risks caused by the failure of a single control unit by introducing a redundant intelligent driving system ADU and an electronic power steering system EPS. Specifically, the redundant steering control system of the present invention is equipped with a main control unit ADU1 and a redundant control unit ADU2. When the main control unit ADU1 has a communication failure on both CAN buses, the electronic power steering system EPS switches to responding to the command of the redundant control unit ADU2. The redundant steering control system of the present invention is also equipped with two independent steering control units EPS1 and EPS2. When any single steering control unit fails, the other redundant steering control unit will provide at least 50% of the maximum steering assist. At this time, the electronic power steering system EPS still has at least 50% of the maximum steering assist capability.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. Redundant control is achieved by configuring two intelligent driving control units and two independent steering control units. When one control unit fails, the other control unit can continue to control the vehicle's steering movement, improving the reliability and safety of the driverless car.

[0022] 2. Equipped with a fault diagnosis module and a vehicle status monitoring module, it has a fault self-diagnosis function, which reduces the system maintenance cost and improves the maintainability of the system. It can also monitor the vehicle status and environmental information in real time, providing accurate data support for fault diagnosis.

[0023] 3. By optimizing the steering control unit switching mechanism, the vehicle's response speed and processing capabilities in the event of a steering control unit failure are improved. Through fast and smooth switching operations, the unmanned vehicle is ensured to remain stable during the switching process, reducing driving risks caused by switching delays. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following drawings:

[0025] Figure 1 This is a system architecture diagram of the intelligent driving system ADU and the electronic power steering system EPS in the embodiment;

[0026] Figure 2 2 is a diagram of the redundant switching process between two steering control units in an embodiment. DETAILED DESCRIPTION

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Generally, the components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0028] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for protection, but merely represents selected embodiments of the present application. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments in the present application without creative work are within the scope of protection of the present application.

[0029] It should be noted that similar numbers and letters represent similar items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined or explained in subsequent figures. In addition, all directional indications in this application (such as up, down, left, right, front, back, bottom...) are only used to explain the relative position relationship, movement, etc. between the components under a specific posture (as shown in the figures). If the specific posture changes, the directional indication will also change accordingly. Furthermore, the descriptions of "first", "second", etc. in the application are for descriptive purposes only and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features.

[0030] like Figure 1 Figure 2 shows the unmanned redundant steering control system in this embodiment. The system includes an intelligent driving system (ADU), an electronic power steering (EPS), a CAN bus, a fault diagnosis module, and a vehicle status monitoring module. The interface between the ADU and the EPS is a steering wheel angle interface that operates over the full vehicle speed range. During autonomous driving, the ADU sends angle value requests to the EPS, which then responds to the ADU's angle requests to provide lateral control of the vehicle.

[0031] The CAN bus includes Chassis-CAN and Private-CAN, where Chassis-CAN is the main CAN line and Private-CAN is the redundant CAN line. Both CAN buses use the CANFD protocol. The intelligent driving system ADU and the electronic power steering system EPS communicate on the two CAN buses at the same time.

[0032] The intelligent driving system ADU consists of a primary control unit (ADU1) and a redundant control unit (ADU2). Both units simultaneously send lateral control commands to two CAN buses. ADU2 also serves as a backup unit, monitoring the status of ADU1. If a fault is detected in ADU1, control is transferred to ADU2.

[0033] The electronic power steering (EPS) system consists of two independent steering control units, EPS1 and EPS2. Both EPS1 and EPS2 are master units, employing a master-master architecture. EPS1 interacts with the Chassis CAN bus, while EPS2 interacts with the Private CAN bus. The two communicate with each other via the Internal CAN bus. EPS1 and EPS2 independently parse messages received on the two CAN buses. Because EPS1 and EPS2 operate in a master-master architecture, the intelligent driving system (ADU) must simultaneously determine the status of both EPS1 and EPS2 and perform handshake interactions.

[0034] When the electronic power steering system EPS detects that the main control unit ADU1 has communication failures on both CAN buses, it switches to responding to commands from the redundant control unit ADU2.

[0035] The fault diagnosis module can quickly and accurately detect faults in the electronic power steering system EPS. When one of the steering control units fails, the fault diagnosis module will issue a fault signal in a timely manner.

[0036] When the vehicle status monitoring module receives a fault signal, it completely transfers vehicle control to another steering control unit that is functioning normally.

[0037] This embodiment provides an unmanned driving redundant steering control system, wherein the electronic power steering (EPS) system has power redundancy. The EPS system receives power from two power sources simultaneously. If one power source fails, the EPS system still has steering capability.

[0038] This embodiment provides an unmanned driving redundant steering control system, in which the electronic power steering (EPS) system has redundant torque angle sensors. The EPS system simultaneously receives signals from two torque angle sensors. If a single sensor fails, the EPS system still has steering capabilities.

[0039] like Figure 2 As shown, this embodiment provides an unmanned redundant steering control system, in which the electronic power steering (EPS) system has controller redundancy. If any single steering control unit fails, the other redundant steering control unit will provide at least 50% of the maximum steering force, thus maintaining at least 50% of the maximum steering force capability. Furthermore, the redundant steering control unit must recognize a fault and begin building steering torque within 100ms. After establishing steering torque, it must reach 90% of the torque required to execute the steering angle command or the maximum torque output by the redundant steering control unit, whichever is greater, within 300ms. Once the torque requirement is reached, it must reach a stable state within 100ms.

[0040] This embodiment provides an unmanned redundant steering control system, in which the electronic power steering (EPS) system has motor winding and drive control redundancy. EPS1 and EPS2 each control a single winding in a dual-winding motor. If a single motor winding fails, the EPS system still maintains steering capability.

[0041] This embodiment provides an unmanned driving redundant steering control system in which the electronic power steering (EPS) system performs backup processing when it detects a fault-tolerant fault. For example, if a communication failure occurs on the main CAN line (Chassis-CAN) of the intelligent driving system (ADU), EPS1 and EPS2 can communicate with the outside world using the redundant CAN line (Private-CAN) and the internal CAN line (Internal-CAN). At this time, the electronic power steering system (EPS) system sends fault information and information about changes in steering assist capabilities, such as basic assist, active self-centering, rack end protection, and damping control during manual driving, to the main CAN line. Furthermore, the EPS system optimizes the steering feel of manual driving through real-vehicle calibration.

[0042] The above describes the specific embodiments of the present invention. Based on the above description, relevant personnel can make various changes and modifications without departing from the scope of the technical concept of this invention.

Claims

1. An unmanned driving redundant steering control system, characterized in that: The system includes an intelligent driving system (ADU), an electronic power steering (EPS), a CAN bus, a fault diagnosis module, and a vehicle status monitoring module. The interaction interface between the intelligent driving system (ADU) and the electronic power steering (EPS) is a steering wheel angle interface within the full vehicle speed range. During unmanned driving, the intelligent driving system (ADU) sends an angle value request to the electronic power steering (EPS), and the electronic power steering (EPS) responds to the angle request from the intelligent driving system (ADU) to perform lateral control of the vehicle. The CAN bus includes Chassis-CAN and Private-CAN, the Chassis-CAN is the main CAN line, the Private-CAN is the redundant CAN line, both CAN buses use the CANFD protocol, and the intelligent driving system ADU and the electronic power steering system EPS communicate simultaneously on the two CAN buses; The intelligent driving system ADU includes a main control unit ADU1 and a redundant control unit ADU2. The main control unit ADU1 and the redundant control unit ADU2 simultaneously send lateral control commands to two CAN buses; the redundant control unit ADU2 also serves as a backup unit to monitor the status of the main control unit ADU1. When a fault is diagnosed in the main control unit ADU1, control is transferred to the redundant control unit ADU2. The electronic power steering system (EPS) includes two independent steering control units, EPS1 and EPS2. Both EPS1 and EPS2 are master units, forming a master-master architecture. EPS1 interacts with Chassis-CAN, while EPS2 interacts with Private-CAN. EPS1 and EPS2 interact with each other via Internal-CAN. EPS1 and EPS2 each parse messages received from two CAN buses. The intelligent driving system (ADU) simultaneously determines the status of feedback from EPS1 and EPS2 and performs handshake interaction. When the electronic power steering system EPS detects that the main control unit ADU1 has communication failures on both CAN buses, it switches to responding to commands from the redundant control unit ADU2; The fault diagnosis module can quickly and accurately detect faults in the electronic power steering system EPS. When a fault occurs in one of the steering control units, the fault diagnosis module will promptly issue a fault signal. After receiving the fault signal, the vehicle status monitoring module completely transfers the vehicle control right to another steering control unit that is working normally.

2. The unmanned driving redundant steering control system according to claim 1, characterized in that: The electronic power steering system EPS has power redundancy and receives power from two power sources at the same time. Therefore, when one of the power sources fails, the electronic power steering system EPS still has steering capability.

3. The unmanned driving redundant steering control system according to claim 1, characterized in that: The electronic power steering system EPS has a redundant torque angle sensor and receives signals from two torque angle sensors at the same time. Therefore, when a single sensor fails, the electronic power steering system EPS still has steering capability.

4. The unmanned driving redundant steering control system according to claim 1, characterized in that: The electronic power steering system EPS has controller redundancy, so if any single steering control unit fails, the other redundant steering control unit will provide at least 50% of the maximum steering assist force. At this time, the electronic power steering system EPS still has at least 50% of the maximum steering assist force capability.

5. The unmanned driving redundant steering control system according to claim 4, characterized in that: The redundant steering control unit needs to identify a fault condition and begin to establish steering torque within 100ms; after establishing the steering torque, it needs to reach 90% of the torque required to execute the steering angle command or the maximum torque that the redundant steering control unit can output within 300ms, whichever is greater; after reaching the torque requirement, it needs to reach a stable state within 100ms.

6. The unmanned driving redundant steering control system according to claim 1, characterized in that: The electronic power steering system EPS has motor winding and drive control redundancy. EPS1 and EPS2 each control a single winding in the dual-winding motor. Therefore, when a single motor winding fails, the electronic power steering system EPS still has steering capability.

7. The unmanned driving redundant steering control system according to claim 1, characterized in that: When the electronic power steering system EPS detects a fault-tolerant fault, the fault is backed up.

8. The unmanned driving redundant steering control system according to claim 7, characterized in that: The fault-tolerant faults include: when the intelligent driving system ADU has a communication failure on the main CAN line, EPS1 and EPS2 interact with the outside through redundant CAN lines and Internal-CAN; the electronic power steering system EPS sends fault information and steering assist capability change information to the main CAN line, and optimizes the manual driving steering feel through actual vehicle calibration.

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