CN118784130A - Time synchronization method, storage medium and electronic device - Google Patents

Abstract

An embodiment of the present invention provides a time synchronization method, a storage medium and an electronic device, the method comprising: within a specified time period after a domain controller is powered on, in response to a received time acquisition request, obtaining network time through a mobile communication network, and sending the network time to the domain controller, wherein the time acquisition request is a request sent by the domain controller to a positioning box Pbox; obtaining a first synchronization time sent by the domain controller, wherein the domain controller is used to synchronize time for at least one slave device, the at least one slave device includes a Pbox, the first synchronization time is the time obtained by updating the local time of the domain controller with the network time as the starting time, and the local time of the domain controller is the time provided by a first timer in the domain controller; based on the first synchronization time, updating the local time of the Pbox to a second synchronization time, wherein the first synchronization time is synchronized with the second synchronization time.

Description

Time synchronization method, storage medium and electronic device

Technical Field

Embodiments of the present invention relate to the field of autonomous driving, and in particular, to a time synchronization method, a storage medium, and an electronic device.

Background Art

Pbox (positioning box) is a device used to provide high-precision positioning in intelligent driving systems. It usually integrates the Global Navigation Satellite System (GNSS) and INS (Inertial Navigation System) to provide precise position and attitude information of the vehicle. Time synchronization within the Pbox is essential to ensure the accuracy of navigation data.

The time synchronization method in the related technology is to use the PPS (Pulse Per Second) signal and GPRMC (Global Positioning System Recommended Minimum Navigation Information) data given by the Pbox, and the domain controller (referred to as domain controller) receives and parses and synchronizes them; in scenarios where there is no satellite signal such as in the basement, due to the lack of PPS output, the domain controller cannot be synchronized with the time, and when the vehicle drives to the road and waits for the satellite signal, the time will jump.

It can be seen that the time synchronization method in the related art has the problem that the vehicle cannot perform time synchronization in a scenario where there is no satellite signal.

Summary of the invention

The embodiments of the present invention provide a time synchronization method, a storage medium and an electronic device to at least solve the problem that the time synchronization method in the related art cannot perform time synchronization when there is no satellite signal.

According to one embodiment of the present invention, there is provided a time synchronization method, comprising: within a specified time period after a domain controller is powered on, in response to a received time acquisition request, acquiring network time through a mobile communication network, and sending the network time to the domain controller, wherein the time acquisition request is a request sent by the domain controller to a positioning box Pbox; acquiring a first synchronization time sent by the domain controller, wherein the domain controller is used to perform time synchronization on at least one slave device, the at least one slave device includes the Pbox, the first synchronization time is the time obtained by updating the local time of the domain controller with the network time as the starting time, and the local time of the domain controller is the time provided by a first timer in the domain controller; based on the first synchronization time, updating the local time of the Pbox to a second synchronization time, wherein the first synchronization time is synchronized with the second synchronization time.

In an exemplary embodiment, the obtaining of network time through a mobile communication network in response to a received time acquisition request includes: obtaining the network time through the mobile communication network in response to the received time acquisition request when the Pbox cannot detect a satellite signal.

In an exemplary embodiment, updating the local time of the Pbox to the second synchronization time based on the first synchronization time includes: when the local time of the Pbox is the time provided by the second timer in the Pbox, updating the current time provided by the second timer in the Pbox to the second synchronization time, and controlling the second timer to continue timing from the second synchronization time, wherein the second synchronization time is equal to the time obtained by adding the first synchronization time to a first time difference, the first time difference is the difference obtained by subtracting the first time from the current time provided by the second timer, and the first time is the time of the second timer when the Pbox receives the first synchronization time.

In an exemplary embodiment, after updating the local time of the Pbox to the second synchronization time based on the first synchronization time, the method further includes: updating the timestamp when the sensor data in the vehicle-side data is collected to a timestamp synchronized with the second synchronization time based on the second synchronization time, wherein the vehicle-side data includes the sensor data of the vehicle collected by the Pbox and the timestamp when the sensor data is collected.

In an exemplary embodiment, after the local time of the Pbox is updated to the second synchronization time based on the first synchronization time, the method further includes: when the domain controller receives roadside data, based on the second synchronization time, updating the timestamp when the sensor data in the roadside data is collected to a timestamp synchronized with the second synchronization time, wherein the roadside data includes the sensor data collected by a device outside the vehicle and the timestamp when the sensor data is collected.

In an exemplary embodiment, based on the second synchronization time, the timestamp when the sensor data in the roadside data is collected is updated to a timestamp synchronized with the second synchronization time, including: when the Pbox receives the world standard time through the global navigation satellite system GNSS antenna, the timestamp when the sensor data in the roadside data is collected is added to a third time difference to obtain a timestamp synchronized with the second synchronization time, wherein the timestamp when the sensor data in the roadside data is collected is a timestamp determined based on the world standard time, and the third time difference is the difference obtained by subtracting the world standard time from the time provided by the second timer in the Pbox when the Pbox receives the world standard time through the GNSS antenna.

In an exemplary embodiment, after updating the timestamp of when the sensor data in the roadside data is collected to a timestamp synchronized with the second synchronization time based on the second synchronization time, the method further includes: when the timestamp of when the sensor data in the vehicle-side data is collected is updated to a timestamp synchronized with the second synchronization time, determining vehicle environment data based on the vehicle-side data after the updated timestamp and the roadside data after the updated timestamp, wherein the vehicle-side data includes the sensor data of the vehicle collected by the Pbox and the timestamp when the sensor data is collected, and the vehicle environment data is used to indicate the location of the vehicle.

According to another embodiment of the present invention, a time synchronization method is provided, comprising: sending a time acquisition request to a positioning box Pbox within a specified time period after a domain controller is powered on, wherein the domain controller is used to perform time synchronization on at least one slave device, and the at least one slave device includes the Pbox; acquiring the network time sent by the Pbox in response to the time acquisition request, wherein the network time is the time acquired by the Pbox through a mobile communication network; based on the network time, updating the local time of the domain controller to a first synchronization time, and controlling a first timer in the domain controller to continue timing from the first synchronization time, wherein the local time of the domain controller is the time provided by the first timer in the domain controller; sending the first synchronization time to the Pbox, wherein the first synchronization time is used to update the local time of the Pbox to a second synchronization time, wherein the first synchronization time is synchronized with the second synchronization time.

According to another embodiment of the present invention, a time synchronization device is provided, comprising: a first execution unit, for acquiring network time through a mobile communication network in response to a received time acquisition request within a specified time period after the domain controller is powered on, and sending the network time to the domain controller, wherein the time acquisition request is a request sent by the domain controller to a positioning box Pbox; a first acquisition unit, for acquiring a first synchronization time sent by the domain controller, wherein the domain controller is used to perform time synchronization on at least one slave device, the at least one slave device includes the Pbox, the first synchronization time is the time obtained by updating the local time of the domain controller with the network time as the starting time, and the local time of the domain controller is the time provided by a first timer in the domain controller; a first update unit, for updating the local time of the Pbox to a second synchronization time based on the first synchronization time, wherein the first synchronization time is synchronized with the second synchronization time.

In an exemplary embodiment, the first execution unit includes: an acquisition module, which is used to acquire the network time through the mobile communication network in response to the received time acquisition request when the Pbox cannot detect a satellite signal.

In an exemplary embodiment, the first update unit includes: a first execution module, which is used to update the current time provided by the second timer in the Pbox to the second synchronization time when the local time of the Pbox is the time provided by the second timer in the Pbox, and control the second timer to continue timing from the second synchronization time, wherein the second synchronization time is equal to the time obtained by adding the first synchronization time to the first time difference, the first time difference is the difference obtained by subtracting the first time from the current time provided by the second timer, and the first time is the time of the second timer when the Pbox receives the first synchronization time.

In an exemplary embodiment, the device also includes: a second updating unit, which is used to update the local time of the Pbox to a second synchronization time based on the first synchronization time, and then, based on the second synchronization time, update the timestamp when the sensor data in the vehicle-side data is collected to a timestamp synchronized with the second synchronization time, wherein the vehicle-side data includes the sensor data of the vehicle collected by the Pbox and the timestamp when the sensor data is collected.

In an exemplary embodiment, the device also includes: a third updating unit, which is used to update the timestamp when the sensor data in the roadside data is collected to a timestamp synchronized with the second synchronization time based on the second synchronization time after the local time of the Pbox is updated to the second synchronization time based on the first synchronization time when the domain controller receives the roadside data, wherein the roadside data includes the sensor data collected by the device outside the vehicle and the timestamp when the sensor data is collected.

In an exemplary embodiment, the third update unit includes: a second execution module, which is used to add the timestamp when the sensor data in the roadside data is collected to the third time difference to obtain a timestamp synchronized with the second synchronization time when the Pbox receives the world standard time through the global navigation satellite system GNSS antenna, wherein the timestamp when the sensor data in the roadside data is collected is a timestamp determined based on the world standard time, and the third time difference is the difference obtained by subtracting the world standard time from the time provided by the second timer in the Pbox when the Pbox receives the world standard time through the GNSS antenna.

In an exemplary embodiment, the device also includes: a determination unit, which is used to update the timestamp of when the sensor data in the roadside data is collected to a timestamp synchronized with the second synchronization time based on the second synchronization time, and when the timestamp of when the sensor data in the vehicle-side data is collected is updated to a timestamp synchronized with the second synchronization time, determine the vehicle environment data based on the vehicle-side data after the updated timestamp and the roadside data after the updated timestamp, wherein the vehicle-side data includes the sensor data of the vehicle collected by the Pbox and the timestamp when the sensor data is collected, and the vehicle environment data is used to indicate the location of the vehicle.

According to another embodiment of the present invention, a time synchronization device is provided, comprising: a first sending unit, configured to send a time acquisition request to a positioning box Pbox within a specified time period after a domain controller is powered on, wherein the domain controller is configured to perform time synchronization on at least one slave device, and the at least one slave device includes the Pbox; a second acquisition unit, configured to acquire a network time sent by the Pbox in response to the time acquisition request, wherein the network time is the time acquired by the Pbox through a mobile communication network; a second execution unit, configured to update the local time of the domain controller to a first synchronization time based on the network time, and control a first timer in the domain controller to continue timing from the first synchronization time, wherein the local time of the domain controller is the time provided by the first timer in the domain controller; a second sending unit, configured to send the first synchronization time to the Pbox, wherein the first synchronization time is used to update the local time of the Pbox to a second synchronization time, wherein the first synchronization time is synchronized with the second synchronization time.

According to yet another embodiment of the present invention, a computer-readable storage medium is provided, in which a computer program is stored, wherein the computer program is configured to execute the steps of any one of the above method embodiments when run.

According to yet another embodiment of the present invention, there is provided an electronic device, including a memory and a processor, wherein the memory stores a computer program, and the processor is configured to run the computer program to execute the steps in any one of the above method embodiments.

According to yet another embodiment of the present invention, a computer program product is provided, including a computer program, and when the computer program is executed by a processor, the steps in any one of the above method embodiments are implemented.

Through the present invention, since the mobile communication network is used to obtain the network time as the starting time of the local time of the domain controller, there is no need to rely on satellite signals, and the domain controller is used as the master device to synchronize the time of other slave devices in the vehicle system, the temporal consistency of data from different sensors and devices can be ensured. Therefore, the problem that the time synchronization method in the related art cannot synchronize the vehicle in the scenario without satellite signals can be solved, and the effect of not relying on satellite signals for time synchronization in the scenario of single-vehicle intelligence can be achieved.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a hardware structure block diagram of a time synchronization method according to an embodiment of the present invention;

FIG2 is a schematic flow chart of a time synchronization method according to an embodiment of the present invention;

FIG3 is a schematic diagram of a time synchronization method according to an embodiment of the present invention;

FIG4 is a schematic diagram of another time synchronization method according to an embodiment of the present invention;

FIG5 is a schematic diagram of another time synchronization method according to an embodiment of the present invention;

FIG6 is a schematic flow chart of another time synchronization method according to an embodiment of the present invention;

7 is a structural block diagram of a time synchronization device according to an embodiment of the present invention;

FIG. 8 is a structural block diagram of another time synchronization device according to an embodiment of the present invention.

DETAILED DESCRIPTION

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings and in combination with the embodiments.

It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

The method embodiment provided in the embodiment of the present invention can be executed in a vehicle. FIG1 is a hardware structure block diagram of a time synchronization method in an embodiment of the present invention. As shown in FIG1 , the time synchronization system includes a domain controller and a Pbox, wherein the domain controller includes a first timer, and the Pbox includes a second timer. It should be noted that the Pbox also includes a communication module (not shown in FIG1 ) that can access a mobile communication network.

In this embodiment, a time synchronization method running on a vehicle is provided. FIG. 2 is a flow chart of a time synchronization method according to an embodiment of the present invention. As shown in FIG. 2 , the flow chart includes the following steps:

Step S202, within a specified time period after the domain controller is powered on, in response to a received time acquisition request, obtain network time through a mobile communication network and send the network time to the domain controller, wherein the time acquisition request is a request sent by the domain controller to the positioning box Pbox.

The time synchronization method in this embodiment can be applied to the scenario of time synchronization in an autonomous driving system. In an autonomous driving system, time synchronization refers to the precise alignment of the clocks of various sensors, controllers, and actuators to ensure that all components within the system can operate under a unified time reference. Time synchronization is essential for achieving accurate data processing and decision-making.

In the autonomous driving system, the domain controller is a centralized control unit responsible for managing and coordinating the work of each subsystem within the system. The main functions of the domain controller include: data fusion: integrating data from different sensors to generate consistent and accurate environmental perception information; task allocation: reasonably allocating tasks according to the system requirements and the capabilities of each subsystem to achieve optimal use of resources; decision making: formulating appropriate driving strategies and control instructions based on environmental perception information and task allocation results; system monitoring: real-time monitoring of the system status to ensure that each component is working properly and to detect and handle abnormal situations in a timely manner. The high-precision positioning box Pbox (Precision Positioning Box) is a high-precision positioning device designed specifically for the field of autonomous driving. Its main function is to provide accurate position, speed and time information to support the safe, stable and efficient operation of autonomous driving vehicles in various complex environments.

At present, the time synchronization method in related technologies is to use the PPS signal (IO) and GPRMC data (UART) given by the Pbox, which are received by the domain controller for analysis and synchronization. In scenarios where there is no satellite signal, such as in underground garages, there is no PPS output, and it is impossible to provide time synchronization to the domain controller.

In order to at least partially solve the above problems, in this embodiment, the Pbox obtains network time through the mobile communication network and sends the network time to the domain controller. The domain controller can use the obtained network world as the starting time of the local time, continue timing based on the starting time, and regularly synchronize the time of slave devices including the Pbox, so as to achieve time synchronization even in the absence of satellite signal lights, thereby solving the problem that the autonomous driving vehicle cannot obtain time when there is no satellite started in the basement.

In this embodiment, for Pbox, within a specified time period after the domain controller is powered on, it can respond to a received time acquisition request, obtain network time through the mobile communication network, and send the network time to the domain controller, wherein the time acquisition request is a request sent by the domain controller to Pbox.

For example, in this embodiment, within 5 seconds (this time can be reasonably set according to actual conditions) after the domain controller is powered on, the initial time value is obtained from the Pbox through CAN, Ethernet or other means as the starting clock of the domain controller's local clock.

The Pbox can be equipped with a 4G/5G module, access the network through a SIM card or ESIM, and obtain network time (the network time is not very accurate, but can be used as the starting time).

The 4G/5G module is equipped here to obtain the network time so that a time that is closer to the real time can be output when the machine is turned on. On the one hand, it can cope with scenes without satellite signals such as basements, so that the domain controller has a start time; on the other hand, it provides users with a consistent usage time. Without this design, the time that users see when starting up in scenes without satellite signals such as basements may be a fixed time (such as January 1, 1970). When the machine is on the road and there is a satellite signal, the time will jump to the current time.

Step S204, obtaining a first synchronization time sent by the domain controller, wherein the domain controller is used to synchronize time for at least one slave device, the at least one slave device includes a Pbox, the first synchronization time is a time obtained by updating the local time of the domain controller using the network time as the start time, and the local time of the domain controller is a time provided by a first timer in the domain controller;

In this embodiment, the domain controller serves as the master device of the time synchronization domain; all other sensors, including Pbox, serve as slave devices of the synchronization domain; the domain controller provides time synchronization to the slave devices, and the synchronization modes include PTP, gPTP, and CAN TSN, which are reasonably configured according to the synchronization mode supported by the slave.

Optionally, in this embodiment, the time synchronization domain refers to achieving accurate time synchronization between multiple sensors and system components. The main goal of the time synchronization domain is to ensure that all sensors, controllers, and actuators work under the same time reference to facilitate data consistency and decision accuracy.

Here, PTP (Precision Time Protocol), gPTP (Generalized Precision Time Protocol) and CAN TSN (Controller Area Network Time-Sensitive Networking) are three different time synchronization protocols, which are widely used in industrial automation, communication networks and the Internet of Things. Specifically:

PTP (Precision Time Protocol): Precision Time Protocol, mainly used for time synchronization in computer networks. PTP is a network protocol that achieves high-precision time synchronization by exchanging time information between network devices. There are two versions of PTP: PTPv1 and PTPv2. PTPv1 focuses on time synchronization in local area networks (LANs), while PTPv2 expands on PTPv1 to support a wider range of application scenarios, including wide area networks (WANs) and distributed systems.

gPTP (Generalized Precision Time Protocol): Generalized Precision Time Protocol is an extension of PTP. gPTP is an improvement on PTP to meet a wider range of application requirements. gPTP supports a variety of network topologies, including ring, tree, mesh, etc., while providing better time synchronization accuracy and flexibility.

CAN TSN (Controller Area Network Time-Sensitive Networking): Controller Area Network Time-Sensitive Networking is a network communication technology based on the CAN (Controller Area Network) protocol. CAN TSN adds time synchronization function on the basis of the traditional CAN protocol to meet the needs of real-time and deterministic communication. CAN TSN is mainly used in the fields of automobiles, industrial automation, etc., and can achieve high-speed, low-latency data transmission and time synchronization.

The local time of the domain controller is the time provided by the first timer in the domain controller. After obtaining the network time from the Pbox, the first timer continues to time with the network time as the starting time.

Step S206: based on the first synchronization time, update the local time of the Pbox to the second synchronization time, wherein the first synchronization time is synchronized with the second synchronization time.

For Pbox, Pbox acts as the slave device of the entire time synchronization domain and accepts time synchronization from the domain control master. After Pbox is synchronized, the second timer in Pbox is obtained as the time base of the entire Pbox data.

Optionally, in this embodiment, the time reference provided by the second timer timer can be used to time stamp the positioning inertial navigation data.

In this embodiment, the IMU (Inertial Measurement Unit) can exist independently in the form of a P-Box (i.e., the positioning devices including the IMU are packaged in a box). The IMU is the core hardware in the INS (Inertial Navigation System). The Positioning and Inertial Navigation Data (Positioning and Inertial Navigation Data) can refer to the data generated by the INS, including position, speed, direction and other motion parameters. The inertial navigation system is an autonomous navigation system that does not rely on external signals. It measures and calculates the motion state of an object through sensors (such as accelerometers and gyroscopes).

Based on the first synchronization time sent by the domain controller, the local time of the Pbox can be updated to the second synchronization time, that is, the time of the second timer timer in the Pbox is updated to the second synchronization time to achieve synchronization between the first synchronization time of the domain controller and the second synchronization time of the Pbox.

After the local time of the second timer timer in the Pbox is updated to the second synchronization time, the second timer timer in the Pbox continues timing from the second synchronization time.

Through the above steps, within a specified time period after the domain controller is powered on, in response to the received time acquisition request, the network time is acquired through the mobile communication network, and the network time is sent to the domain controller, wherein the time acquisition request is a request sent by the domain controller to the positioning box Pbox; the first synchronization time sent by the domain controller is acquired, wherein the domain controller is used to synchronize the time of at least one slave device, and the at least one slave device includes a Pbox, and the first synchronization time is the time obtained by updating the local time of the domain controller with the network time as the starting time, and the local time of the domain controller is the time provided by the first timer in the domain controller; based on the first synchronization time, the local time of the Pbox is updated to the second synchronization time, wherein the first synchronization time is synchronized with the second synchronization time, which solves the problem in the time synchronization method in the related art that the vehicle cannot synchronize the time in a scenario where there is no satellite signal.

The execution subject of the above steps may be a Pbox on the vehicle, but is not limited thereto.

In an exemplary embodiment, in response to a received time acquisition request, acquiring network time through a mobile communication network includes:

S11, when the Pbox cannot detect a satellite signal, in response to a received time acquisition request, acquire network time through a mobile communication network.

In the related technology, the time synchronization of a single vehicle needs to rely on satellite signals. In the scenario where there is no satellite signal, it is impossible to synchronize the time of the domain controller based on the Pbox. In this embodiment, when the Pbox cannot detect the satellite signal, it can respond to the received time acquisition request and obtain the network time through the mobile communication network.

The situations where the Pbox cannot detect satellite signals may include but are not limited to the following scenarios:

Tunnels or underground environments: In enclosed spaces such as tunnels or underground parking lots, satellite signals may not be able to penetrate thick concrete or mountains.

Areas with tall buildings: In urban areas with tall buildings, buildings may block or reflect satellite signals, causing signal loss or instability.

Severe weather conditions: Certain extreme weather conditions, such as storms, may interfere with or degrade satellite signals.

Similar to the above-mentioned embodiment, the Pbox may be internally configured with hardware for realizing wireless communication so as to connect to a mobile communication network. The network time may refer to the time on the network operator's server, and the Pbox may obtain the network time by connecting to the network.

Optionally, in this embodiment, when network time acquisition fails, a high-precision vehicle-mounted clock (such as a rubidium clock or a constant temperature crystal oscillator) can be used as a time reference to provide a unified time base for all devices in the system. Time can also be synchronized through manual settings.

In an exemplary embodiment, based on the first synchronization time, updating the local time of the Pbox to the second synchronization time includes:

S21, when the local time of the Pbox is the time provided by the second timer in the Pbox, update the current time provided by the second timer in the Pbox to the second synchronization time, and control the second timer to continue timing from the second synchronization time, wherein the second synchronization time is equal to the time obtained by adding the first synchronization time to the first time difference, the first time difference is the difference obtained by subtracting the first time from the current time provided by the second timer, and the first time is the time of the second timer when the Pbox receives the first synchronization time.

Taking into account that time is dynamic, in order to improve the accuracy of time synchronization, in this embodiment, there may be a difference (i.e., the first time difference) between when the Pbox receives the first synchronization time and when the Pbox updates the second timer. In order to reduce the impact of the difference on the accuracy of time synchronization, the difference may be compensated.

Optionally, in combination with Figure 3, in this embodiment, when the local time of the Pbox is the time provided by the second timer in the Pbox, the current time T1 provided by the second timer in the Pbox is updated to the second synchronization time T2, and the second timer is controlled to continue timing from the second synchronization time T2, wherein the second synchronization time T2 is equal to the time obtained by adding the first synchronization time t1 and the first time difference △T, the first time difference is the difference obtained by subtracting the first time from the current time T1 provided by the second timer, and the first time is the time T0 of the second timer when the Pbox receives the first synchronization time t1.

For example, taking the first synchronization time t1 as 10:30:00:111 milliseconds on June 23, 2024, T0 as 10:30:00:107 milliseconds on June 23, 2024, and T1 as 10:30:00:108 milliseconds on June 23, 2024, the second synchronization time T2 is 10:30:00:112 milliseconds on June 23, 2024.

Similarly, the first synchronization time t1 obtained by Pbox from the domain controller can be obtained after delay compensation, that is, the time sent from the domain controller and the time received by Pbox may not be exactly the same time. The first synchronization time t1 obtained by Pbox from the domain controller can be obtained by adding the time sent from the domain controller to the transmission time, that is, the first synchronization time t1 is obtained after delay compensation.

Through this embodiment, by performing delay compensation on the acquired time at the Pbox end, the accuracy of the updated Pbox time can be improved.

In an exemplary embodiment, after updating the local time of the Pbox to the second synchronization time based on the first synchronization time, the method further includes:

S31, based on the second synchronization time, updating the timestamp when the sensor data in the vehicle-side data is collected to a timestamp synchronized with the second synchronization time, wherein the vehicle-side data includes the sensor data of the vehicle collected by the Pbox and the timestamp when the sensor data is collected.

In order to improve the synchronization of sensor data, after synchronizing the time of the slave device based on the time of the domain controller, the newly collected sensor data can be timestamped based on the synchronized time, and the timestamp of the sensor data before the time synchronization can be updated to ensure that the data collected from each sensor is consistent at the same time point, thereby improving the accuracy of data processing.

Here, the vehicle-side data mainly comes from the vehicle's own sensors and systems, including but not limited to:

On-board camera: Provides visual information of the vehicle's surroundings.

LiDAR: Used to accurately measure the distance and speed of objects around the vehicle.

Vehicle information system: including vehicle status, location, speed and other information.

In-vehicle navigation system: provides navigation and positioning data for the vehicle.

On-vehicle sensor network: collects vehicle operating status and environmental data, such as acceleration, steering angle, etc.

Optionally, in this embodiment, the timestamp when the sensor data in the vehicle-side data is collected is updated to the target timestamp, wherein the target timestamp is the timestamp obtained by adding the timestamp when the sensor data in the vehicle-side data is collected to the second time difference, and the second time difference is the time difference before and after the local time of the Pbox is updated, that is, the local time of the Pbox before the update is subtracted from the second synchronization time.

That is, the timestamp when the sensor data in the vehicle-side data is collected plus the second synchronization time minus the local time of the Pbox before updating equals the target timestamp.

Through this embodiment, by updating the timestamp of the vehicle-side data, the data collected by various sensors on the vehicle-side can be made consistent at the same time point, thereby improving the accuracy of data processing.

In an exemplary embodiment, after updating the local time of the Pbox to the second synchronization time based on the first synchronization time, the method further includes:

S41, when the domain controller receives the roadside data, based on the second synchronization time, the timestamp when the sensor data in the roadside data is collected is updated to a timestamp synchronized with the second synchronization time, wherein the roadside data includes sensor data collected by equipment outside the vehicle and the timestamp when the sensor data is collected.

Optionally, in this embodiment, the roadside data mainly comes from sensors and systems of road infrastructure, including but not limited to:

Roadside cameras: monitor road conditions, including traffic flow, vehicle behavior, etc.

Roadside LiDAR: Provides accurate distance and speed measurements over a wider area.

Roadside communication unit: such as RSU (Road Side Unit), responsible for exchanging information with vehicles.

Traffic signal control system: provides traffic light status and timing information.

Roadside environmental monitoring equipment: monitors environmental factors such as weather and road conditions.

Roadside information release system: provides vehicles with traffic information, road condition warnings, etc.

Roadside sensor network: collects data on roadside infrastructure status and surrounding environment.

It should be noted that when the domain controller receives roadside data, the Pbox can receive satellite signals. For example, in this embodiment, in conjunction with Figure 5, the domain controller receives roadside data in a vehicle-road collaboration scenario, and V2X (Vehicle-to-Everything) data is accessed. The timestamp of the V2X data is synchronized with the GPS (Global Positioning System) on the roadside. When the V2X data enters the domain controller, the timestamp of the V2X data needs to be normalized to the local time of the domain controller before the V2X data can be fused. When the domain controller receives roadside data, based on the second synchronization time, the timestamp of the sensor data in the roadside data when it is collected is updated to a timestamp synchronized with the second synchronization time.

Through this embodiment, in the scenario of vehicle-road collaboration, by adjusting the timestamp of the roadside data connected to the domain controller to a timestamp corresponding to the time reference of the domain controller, the accuracy of data fusion can be improved.

In an exemplary embodiment, based on the second synchronization time, updating the timestamp when the sensor data in the roadside data is collected to a timestamp synchronized with the second synchronization time includes:

S51, when the Pbox receives the world standard time through the global navigation satellite system GNSS antenna, the timestamp when the sensor data in the roadside data is collected is added to the third time difference to obtain a timestamp synchronized with the second synchronization time, wherein the timestamp when the sensor data in the roadside data is collected is a timestamp determined based on the world standard time, and the third time difference is the difference obtained by subtracting the world standard time from the time provided by the second timer in the Pbox when the Pbox receives the world standard time through the GNSS antenna.

Optionally, in this embodiment, when the Pbox receives the world standard time through the global navigation satellite system GNSS antenna and the time of the second timer is greater than the world standard time, the timestamp when the sensor data in the roadside data is collected is added to the third time difference to obtain a timestamp synchronized with the second synchronization time, wherein the timestamp when the sensor data in the roadside data is collected is a timestamp determined based on the world standard time, and the third time difference is the difference obtained by subtracting the received world standard time from the time provided by the second timer when the Pbox receives the world standard time through the GNSS antenna;

When the Pbox receives the world standard time through the global navigation satellite system GNSS antenna and the time of the second timer is less than the world standard time, the timestamp when the sensor data in the roadside data is collected is subtracted from the fourth time difference to obtain a timestamp synchronized with the second synchronization time, wherein the timestamp when the sensor data in the roadside data is collected is a timestamp determined based on the world standard time, and the fourth time difference is the difference obtained by subtracting the time provided by the second timer when the Pbox receives the world standard time through the GNSS antenna from the received world standard time.

For example, in this embodiment, in conjunction with FIG4 , the Pbox can obtain UTC (Coordinated Universal Time, also known as World Standard Time) time through the GNSS antenna. The difference Δt between the Pbox local timer (i.e., the second timer) and the UTC time is calculated periodically (1 second or 0.1 second) (i.e., the difference obtained by subtracting the world standard time from the time provided by the second timer in the Pbox when the Pbox receives the world standard time through the GNSS antenna), and Δt is sent to the domain controller via CAN, Ethernet or other means.

Since the timestamp of the roadside data is synchronized with UTC, a unified time axis is required when the roadside data and the vehicle-side data are fused and calculated. In this embodiment, the timestamp of the roadside data is adjusted based on the vehicle-side data. That is, the timestamp _Tr1 before the roadside data is updated is updated to _Tr2 , where Tr2 = Tr1 + △t.

The Δt sent by Pbox to the domain controller is used to normalize and compensate the timestamp of V2X data. Because when the domain controller synchronizes the Pbox, it can be considered that the domain controller's timer is synchronized with the Pbox's timer, and Δt is the difference between the Pbox's timer and the UTC time. It can be considered that Δt is also the difference between the domain controller's timer and the UTC time. Excluding the transmission delay of V2X data, it can be further considered that Δt is also the deviation between the domain controller's timer and the timestamp of V2X data.

For example, if the UTC time is 2024-5-28 10:30:00:111 milliseconds; the domain control time is 2024-5-28, 10:30:00:000 milliseconds, the Pbox time = domain control time; Pbox calculates Δt = 111 milliseconds based on its own time and UTC time; the Pbox positioning inertial navigation data timestamp is 2024-5-28, 10:30:00:000 milliseconds, and the vehicle-side sensor timestamp is 2024-5-28, 10:30:00:000 milliseconds; the V2X data timestamp is synchronized with UTC, which is 2024-5-28, 10:30:00:111 milliseconds; the V2X data enters the domain control, is normalized, and Δt is subtracted to get 2024-5-28, 10:30:00:000 milliseconds for data fusion.

In an exemplary embodiment, after updating the timestamp of when the sensor data in the roadside data is collected to a timestamp synchronized with the second synchronization time based on the second synchronization time, the method further includes:

S61, when the timestamp when the sensor data in the vehicle-side data is collected is updated to a timestamp synchronized with the second synchronization time, the vehicle environment data is determined based on the vehicle-side data after the updated timestamp and the road-side data after the updated timestamp, wherein the vehicle-side data includes the sensor data of the vehicle collected by the Pbox and the timestamp when the sensor data is collected, and the vehicle environment data is used to indicate the location of the vehicle.

Optionally, in this embodiment, in the scenario of vehicle-road collaboration, the vehicle environment data is determined based on the vehicle-side data after the update timestamp and the road-side data after the update timestamp, which means combining the data collected by the vehicle's own sensors (such as Pbox, on-board cameras, lidar, millimeter-wave radar, etc.) with the data collected by the roadside infrastructure (such as roadside cameras, sensors, communication units, etc.) to form a comprehensive and integrated traffic environment perception.

For example, in this embodiment, the position of the vehicle includes its relative position with other road elements. Based on the vehicle-side data after updating the timestamp (for example, the position data of the vehicle itself) and the road-side data after updating the timestamp (for example, the position data of other vehicles and pedestrians), the relative position of the vehicle itself and other vehicles or pedestrians on the same time base can be determined.

Through this embodiment, by fusing vehicle-side data and road-side data, the ability to perceive traffic conditions can be improved, the performance of the intelligent transportation system can be enhanced, and effective communication between vehicles, vehicles and infrastructure, vehicles and pedestrians, etc. can be achieved.

In this embodiment, a time synchronization method running on a vehicle is provided. FIG. 6 is a flow chart of a time synchronization method according to an embodiment of the present invention. As shown in FIG. 6 , the flow chart includes the following steps:

Step S602, within a specified time period after the domain controller is powered on, a time acquisition request is sent to the positioning box Pbox, wherein the domain controller is used to synchronize the time of at least one slave device, and the at least one slave device includes the Pbox;

Step S604, obtaining the network time sent by the Pbox in response to the time acquisition request, wherein the network time is the time obtained by the Pbox through the mobile communication network;

Step S606: based on the network time, update the local time of the domain controller to the first synchronization time, and control the first timer in the domain controller to continue timing from the first synchronization time, wherein the local time of the domain controller is the time provided by the first timer in the domain controller;

Step S608: Send a first synchronization time to the Pbox, wherein the first synchronization time is used to update the local time of the Pbox to a second synchronization time, wherein the first synchronization time is synchronized with the second synchronization time.

For the domain controller, a time acquisition request can be sent to the Pbox within a specified time period at the beginning of power-on. Similar to the aforementioned embodiment, the time acquisition request is used to obtain the network time from the Pbox as the starting time of the local time of the domain controller. The domain controller is used to synchronize the time of at least one slave device, and the at least one slave device includes the Pbox.

When the network signal is good, the domain controller can obtain the network time sent by the Pbox in response to the time acquisition request, wherein the network time is the time obtained by the Pbox through the mobile communication network.

The domain controller can update the local time of the domain controller to the first synchronization time based on the acquired network time, and control the first timer in the domain controller to continue timing from the first synchronization time, wherein the local time of the domain controller is the time provided by the first timer in the domain controller.

The domain controller periodically sends a first synchronization time to the Pbox, wherein the first synchronization time is used to update the local time of the Pbox to a second synchronization time, wherein the first synchronization time is synchronized with the second synchronization time.

Optionally, the local time of the Pbox may be the time provided by a second timer in the Pbox.

Through this embodiment, the problem that the Pbox cannot synchronize time during cold start can be solved; the problem that the autonomous driving vehicle cannot obtain time when starting in the basement can be solved; the domain controller, as the master device of the time synchronization system, is reliable, stable, and does not jump; and the timing system has no PPS signal line, which can avoid interference and jumps, greatly improving the stability of the time synchronization of the autonomous driving system.

Through the description of the above implementation methods, those skilled in the art can clearly understand that the method according to the above embodiment can be implemented by means of software plus a necessary general hardware platform, and of course can also be implemented by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium (such as ROM/RAM, a magnetic disk, or an optical disk), and includes a number of instructions for a terminal device (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods of various embodiments of the present invention.

In this embodiment, a time synchronization device is also provided, which is used to implement the above-mentioned embodiments and preferred implementation modes, and the descriptions that have been made will not be repeated. As used below, the term "module" can implement a combination of software and/or hardware of a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

FIG. 7 is a structural block diagram of a time synchronization device according to an embodiment of the present invention. As shown in FIG. 7 , the device includes:

The first execution unit 702 is used to obtain network time through the mobile communication network in response to a received time acquisition request within a specified time period after the domain controller is powered on, and send the network time to the domain controller, wherein the time acquisition request is a request sent by the domain controller to the positioning box Pbox;

A first acquisition unit 704 is configured to acquire a first synchronization time sent by a domain controller, wherein the domain controller is configured to perform time synchronization on at least one slave device, wherein the at least one slave device includes a Pbox, and the first synchronization time is a time obtained by updating a local time of the domain controller using the network time as a start time, and the local time of the domain controller is a time provided by a first timer in the domain controller;

The first updating unit 706 is used to update the local time of the Pbox to the second synchronization time based on the first synchronization time, wherein the first synchronization time is synchronized with the second synchronization time.

It should be noted that the first execution unit 702 in this embodiment can be used to execute the above step S202, the first acquisition unit 704 in this embodiment can be used to execute the above step S204, and the first update unit 706 in this embodiment can be used to execute the above step S206.

Through the embodiment of the present invention, within a specified time period after the domain controller is powered on, in response to the received time acquisition request, the network time is acquired through the mobile communication network, and the network time is sent to the domain controller, wherein the time acquisition request is a request sent by the domain controller to the positioning box Pbox; the first synchronization time sent by the domain controller is acquired, wherein the domain controller is used to synchronize the time of at least one slave device, and the at least one slave device includes Pbox, and the first synchronization time is the time obtained by updating the local time of the domain controller with the network time as the starting time, and the local time of the domain controller is the time provided by the first timer in the domain controller; based on the first synchronization time, the local time of the Pbox is updated to the second synchronization time, wherein the first synchronization time is synchronized with the second synchronization time. The problem that the time synchronization method in the related art cannot synchronize the time of the vehicle in the scenario without satellite signals is solved.

In an exemplary embodiment, the first execution unit includes:

The acquisition module is used to acquire the network time through the mobile communication network in response to a received time acquisition request when the Pbox cannot detect a satellite signal.

In an exemplary embodiment, the first updating unit includes:

The first execution module is used to update the current time provided by the second timer in the Pbox to the second synchronization time when the local time of the Pbox is the time provided by the second timer in the Pbox, and control the second timer to continue timing from the second synchronization time, wherein the second synchronization time is equal to the time obtained by adding the first synchronization time to the first time difference, the first time difference is the difference obtained by subtracting the first time from the current time provided by the second timer, and the first time is the time of the second timer when the Pbox receives the first synchronization time.

In an exemplary embodiment, the above device further comprises:

The second updating unit is used to update the local time of the Pbox to the second synchronization time based on the first synchronization time, and then update the timestamp when the sensor data in the vehicle-side data is collected to a timestamp synchronized with the second synchronization time based on the second synchronization time, wherein the vehicle-side data includes the sensor data of the vehicle collected by the Pbox and the timestamp when the sensor data is collected.

In an exemplary embodiment, the above device further comprises:

The third updating unit is used for updating the local time of the Pbox to the second synchronization time based on the first synchronization time, and then, when the domain controller receives the roadside data, updating the timestamp when the sensor data in the roadside data is collected to a timestamp synchronized with the second synchronization time based on the second synchronization time, wherein the roadside data includes sensor data collected by equipment outside the vehicle and the timestamp when the sensor data is collected.

In an exemplary embodiment, the third updating unit includes:

The second execution module is used for adding the timestamp when the sensor data in the roadside data is collected to the third time difference to obtain a timestamp synchronized with the second synchronization time when the Pbox receives the world standard time through the global navigation satellite system GNSS antenna, wherein the timestamp when the sensor data in the roadside data is collected is a timestamp determined based on the world standard time, and the third time difference is the difference obtained by subtracting the world standard time from the time provided by the second timer in the Pbox when the Pbox receives the world standard time through the GNSS antenna.

In an exemplary embodiment, the above device further comprises:

A determination unit is used to update the timestamp when the sensor data in the roadside data is collected to a timestamp synchronized with the second synchronization time based on the second synchronization time, and determine the vehicle environment data based on the vehicle-side data after the updated timestamp and the roadside data after the updated timestamp, after the timestamp when the sensor data in the vehicle-side data is collected is updated to a timestamp synchronized with the second synchronization time, wherein the vehicle-side data includes the sensor data of the vehicle collected by the Pbox and the timestamp when the sensor data is collected, and the vehicle environment data is used to indicate the location of the vehicle.

FIG8 is a structural block diagram of a time synchronization device according to an embodiment of the present invention. As shown in FIG8 , the device includes:

A first sending unit 802 is used to send a time acquisition request to the positioning box Pbox within a specified time period after the domain controller is powered on, wherein the domain controller is used to perform time synchronization on at least one slave device, and the at least one slave device includes the Pbox;

A second acquisition unit 804 is used to acquire the network time sent by the Pbox in response to the time acquisition request, wherein the network time is the time acquired by the Pbox through the mobile communication network;

The second execution unit 806 is used to update the local time of the domain controller to the first synchronization time based on the network time, and control the first timer in the domain controller to continue timing from the first synchronization time, wherein the local time of the domain controller is the time provided by the first timer in the domain controller;

The second sending unit 808 is used to send a first synchronization time to the Pbox, wherein the first synchronization time is used to update the local time of the Pbox to a second synchronization time, wherein the first synchronization time is synchronized with the second synchronization time.

It should be noted that the first sending unit 802 in this embodiment can be used to execute the above step S602, the second acquisition unit 804 in this embodiment can be used to execute the above step S604, the second execution unit 806 in this embodiment can be used to execute the above step S606; the second sending unit 808 in this embodiment can be used to execute the above step S608.

An embodiment of the present invention further provides a computer-readable storage medium, in which a computer program is stored, wherein the computer program is configured to execute the steps of any of the above method embodiments when running.

In an exemplary embodiment, the computer-readable storage medium may include, but is not limited to, various media that can store computer programs, such as a USB flash drive, a read-only memory (ROM), a random access memory (RAM), a mobile hard disk, a magnetic disk or an optical disk.

An embodiment of the present invention further provides an electronic device, including a memory and a processor, wherein a computer program is stored in the memory, and the processor is configured to run the computer program to execute the steps in any one of the above method embodiments.

In an exemplary embodiment, the electronic device may further include a transmission device and an input/output device, wherein the transmission device is connected to the processor, and the input/output device is connected to the processor.

For specific examples in this embodiment, reference may be made to the examples described in the above embodiments and exemplary implementation modes, and this embodiment will not be described in detail herein.

An embodiment of the present invention further provides a computer program product, which includes a computer program. When the computer program is executed by a processor, the steps in any one of the above method embodiments are implemented.

An embodiment of the present invention further provides another computer program product, including a non-volatile computer-readable storage medium, wherein the non-volatile computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps in any of the above method embodiments are implemented.

An embodiment of the present invention also provides a computer program, which includes computer instructions stored in a computer-readable storage medium; a processor of a computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device performs the steps in any one of the above-mentioned method embodiments.

Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general computing device, they can be concentrated on a single computing device, or distributed on a network composed of multiple computing devices, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, and in some cases, the steps shown or described can be executed in a different order than here, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. Thus, the present invention is not limited to any specific combination of hardware and software.

The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the principles of the present invention shall be included in the protection scope of the present invention.

Claims (10)

1. A time synchronization method, comprising: In a specified time period after the domain controller is powered on, in response to a received time acquisition request, obtain network time through a mobile communication network, and send the network time to the domain controller, wherein the time acquisition request is a request sent by the domain controller to the positioning box Pbox; Obtaining a first synchronization time sent by the domain controller, wherein the domain controller is used to perform time synchronization on at least one slave device, the at least one slave device includes the Pbox, the first synchronization time is a time obtained by updating the local time of the domain controller using the network time as the starting time, and the local time of the domain controller is a time provided by a first timer in the domain controller; Based on the first synchronization time, the local time of the Pbox is updated to a second synchronization time, wherein the first synchronization time is synchronized with the second synchronization time. 2. The method according to claim 1, characterized in that, in response to the received time acquisition request, acquiring the network time through the mobile communication network comprises: In the case that the Pbox cannot detect a satellite signal, the network time is acquired through the mobile communication network in response to the received time acquisition request. 3. The method according to claim 1, characterized in that the updating of the local time of the Pbox to the second synchronization time based on the first synchronization time comprises: In a case where the local time of the Pbox is the time provided by the second timer in the Pbox, the current time provided by the second timer in the Pbox is updated to the second synchronization time, and the second timer is controlled to continue timing from the second synchronization time, wherein the second synchronization time is equal to the time obtained by adding the first synchronization time to a first time difference, the first time difference is the difference obtained by subtracting the first time from the current time provided by the second timer, and the first time is the time of the second timer when the Pbox receives the first synchronization time. 4. The method according to claim 1, characterized in that after the local time of the Pbox is updated to the second synchronization time based on the first synchronization time, the method further comprises: Based on the second synchronization time, the timestamp when the sensor data in the vehicle-side data is collected is updated to a timestamp synchronized with the second synchronization time, wherein the vehicle-side data includes the sensor data of the vehicle collected by the Pbox and the timestamp when the sensor data is collected. 5. The method according to any one of claims 1 to 4, characterized in that after updating the local time of the Pbox to the second synchronization time based on the first synchronization time, the method further comprises: When the domain controller receives the roadside data, based on the second synchronization time, the timestamp when the sensor data in the roadside data is collected is updated to a timestamp synchronized with the second synchronization time, wherein the roadside data includes the sensor data collected by a device outside the vehicle and the timestamp when the sensor data is collected. 6. The method according to claim 5, characterized in that the step of updating the timestamp of when the sensor data in the roadside data is collected to a timestamp synchronized with the second synchronization time based on the second synchronization time comprises: In a case where the Pbox receives the world standard time through the global navigation satellite system GNSS antenna, the timestamp when the sensor data in the roadside data is collected is added to the third time difference to obtain a timestamp synchronized with the second synchronization time, wherein the timestamp when the sensor data in the roadside data is collected is a timestamp determined based on the world standard time, and the third time difference is the difference obtained by subtracting the world standard time from the time provided by the second timer in the Pbox when the Pbox receives the world standard time through the GNSS antenna. 7. The method according to claim 5, characterized in that after the timestamp when the sensor data in the roadside data is collected is updated to a timestamp synchronized with the second synchronization time based on the second synchronization time, the method further comprises: When the timestamp of the sensor data in the vehicle-side data when it is collected is updated to a timestamp synchronized with the second synchronization time, the vehicle environment data is determined based on the vehicle-side data after the updated timestamp and the road-side data after the updated timestamp, wherein the vehicle-side data includes the sensor data of the vehicle collected by the Pbox and the timestamp when the sensor data is collected, and the vehicle environment data is used to indicate the location of the vehicle. 8. A time synchronization method, comprising: Sending a time acquisition request to a positioning box Pbox within a specified time period after the domain controller is powered on, wherein the domain controller is used to synchronize the time of at least one slave device, and the at least one slave device includes the Pbox; Acquire the network time sent by the Pbox in response to the time acquisition request, wherein the network time is the time acquired by the Pbox through the mobile communication network; Based on the network time, updating the local time of the domain controller to a first synchronization time, and controlling a first timer in the domain controller to continue timing from the first synchronization time, wherein the local time of the domain controller is the time provided by the first timer in the domain controller; The first synchronization time is sent to the Pbox, wherein the first synchronization time is used to update the local time of the Pbox to a second synchronization time, wherein the first synchronization time is synchronized with the second synchronization time. 9. A computer-readable storage medium, characterized in that a computer program is stored in the computer-readable storage medium, wherein when the computer program is executed by a processor, the steps of the method described in any one of claims 1 to 8 are implemented. 10. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the method described in any one of claims 1 to 8 when executing the computer program.