CN-121977585-A - Navigation system time synchronization method, device, equipment and storage medium

CN121977585ACN 121977585 ACN121977585 ACN 121977585ACN-121977585-A

Abstract

The application discloses a navigation system time synchronization method, a device, equipment and a storage medium, which relate to the technical field of navigation and comprise the steps of determining a local clock initial step length pre-estimated value according to a plurality of continuous second pulse signals of a global navigation satellite system when satellite signal quality of the global navigation satellite system is good, determining a current local clock step length measured value according to a last second pulse signal and a current second pulse signal, acquiring satellite interference conditions, determining whether the satellite signal quality and the satellite interference conditions meet satellite use conditions or not, and determining a current local clock step length pre-estimated value and a current local clock absolute moment based on the satellite use conditions, the historical local clock step length pre-estimated value and the current local clock step length measured value to finish the navigation system time synchronization of a plurality of sensors. The scheme can keep high precision of time synchronization of the multi-sensor data.

Inventors

PAN CHAO
LU YU

Assignees

湖北经济学院

Dates

Publication Date: 20260505
Application Date: 20260409

Claims (10)

1. A navigation system time synchronization method, characterized in that the navigation system time synchronization method comprises: When the satellite signal quality of the global navigation satellite system is good, determining a local clock initial step size estimated value according to a plurality of continuous second pulse signals of the global navigation satellite system, and taking the local clock initial step size estimated value as a historical local clock step size estimated value; determining a current local clock step measurement value according to the last second pulse signal and the current second pulse signal; Acquiring satellite interference conditions, and determining whether the satellite signal quality and the satellite interference conditions meet satellite use conditions; determining a current local clock step size estimated value and a current local clock absolute time based on the satellite use condition coincidence condition, the historical local clock step size estimated value and the current local clock step size measured value; And finishing the time synchronization of the navigation system of the multiple sensors based on the current local clock step length predicted value and the current local clock absolute time.
2. The method of claim 1, wherein the step of performing navigation system time synchronization for multiple sensors based on the current local clock step size estimate and the current local clock absolute time comprises: Under the condition that satellite signal quality is good, acquiring a local clock error; Fitting a clock phase, a clock frequency and a clock frequency drift rate based on the local clock error; When the duration which does not meet the satellite use condition reaches the preset satellite unlocking duration, compensating the absolute moment of the current local clock based on the clock phase, the clock frequency and the clock frequency drift rate to obtain the compensated absolute moment of the current local clock; And completing the time synchronization of the navigation system of the multiple sensors based on the current local clock step length predicted value and the compensated absolute time of the current local clock.
3. The method of claim 1, wherein the step of determining the initial step size estimate of the local clock from a plurality of consecutive pulse-per-second signals of the global navigation satellite system when the satellite signal quality of the global navigation satellite system is good, further comprises: Acquiring a satellite positioning state, the number of positioning satellites and a position accuracy attenuation factor of a global navigation satellite system, and determining satellite signal quality according to the satellite positioning state, the number of positioning satellites and the position accuracy attenuation factor; before the step of obtaining the satellite interference condition, the method further comprises the following steps: and determining satellite interference conditions of the global navigation satellite system according to the current local clock step measurement value and the historical local clock step predicted value.
4. The method of claim 1, wherein the step of determining a current local clock step estimate and a current local clock absolute time based on compliance with the satellite usage conditions, the historical local clock step estimate, and the current local clock step measure comprises: When the satellite signal quality and the satellite interference condition meet the satellite use condition, determining a current local clock step length predicted value based on a predicted step length weight, a measured step length weight, the historical local clock step length predicted value and the current local clock step length measured value, and determining the absolute time of a local clock according to the time information of the global navigation satellite system; and when the satellite signal quality or the satellite interference condition does not accord with the satellite use condition, determining the historical local clock step length predicted value as a current local clock step length predicted value, and updating the absolute moment of the local clock based on the current local clock step length predicted value and the current local clock step length measured value.
5. The method of claim 1, wherein the step of performing navigation system time synchronization for multiple sensors based on the current local clock step size estimate and the current local clock absolute time comprises: Maintaining a sampling time base standard based on the current local clock step size pre-estimated value and the current local clock absolute time; Clock frequency division is carried out based on the sampling time base standard, so that sampling trigger clocks of a plurality of sensors are obtained; controlling the plurality of sensors to acquire corresponding sensor data according to the sampling trigger clock; And calculating the sampling time information corresponding to each sampling point of the plurality of sensors according to the sampling time base standard so as to store or navigate the sensor data and the sampling time information and complete the time synchronization of a navigation system of the plurality of sensors.
6. The method of claim 5, wherein said step of clock dividing based on said sample time base criteria to obtain sample trigger clocks for a plurality of sensors comprises: Performing clock frequency division based on the sampling time base standard to obtain initial sampling clock signals of a plurality of sensors; when the sensors request synchronous triggering, acquiring data output enabling signals, hardware connection state information and data transmission delay of the sensors; responding to the data output enabling signal to acquire data value rationality information; evaluating data validity according to the hardware connection state information and the data value rationality information; According to the data validity and the data transmission delay, carrying out phase adjustment on the initial sampling clock signal to obtain a calibration sampling clock signal; And carrying out dynamic clock resource allocation based on the preset sensor synchronization priority identification and the calibration sampling clock signal to obtain sampling trigger clocks of a plurality of sensors.
7. The method of claim 5, wherein the step of calculating the sampling time information corresponding to each sampling point of the plurality of sensors according to the sampling time base standard comprises: acquiring a whole second accumulated count value from the sampling time base standard; Acquiring local counting information of an inertial measurement unit at a sampling time, local counting information of a wheel speed meter at the sampling time and local counting information of a visual sensor at the sampling time based on the whole second accumulated count value and the multi-sensor sampling frequency configuration information; And obtaining sampling time information corresponding to each sampling point of the plurality of sensors according to the sampling time base standard, the local counting information of the inertial measurement unit at the sampling time, the local counting information of the wheel speed meter at the sampling time and the local counting information of the visual sensor at the sampling time.
8. A navigation system time synchronization device, the device comprising: The step estimation module is used for determining a local clock initial step pre-estimation value according to a plurality of continuous second pulse signals of the global navigation satellite system when the satellite signal quality of the global navigation satellite system is good, and taking the local clock initial step pre-estimation value as a historical local clock step pre-estimation value; The data processing module is used for determining a current local clock step length measurement value according to the last second pulse signal and the current second pulse signal; The condition judging module is used for acquiring satellite interference conditions and determining whether the satellite signal quality and the satellite interference conditions accord with satellite use conditions or not; The data processing module is further configured to determine a current local clock step size estimated value and a current local clock absolute time based on the satellite usage condition compliance, the historical local clock step size estimated value, and the current local clock step size measured value; And the time synchronization module is used for completing the time synchronization of the navigation system of the multiple sensors based on the current local clock step length predicted value and the current local clock absolute time.
9. A navigation system time synchronization device, characterized in that the device comprises a memory, a processor and a computer program stored on the memory and executable on the processor, the computer program being configured to implement the steps of the navigation system time synchronization method according to any one of claims 1 to 7.
10. A storage medium, characterized in that the storage medium is a computer-readable storage medium, on which a computer program is stored, which computer program, when being executed by a processor, realizes the steps of the navigation system time synchronization method according to any one of claims 1 to 7.

Description

Navigation system time synchronization method, device, equipment and storage medium Technical Field The present application relates to the field of navigation technologies, and in particular, to a navigation system time synchronization method, apparatus, device, and storage medium. Background In the field of automatic driving or unmanned aerial vehicle navigation, a plurality of sensors such as a satellite navigation module, an inertial measurement unit, a vision sensor (a monocular camera, a binocular camera), a laser radar, a wheel speed meter, a magnetometer and the like can be used, and the problems that the time systems of the sensors are inconsistent, even the sensors have no independent time system and the like exist in the application process. In addition, the sampling frequency, the data transmission rate and the like of various sensors are different, and the absolute time precision of the acquisition system is ensured to be within a certain error range, and the ultra-low time delay synchronous acquisition of the multi-sensor data can be carried out. The prior proposal takes a second pulse signal (1 Pulse Per Second,1PPS) as an interrupt signal, adopts a central processing unit (Central Processing Unit, CPU) timer to generate a sampling clock synchronous with 1PPS, realizes the synchronization of data acquisition and 1PPS, always needs the participation of the CPU in the synchronization process, the CPU controls data acquisition, so that the task amount of the CPU is increased, and when the satellite signal of the global navigation satellite system (Global Navigation SATELLITE SYSTEM, GNSS) is out of lock for a long time, the precision of 1PPS pulse is attenuated, and the time synchronization precision and reliability of the multi-sensor data are directly reduced. Therefore, how to maintain high accuracy of multi-sensor data time synchronization becomes a problem to be solved. The foregoing is provided merely for the purpose of facilitating understanding of the technical solutions of the present application and is not intended to represent an admission that the foregoing is prior art. Disclosure of Invention The application mainly aims to provide a navigation system time synchronization method, a navigation system time synchronization device, navigation system time synchronization equipment and a storage medium, and aims to solve the technical problem of how to keep high precision of multi-sensor data time synchronization. In order to achieve the above object, the present application provides a navigation system time synchronization method, which includes: When the satellite signal quality of the global navigation satellite system is good, determining a local clock initial step size estimated value according to a plurality of continuous second pulse signals of the global navigation satellite system, and taking the local clock initial step size estimated value as a historical local clock step size estimated value; determining a current local clock step measurement value according to the last second pulse signal and the current second pulse signal; Acquiring satellite interference conditions, and determining whether the satellite signal quality and the satellite interference conditions meet satellite use conditions; determining a current local clock step size estimated value and a current local clock absolute time based on the satellite use condition coincidence condition, the historical local clock step size estimated value and the current local clock step size measured value; And finishing the time synchronization of the navigation system of the multiple sensors based on the current local clock step length predicted value and the current local clock absolute time. In an embodiment, the step of performing time synchronization of the navigation system of the multi-sensor based on the current local clock step size predicted value and the current local clock absolute time comprises: Under the condition that satellite signal quality is good, acquiring a local clock error; Fitting a clock phase, a clock frequency and a clock frequency drift rate based on the local clock error; When the duration which does not meet the satellite use condition reaches the preset satellite unlocking duration, compensating the absolute moment of the current local clock based on the clock phase, the clock frequency and the clock frequency drift rate to obtain the compensated absolute moment of the current local clock; And completing the time synchronization of the navigation system of the multiple sensors based on the current local clock step length predicted value and the compensated absolute time of the current local clock. In an embodiment, before the step of determining the initial step size predicted value of the local clock according to the plurality of continuous second pulse signals of the global navigation satellite system when the satellite signal quality of the global navigation satellite system is good, the method