Vehicle positioning system based on vehicle CAN bus and satellite positioningTechnical Field
The invention belongs to the technical field of positioning, and particularly relates to a vehicle positioning system based on a vehicle CAN bus and satellite positioning.
Background
The location information of the vehicle is an important element for realizing intelligent traffic, such as navigation, traffic control, charging, etc. Along with the continuous development of the positioning technology, the requirements on positioning precision are higher and higher, and the positioning result needs to be distinguished into a main road, an auxiliary road, a bridge or a bridge under. Satellites and base stations have become fundamental technical means for positioning vehicles, but because the road environment where vehicles travel is complex and changeable, uninterrupted accurate positioning cannot be realized when no signal is covered or blocked and reflected, and other positioning technologies must be assisted.
In order to solve the technical problems, the invention provides a vehicle positioning system based on a vehicle CAN bus and satellite positioning. The system realizes accurate positioning by a specific algorithm for the auxiliary method of GPS positioning under the conditions. Providing more accurate data support for customers.
Disclosure of Invention
In order to overcome the problems in the prior art, the vehicle positioning system based on the vehicle CAN bus and satellite positioning provided by the invention comprises: the system comprises a CAN bus, a CAN data analysis device, a satellite positioning system and a vehicle-mounted terminal, wherein the CAN bus, the CAN data analysis device, the satellite positioning system and the vehicle-mounted terminal are arranged in a vehicle;
the CAN bus is connected with the input end of the CAN data analysis device through an OBD interface, and the vehicle running parameters obtained through analysis by the CAN data analysis device are input into the vehicle-mounted terminal through an output end;
the vehicle-mounted terminal comprises:
the online positioning data analysis module is used for reading online positioning data of the satellite positioning system, wherein the online positioning data comprises satellite positioning data, a time stamp and signal strength;
a vehicle data reading module that reads the vehicle running parameters;
the off-line positioning data analysis module is used in the vehicle positioning system based on the vehicle CAN bus and satellite positioning, and uses off-line positioning data to correct and modify on-line positioning data to generate final vehicle positioning data.
In the vehicle positioning system based on the vehicle CAN bus and satellite positioning, the vehicle running parameters read by the vehicle data reading module from the CAN data analysis device comprise: the instantaneous speed of the vehicle running, the steering wheel deflection angle and the time stamp of the acquired data.
In the vehicle positioning system based on the vehicle CAN bus and satellite positioning, the off-line positioning data analysis module calculates the average value of the instantaneous speed of the vehicle at the current time stamp and the instantaneous speed of the latter time stamp and the time interval between the time stamps, and calculates the distance offset of the vehicle in the time interval.
In the vehicle positioning system based on the vehicle CAN bus and satellite positioning, the off-line positioning data analysis module calculates the deflection angle of the steering wheel in the front and rear time stamps, converts the deflection angle into the steering angle of the steering wheel of the vehicle, and generates the displacement offset of the vehicle in the same time interval by combining the distance offset and the steering angle in the same time interval.
In the vehicle positioning system based on the vehicle CAN bus and satellite positioning, the vehicle data reading module further reads the maximum deflection angle of the steering wheel and the maximum steering angle of the steering wheel of the vehicle; the off-line positioning data analysis module converts the steering angle of the steering wheel of the vehicle according to the same proportion of the deflection angle and the maximum deflection angle.
In the vehicle positioning system based on the vehicle CAN bus and satellite positioning, the online positioning data analysis module is internally configured with: receiving or pre-storing geographic road condition information of an area where a vehicle is located; the geographical road condition information includes the road conditions of the drivable roads and the roads.
In the vehicle positioning system based on the vehicle CAN bus and satellite positioning, the positioning correction module is configured to: in the vehicle positioning system based on the vehicle CAN bus and satellite positioning, which is provided by the invention, the off-line stage is defined between two time stamps, and the off-line positioning data is used for correcting the on-line positioning data in the off-line stage to generate final vehicle positioning data.
In the vehicle positioning system based on the vehicle CAN bus and satellite positioning, the positioning correction module is configured to: in the vehicle positioning system based on the vehicle CAN bus and satellite positioning, which is provided by the invention, the off-line stage is defined between two time stamps, and the off-line positioning data is used for modifying the on-line positioning data in the off-line stage to generate final vehicle positioning data.
In the vehicle positioning system based on the vehicle CAN bus and satellite positioning, the vehicle-mounted terminal further comprises a display device for displaying the geographic position of the vehicle in real time according to final vehicle positioning data.
Compared with the prior art, the invention has the beneficial effects that: the vehicle positioning system based on the CAN bus and the satellite positioning, provided by the invention, is integrated on the vehicle-mounted terminal by utilizing the speed and steering wheel deflection information carried on the automobile CAN bus, so that the calculation of the running track of the vehicle is realized, the equipment cost is reduced, and the accuracy of auxiliary positioning is also increased.
Drawings
Fig. 1 shows a schematic structure of a vehicle positioning system based on a vehicle CAN bus and satellite positioning according to the present invention.
In FIG. 1, a 1-CAN bus, a 2-CAN data analysis device, a 3-vehicle terminal, a 4-satellite positioning system, a 31-on-line positioning data analysis module, a 32-vehicle data reading module, a 33-off-line positioning data analysis module and a 34-positioning correction module are arranged.
Detailed Description
The vehicle positioning system based on the vehicle CAN bus and satellite positioning according to the present invention will be described in more detail with reference to the drawings, wherein preferred embodiments of the present invention are shown, it being understood that the present invention described herein CAN be modified by those skilled in the art, while still achieving the advantageous effects of the present invention. Accordingly, the following description is to be construed as broadly known to those skilled in the art and not as limiting the invention.
As shown in fig. 1, in a preferred embodiment of the present invention, it includes: a CAN bus 1, a CAN data analysis device 2, a satellite positioning system 4 and a vehicle-mounted terminal 3 which are arranged in a vehicle; the CAN bus 1 is connected with the input end of the CAN data analysis device 2 through an OBD interface, and the vehicle running parameters obtained by analysis of the CAN data analysis device 2 are input into the vehicle-mounted terminal 3 through an output end; the in-vehicle terminal 3 includes: an online positioning data analysis module 31 for reading online positioning data of the satellite positioning system 4, the online positioning data including satellite positioning data, a time stamp, and signal strength; a vehicle data reading module 32 that reads the vehicle running parameters; an offline positioning data analysis module 32, which is used in the preferred embodiment of the present invention, uses the offline positioning data to modify and modify the online positioning data to generate final vehicle positioning data.
In a preferred embodiment of the present invention, the vehicle driving parameters read by the vehicle data reading module 32 from the CAN data analysis device 2 include: the instantaneous speed of the vehicle running, the steering wheel deflection angle and the time stamp of the acquired data.
In a preferred embodiment of the present invention, the offline positioning data analysis module 32 calculates the time interval between the average value of the instantaneous speed of the vehicle at the current time stamp and the instantaneous speed of the subsequent time stamp, and calculates the distance offset of the vehicle occurring in the time interval.
In a preferred embodiment of the present invention, the off-line positioning data analysis module 32 calculates the steering angle of the steering wheel in the front and rear time stamps, converts the steering angle into the steering angle of the steering wheel of the vehicle, and generates the displacement offset of the vehicle in the same time interval by combining the distance offset and the steering angle in the same time interval.
In a preferred embodiment of the present invention, the vehicle data reading module 32 further reads the maximum steering angle of the steering wheel and the maximum steering angle of the steering wheel of the vehicle; the off-line positioning data analysis module 32 scales steering angles of the vehicle steering wheels in the same proportion to the deflection angle and the maximum deflection angle.
In a preferred embodiment of the present invention, the online location data analysis module 31 is configured to: receiving or pre-storing geographic road condition information of an area where a vehicle is located; the geographical road condition information includes the road conditions of the drivable roads and the roads.
In a preferred embodiment of the present invention, the positioning correction module 34 is configured to: the location correction module 34 defines an off-line phase between the two time stamps, and corrects the on-line location data using the off-line location data during the off-line phase to generate final vehicle location data.
In a preferred embodiment of the present invention, the positioning correction module 34 is configured to: the location correction module 34, in a preferred embodiment of the present invention, defines the time between two timestamps as an offline phase in which off-line location data is used to modify on-line location data to generate final vehicle location data.
In a preferred embodiment of the present invention, the vehicle-mounted terminal 3 further includes a display device, configured to display the geographic location of the vehicle in real time according to the final vehicle positioning data.
The foregoing is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any person skilled in the art will make any equivalent substitution or modification to the technical solution and technical content disclosed in the invention without departing from the scope of the technical solution of the invention, and the technical solution of the invention is not departing from the scope of the invention.