WO2021037038A1 - 定位方法与系统、电子设备、车辆与存储介质 - Google Patents

定位方法与系统、电子设备、车辆与存储介质 Download PDF

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Publication number
WO2021037038A1
WO2021037038A1 PCT/CN2020/111222 CN2020111222W WO2021037038A1 WO 2021037038 A1 WO2021037038 A1 WO 2021037038A1 CN 2020111222 W CN2020111222 W CN 2020111222W WO 2021037038 A1 WO2021037038 A1 WO 2021037038A1
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Prior art keywords
vehicle
speed
electronic device
preset
satellite
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PCT/CN2020/111222
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English (en)
French (fr)
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崔昌华
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华为技术有限公司
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Publication of WO2021037038A1 publication Critical patent/WO2021037038A1/zh

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C21/00—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00
    • G01C21/26—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 specially adapted for navigation in a road network
    • G01C21/28—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 specially adapted for navigation in a road network with correlation of data from several navigational instruments
    • G01C21/30—Map- or contour-matching
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C21/00—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00
    • G01C21/26—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 specially adapted for navigation in a road network
    • G01C21/34—Route searching; Route guidance
    • G01C21/3407—Route searching; Route guidance specially adapted for specific applications
    • G01C21/343—Calculating itineraries, i.e. routes leading from a starting point to a series of categorical destinations using a global route restraint, round trips, touristic trips
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/38—Determining a navigation solution using signals transmitted by a satellite radio beacon positioning system
    • G01S19/39—Determining a navigation solution using signals transmitted by a satellite radio beacon positioning system the satellite radio beacon positioning system transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/42—Determining position

Definitions

  • This application relates to the field of intelligent transportation technology, and in particular to a positioning method and system, electronic equipment, vehicles, and storage media.
  • DR dead reckoning
  • the DR calculation is to calculate the current position based on the previous position. Specifically, the DR calculation is to obtain the displacement and heading of the vehicle from the previous position based on the vehicle speed and the angular velocity of the vehicle, and combine the previous position to calculate the current position of the vehicle of.
  • the vehicle speed often has errors with the actual speed of the vehicle due to tire wear, air pressure changes, temperature changes, etc. This will further cause errors between the vehicle position estimated by DR and the actual vehicle position, and these position errors will continue to accumulate. , And continue to increase with the increase in mileage.
  • This application provides a positioning method and system, electronic equipment, vehicle, and storage medium, in order to reduce the accumulated mileage error of DR calculation and improve the accuracy of the DR calculation result.
  • this application provides a positioning method, including: when the vehicle is driving in a first environment, displaying the first vehicle position positioned by a satellite positioning system, and the satellite signal quality of the first environment meets the preset quality requirements When the vehicle is driving in the second environment, the second vehicle position is displayed, and the satellite signal quality of the second environment does not meet the preset quality requirements; wherein, the second vehicle position is the use of the first vehicle
  • the first vehicle speed is obtained by using the satellite positioning position and the dead reckoning position to correct the second vehicle speed
  • the second vehicle speed is the speed obtained during the driving of the vehicle.
  • the satellite positioning data is used to locate and navigate the user; when the vehicle is driving in the second environment with poor satellite signal, the DR calculation is used to locate
  • the vehicle position and in the embodiment of the present application, the vehicle position is estimated by the corrected vehicle speed, which is beneficial to reduce the accumulated mileage error caused by the vehicle speed and improve the accuracy of the DR estimation result.
  • the first vehicle speed is obtained by correcting the second vehicle speed using a speed compensation factor, and the speed compensation factor is based on the satellite positioning position and the navigation The position is obtained from the estimated position.
  • the correction result with a smaller error is also beneficial to reduce the error of the DR estimation result.
  • the speed compensation factor is obtained according to the satellite positioning position and the dead reckoning position when a preset correction condition is satisfied.
  • the correction condition at least includes: the quality of the satellite signal meets the preset quality requirement.
  • the preset quality requirements include: the satellite is in an effective positioning state; the horizontal accuracy factor of the satellite is less than or equal to the preset accuracy threshold; the number of satellites in the effective positioning state is greater than or equal to the preset first number threshold; signal strength The total number of satellites greater than or equal to the preset intensity threshold is greater than or equal to the preset second number threshold.
  • the quality of the satellite signal can meet the preset quality requirement in two ways: the first is that the satellite signal meets the preset continuous duration range. The preset quality requirements; at this time, the satellite signal quality is better and relatively stable, which is beneficial to obtaining more accurate satellite positioning data.
  • the second method is that the satellite signal meets the preset quality requirements instantaneously; at this time, the satellite signal is better for a short time and can also achieve satellite positioning, but compared to the previous method, the satellite signal covered by this method The better quality range is wider, but the satellite signal may be unstable. In this way, the requirements for better satellite signal quality can be adjusted through preset quality requirements, and adjustments to correction conditions can also be achieved.
  • the correction condition further includes at least one of the following: starting from the starting point of the dead reckoning, the mileage of the vehicle reaches a preset distance threshold; The mileage difference between the dead reckoning position and the satellite positioning position is greater than a preset error threshold; starting from the starting point estimated by the dead reckoning, the vehicle satisfies a preset straight forward condition.
  • the straight driving condition includes: starting from the starting point, the change of the heading angle of the vehicle is less than or equal to a preset angle; or, the vehicle driving one-way on a straight road starting from the starting point. In this way, frequent correction of vehicle speed can be avoided, which is beneficial to reduce the consumption of computing resources; and the straight-going conditions can also ensure to a certain extent that this solution can achieve a better DR estimation accuracy.
  • the mileage difference between the satellite positioning position and the dead reckoning position can be obtained; wherein the satellite positioning position corresponds to the dead reckoning position; and then, the mileage difference and the estimated dead reckoning position are obtained.
  • the ratio between the time lengths is used to obtain the speed compensation factor; wherein, the time-consuming time length is the length of time spent between the starting point of the dead reckoning and the dead reckoning position.
  • the speed compensation factor After the speed compensation factor is obtained, the sum of the speed compensation factor and the second vehicle speed is obtained to obtain the first vehicle speed; wherein, in the traveling direction of the vehicle, if the dead reckoning position falls In front of the satellite positioning position, the speed compensation factor is a negative value; or, in the driving direction of the vehicle, if the dead reckoning position falls behind the satellite positioning position, the speed compensation The factor is positive. In this way, through the correction of the speed compensation factor, the first vehicle speed used in the DR estimation can be made closer to the actual driving speed of the vehicle, which is beneficial to reduce errors and improve the accuracy of the estimation.
  • the dead reckoning position is calculated sequentially from the starting point; the starting point is obtained when a preset starting condition is satisfied. Satellite positioning location.
  • the starting point is the satellite positioning position obtained when a preset starting update condition is satisfied and the preset starting condition is satisfied.
  • the starting condition includes: satisfying at least one of the speed of the vehicle reaching a preset starting speed threshold, and the mileage of the vehicle reaching the preset starting mileage threshold; the quality of the satellite signal satisfies all The preset quality requirements; the navigation of the vehicle is stable.
  • the initial update condition includes at least one of the following: the number of dead reckoning calculations reaches a preset threshold of times; from the starting point, the mileage of the vehicle reaches a preset distance threshold; The mileage difference between the satellite positioning position and the dead reckoning position is greater than a preset error threshold; the variation of the heading angle of the vehicle is greater than the preset angle; and the preset correction condition is satisfied.
  • the heading angle is obtained by processing the angular velocity of the vehicle.
  • the second vehicle speed is collected by a first electronic device
  • the satellite positioning position is collected by a second electronic device
  • the angular velocity of the vehicle is collected by a third electronic device. It is collected, the first vehicle speed is corrected in the fourth electronic device, and the dead reckoning position is calculated in the fifth electronic device; the first electronic device, the second electronic device, and the first electronic device Among the three electronic devices, the fourth electronic device and the fifth electronic device, any two electronic devices are the same electronic device or different electronic devices.
  • the first electronic device, the second electronic device, the third electronic device, the fourth electronic device, and the fifth electronic device are all equipped with In the vehicle. At this time, there is no need to communicate with external devices, and the solution can be implemented directly in the vehicle.
  • some of the first electronic device, the second electronic device, the third electronic device, the fourth electronic device, and the fifth electronic device The electronic equipment is mounted on the vehicle, and some of the electronic equipment is mounted on a mobile device; wherein, some of the electronic equipment mounted on the vehicle and some of the electronic equipment mounted on the mobile device are communicatively connected.
  • the number of the movable device is at least one. This can satisfy the situation that the user sits in the car and uses a mobile device such as a mobile phone to perform positioning and navigation, and can adapt to a variety of application scenarios of the user with high flexibility.
  • the first electronic device is a speed acquisition device, the vehicle bus or a vehicle speedometer; the second electronic device is a satellite signal receiving device; the third The electronic device is a gyroscope; the fourth electronic device and the fifth electronic device are vehicle processors.
  • the satellite signal includes: a global positioning system GPS satellite signal, a Beidou satellite navigation system satellite signal, a GLONASS satellite navigation system GLONASS satellite signal, or a Galileo satellite navigation system satellite signal .
  • this application provides an electronic device, including: one or more processors; one or more memories; one or more sensors; and one or more computer programs, wherein the one or more computers Programs are stored in the one or more memories, and the one or more computer programs include instructions, and when the instructions are executed by the electronic device, the electronic device is caused to execute any of the implementation manners of the first aspect The method described.
  • this application provides a positioning system, including: a first electronic device for collecting and outputting a second vehicle speed; a second electronic device for receiving and outputting satellite positioning data; and a third electronic device for using To collect and output the angular velocity of the vehicle; the fourth electronic device is used to execute the method described in any implementation manner of the first aspect.
  • the present application provides a vehicle, including: a vehicle body, and the electronic device as described in the second aspect, or the positioning system as described in the third aspect.
  • the present application provides a computer-readable storage medium that stores instructions in the computer-readable storage medium.
  • the instructions run on an electronic device, the electronic device executes any of the instructions in the first aspect. The method described in one implementation mode.
  • this application provides a computer program product, which when the computer program product runs on an electronic device, causes the electronic device to execute the method as described in any implementation manner of the first aspect.
  • the positioning method and system, electronic equipment, vehicle, and storage medium provided by the present application can reduce the accumulated mileage error of DR calculation, improve the accuracy of the DR calculation result, and have a better positioning and navigation experience.
  • Figure 1A is a schematic diagram of an error between the estimated position of the DR and the actual position of the vehicle in this application;
  • FIG. 1B is a schematic diagram of another error situation between the estimated position of the DR and the actual position of the vehicle in this application;
  • Figure 2 is a schematic diagram of a positioning method provided by this application.
  • FIG. 3 is a schematic flowchart of a positioning method provided by this application.
  • FIG. 4 is a schematic diagram of a DR estimated position and GPS positioning position provided by this application.
  • FIG. 5A is a schematic diagram of a scene and error situation of a positioning method provided by this application.
  • FIG. 5B is a schematic diagram of the scene and error situation of another positioning method provided by this application.
  • FIG. 6A is a schematic diagram of a scenario and error situation of another positioning method provided by this application.
  • FIG. 6B is a schematic diagram of the scene and error situation of another positioning method provided by this application.
  • FIG. 6C is a schematic diagram of a scenario and error situation of another positioning method provided by this application.
  • FIG. 7A is a schematic diagram of the error situation of another positioning method provided by this application.
  • FIG. 7B is a schematic diagram of the error situation of another positioning method provided by this application.
  • FIG. 7C is a schematic diagram of the error situation of another positioning method provided by this application.
  • FIG. 8A is a schematic diagram of the error situation of another positioning method provided by this application.
  • FIG. 8B is a schematic diagram of the error situation of another positioning method provided by this application.
  • FIG. 8C is a schematic diagram of the error situation of another positioning method provided by this application.
  • FIG. 9A is a schematic diagram of a starting scene of another positioning method provided by this application.
  • FIG. 9B is a schematic diagram of a starting scene of another positioning method provided by this application.
  • FIG. 9C is a schematic diagram of a starting scene of another positioning method provided by this application.
  • FIG. 9D is a schematic diagram of a starting scene of another positioning method provided by this application.
  • FIG. 10 is a schematic diagram of a scene of another positioning method provided by this application.
  • FIG. 11 is a schematic diagram of a scene of another positioning method provided by this application.
  • FIG. 12 is a schematic diagram of a U-turn scenario of another positioning method provided by this application.
  • FIG. 13A is a schematic diagram of a lane change scene of another positioning method provided by this application.
  • FIG. 13B is a schematic diagram of a lane change scene of another positioning method provided by this application.
  • FIG. 14 is a schematic diagram of a system architecture of a vehicle provided by this application.
  • FIG. 15 is a schematic diagram of the architecture of another positioning system provided by this application.
  • FIG. 16 is a schematic diagram of the architecture of another positioning system provided by this application.
  • FIG. 17 is a schematic diagram of data interaction of another positioning system provided by this application.
  • FIG. 18 is a schematic diagram of the architecture of another positioning system provided by this application.
  • FIG. 19 is a schematic structural diagram of another positioning system provided by this application.
  • DR calculation is based on the previous position to calculate the current position. Specifically, the DR calculation is to obtain the displacement and heading of the vehicle from the previous position based on the vehicle speed and the vehicle angular velocity, and combine the previous position to calculate the current position of the vehicle.
  • the starting position calculated by DR is recorded as P 0 (Long 0 ,Lat 0 ), the starting heading is recorded as Heading 0 , the first position calculated by DR is recorded as P 1 (Long 1 ,Lat 1 ), and its heading is recorded as Heading 1 , the nth position calculated by DR is recorded as P n (Long n , Lat n ), and its heading is recorded as Heading n .
  • V i is a vehicle speed at the i-th projection, therefore, the n-th acquisition speed obtained by the vehicle referred to as V n, the first n-1 time acquisition speed obtained by the vehicle referred to as V n-1, and the vehicle
  • the angle rotated between V n-1 and V n is denoted as ⁇ n , where ⁇ n is the angular velocity of the vehicle ⁇ n collected for the nth time, and the vehicle traveling between V n-1 and V n Time t is related.
  • ⁇ i is the angular velocity of the vehicle during the i-th DR estimation.
  • ⁇ i is positive and negative, and its unit is degree/second.
  • t is the time interval for obtaining the angular velocity, and its unit is second; for ease of processing, suppose any two data
  • the time interval t between acquisition processes is fixed and equal.
  • n is an integer greater than zero.
  • the first DR estimation position P 1 is calculated according to P 0 and the vehicle speed and the vehicle angular velocity.
  • P 1 (Long 1 ,Lat 1 ) and the heading 1 of the position can be expressed as:
  • Heading 1 Heading 0 + ⁇ 1 t
  • the DR calculation continues, and the second DR calculation position P 2 is calculated according to the first DR calculation position P 1 . Specifically, P 2 is calculated based on P 1 , vehicle speed, and vehicle angular velocity. At this time, P 2 (Long 2 , Lat 2 ) and the heading 2 of the position can be expressed as:
  • Heading 2 Heading 1 + ⁇ 2 t
  • Heading n Heading n-1 + ⁇ n t
  • the vehicle speed V i and the angular velocity ⁇ i is the main factor of the estimated position DR.
  • the DR is mainly influenced by the results of estimation of the vehicle's velocity V i.
  • the vehicle speed involved here refers to the vehicle speed used in the DR calculation process.
  • the vehicle speed obtained or collected during the DR calculation process is recorded as the second vehicle speed.
  • the obtained second vehicle speed will have an instantaneous error, and the instantaneous error of the speed will be accumulated in the DR estimation process in the way of the error of the DR estimated position, resulting in an increasing error of the DR estimated position.
  • the error of the vehicle speed will cause an error between the i-th DR estimation position and the actual position of the vehicle, and any DR estimation process after the i-th time is the i-th time
  • the DR estimation position is continued on the basis of the DR estimation position, that is, the subsequent DR estimation process will accumulate the error of the i-th DR estimation position.
  • FIG. 1A and FIG. 1B show the error between the estimated position of the DR and the actual position of the vehicle by taking an example of the straight behavior of the vehicle.
  • FIG. 1A due to the error of the DR speed, the estimated DR position is located behind the actual position of the vehicle, the estimated DR position is near intersection 2, and the actual position of the vehicle is near intersection 1.
  • Figure 1B shows the specific scenario of Figure 1A. As shown in Fig. 1B, the vehicle is traveling on the road. At this time, the vehicle is traveling to the vicinity of intersection 1. The navigation display on the vehicle displays the estimated position of DR. At this time, DR estimates that the vehicle is located near junction 2. That is, the DR speed error causes the positioning deviation of the DR estimated position.
  • junction 1 if the vehicle turns right at the current driving position (junction 1), the vehicle actually enters junction 1, but the DR estimated position of the vehicle is located at junction 2, and DR When calculating the location for route navigation, the vehicle is navigated according to the vehicle entering the intersection 2, which will further cause problems such as loss of positioning or map matching to other wrong roads.
  • DR speed is a key factor in the accuracy of DR's estimated position.
  • the use of satellite positioning has high accuracy. Therefore, in the vehicle driving scene, the satellite positioning system is mainly used to locate the vehicle position, and the DR calculation positioning method is generally used as an auxiliary positioning method of the satellite positioning method.
  • the satellite positioning system relies on the transmission of satellite signals (or satellite positioning signals) when positioning, and satellite signals are susceptible to interference. For example, in areas such as tunnels, jungles, and high-rise buildings, satellite signals are easily affected by factors such as occlusion and multipath interference. Therefore, in the area where the satellite signal is interfered, the satellite positioning method cannot be used for positioning. At this time, the DR calculation can be used to locate the vehicle position.
  • Figure 2 illustrates this situation.
  • the vehicle is driving on a straight road, and there is a tunnel on the road, and the satellite signal at the tunnel is disturbed. Therefore, as shown in Figure 2, the satellite positioning method can be used to locate the vehicle position before the vehicle enters the tunnel and after the vehicle exits the tunnel; while inside the tunnel, due to the interference of the satellite signal, the DR method is used to estimate the vehicle position , To locate the location of the vehicle.
  • a road section with good satellite signals such as the part of the road section before the vehicle enters the tunnel and after the vehicle exits the tunnel as shown in Figure 2, it can be displayed on the navigation display of the vehicle.
  • the first vehicle position located by the satellite positioning system (satellite positioning position); while on a road section with poor satellite signals, such as the tunnel section shown in Figure 2, the navigation screen displays the vehicle position calculated by DR (DR calculated position, Or dead reckoning position).
  • DR DR calculated position, Or dead reckoning position
  • satellite positioning is generally used to estimate the position of vehicles, while on road sections where satellite signals are interfered, such as viaducts, jungles, high-rise areas, underground passages, and tunnels as shown in Figure 2. At least one type is used to locate the vehicle position through DR calculation.
  • the error between the satellite positioning position and the actual position of the vehicle is small, and the satellite positioning position can even be regarded as the actual position of the vehicle.
  • the satellite positioning system involved in this application may include, but is not limited to: Global Positioning System (GPS), Beidou Navigation Satellite System (Beidou Navigation Satellite System, or BDS for short), GLONASS Satellite Navigation System ( Global Navigation Satellite System (GLONASS), Galileo satellite navigation system, etc.
  • GPS Global Positioning System
  • Beidou Navigation Satellite System Beidou Navigation Satellite System
  • BDS Beidou Navigation Satellite System
  • GLONASS Satellite Navigation System Global Navigation Satellite System
  • Galileo satellite navigation system etc.
  • GPS Global Positioning System
  • GPS Beidou Navigation Satellite System
  • GLONASS Global Navigation Satellite System
  • Galileo satellite navigation system etc.
  • the positioning manner shown in FIG. 2 is only an exemplary implementation manner. In an actual implementation scenario, the DR positioning manner may also be fully utilized to locate the vehicle position. In another possible embodiment of the present application, no matter whether the satellite signal is good or not, the DR calculation can be used to locate the vehicle position. That is, this application does not specifically limit which positioning method is used on a road section with a better satellite signal.
  • the satellite positioning position when the satellite signal is good can be used (the vehicle position determined by the satellite positioning method, for example, the GPS positioning position, combined with the DR estimated position, to correct the DR speed to To a certain extent, reduce the problem of DR positioning error caused by DR speed error.
  • the embodiment of the present application provides a positioning method, which can be referred to FIG. 3.
  • the positioning method can be implemented as follows:
  • S302 When the vehicle is running in the first environment, display the position of the first vehicle located by the satellite positioning system, and the quality of the satellite signal in the first environment meets the preset quality requirement.
  • the vehicle's navigation display screen can display the location obtained by different means. If the vehicle enters the second environment from the first environment, the position displayed on the navigation display screen is changed from the first vehicle position to the second vehicle position; on the contrary, if the vehicle enters the first environment from the second environment, the navigation The position displayed on the display screen is changed from the second vehicle position to the first vehicle position.
  • the first environment and the second environment are related to the quality of the satellite signal.
  • the tunnel in FIG. 2 because the satellite signal is blocked, which does not meet the preset quality requirements, the tunnel belongs to the second environment;
  • the quality of the satellite signal is good, which can meet the preset quality requirements, and the outside of the tunnel belongs to the first environment.
  • the first vehicle position is the position of the vehicle obtained by the satellite positioning system for real-time positioning
  • the satellite positioning position refers to the historical position before the current time. Satellite positioning position is different.
  • the second vehicle position is the vehicle position calculated by the DR in real time, and the dead reckoning position here refers to the historical DR estimated position before the current time. The two are different.
  • the error between the previous GPS positioning position and the previous DR estimated position can be used to correct the second vehicle speed, and the revised speed can be used for dead reckoning.
  • the first vehicle speed is obtained by correcting the speed of the second vehicle using a speed compensation factor, and the speed compensation factor is based on the satellite positioning position and the dead position Obtained by inferred location.
  • the DR calculation is started. After the vehicle has moved forward for a certain distance, the position of the vehicle calculated by the nth DR is recorded as P n . At this time, the GPS signal is good, and the GPS positioning position P Gn can be obtained. As mentioned above, when the GPS signal is good, the GPS positioning position can be regarded as the actual position of the vehicle. Therefore, the distance difference between P Gn and P n can be obtained and denoted as P Gn P n . It can be understood that P Gn P n is actually caused by the speed error in a period of travel from P 0 to P n .
  • the position error of the vehicle during this period of travel can be averaged to the speed to obtain the DR speed and the vehicle The speed error of the actual speed during this period of travel.
  • the second vehicle speed V vehicle is the vehicle speed obtained in real time. Therefore, in the DR calculation process, after the real-time second vehicle speed is obtained, the speed compensation factor can be directly used for real-time correction to obtain Real-time first vehicle speed, and use the first vehicle speed to perform real-time DR calculation. Among them, the speed compensation factor can be obtained currently, or it can be obtained and recorded before.
  • the speed compensation factor ⁇ can be positive or negative.
  • the GPS positioning position P Gn is in front of the DR estimated position P n , that is, the dead reckoning position falls behind the satellite positioning position, it means that the vehicle speed used in the DR calculation process is slower than the actual vehicle speed, so ,
  • the obtained speed compensation factor ⁇ is a positive value.
  • the corrected vehicle speed V is greater than the collected vehicle speed V vehicle .
  • Figure 4 shows a relationship between P Gn and P n.
  • P n (Long n , Lat n ) is the longitude and latitude of the vehicle position calculated by DR after the vehicle has traveled for a certain distance.
  • P Gn (Long G , Lat G ) is the GPS positioning corresponding to P n Heading n is the heading of the n-th DR estimated position,
  • ⁇ represents the direction angle formed by P n and P Gn
  • ⁇ represents the angle between ⁇ and Heading n.
  • the direction angle ⁇ can be obtained according to the coordinates of P Gn and P n:
  • the speed compensation factor ⁇ can be expressed as:
  • the estimated DR position P n is in front of the GPS positioning position P Gn , that is, the dead reckoning position falls in front of the satellite positioning position, it means that the vehicle speed used in the DR calculation process is faster than the actual vehicle speed. Therefore, the acquired speed compensation factor ⁇ is a negative value.
  • the corrected vehicle speed V is less than the collected vehicle speed V vehicle .
  • the speed compensation factor is obtained based on the satellite positioning position and the dead reckoning position when the preset correction condition is satisfied.
  • the preset correction condition may at least include but is not limited to: the satellite signal quality meets the preset quality requirement.
  • the satellite signal directly coming from the satellite in addition to the satellite signal directly coming from the satellite, it can also be relayed through a ground base station, or it can also be coordinated with a ground base station signal.
  • satellite signal as the GPS signal as an example.
  • the quality of the GPS signal can be determined from at least one of the number of satellites, positioning accuracy, and signal strength.
  • the preset quality requirements may include but are not limited to the following conditions:
  • the satellite is in a valid positioning state
  • the satellite's horizontal accuracy factor is less than or equal to the preset accuracy threshold
  • the number of satellites in a valid positioning state is greater than or equal to a preset first number threshold
  • the total number of satellites whose signal strength is greater than or equal to the preset strength threshold is greater than or equal to the preset second number threshold.
  • the thresholds involved in the foregoing conditions can be preset according to actual scenarios.
  • the accuracy threshold may be preset to 1.5
  • the first number threshold may be preset to 5
  • the second number threshold may be preset to 4
  • the intensity threshold may be preset to 35db.
  • the GPS signal in addition to satisfying the aforementioned 4 conditions to determine the better implementation of the GPS signal, it can also be preset to satisfy at least one (or at least two, or at least three) of the conditions, It is determined that the GPS signal is better. That is, in the actual scene, the preset quality requirements can be customized according to the actual scene.
  • the GPS receiving module can receive GPS messages sent by GPS satellites, and compare the data carried in the GPS messages with the preset quality requirements to determine that the vehicle is currently in the first environment with better GPS signal quality , Is still in the second environment with poor GPS signal quality.
  • the data carried in the GPS message may include but is not limited to the following: recommended positioning information (Recommended Minimum Specific GPS/TRANSITData, RMC) message, visible satellite information (GPS Satellites in View, GSV) ) Messages and GPS positioning information (Global Positioning System Fix Data, GGA) messages.
  • recommended positioning information Recommended Minimum Specific GPS/TRANSITData, RMC
  • visible satellite information GPS Satellites in View, GSV
  • GPS positioning information Global Positioning System Fix Data, GGA
  • the RMC message can include but not limited to positioning status (valid positioning or invalid positioning), latitude format, latitude hemisphere (northern hemisphere or southern hemisphere), longitude format, longitude hemisphere (east or west longitude), ground heading and other information, GSV
  • the message may include, but is not limited to: the total number of visible satellites, signal-to-noise ratio, and other information
  • the GGA message may include, but is not limited to, the Horizontal Dilution of Precision (HDOP) and other information.
  • HDOP Horizontal Dilution of Precision
  • the preset quality requirements may be further restricted in terms of duration.
  • the satellite signal quality satisfies the preset quality requirements, which may include but is not limited to the following design methods:
  • the satellite signal meets the preset quality requirement instantaneously, as long as the satellite signal quality meets the preset quality requirement, it is determined that the vehicle is in the first environment.
  • the continuous duration range can be preset according to actual needs. For example, it can be preset that the GPS signal meets the aforementioned conditions within 5s (or 3s, etc.), then the GPS signal is better for a short time, and the vehicle is in the first environment.
  • This processing method is more conducive to ensuring the accuracy of the acquired satellite positioning position, which is also conducive to improving the accuracy of the speed compensation factor obtained therefrom, and in turn, is conducive to reducing the error of the second vehicle position.
  • the correction conditions may also include at least one of the following:
  • the mileage of the vehicle reaches a preset distance threshold
  • the mileage difference between the dead reckoning position and the satellite positioning position is greater than a preset error threshold
  • the vehicle satisfies a preset straight-going condition.
  • the DR speed is corrected when the GPS signal is good in a scenario where the vehicle is traveling straight ahead. Therefore, the vehicle needs to meet the straight traveling condition.
  • the straight travel conditions may include, but are not limited to:
  • the change in the heading angle of the vehicle is less than or equal to a preset angle
  • the vehicle travels in one direction on a straight road from the starting point.
  • Figure 4 further shows two auxiliary lines: auxiliary line 1 and auxiliary line 2, and the angle ⁇ between auxiliary line 1 and auxiliary line 2 and Heading n (can be regarded as the amount of change in heading angle) is
  • the preset angle such as 10 degrees or 5 degrees, is used to indicate whether the vehicle is going straight.
  • the heading angle of the vehicle can be obtained by processing the angular velocity of the vehicle.
  • the included angle ⁇ is less than or equal to the preset angle, for example, the included angle ⁇ in Figure 4 is within the range of 10 degrees (or 5 degrees, custom preset), the DR heading of the vehicle and the actual driving heading of the vehicle have little error, and the vehicle is still In the straight state, at this time, correcting the vehicle speed can reduce the mileage error accumulated in the aforementioned DR calculation process to a certain extent.
  • a map can be further used to determine whether the vehicle is in a straight state, that is, to determine whether the vehicle is driving in a one-way direction on a straight road starting from the starting point.
  • a map of the area where the vehicle is located can be obtained, so that the road where the vehicle is currently located and the location of the vehicle on the road can be located through P n. Therefore, according to the shape of the road, determine whether the road is a straight road or a curve (or other road conditions, for example). Then, if the road is a straight road, you can get the position of the vehicle on the road and the curve of the road. The length of the route between roads (or exits).
  • the length of the route is greater than the preset length threshold, such as 50 meters, it is determined that the vehicle is going straight on the road; conversely, if the route length is less than the preset length threshold, the vehicle may be To change lanes or enter a curve, it can be regarded as the vehicle is not going straight on the road.
  • the number and value of the length threshold can be preset according to needs, and will not be repeated.
  • the vehicle speed when the vehicle speed is corrected, it can also be determined whether the vehicle is in a straight state according to the aforementioned method.
  • the DR speed is corrected by the method provided in this application. .
  • the component of the vehicle speed in the direction of travel can also be used to implement the correction of the DR speed.
  • this processing method can also reduce the DR estimation error to a certain extent, the DR estimation error in the case of non-straight driving is still larger compared with the case of the vehicle traveling straight.
  • Figures 5A and 5B show a vehicle driving scene: a scene where the vehicle is driving straight from left to right in the direction of the dashed arrow on a straight section. There is an interference section on the straight section, and on the interference section, the GPS signal The quality has dropped drastically.
  • this application is when the GPS signal is good, the GPS signal quality meets the preset quality requirements, and the vehicle is traveling straight. At this time, the preset correction conditions are met, and the speed compensation factor can be obtained at this time. Therefore, in the subsequent DR estimation process, the speed compensation factor can be used to correct the second vehicle speed to obtain the DR estimation position.
  • the correction of the second vehicle speed is continuously performed during the DR estimation process. Therefore, in FIG. 5A, it is indicated as "corrected vehicle speed", which means that the vehicle speed is corrected from this position.
  • corrected vehicle speed which means that the vehicle speed is corrected from this position.
  • the vehicle speed is corrected.
  • the speed compensation factor is also used to correct the second vehicle speed and use the corrected DR calculation is performed on the first vehicle speed.
  • the speed compensation factor used in the speed correction can be calculated in real time according to the corresponding P Gn and P n at the correction point; or, it can be calculated before that; or, also It can be recorded and stored directly. Later, in the subsequent DR estimation process, the compensation factor can be used to modify the DR speed. That is, the correction of the DR speed is a continuous processing process.
  • the "correction of vehicle speed” and “correction point” involved in the subsequent drawings and descriptions of this application represent the starting point of the speed correction process. Therefore, in an embodiment of the present application, the speed compensation factor of the DR positioning can be obtained at the correction point for correcting the vehicle speed shown in FIG. 5A, and the DR speed can be corrected from the correction point.
  • the speed compensation factor is obtained after the preset correction conditions are met; and the correction for the second vehicle speed can be carried out at any position, or from any position as the starting point of the correction, in the subsequent DR The calculation process continues.
  • the speed compensation factor of the DR positioning can also be obtained only at the correction point, but the DR speed is not corrected temporarily. For example, if the vehicle is driving on a section of road where the GPS signal continues to be good, the GPS signal is always good, and the DR estimated position can be calculated in the background, but it is not used to display on the navigation screen (in the first environment, the navigation screen displays the first A vehicle position), the speed compensation factor of the DR positioning can be obtained at the correction point, without the need to correct the DR speed. For another example, if the DR calculation only starts in the second environment, the speed compensation factor can be obtained at the correction point in advance. Therefore, when the vehicle enters the second environment, the speed compensation factor can be used to start real-time correction of the second environment. The vehicle speed, and the corrected first vehicle speed is used to calculate the vehicle position.
  • GPS positioning data can also be further used to correct the DR estimated position.
  • GPS positioning data to correct the DR estimated position, you can directly obtain the GPS positioning position when the GPS signal is good, and replace the DR estimated position with the GPS positioning position.
  • the vehicle position displayed on the navigation display screen is changed from the second vehicle position to the first vehicle position. If the two positions are significantly different, the vehicle position on the navigation display screen will jump from one position to another; but if the two positions are less different, the vehicle position displayed on the navigation display does not change much, and the user It may be imperceptible.
  • the corrected DR estimation position can also be used as the starting point of the DR estimation. That is, after correcting the DR estimation position, the current correction point is used as the starting point of the DR estimation, and the next round of DR estimation is started.
  • FIG. 5A shows a schematic diagram of a scene in which the DR estimated position is simultaneously corrected at the speed correction point.
  • the actual position of the vehicle is marked as 11, while 13 represents the DR estimated position obtained by DR calculation using the first vehicle speed, and 12 represents the DR estimated position obtained by DR calculation using the second vehicle speed .
  • the curve 121 represents the second error curve between the DR estimated position 12 of the uncorrected speed and the actual position 11 of the vehicle.
  • the angle of the second error curve 121 is recorded as the second error angle, which is represented by a; 131 represents the first error curve between the DR estimated position 13 of the corrected DR speed and the actual position 11 of the vehicle.
  • the angle of the first error curve 131 is marked as the first error angle, which is represented by b, and the label of b is There is no practical significance for distinguishing, as shown in b1 and b2 in Fig. 5A and Fig. 5B. The following icons will remain unchanged and no additional explanation will be given.
  • the vehicle As the vehicle continues to drive straight, the vehicle enters the interference section and continues to travel in the interference section, and the DR estimated position begins to accumulate errors.
  • the values of the second error curve 121 and the first error curve 131 both increase with the increase of the mileage, that is, both the second error and the first error increase with the increase of the mileage.
  • the deviation between the uncorrected DR estimated position 12 and the actual vehicle position 11 is greater than the deviation between the corrected DR estimated position 13 and the actual vehicle position 11 .
  • the increase range of the second error curve 121 is greater than the increase range of the first error curve 131, and the second error angle a is greater than the first error angle b (including b1 and b2). It can be understood that by correcting the vehicle speed when the GPS signal is good, the position error in the subsequent DR estimation process can be effectively reduced.
  • the corrected vehicle speed can be closer and closer to the true speed of the vehicle, thereby reducing the error of the vehicle speed used by the DR, thereby also improving the DR estimation result The accuracy rate.
  • the growth trend of the second error between the DR estimated position 12 of the uncorrected speed and the actual vehicle position 11 is the same.
  • the included angle of the second error included angle a constant. This is because if the estimated position of DR is corrected only at the correction point, and the vehicle speed is not corrected, then, without considering the variables, for example, the speed error may be different, the road condition may be different, and the tire wear may be different.
  • the error of DR estimated position due to vehicle speed is basically unchanged.
  • the DR speed is continuously corrected during the DR calculation process, after multiple corrections, the DR speed is getting closer and closer to the actual speed of the vehicle, which is beneficial to further reduce the position error of the DR calculation.
  • the error curve (first error curve 131) of the DR estimated position increases less and less.
  • the first error angle b keeps increasing. If it becomes smaller, the first error angle b1 of the last DR estimation process is greater than the first error angle b2 of this DR estimation process.
  • This application is not only applied to correct the DR speed on the interference road section with poor GPS signal.
  • the DR calculation method can still be used to locate the vehicle position. For example, the vehicle is in the first position in Figure 5A. During driving in the environment, the DR calculation can still be continued. At this time, the speed correction method provided by this application can still be used to correct the vehicle speed (DR speed) used in the DR estimation.
  • the correction and update of the DR estimated position has nothing to do with the DR speed correction point.
  • the correction point for the DR estimated position can be customized.
  • the GPS signal can be better after the vehicle has traveled a certain distance, such as 1km.
  • the DR estimated position is corrected again.
  • specific instructions will be given later.
  • the driving scene shown in FIG. 5B is the same as the scene shown in FIG. 5A and will not be described in detail.
  • the starting point of the DR calculation is not shown in the implementation shown in FIG. 5B, and the DR calculation has already started during a period of the journey before the vehicle enters the interference road section.
  • the values of the second error curve 121 and the first error curve 131 both increase with the increase in mileage, and the angle a between the two and Same as b0. That is, at this time, the deviation between the estimated DR position 12 of the uncorrected speed and the actual position 11 of the vehicle is equal to the deviation between the estimated DR position 13 and the actual position 11 of the vehicle after the speed is corrected.
  • the vehicle continues to travel and reaches the first speed correction point before entering the interference section (the vehicle is going straight and the GPS signal is good). Since the vehicle speed used by DR is corrected, the value of the first error curve 131 increases with the increase in mileage As shown in Figure 5B, the first error angle is reduced from b0 to b1, and the deviation between the DR estimated position 13 and the actual position 11 of the vehicle after the speed correction has increased, but the increase is greatly reduced . While the second error curve 121 does not correct the vehicle speed, the increase rate remains unchanged, and the second error angle is still a. The deviation between the DR estimated position 12 of the uncorrected speed and the actual vehicle position 11 continues to increase according to the increase rate corresponding to a. Big. Therefore, as shown in FIG.
  • the deviation between the estimated DR position 12 of the uncorrected speed and the actual position 11 of the vehicle is greater than the deviation between the estimated DR position 13 of the speed corrected and the actual position 11 of the vehicle.
  • the position error estimated by the DR is not cleared at this time.
  • the vehicle travels to the interference road section, and after driving out of the interference road section, the vehicle speed is corrected again.
  • the first error angle decreases again, from b1 to b2; and the second error curve 121
  • the angle between the two errors remains a unchanged.
  • the deviation between the estimated DR position 12 of the uncorrected speed and the estimated DR position 13 of the corrected speed also gradually increases.
  • the first error angle is reduced from b2 to b3 again; the second error angle remains a unchanged.
  • the DR estimated position error continues to increase.
  • the increase in the position error estimated by the DR can be effectively reduced.
  • this can also reduce the deviation of the estimated position of the DR from the actual position of the vehicle to a certain extent.
  • Figures 6A to 6C show another vehicle driving scenario: the vehicle is traveling straight on the road. There are at least two interference sections on the road. The GPS signal quality of the interference section is poor and belongs to the second environment. Therefore, the DR Calculate to locate the vehicle position. As shown in FIGS. 6A to 6C, there are some road sections with better GPS signals between any two adjacent interference road sections. It can be understood that, in an actual scenario, among at least two interference road sections, any two interference road sections cause the GPS signal to be interfered with by the same or different reasons. For example, when a vehicle is driving, it often encounters a situation where the distance between two tunnels is relatively close, and there is a short open-air area between the two tunnels, forming multiple interference road sections.
  • the GPS signal when a vehicle is driving in a straight line in a forested area, the GPS signal will be temporarily blocked by forest trees or tall buildings from time to time. Or, for another example, when a vehicle is traveling in a straight line in a city, the GPS signal is temporarily blocked by an overpass and the GPS signal is poor, and the vehicle is traveling in the second environment; after driving out of the overpass, the GPS signal is restored to good condition and returns to the first environment Driving; afterwards, driving to an area with many tall buildings, due to the influence of multipath effects, the GPS signal is affected again, and the first environment enters the second environment again.
  • FIGs. 6A to 6C show the situation where the speed compensation factor is used to correct the vehicle speed immediately after the speed compensation factor is obtained. It is understandable that the present application is not limited to this processing method, and will not be repeated.
  • the values of the second error curve 121 and the first error curve 131 both increase with the increase in mileage, and the error increases; due to the speed correction, the increase of the first error curve 131 is smaller than the second error The rise of curve 121.
  • the deviation between the uncorrected DR estimated position 12 and the actual vehicle position 11 is greater than the deviation between the corrected DR estimated position 13 and the actual vehicle position 11.
  • the speed correction point is used as the starting point for the next round of DR calculation, and the position error calculated by the DR is the smallest.
  • suspension correction processing can also be executed in multiple interference sections.
  • the suspension of the correction processing may include, but is not limited to: suspension of the correction of the vehicle speed, and/or suspension of the update of the starting point of the DR estimation (that is, the suspension of the correction of the DR estimation position).
  • FIG. 6B shows a situation where the vehicle speed is suspended to be corrected.
  • the vehicle when there are multiple interference road sections, the vehicle can enter the interference road section, and the DR speed correction can be suspended until the vehicle completely drives out of the last interference road section, and then the vehicle speed can be corrected. Then, compared to the scene shown in Fig. 6A, the vehicle suspends speed correction on a non-interference road section between two interference road sections. At this time, there are two speed correction points in Fig. 6B.
  • the vehicle speed and the DR estimation position are corrected.
  • the values of the second error curve 121 and the first error curve 131 both increase with the increase of the mileage.
  • the increase rate of the DR estimation process remains unchanged.
  • the second error included angle a is greater than the first error included angle b.
  • the GPS signal recovered well, and the preset correction conditions were met, and the vehicle speed was corrected again. It can be understood that in the DR calculation process after the second speed correction point, the first error angle b decreases, while the second error angle a does not change.
  • the correction for the DR speed and the correction for the estimated position of the DR may not be synchronized. Then, when the DR speed correction is suspended on multiple interference road sections, the correction of the DR estimated position may not be suspended.
  • there is another possible implementation method that is, on the non-interference road section between the two interference road sections, correct the DR estimated position.
  • the position error calculated by the DR is cleared, but it is executed after the position correction point.
  • both the second error angle a and the first error angle b remain unchanged.
  • the preset correction conditions are met, and after the DR speed is corrected, the first error angle b decreases.
  • FIG. 6C shows a situation where the DR estimation position is suspended to be corrected.
  • the starting point of the DR calculation can be suspended when the vehicle enters the interference road section, until the vehicle drives out of the last interference road section, and then the starting point of the DR calculation process Make corrections. That is, after the vehicle drives out of the last interference road segment, GPS data is used to correct the vehicle position.
  • the correction for the DR speed and the correction for the DR estimated position may not be synchronized.
  • the DR estimated position is corrected at the speed correction point at the same time, while among the multiple interference road sections, the DR estimated position correction is suspended.
  • the vehicle speed is corrected when the preset correction conditions are met.
  • the first error angle is reduced from b1 to b2.
  • the deviation between the DR estimated position 13 after the speed correction and the actual position of the vehicle is getting larger and larger.
  • the speed correction point the increase in deviation has eased.
  • the GPS signal recovered well, and then use GPS data to correct the DR to calculate the position, and re-correct the vehicle speed.
  • the starting point of the suspension processing mainly involves whether there are multiple interfering road sections within the preset distance in front of the vehicle. Specifically, GPS positioning and high-precision maps can be combined to determine the road conditions ahead of the vehicle. The vehicle obtains the GPS location while driving, and then matches the GPS location with the high-precision map to match the vehicle's location on the high-precision map. After that, the road conditions in front of the road can be determined based on the high-precision map.
  • multiple interfering road sections may be caused by roadside objects such as tall buildings or forests, overpasses, underground passages and other road construction objects.
  • multiple interfering road sections can be performed in a high-precision map in advance. logo. In this way, the GPS location of the vehicle is matched to the high-precision map. If there are multiple interference road segments in the preset distance ahead of the vehicle, multiple interference road segments appear in front of the vehicle, and the suspension correction process is started.
  • the preset distance can be preset as needed.
  • the suspension correction process can be executed when multiple interference road sections are detected in front of the vehicle; or when the preset distance is long, when multiple interference road sections are detected in front of the vehicle, the The distance difference between the vehicle and the starting point of the multi-interference road section can be continuously monitored based on the GPS signal. If the distance difference is less than the preset distance difference, that is, when the vehicle is about to enter the multi-interference road section, the suspension correction process is started.
  • the vehicle When the vehicle subsequently enters multiple interference road sections, there are open road sections with good GPS signals. At this time, it can be combined with high-precision maps to determine that the vehicle has not driven out of the multiple interference road sections, and the correction processing remains suspended. Until the vehicle can receive the GPS signal and the GPS location indicates that the vehicle has driven out of the multi-interference road section, the suspension correction process is terminated, the vehicle speed is corrected, and the DR estimated position and DR heading are corrected.
  • the GPS signal is better (or better in a short time), and the vehicle speed is corrected when there is a large accumulated mileage error after the vehicle has traveled for a period of time.
  • this application uses the mileage error accumulated by the vehicle during a period of mileage to correct the vehicle speed. Then, when the vehicle mileage is short, the position error calculated by DR is small, and the impact on positioning and navigation is small, and there is no need In this case, the speed is corrected. Based on this, the distance threshold and/or error threshold can be preset to limit the accumulated mileage error accumulated by the vehicle, avoid unnecessary speed correction, and save system resources.
  • the foregoing preset correction condition may further include: starting from the starting point of the dead reckoning, the mileage of the vehicle reaches a preset distance threshold.
  • the mileage between the current position and the starting point of the DR estimation can be obtained. If the mileage is greater than or equal to the preset distance threshold, and the GPS signal is good (or GPS signal is better for a short time), you can get it Speed compensation factor to correct the vehicle speed.
  • the judgment on the mileage and distance threshold can be executed in the background in real time, regardless of the quality of the GPS signal.
  • the vehicle is just driving in the tunnel, and the GPS signal quality is poor.
  • the distance threshold can be customized according to the actual scene.
  • the value can be set by the maintenance personnel before leaving the factory, or it can be customized and modified by the user, which is not particularly limited.
  • the distance threshold can be a fixed value, for example, it is preset to 1000 meters, and no matter what road section the vehicle is driving on, the distance threshold is processed according to the distance threshold.
  • Figures 7A to 7C show this situation.
  • Figures 7A to 7C show the situation where the speed compensation factor is used to correct the vehicle speed immediately after the speed compensation factor is obtained. It can be understood that the present application is not limited to this processing method, and will not be repeated.
  • the preset distance threshold is denoted as S 2
  • the starting point of the DR calculation is preset as the speed correction point.
  • the vehicle starts to drive, taking P 01 as the starting point of the first DR calculation, and then starts the DR calculation. After that, the error generated in the DR calculation process increases with the increase of the mileage.
  • the vehicle continues to drive until the distance between P 01 and P 01 reaches S 2.
  • DR calculates the n1 position P n1 , corrects the vehicle speed at this point, and corrects the starting position and starting heading calculated by DR at the same time.
  • Get P 02 Start the second round of DR calculation process from P 02 until the driving distance from P 02 reaches S 2 . Continue to the next round of speed correction and starting point correction. While the vehicle is running, repeat the foregoing process.
  • the preset distance threshold is still expressed as S 2 , and the starting point of the DR calculation is implemented cyclically according to the preset distance threshold (assumed to be S 3 ). That is, the distance between the starting points of any two adjacent DR estimations is S 3 .
  • the first DR calculation starts at P 01.
  • the vehicle continues to travel and the travel distance from P 01 reaches S 2.
  • DR calculates the n1 position P n1 , Start to correct the vehicle speed at P n1 .
  • the increase in the cumulative error calculated by the DR starts to slow down, and the error angle decreases from a to b1.
  • the cumulative position error calculated by the first DR is not cleared, and continues to accumulate on the basis of the original position error until the driving distance between the vehicle and P 01 reaches S 3 , Update the starting point of DR estimation at P 02 , at this time, the position error of DR estimation is cleared.
  • the position error will be accumulated as the mileage increases according to the way the error angle is b1. After that, while the vehicle is running, the aforementioned process is repeated. Through the aforementioned speed correction processing, the cumulative error generated in the DR calculation process is reduced, and the error angle is gradually reduced, as shown in FIG. 7A, a>b1>b2.
  • the first DR calculation is started at P 01 , and the vehicle continues to travel and the travel distance from P 01 reaches S 2 , then the vehicle speed starts to be corrected at the n1 position P n1
  • the increase in the cumulative error calculated by DR begins to slow down, and the error angle is reduced from a to b1.
  • the position error estimated by DR continues to accumulate, the vehicle continues to travel, and the travel distance from P 01 reaches S 2.
  • the starting point of the DR estimation is updated at P 02, and the vehicle speed is corrected again. Therefore, as shown in FIG. 7C, the error angle estimated by DR is reduced from b1 to b2.
  • different distance thresholds can also be preset based on different road conditions on various road sections. For example, on a non-interference road section where the GPS signal continues to be good, the DR estimated position and DR heading can be corrected directly through GPS data. Therefore, there is no need to frequently correct the vehicle speed. In this case, a longer distance threshold can be preset to Reduce the frequency of speed correction. For another example, for sections with many tall buildings and overpasses, the vehicle speed can be corrected as quickly as possible to avoid accumulated mileage errors. In this case, a shorter distance threshold can be preset to increase the speed correction frequency.
  • the aforementioned preset correction condition may further include: the mileage difference between the dead reckoning position and the satellite positioning position is greater than a preset error threshold.
  • the mileage difference between the GPS positioning position and the DR estimated position can be obtained on a road section with a better GPS signal. If the mileage difference is greater than or equal to the preset second error threshold, the speed compensation factor can be obtained. To correct the vehicle speed.
  • This design requires that the GPS signal can be obtained, which is realized after the GPS positioning position is obtained. Compared with the previous design, it can save system resources to a certain extent.
  • Figures 8A to 8C show this situation.
  • Figures 8A to 8C show the situation where the speed compensation factor is used to correct the vehicle speed immediately after the speed compensation factor is obtained. It can be understood that the present application is not limited to this processing method, and will not be repeated.
  • the preset second error threshold is denoted as S 1
  • the starting point of the DR calculation is preset as the speed correction point.
  • the vehicle starts to drive, taking P 01 as the starting point for the first DR calculation, and then starts the DR calculation.
  • the error generated by the DR calculation process increases with the increase of the mileage.
  • the vehicle continues to travel, and the position error continues to accumulate until it reaches S 1.
  • DR calculates the n1 position P n1 , corrects the vehicle speed at this point, and corrects the starting position and starting heading calculated by DR to obtain P 02 .
  • Start the second round of DR calculation process from P 02 until the accumulated mileage error reaches S 1 again.
  • the increase in the cumulative error generated in the DR calculation process is reduced, and the error angle (the angle between the error curve and the mileage line) is gradually reduced, as shown in FIG. 8A, a>b1>b2.
  • the preset second error threshold is still expressed as S 1 , and the starting point of the DR calculation is implemented cyclically according to the preset second error threshold (assumed to be S 3 ). That is, the distance between the starting points of any two adjacent DR estimations is S 3 .
  • the first DR calculation starts at P 01 , and the position error continues to accumulate until it reaches S 1.
  • DR calculates the n1th position P n1 , and starts to correct the vehicle at P n1 Speed, as shown in Figure 8B, after correcting the vehicle speed, the increase in the cumulative error calculated by DR starts to slow down, and the error angle decreases from a to b1. Since the starting point of DR is not corrected at P n1 , the cumulative position error calculated by the first DR is not cleared, and continues to accumulate on the basis of the original position error until it reaches P 02 . Update the starting point of DR estimation at P 02 , at this time, the position error of DR estimation is cleared.
  • the position error will be accumulated as the mileage increases according to the way the error angle is b1. After that, while the vehicle is running, the aforementioned process is repeated. Moreover, in the implementation as shown in FIG. 8B, the distance between the correction point and the starting point gradually increases, and it may happen that the speed correction is not performed during a DR estimation process in the future.
  • FIG. 8C shows a situation where two second error thresholds are preset.
  • the first DR calculation is started at P 01 , and the position error continues to accumulate until it reaches S 1 , then the vehicle speed starts to be corrected at the n1- th position P n1 .
  • the vehicle speed is corrected, DR
  • the increase in the estimated cumulative error begins to slow down, and the error angle decreases from a to b1.
  • the position error calculated by DR continues to accumulate until it reaches the second second error threshold S 4.
  • the starting point of the DR calculation is updated, and the vehicle speed is corrected again.
  • the error angle calculated by the DR is reduced from b1 to b2. .
  • the speed compensation factor of the current position can be obtained according to the aforementioned method on a road section with a better GPS signal, and the speed compensation factor is greater than or equal to the preset first error threshold, then the vehicle speed is corrected.
  • This design requires that the GPS signal can be obtained, which is realized after the GPS positioning position is obtained. Compared with the previous design, it can save system resources to a certain extent.
  • the second error threshold and the first error threshold can also be customized according to actual scenes, which will not be repeated here.
  • the error threshold and/or distance threshold conditions can be further satisfied.
  • the current DR estimated position P n is used as the correction point of the vehicle speed.
  • the GPS is better for a short time (assuming that the GPS signal lasts for 2s is better) and the preset distance threshold is met (assuming the driving distance is greater than or equal to 1km).
  • the preset distance threshold is met (assuming the driving distance is greater than or equal to 1km).
  • the vehicle speed correction can be achieved under the condition that the GPS is better for a short time (assuming that the GPS signal lasts for 2s is better) and the preset distance threshold (assuming the driving distance is an integral multiple of 1km). At this time, if the vehicle travels to the interference section and the mileage reaches 1km, which meets the preset distance threshold, but the GPS signal of the interference section is poor, the vehicle speed can be temporarily not corrected as shown in Figure 5A. Wait for the vehicle to drive out of the interference section and the vehicle's mileage reaches 2km. Check again whether the GPS signal meets the requirements. If it does, then revise the speed of the vehicle; if not, wait until the mileage reaches 3km, and then check the GPS signal again... until the vehicle drives. When entering the non-interference road section, when the GPS signal is good for 2s, the vehicle speed will be corrected immediately.
  • the preset correction conditions in the DR calculation process may also include but are not limited to: the DR calculation position can correspond to the GPS positioning position. That is, there is GPS positioning data at the same time corresponding to the current DR estimation data.
  • this correction condition can be implemented by setting the receiving and output frequency of satellite messages, the collection frequency of the gyroscope, and the frequency calculated by the DR. It can be seen that the main set frequency is appropriate, and this condition can be achieved.
  • the GPS module outputs positioning information through the RS232 interface in NMEA format messages, the output frequency is 1HZ or higher, the output data rate is 115200bps or more, and the GPS module outputs clock pulse signals at the same time when there is a positioning output. (Pulse Per Second, PPS).
  • PPS Pulse Per Second
  • this application is to correct the vehicle speed used in the DR calculation process.
  • the DR calculation starts from the starting point P 0 and sequentially calculates the next position. The starting conditions to be met by the starting point P 0 of the DR calculation are now explained.
  • the dead reckoning position is obtained by successive calculations starting from the starting point, and the starting point is the satellite positioning position obtained when a preset starting condition is met.
  • the starting point P 0 is obtained by using GPS data to calibrate when the GPS signal is good.
  • the starting condition of the starting point P 0 calculated by the DR satisfies at least: the quality of the satellite signal meets the preset quality requirement. That is, the condition that the GPS signal is better (or better in a short time) is satisfied.
  • the starting point cannot be determined or updated on the road section. After the vehicle leaves the road section and the GPS conditions are met, the starting point can be determined or updated.
  • the DR estimation process can be triggered by a clock pulse signal (Pulse Per Second, PPS) signal sent by GPS.
  • PPS Phase Per Second
  • the starting point of DR will bring calculation errors to a certain extent. Therefore, the starting point can be restricted from at least one of speed and mileage to avoid errors caused by starting.
  • the starting condition of the starting point P 0 calculated by the DR may also include but not limited to at least one of the following conditions:
  • the vehicle speed reaches the preset starting speed threshold
  • the mileage of the vehicle reaches the preset starting mileage threshold.
  • the vehicle speed is obtained by the number of turns of the tires.
  • the vehicle speed reaches the preset starting speed threshold, and The current GPS signal quality is good, and the GPS positioning position is obtained as the starting position of the DR estimation, and the GPS heading is obtained as the starting heading of the DR estimation, and the DR estimation is started.
  • the starting mileage threshold is preset
  • the number of turns of the tires is used to calculate the mileage of the vehicle after starting (or, if the GPS signal is better, GPS data can also be used to obtain the mileage after starting).
  • the GPS positioning position is obtained as the starting position for DR estimation , And, obtain the GPS heading as the starting heading for DR calculation, and start DR calculation.
  • the mileage may also be: the mileage from the moment when it is judged whether to perform the DR calculation to the current moment.
  • the starting speed threshold and the starting mileage threshold can be preset according to actual needs.
  • the starting speed threshold can be preset to 5m/s.
  • the starting mileage threshold may be preset to 100 meters.
  • the starting point P 0 calculated by DR may also include: the vehicle’s navigation is stable.
  • the so-called stable heading means that the change in the heading angle of the vehicle (the included angle ⁇ as shown in Figure 4) is less than the preset angle within the preset time range. For example, if the heading angle of the vehicle changes less than 3 degrees within 5 consecutive seconds, the heading of the vehicle is stable.
  • GPS data, vehicle speed data, and angular velocity data are collected from the start of the vehicle, and based on these data, it is judged whether the aforementioned starting conditions are met, and if so, the starting point is determined based on the GPS data P 0 , and start DR calculation.
  • the starting conditions and preset correction conditions will now be illustrated with examples in conjunction with the vehicle starting scenes shown in FIGS. 9A to 9D.
  • the starting point of data collection is denoted as A
  • the end point of data collection is denoted as B.
  • the vehicle starts on the undisturbed road section and continues to travel.
  • the vehicle starts to collect data when it starts, and based on the collected data, it starts to determine whether the aforementioned initial conditions are met, and if so, the DR calculation starts.
  • the correction point can be determined according to the aforementioned preset correction conditions.
  • the data collection starting point A can be updated, that is, the DR estimation position is corrected at this position, and the next round of DR estimation is started.
  • the preset correction conditions are as mentioned above.
  • the vehicle speed can be corrected at any position after DR estimation; or, in addition to the better relevant conditions of GPS, the preset conditions must also be satisfied.
  • the distance threshold and/or the error threshold when these correction conditions are met, the vehicle speed can be corrected, which will not be repeated.
  • FIGS. 9B and 9C show a situation where the vehicle starts on a non-interference road section, and there is an interference road section with a poor GPS signal before the start.
  • the starting point of the vehicle if the starting point of the vehicle is close to the entrance of the interference section, data may not be collected temporarily before entering the interference section, but data will be collected after the vehicle leaves the interference section. If the collected data meets the preset starting condition, the starting point of the DR calculation can be updated, and the vehicle speed can be corrected when the aforementioned preset correction condition is satisfied.
  • the GPS data cannot be collected in time before the vehicle enters the tunnel, and the starting point of the DR calculation cannot be determined in time.
  • the vehicle starts to collect data. If the starting point of the vehicle is far from the entrance of the interference section, there is enough time to use GPS data to obtain a more accurate starting point for DR estimation before the vehicle enters the interference section. At this time, when the vehicle exits the tunnel, the vehicle speed is corrected. At this time, the correction point can be used as the data collection end point, and the starting point of the DR estimated position can be corrected again. In addition, compared to the situation shown in FIG. 9B, in the scenario shown in FIG. 9C, since the DR estimation process is started before entering the tunnel and the estimation error starts to accumulate, the speed correction point is closer to the tunnel exit than the situation shown in FIG. 9B.
  • FIG. 9D shows a scene where the vehicle starts on the interference road section and gradually enters the non-interference road section.
  • a vehicle starts from an underground garage and drives straight out of the underground garage; another example is a situation where the GPS signal is blocked by trees, and the vehicle starts in the woods and drives out of the woods area.
  • the starting point of the DR calculation cannot be obtained, and the DR calculation cannot be performed. Therefore, after the vehicle moves out of the interference area, data will be collected, and the starting point of the DR calculation will be determined based on the aforementioned starting conditions, and the DR calculation will be started, and the vehicle speed will be corrected when the preset correction conditions are met.
  • the speed correction point can be used as the end point B of the data collection process, and the starting point A of the data collection can be updated.
  • the DR calculation process has been calculated in real time in the background, which involves the issue of updating the starting point of the DR calculation.
  • update the DR calculation starting point is to re-acquire GPS data, vehicle speed data, and angular velocity data, and based on these data, determine whether the aforementioned starting conditions are met in real time, and if so, update the starting point P 0 according to the GPS data, and Start the DR calculation of subsequent roads from the updated starting point.
  • the starting point of the heading calculation is the satellite positioning position acquired when the preset starting update condition is satisfied and the preset starting condition is satisfied.
  • DR can be used to estimate the vehicle position.
  • the starting conditions are as mentioned before, and will not be repeated.
  • the estimated number of dead reckoning calculations reaches a preset threshold of times
  • the mileage of the vehicle reaches a preset distance threshold
  • the mileage difference between the satellite positioning position and the dead reckoning position is greater than a preset error threshold
  • the amount of change in the heading angle of the vehicle is greater than a preset angle
  • the estimated times of the current DR estimation can be obtained. If the current estimated times reaches the preset times threshold, the error of the DR estimation result may be large, and the starting point of the DR estimation is updated.
  • the starting point calculated by the DR is updated. For example, the mileage difference between the current DR calculation point and the DR starting point can be obtained. If the mileage difference reaches a preset distance threshold, the error of the DR calculation result may be relatively large, and the starting point of the DR calculation may be updated.
  • the odometer of the vehicle can be obtained to obtain the accumulated mileage from the starting point of the DR estimation to the current position. Therefore, if the accumulated mileage reaches the preset distance threshold, the error of the DR estimation result may be relatively large, and update The starting point of DR calculation.
  • the correction point (the starting point for starting to correct the vehicle speed) coincides with the updated starting point.
  • the angular velocity of the vehicle can be obtained in real time to obtain the change in the heading angle of the vehicle. If the change in the heading angle is greater than the preset angle, it means that the vehicle has turned, and the starting point of the DR calculation is updated.
  • Figures 10 to 13B show several situations where the starting point of DR estimation is updated. Among them, update the starting point of DR estimation, that is, update the data collection starting point A.
  • the vehicle is driving on a T-shaped road, and the GPS signals on this road section are all good. If the vehicle continues to drive forward, the vehicle's heading deflection is relatively small, and the vehicle is still moving forward in the original driving direction, there is no need to update the starting point calculated by the DR. If the vehicle continues to drive on the T-shaped road, but due to waiting for a red light or other reasons, a short-term parking and waiting situation occurs, since the vehicle heading has not changed, there is no need to update the DR estimation starting point. Among them, the short-term parking of the vehicle is different from stalling, and the information about whether the vehicle stalls can be obtained from the vehicle controller, which will not be described in detail here.
  • the heading angle of the vehicle deflects significantly during the turning process (the heading angle changes greater than the preset angle), and the starting point of the DR estimation is updated. Specifically, GPS data, vehicle speed data, and angular velocity data are collected again, and it is determined in real time whether these data meet the aforementioned initial conditions. It can be seen that when the vehicle is turning, the vehicle heading is unstable, and it is difficult to meet the heading stability condition. Until the vehicle turns, the vehicle heading is stable. At this time, when the aforementioned starting conditions are met, the GPS positioning position and GPS heading are acquired as the starting point of the DR calculation, and the subsequent DR calculation can be started.
  • Figure 11 shows a scene where the vehicle is driving on a curve.
  • the heading angle of the vehicle deflects greatly, and the starting point of the DR calculation can be updated at this time. That is, when the variation of the heading angle of the vehicle is greater than the preset angle, GPS data, vehicle speed data, and angular velocity data are re-collected, and it is determined in real time whether the aforementioned initial conditions are met.
  • the initial conditions are not met due to the large heading deflection.
  • the heading of the vehicle is stable. At this time, when the initial conditions are met, the GPS positioning position and GPS heading are acquired as the starting point of the DR calculation, and the subsequent DR calculation can be started.
  • Figure 12 shows a scene where the vehicle turns around.
  • the starting point of the DR calculation is updated, and the starting point of the DR calculation is when the vehicle heading stabilizes after the vehicle turns around, the starting condition is met, and the starting point is updated successfully.
  • a certain buffer zone can be preset.
  • the buffer interval can be a time interval, such as within one minute.
  • the buffer zone can also be a mileage interval, such as within 50 meters.
  • the heading angle of the vehicle is deflected, take the current moment as the starting point of the time interval to obtain the heading angle of the vehicle at the end of the time interval and the amount of change between the heading angle at the beginning of the time interval, if the heading angle If the amount of change of is within the preset angle range, there is no need to update the starting point of the DR calculation; if the change of the heading angle is greater than the preset angle, the starting point of the DR calculation is updated.
  • Figures 13A and 13B show a scene where a vehicle changes lanes.
  • the vehicle starts to change lanes and the heading angle is deflected, which is recorded as the starting point between the buffer zones. Then, when the vehicle changes lanes, the heading angle continues to change, and the amount of change may be greater than the preset angle.
  • the buffer zone determine the relationship between the current heading angle and the heading angle at the starting point of the buffer zone and the preset angle.
  • the starting point of the DR calculation needs to be updated. Whether the estimation process is temporarily stopped is not particularly limited. During this process, the DR calculation can be suspended, or the DR calculation can be continued until the starting point is updated.
  • the data collection involved refers to the collection of GPS data, the second vehicle speed, and the angular velocity. Therefore, when the solution is specifically implemented, the second vehicle speed is collected by the first electronic device, the satellite positioning position (for example, GPS positioning position) is collected by the second electronic device, and the angular velocity of the vehicle is obtained by The third electronic device is collected, the first vehicle speed is corrected in the fourth electronic device, and the dead reckoning position is calculated in the fifth electronic device. In addition, among the first electronic device, the second electronic device, the third electronic device, the fourth electronic device, and the fifth electronic device, any two electronic devices are the same electronic device or are different Electronic equipment.
  • the fourth electronic device and the fifth electronic device may be the same electronic device, and the electronic device may be a vehicle processor.
  • the fourth electronic device may be a vehicle controller
  • the fifth electronic device may be a dead reckoning processor
  • the dead reckoning processor is independent of the vehicle controller.
  • the fourth electronic device may be a mobile phone processor
  • the fifth electronic device may be a vehicle controller.
  • the first electronic device and the fourth electronic device may be the same electronic device.
  • the first electronic device collects the second vehicle speed, it can directly use the speed correction factor to correct the second vehicle speed.
  • the data output by the first electronic device is the first vehicle speed that has been corrected.
  • the positioning system at least includes:
  • the first electronic device is used to collect and output the second vehicle speed
  • the second electronic device is used to receive and output satellite positioning data
  • the third electronic device is used to collect and output the angular velocity of the vehicle
  • the fourth electronic device is used to execute the method described in any one of the foregoing implementation manners.
  • the second electronic device is a satellite signal receiving device.
  • it can be a GPS module.
  • the GPS location can be obtained by analyzing the GPS message output by the GPS module.
  • the GPS module may be an on-board GPS installed in the vehicle, or may also be a GPS installed in a mobile device connected to the vehicle.
  • the GPS module can receive GPS messages sent by satellites and output GPS messages or GPS data. If the GPS positioning data of the vehicle is collected through the GPS in the mobile device, the GPS module can output the mobile device to the communication module of the mobile device, and the communication module of the mobile device will communicate the GPS message in the aforementioned short distance. Way, sent to the vehicle processor. Or, if GPS data is collected through a vehicle-mounted GPS connected to the vehicle processor, the vehicle-mounted GPS can directly output the GPS message to the vehicle processor through a connection line (for example, the operator VLAN (Provider VLAN Transport, PVT) bus) .
  • a connection line for example, the operator VLAN (Provider VLAN Transport, PVT) bus
  • CAN Controller Area Network
  • the CAN transceiver module is used to implement data interaction between the vehicle processor and each data acquisition device.
  • the vehicle-mounted GPS can output GPS messages to the CAN transceiver module, and the vehicle processor can obtain GPS messages through the CAN bus.
  • the vehicle processor receives the GPS message output by the GPS module. Before realizing the DR calculation and the vehicle speed correction process, the GPS message needs to be parsed to extract the GPS data.
  • the GPS module can also be used to parse the GPS message after it is received. At this time, the GPS module outputs GPS data, which will not be described in detail.
  • a data analysis module can be additionally provided, and the data analysis module is used to analyze the received GPS message. Perform analysis and output the parsed GPS data.
  • the vehicle-mounted GPS is connected to the vehicle controller through an RS232 interface, and the vehicle-mounted GPS outputs a GPS message in NMEA format through the RS232 interface.
  • the output frequency can be 1HZ or higher, and the output data rate is 115200bps or higher.
  • the third electronic device is an angular velocity acquisition device.
  • the angular velocity acquisition device can be a hardware device, such as a gyroscope (gyroscope, GYRO); or, the vehicle angular velocity can also be calculated through a software algorithm.
  • the angular velocity acquisition device can be a processor or a processing module. Similar to the GPS module, the angular velocity acquisition device can be mounted in a vehicle or in a portable device.
  • the angular velocity acquisition device Take the angular velocity acquisition device as a gyroscope as an example. If the gyroscope is mounted in a mobile device, the angular velocity data is transmitted through the short-range communication connection between the communication module of the mobile device and the vehicle processor. If the gyroscope and the vehicle controller can be connected through the SPI bus and exchange data. If the gyroscope is connected to the CAN transceiver module, the vehicle processor can obtain the angular velocity data of the vehicle through the CAN bus.
  • the gyroscope can collect and record the angular velocity of the vehicle in real time, and transmit it to the vehicle controller via the Serial Peripheral Interface (SPI) bus.
  • the gyroscope can transmit the angular velocity data collected regularly to the vehicle controller via the SPI bus according to a preset sampling frequency.
  • the sampling frequency of the gyroscope needs to adapt to the time interval for DR to calculate a position. For example, in a possible implementation manner, it takes 0.025 seconds for the DR to calculate a position, and the sampling frequency of the gyroscope may be 40HZ.
  • the first electronic device may be a wheel speed collection device, may be a CAN bus, or may also be a speedometer mounted in a vehicle.
  • the wheel speed acquisition device is generally mounted in the vehicle.
  • the wheel speed collection device may be an independent device mounted in the vehicle, or may be integrated in one or more processors of the vehicle.
  • the wheel speed acquisition device can communicate and interact with the vehicle controller through the CAN bus, and the vehicle controller obtains the vehicle speed through the CAN bus.
  • the acquisition frequency of the vehicle speed (or called the sampling frequency) needs to be designed according to the actual output frequency of the vehicle, which is not particularly limited in this application.
  • the DR calculation and its vehicle speed correction scheme provided by this application can be implemented in vehicles. That is, the first electronic device, the second electronic device, the third electronic device, the fourth electronic device, and the fifth electronic device are all mounted in the vehicle.
  • the first electronic device is a speed acquisition device, the vehicle bus, or a vehicle speedometer
  • the second electronic device is a satellite signal receiving device
  • the third electronic device is Gyroscope
  • the fourth electronic device and the fifth electronic device are vehicle processors.
  • FIG. 14 shows a schematic diagram of the architecture of a vehicle.
  • the vehicle includes: a vehicle body, a vehicle processor 110, a gyroscope 120, a CAN transceiver 130, and a vehicle-mounted GPS 140.
  • the vehicle-mounted GPS 140, the gyroscope 130, and the CAN transceiver 130 are respectively connected to the vehicle processor 110, and respectively provide GPS data, angular velocity data, and vehicle speed data to the vehicle processor 110 to form a positioning system.
  • the vehicle processor 110 After receiving each data, the vehicle processor 110 performs DR calculation and corrects the vehicle speed when the correction condition is reached. This implementation is completely implemented inside the vehicle, avoiding the adverse effect of the communication delay with external mobile devices on the DR calculation result.
  • vehicle processor 110 may be one or more processing units or processing modules in the vehicle master controller, and it may be a separate processor or integrated into an existing processing device.
  • the vehicle processor 110 is specifically configured to perform DR calculation based on the GPS data, vehicle speed data, and angular velocity data collected or received, and to correct the vehicle speed when the correction condition is reached; and, the vehicle processor 110 is also used to output the DR estimation result when the GPS signal is poor.
  • the DR calculation result can be finally output to the display screen in the vehicle or the mobile device, for example, to the navigation display screen shown in FIG. 1B, so as to facilitate the user to understand the current driving position of the vehicle.
  • the DR calculation result can also be output to the navigation engine through the PVT bus, so that the navigation engine can navigate the road section for the vehicle according to the DR calculation result.
  • the processor involved in this application may include one or more processing units.
  • the processor may include an application processor (AP), a modem processor, and a graphics processing unit (GPU).
  • AP application processor
  • GPU graphics processing unit
  • ISP image signal processor
  • VPU video processing unit
  • DSP digital signal processor
  • NPU neural network processor
  • the different processing units may be independent devices or integrated in one or more processors.
  • the controller can be the nerve center and command center of the head-mounted electronic device.
  • the controller can generate operation control signals according to the instruction operation code and timing signals to complete the control of fetching and executing instructions.
  • a memory can also be provided in the processor to store instructions and data.
  • the memory in the processor is a cache memory.
  • the memory can store instructions or data that the processor has just used or recycled. If the processor needs to use the instruction or data again, it can be called directly from the memory. It avoids repeated access and reduces the waiting time of the processor, thus improving the efficiency of the system.
  • the DR calculation and the vehicle speed correction solution provided by this application can also be implemented in a mobile device connected to the vehicle. That is, the processor of the mobile device performs DR calculation, speed correction processing, route navigation processing, and the like.
  • the final recipient of the aforementioned data is the processor of the mobile device.
  • the aforementioned method can also be implemented cross-wise between the vehicle and the movable device.
  • the positioning system can be distributed on multiple devices. Specifically, among the first electronic device, the second electronic device, the third electronic device, the fourth electronic device, and the fifth electronic device, some of the electronic devices are mounted on the vehicle, and some of the electronic devices The device is mounted on a mobile device; wherein, some electronic devices mounted in the vehicle and some electronic devices mounted in the mobile device are communicatively connected.
  • the vehicle processor performs DR calculation and corrects the vehicle speed
  • the mobile device performs route navigation based on the DR calculation result.
  • the DR calculation is performed by the mobile device, but the vehicle speed is corrected by the vehicle.
  • the vehicle needs to establish a short-range communication connection with the mobile device.
  • the so-called short-range communication connection means that the mobile device and the vehicle can communicate through the short-range communication means, so that through the on-off of the communication relationship, it is judged whether the vehicle and the mobile device are in the same geographic location. It can be understood that if the vehicle and the mobile device can communicate normally in short distance, the positioning position collected by GPS in the mobile device can be used as the positioning position of the vehicle; otherwise, if the vehicle and the mobile device are in the preset second time range If there is no normal communication (for example, unable to receive the transmitted data), the positioning position collected by the GPS in the mobile device cannot be used as the positioning position of the vehicle.
  • the short-range communication connection methods involved in the embodiments of this application may include, but are not limited to: wireless local area networks (WLAN) (such as wireless fidelity (Wi-Fi) networks), Bluetooth (Bluetooth, BT) ), frequency modulation (FM), near field communication (NFC), infrared technology (infrared, IR) and other wireless communication solutions, as well as wired communication solutions.
  • WLAN wireless local area networks
  • Wi-Fi wireless fidelity
  • Bluetooth Bluetooth
  • FM frequency modulation
  • NFC near field communication
  • infrared technology infrared, IR
  • the movable devices involved in this application may include, but are not limited to: at least one of a terminal and a wearable device.
  • the terminal may be a wired terminal or a wireless terminal.
  • a wireless terminal may be a device that provides voice and/or other service data connectivity to a user, a handheld device with a wireless connection function, or other processing devices connected to a wireless modem.
  • a wireless terminal can communicate with one or more core network devices via a radio access network (RAN).
  • the wireless terminal can be a mobile terminal, such as a mobile phone (or “cellular” phone) and a mobile terminal.
  • Computers for example, can be portable, pocket-sized, handheld, computer-built or vehicle-mounted mobile devices, which exchange language and/or data with the wireless access network.
  • a wireless terminal can also be a personal communication service (PCS) phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a wireless local loop (Wireless Local Loop, WLL) station, and a personal digital phone.
  • PCS personal communication service
  • SIP Session Initiation Protocol
  • WLL wireless Local Loop
  • PDA Personal Digital Assistant
  • Wireless terminals can also be called systems, subscriber units (Subscriber Unit), subscriber stations (Subscriber Station), mobile stations (Mobile Station), mobile stations (Mobile), access terminals (Access terminal), user terminals (User Terminal), User Agent (User Agent) and User Equipment (User Device or User Equipment) are not limited here.
  • Wearable devices can be head-mounted devices or other portable devices.
  • the head-mounted device may be glasses, head-mounted electronic devices, goggles, and the like.
  • Other portable devices can be smart bracelets, smart watches, wearable headsets and other devices.
  • FIG. 15 shows a schematic diagram of the architecture of a positioning system including a vehicle and a mobile device.
  • a vehicle processor 110 a gyroscope 120, a CAN transceiver 130, and a vehicle-mounted GPS 140 are provided in the vehicle, and the vehicle processor 110 is communicatively connected with a movable device.
  • the vehicle processor 110 can obtain the angular velocity, vehicle speed, and GPS data from the gyroscope 120, the CAN transceiver 130, and the vehicle GPS 140. On this basis, the vehicle processor 110 and It is not used to directly implement the DR calculation and speed correction processing.
  • the vehicle processor 110 sends the angular velocity, vehicle speed, and GPS data to the mobile device, and the mobile device executes the DR calculation and speed correction processing.
  • This implementation method can be adapted to the user's need to realize vehicle positioning through portable terminals such as mobile phones and tablet computers.
  • the data for the DR calculation of the mobile device comes from the vehicle, which can also simplify the hardware structure and software logic of the mobile device to a certain extent, and can meet the portable needs of the mobile device.
  • FIG. 16 shows a schematic diagram of the architecture of a positioning system including a vehicle and a mobile device.
  • the vehicle is provided with a vehicle processor 110, a gyroscope 120, and a CAN transceiver 130
  • a mobile device is provided with a processor 210 and a GPS module 220, and the vehicle processor 110 and the processor 210 are close to each other.
  • Distance communication connection As shown in FIG. 16, the vehicle is provided with a vehicle processor 110, a gyroscope 120, and a CAN transceiver 130, and a mobile device is provided with a processor 210 and a GPS module 220, and the vehicle processor 110 and the processor 210 are close to each other. Distance communication connection.
  • the vehicle processor 110 may perform DR calculation and speed correction processing.
  • the processor 210 receives the GPS message or data output by the GPS module 220, it forwards it to the vehicle processor 110 through a short-range communication connection.
  • the GPS module 220 outputs a GPS message
  • the GPS message may also be parsed at the processor 210, and the processor 210 sends the parsed GPS data to the vehicle processor 110.
  • the vehicle processor 110 may also obtain angular velocity data collected by the gyroscope 120, obtain vehicle velocity data from the CAN transceiver 130, and then perform DR calculation and velocity correction processing.
  • the processor 210 may perform DR calculation and speed correction processing.
  • the processor 210 receives the GPS message or GPS data output by the GPS module 220.
  • the vehicle processor 110 obtains the angular velocity data collected by the gyroscope 120, and obtains the vehicle velocity data from the CAN transceiver 130, and sends the angular velocity data and the vehicle velocity data to the processor 210 in the mobile device. 210 performs DR estimation and speed correction processing.
  • Figure 17 shows a data interaction process of this implementation: the processor 210 in the mobile device acquires (or receives) GPS data, angular velocity and vehicle speed, and based on this Perform DR calculation.
  • the speed compensation factor for DR positioning is obtained, and the speed compensation factor is used to modify the vehicle speed used in the DR calculation process.
  • the processor 210 also sends the acquired speed compensation factor to the vehicle processor 110, and the vehicle processor 110 corrects the vehicle speed recorded and/or displayed in the vehicle, for example, the vehicle speed in the dashboard mounted on the vehicle.
  • the vehicle speed shown in the table is updated.
  • the mobile device may also perform route navigation according to the DR calculation result.
  • FIG. 18 shows a schematic structural diagram of another positioning system including a vehicle and a movable device.
  • a vehicle processor 110 and a CAN transceiver 130 are provided in the vehicle, and a processor 210, a gyroscope 230, and a GPS module 220 are provided in the mobile device, and the vehicle processor 110 and the processor 210 are close to each other.
  • Distance communication connection After the vehicle processor 110 obtains the vehicle speed through the CAN transceiver 130, it sends it to the processor 210 in the mobile device through the short-range communication connection.
  • the processor 210 obtains the angular velocity from the gyroscope 230 and the GPS data from the GPS module 220, and Carry out DR estimation and vehicle speed correction processing.
  • the number of movable devices connected to the vehicle is not particularly limited. Specifically, the number of movable devices may be at least one. For example, there may be only one movable device in the positioning system as shown in the scenarios shown in FIG. 15 to FIG. 18; or, the number of movable devices may also be more than one.
  • Figure 19 shows a possible situation.
  • the positioning system includes: a vehicle, a first movable device, and a second movable device.
  • the first movable device includes a gyroscope 230 and a processor 210, wherein the processor 210 is connected to the vehicle processor 110 in short-range communication
  • the second movable device includes a processor 310 and a GPS module 320, wherein the processor 310 It is connected to the vehicle processor 110 for short-distance communication.
  • the DR estimation method and its vehicle speed correction processing can be implemented in the vehicle processor 110.
  • the vehicle processor 110 obtains the angular velocity collected by the gyroscope 230 through the processor 210, and processes
  • the device 310 obtains GPS data recorded by the GPS module 320.
  • the DR estimation method and the correction processing of the vehicle speed can be implemented in at least one movable device.
  • the vehicle processor 110 serves as a bridge for data interaction between the first movable device and the second movable device, and is used to forward the vehicle speed and other received data.
  • any data interaction method can be designed between the vehicle, the first movable device, and the second movable device.
  • the embodiments of the present application also provide a computer-readable storage medium that stores instructions in the computer-readable storage medium.
  • the instructions run on an electronic device, the electronic device executes any of the foregoing implementations. The method described in the example.
  • the embodiments of the present application also provide a computer program product, which when the computer program product runs on an electronic device, causes the electronic device to execute the method described in any of the foregoing embodiments.
  • the computer may be implemented in whole or in part by software, hardware, firmware, or any combination thereof.
  • software it can be implemented in the form of a computer program product in whole or in part.
  • the computer program product includes one or more computer instructions.
  • the computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices.
  • the computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium.
  • the computer instructions may be transmitted from a website, computer, server, or data center.
  • the computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server or a data center integrated with one or more available media.
  • the usable medium may be a magnetic medium, (for example, a floppy disk, a hard disk, and a magnetic tape), an optical medium (for example, a DVD), or a semiconductor medium (for example, a solid state disk).

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Abstract

一种定位方法与系统、电子设备、车辆与存储介质，该方法包括：当车辆在第一环境中行驶时，显示卫星定位系统定位的第一车辆位置，第一环境的卫星信号质量满足预设质量要求（S302）；当车辆在第二环境中行驶时，显示第二车辆位置，第二环境的卫星信号质量不满足预设质量要求，其中，第二车辆位置是利用第一车辆速度推算得到的，第一车辆速度是利用卫星定位位置与航位推算位置对第二车辆速度修正得到的，第二车辆速度为车辆在行驶过程中获取到的速度（S304）。该方法降低了DR推算的累积里程误差，提高了DR推算结果的精度。

Description

定位方法与系统、电子设备、车辆与存储介质
本申请要求于2019年08月30日提交中国专利局、申请号为201910819085.9、申请名称为“定位方法与系统、电子设备、车辆与存储介质”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本申请涉及智能交通技术领域，尤其涉及一种定位方法与系统、电子设备、车辆与存储介质。
背景技术
为了提高行车效率、经济性，车载组合导航系统越来越普遍的安装于各类车辆。由于全球定位系统(Global Positioning System，GPS)等卫星定位系统在隧道、丛林、高楼区域等容易受到无线信号遮挡、多径干扰等因素的影响，无法定位车辆或定位准确率较低，因此，一般还会在车辆中搭载航位推算(Dead Reckoning，DR)处理器，以在GPS信号质量较差时利用DR推算来定位车辆位置。
DR推算是根据上一个位置来推算当前位置的，具体而言，DR推算是根据车辆速度与车辆角速度，获取车辆距离上一个位置的位移与航向，并结合上一个位置，推算出车辆的当前位置的。而车辆速度经常会由于轮胎磨损、气压变化、温度变化等原因，与车辆的实际速度存在误差，这也会进一步导致DR推算的车辆位置与车辆实际位置之间产生误差，这些位置误差会不断累积，随着行驶里程的增大而不断增大。
发明内容
本申请提供一种定位方法与系统、电子设备、车辆与存储介质，以期降低DR推算的累积里程误差，提高DR推算结果的精度。
第一方面，本申请提供了一种定位方法，包括：当车辆在第一环境中行驶时，显示卫星定位系统定位的第一车辆位置，所述第一环境的卫星信号质量满足预设质量要求；当所述车辆在第二环境中行驶时，显示第二车辆位置，所述第二环境的卫星信号质量不满足所述预设质量要求；其中，所述第二车辆位置是利用第一车辆速度推算得到的，所述第一车辆速度是利用卫星定位位置与航位推算位置对第二车辆速度修正得到的，所述第二车辆速度为所述车辆在行驶过程中获取到的速度。
如此，当车辆在卫星信号质量较好的第一环境中行驶时，利用卫星定位数据为用户定位和导航；而当车辆在卫星信号较差的第二环境中行驶时，则利用DR推算来定位车辆位置，并且，本申请实施例通过修正后的车辆速度推算车辆位置，有利于降低由于车辆速度导致的累积里程误差，提高DR推算结果的精度。
在第一方面的一种可能的设计中，所述第一车辆速度，是利用速度补偿因子修正所述第二车辆速度得到的，所述速度补偿因子是根据所述卫星定位位置与所述航位推算位置获取到的。如此，利用卫星定位位置与航位推算位置来获取速度补偿因子，进而修正车辆速 度，相对于利用GPS速度来修正车辆速度的方式，避免了速度的瞬时性对修正过程的不利影响，有利于得到误差更小的修正结果，进而也有利于降低DR推算结果的误差。
在第一方面的另一种可能的设计中，所述速度补偿因子，是在满足预设的修正条件时，根据所述卫星定位位置与所述航位推算位置获取到的。其中，所述修正条件至少包括：所述卫星信号质量满足所述预设质量要求。如此，在卫星信号质量较好的时候，才能够获取到较为准确的卫星定位位置，进而得到更准确的速度补偿因子，有利于降低误差。
其中，所述预设质量要求包括：卫星处于有效定位状态；卫星的水平精度因子小于或者等于预设的精度阈值；处于有效定位状态的卫星数目大于或者等于预设的第一数目阈值；信号强度大于或者等于预设的强度阈值的卫星，其总数大于或者等于预设的第二数目阈值。
在第一方面的另一种可能的设计中，所述卫星信号质量满足所述预设质量要求可以包括两种方式：第一种是所述卫星信号在预设的连续时长范围内，均满足所述预设质量要求；此时，卫星信号质量较好，且比较稳定，有利于得到更准确的卫星定位数据。而第二种是所述卫星信号瞬时即满足所述预设质量要求；此时，卫星信号短时较好，也能够实现卫星定位，但相较于前一方式，这种方式涵盖的卫星信号质量较好的范围更广，但卫星信号可能存在不稳定的情况。如此，可以通过预设质量要求来调整对卫星信号质量较好的要求，也能够实现对修正条件的调整。
在第一方面的另一种可能的设计中，所述修正条件还包括如下至少一种：从所述航位推算的起始点开始，所述车辆的行驶里程达到预设的距离阈值；所述航位推算位置与所述卫星定位位置之间的里程差大于预设的误差阈值；从所述航位推算的所述起始点开始，所述车辆满足预设的直行条件。其中，所述直行条件包括：从所述起始点开始，所述车辆的航向角的变化量小于或等于预设角度；或者，所述车辆从所述起始点开始在直行道路上单向行驶。如此，能够避免频繁修正车辆速度的情况，有利于降低计算资源的消耗；而直行条件也能够在一定程度上保证本方案能达到较好的DR推算准确率。
具体而言，可以获取所述卫星定位位置与所述航位推算位置之间的里程差；其中，所述卫星定位位置与所述航位推算位置相对应；然后，获取所述里程差与耗时时长之间的比值，得到所述速度补偿因子；其中，所述耗时时长为所述航位推算的起始点至所述航位推算位置之间花费的时长。
在得到速度补偿因子后，获取所述速度补偿因子与所述第二车辆速度之和，得到所述第一车辆速度；其中，在所述车辆的行驶方向上，若所述航位推算位置落在所述卫星定位位置的前方，所述速度补偿因子为负值；或者，在所述车辆的行驶方向上，若所述航位推算位置落在所述卫星定位位置的后方，所述速度补偿因子为正值。如此，通过速度补偿因子的修正，能够使得DR推算所使用的第一车辆速度更接近车辆的实际行驶速度，有利于降低误差，提高推算准确率。
在第一方面的另一种可能的设计中，所述航位推算位置是从起始点开始依次推算得到的；所述起始点，是在满足预设的起始条件时，获取到的所述卫星定位位置。
在第一方面的另一种可能的设计中，所述起始点，是在满足预设的起始更新条件，且满足所述预设的起始条件时，获取到的所述卫星定位位置。
其中，所述起始条件包括：满足所述车辆速度达到预设的起始速度阈值，与所述车辆的行驶里程达到预设的起始里程阈值中的至少一个；所述卫星信号质量满足所述预设质量 要求；所述车辆的航行稳定。
其中，所述起始更新条件，包括如下至少一种：所述航位推算的推算次数达到预设的次数阈值；从所述起始点开始，所述车辆的行驶里程达到预设的距离阈值；所述卫星定位位置与所述航位推算位置之间的里程差大于预设的误差阈值；所述车辆的航向角的变化量大于预设角度；满足预设的修正条件。
具体而言，所述航向角是由车辆的角速度处理得到的。
在第一方面的另一种可能的设计中，所述第二车辆速度由第一电子设备采集得到，所述卫星定位位置由第二电子设备采集得到，所述车辆的角速度由第三电子设备采集得到，所述第一车辆速度在第四电子设备中修正得到，所述航位推算位置在第五电子设备中推算得到；所述第一电子设备、所述第二电子设备、所述第三电子设备、所述第四电子设备与所述第五电子设备中，任意两种电子设备为同一电子设备，或者不同电子设备。
在第一方面的另一种可能的设计中，所述第一电子设备、所述第二电子设备、所述第三电子设备、所述第四电子设备与所述第五电子设备，都搭载于所述车辆中。此时，无需与外部设备通信，可直接在车辆中实现本方案。
在第一方面的另一种可能的设计中，所述第一电子设备、所述第二电子设备、所述第三电子设备、所述第四电子设备与所述第五电子设备中，部分电子设备搭载于所述车辆，部分电子设备搭载于可移动设备；其中，搭载于所述车辆中的部分电子设备与搭载于所述可移动设备中的部分电子设备，通信连接。所述可移动设备的数目为至少一个。这能够满足用户坐在车里，用手机等可移动设备来进行定位导航的情况，能够适应用户的多种应用场景，灵活性较高。
在第一方面的另一种可能的设计中，所述第一电子设备为速度采集装置、所述车辆总线或者车辆的速度表；所述第二电子设备为卫星信号接收装置；所述第三电子设备为陀螺仪；所述第四电子设备与所述第五电子设备为车辆处理器。
在第一方面的另一种可能的设计中，所述卫星信号包括：全球定位系统GPS卫星信号、北斗卫星导航系统卫星信号、格洛纳斯卫星导航系统GLONASS卫星信号或者伽利略卫星导航系统卫星信号。
第二方面，本申请提供了一种电子设备，包括：一个或多个处理器；一个或多个存储器；一个或多个传感器；以及一个或多个计算机程序，其中所述一个或多个计算机程序被存储在所述一个或多个存储器中，所述一个或多个计算机程序包括指令，当所述指令被所述电子设备执行时，使得所述电子设备执行如第一方面任一实现方式所述的方法。
第三方面，本申请提供了一种定位系统，包括：第一电子设备，用于采集并输出第二车辆速度；第二电子设备，用于接收并输出卫星定位数据；第三电子设备，用于采集并输出车辆的角速度；第四电子设备，用于执行如第一方面任一实现方式所述的方法。
第四方面，本申请提供了一种车辆，包括：车辆主体，以及，如第二方面所述的电子设备，或者，如第三方面所述的定位系统。
第五方面，本申请提供了一种计算机可读存储介质，所述计算机可读存储介质中存储有指令，当所述指令在电子设备上运行时，使得所述电子设备执行如第一方面任一实现方式所述的方法。
第六方面，本申请提供了一种计算机程序产品，当计算机程序产品在电子设备上运行 时，使得电子设备执行如如第一方面任一实现方式所述的方法。
综上，本申请所提供的一种定位方法与系统、电子设备、车辆与存储介质，能够降低DR推算的累积里程误差，提高了DR推算结果的精度，定位导航体验较好。
附图说明
图1A为本申请中DR推算位置与车辆实际位置之间的一种误差情况示意图；
图1B为本申请中DR推算位置与车辆实际位置之间的另一种误差情况示意图；
图2为本申请所提供的一种定位方式的示意图；
图3为本申请所提供的一种定位方法的流程示意图；
图4为本申请所提供的一种DR推算位置与GPS定位位置的示意图；
图5A为本申请所提供的一种定位方法的场景及误差情况示意图；
图5B为本申请所提供的另一种定位方法的场景及误差情况示意图；
图6A为本申请所提供的另一种定位方法的场景及误差情况示意图；
图6B为本申请所提供的另一种定位方法的场景及误差情况示意图；
图6C为本申请所提供的另一种定位方法的场景及误差情况示意图；
图7A为本申请所提供的另一种定位方法的误差情况示意图；
图7B为本申请所提供的另一种定位方法的误差情况示意图；
图7C为本申请所提供的另一种定位方法的误差情况示意图；
图8A为本申请所提供的另一种定位方法的误差情况示意图；
图8B为本申请所提供的另一种定位方法的误差情况示意图；
图8C为本申请所提供的另一种定位方法的误差情况示意图；
图9A为本申请所提供的另一种定位方法的起步场景示意图；
图9B为本申请所提供的另一种定位方法的起步场景示意图；
图9C为本申请所提供的另一种定位方法的起步场景示意图；
图9D为本申请所提供的另一种定位方法的起步场景示意图；
图10为本申请所提供的另一种定位方法的场景示意图；
图11为本申请所提供的另一种定位方法的场景示意图；
图12为本申请所提供的另一种定位方法的掉头场景示意图；
图13A为本申请所提供的另一种定位方法的变道场景示意图；
图13B为本申请所提供的另一种定位方法的变道场景示意图；
图14为本申请所提供的一种车辆的系统架构示意图；
图15为本申请所提供的另一种定位系统的架构示意图；
图16为本申请所提供的另一种定位系统的架构示意图；
图17为本申请所提供的另一种定位系统的数据交互示意图；
图18为本申请所提供的另一种定位系统的架构示意图；
图19为本申请所提供的另一种定位系统的架构示意图。
具体实施方式
下面结合本申请实施例中的附图对本申请实施例进行描述。
首先对DR推算过程进行简单说明。DR推算是根据上一个位置来推算当前位置的。具体的，DR推算是根据车辆速度与车辆角速度，获取车辆距离上一个位置的位移与航向，并结合上一个位置，推算出车辆的当前位置的。
将DR推算的起始位置记为P 0(Long 0,Lat 0)，起始航向记为Heading 0，DR推算的第1个位置记为P 1(Long 1,Lat 1)，其航向记为Heading 1，DR推算的第n个位置记为P n(Long n,Lat n)，其航向记为Heading n。并且，V i为第i推算时车辆速度，因此，将第n次采集得到的车辆的速度记为V n，将第n-1次采集得到的车辆的速度记为V n-1，而车辆在由V n-1与V n之间转过的角度记为θ n，其中，θ n与车辆第n次采集得到的车辆的角速度ω n、V n-1与V n之间的车辆行驶时间t相关。ω i为第i次DR推算时车辆的角速度，ω i有正负之分，其单位为度/秒，t为获取角速度的时间间隔，其单位为秒；为了便于处理，假设任意两次数据采集过程之间的时间间隔t是固定且相等的。n为大于0的整数。
DR推算时，根据P 0与车辆速度、车辆角速度来推算第一个DR推算位置P 1。此时，P 1(Long 1,Lat 1)与该位置的航向Heading 1可以表示为：
Heading 1＝Heading 0+ω 1t
Figure PCTCN2020111222-appb-000001
Figure PCTCN2020111222-appb-000002
DR推算继续进行，根据第一个DR推算位置P 1推算第二个DR推算位置P 2。具体的，根据P 1、车辆速度、车辆角速度来推算P 2，此时，P 2(Long 2,Lat 2)与该位置的航向Heading 2可以表示为：
Heading 2＝Heading 1+ω 2t
Figure PCTCN2020111222-appb-000003
Figure PCTCN2020111222-appb-000004
DR推算继续进行，根据第n-1个DR推算位置P n-1推算第n个DR推算位置P n。此时，P n(Long n,Lat n)与该位置的航向Heading n可以表示为：
Heading n＝Heading n-1+ω nt
Figure PCTCN2020111222-appb-000005
Figure PCTCN2020111222-appb-000006
基于前述DR推算过程，可知，车辆速度V i与角速度ω i是影响DR推算位置的主要因素。当车辆未发生转弯等情况，保持直行或近似直行的行驶状态时，角速度ω i对DR推算结果的影响较小，此时，对DR推算结果主要受到车辆速度V i的影响。可以理解，此处所涉及到的车辆速度是指DR推算过程中所使用的车辆速度。本申请实施例为便于说明，将DR推算过程中，所获取或采集到的车辆速度记为第二车辆速度。
具体而言，获取到的第二车辆速度会存在瞬时误差，而速度的瞬时误差会在DR推算过程中，以DR推算位置的误差方式进行累积，导致DR推算位置的误差越来越大。在任 意一次(假设第i次)DR推算过程中，车辆速度的误差会导致第i次DR推算位置与车辆实际位置产生误差，而第i次后的任意DR推算过程，又是以第i次的DR推算位置为基础继续进行的，也即，后续DR推算过程都会累积第i次DR推算位置的误差。例如，在第一次DR推算时，由于速度误差，导致第一次推算出的DR推算位置存在5m误差；那么，在此基础上继续推算，第二次DR推算时，由于速度存在瞬时误差，导致本次推算的DR推算位置存在3m误差，那实际上，DR推算位置与车辆实际位置之间会累积8m误差。
由此，车辆在道路上行驶了一段路程后，DR推算位置与车辆的实际位置之间的误差越来越大。此时，图1A和图1B以车辆直行为例，示出了DR推算位置与车辆实际位置之间的误差情况。
如图1A所示，由于DR速度存在误差，DR推算位置位于车辆实际位置的后方，DR推算位置位于路口2附近，而车辆的实际位置位于路口1附近。图1B则示出了图1A的具体场景。如图1B所示，车辆在道路上行驶，此时，车辆行驶到路口1附近。而该车辆中搭载的导航显示屏显示的是DR推算位置，此时，DR推算出车辆位于路口2附近。也即，DR速度误差导致了DR推算位置的定位偏差。进一步的，在如图1A、图1B所示场景中，若车辆在当前行驶位置(路口1处)发生右转，则车辆实际进入路口1，但车辆的DR推算位置位于路口2处，以DR推算位置进行路线导航时，则按照车辆进入路口2为车辆进行导航，这就会进一步引发定位丢失或地图匹配到其它错误道路等问题。
综上，在DR推算过程中，若DR速度有5％的误差，那么，车辆行驶1000米路程，DR推算位置会产生50米的误差；若DR速度有1％的误差，那么，车辆行驶1000米路程，DR推算位置会产生10米的误差。换言之，DR速度是DR推算位置准确度的关键因素。
其次，利用卫星定位具备较高的准确性，因此，在车辆行驶场景中，主要是利用卫星定位系统来定位车辆位置的，而DR推算定位方法一般作为卫星定位方法的辅助定位方式。这是由于卫星定位系统进行定位时依赖于卫星信号(或卫星定位信号)的传递，而卫星信号容易受到干扰。例如，在隧道、丛林、高楼等区域，卫星信号就容易受到遮挡、多径干扰等因素的影响。从而，在卫星信号被干扰的区域，就无法通过卫星定位方法进行定位，此时，就可以利用DR推算来定位车辆位置。
图2示出了这种情况。车辆在一条直行道路上行驶，且该道路上存在一段隧道，隧道处卫星信号被干扰。因此，如图2所示，在车辆进入隧道之前、车辆驶出隧道之后，均可以利用卫星定位方式来定位车辆位置；而在隧道内部，由于卫星信号被干扰，则利用DR推算车辆位置的方式，来定位车辆位置。
因此，在本申请的一种实施例中，在卫星信号较好的路段，例如图2所示的车辆驶入隧道之前、车辆驶出隧道之后的部分路段，可以在车辆的导航显示屏上显示卫星定位系统定位的第一车辆位置(卫星定位位置)；而在卫星信号较差的路段，例如图2所示的隧道路段，导航显示屏上则显示DR推算出来的车辆位置(DR推算位置，或航位推算位置)。换言之，在卫星信号较好的路段上，一般是通过卫星定位来推测车辆位置的，而在卫星信号受到干扰的路段，如高架桥、丛林、高楼区域、地下通道与图2所示的隧道中的至少一种，则通过DR推算来定位车辆位置。
此外，在卫星信号较好的路段上，卫星定位位置与车辆实际位置之间的误差较小，甚至可将卫星定位位置视作车辆的实际位置。
本申请所涉及到的卫星定位系统可以包括但不限于：全球定位系统(Global Positioning System，GPS)、北斗卫星导航系统(Beidou Navigation Satellite System，简称北斗或BDS)、格洛纳斯卫星导航系统(Global Navigation Satellite System，GLONASS)、伽利略卫星导航系统(Galileo satellite navigation system)等。为便于说明，后续以GPS为例进行说明。
需要说明的是，如图2所示的定位方式仅为一种示例性的实现方式，实际实现场景中，也可以完全利用DR定位方式来定位车辆位置。在本申请的另一个可能的实施例中，无论卫星信号是否较好，都可以利用DR推算来定位车辆位置。也即，本申请对在卫星信号较好的路段采用何种定位方式无特别限定。
基于此，在车辆直行的场景下，可以利用卫星信号较好时候的卫星定位位置(卫星定位方法定位出的车辆位置，例如，GPS定位位置，结合DR推算位置，来对DR速度进行修正，以在一定程度上降低由于DR速度误差引起的DR定位误差问题。
本申请实施例提供一种定位方法，可以参考图3，该定位方法可以按照如下方式实现：
S302，在当车辆在第一环境中行驶时，显示卫星定位系统定位的第一车辆位置，所述第一环境的卫星信号质量满足预设质量要求。
与图2所示实施例类似，此处仅为一种可能的实施例，在另一种实施例中，也可以在GPS信号较好，也即卫星信号质量较好的环境中，显示第二车辆位置。后续详述。
S304，当所述车辆在第二环境中行驶时，显示第二车辆位置，所述第二环境的卫星信号质量不满足所述预设质量要求；其中，所述第二车辆位置是利用第一车辆速度推算得到的，所述第一车辆速度是利用卫星定位位置与航位推算位置对第二车辆速度修正得到的，所述第二车辆速度为所述车辆在行驶过程中获取到的速度。
如图3所示，随着车辆行驶环境的变化，车辆的导航显示屏上可以显示不同手段定位得到的位置。若车辆由第一环境中驶入第二环境，则导航显示屏上显示的位置由第一车辆位置变更为第二车辆位置；反之，若车辆由第二环境中驶入第一环境，则导航显示屏上显示的位置由第二车辆位置变更为第一车辆位置。
本申请实施例中，第一环境与第二环境与卫星信号的质量有关，例如，图2中隧道里，由于卫星信号受到遮挡，而导致其不满足预设质量要求，隧道属于第二环境；反之，在隧道外，卫星信号质量较好，可以满足预设质量要求，隧道外属于第一环境。后续具体说明。
除此之外，还需要说明的是，本申请实施例中，第一车辆位置是卫星定位系统进行实时定位，而获取到的车辆的位置，而卫星定位位置是指当前时刻之前的、历史的卫星定位位置，二者不同。类似的，第二车辆位置是DR实时推算出来的车辆位置，而此处的航位推算位置是指当前时刻之前的、历史的DR推算位置，二者不同。
由此，可以利用之前的GPS定位位置和之前的DR推算位置的误差来修正第二车辆速度，用修证后的速度来进行航位推算。
现对该速度修正过程进行说明。
本申请的一种具体的实施例中，所述第一车辆速度，是利用速度补偿因子修正所述第二车辆速度得到的，所述速度补偿因子是根据所述卫星定位位置与所述航位推算位置获取到的。
具体实现时，从车辆位于起始点P 0时，开始进行DR推算，车辆向前直行前进了一段里程后，第n个DR推算出来的车辆位置记为P n。此时，GPS信号较好，可以获取到GPS 定位位置P Gn，如前所述，在GPS信号较好的时候，可以将GPS定位位置视作车辆的实际位置。因此，可以获取P Gn与P n之间的距离差，记为P GnP n。可以理解，P GnP n实际是由P 0开始至P n结束的一段行程内的速度误差导致的，因此，可以将车辆在这段行程内的位置误差平均到速度上，得到DR速度与车辆实际速度在这段行程内的速度误差情况。该速度误差情况可以用速度补偿因子δ表示，δ＝(P GnP n)/nt，其中，t表示DR推算过程的时间周期，nt表示由P 0到P n这段行驶里程所花费的时长。可以理解，在继续进行第n+1次DR推算时，就可以利用速度补偿因子δ来修正获取到的第二车辆速度V vehicle，得到第一车辆速度V。
基于此，在后续修正车辆速度时，可以获取第二车辆速度V vehicle与该速度补偿因子δ之和，以作为修正后的第一车辆速度V，也就是：V＝V vehicle+δ。如此，进行后续的DR推算时，就可以采用修正后的第一车辆速度V来进行推算。
本申请实施例中，第二车辆速度V vehicle是实时获取到的车辆速度，因此，在DR推算过程中，在获取到实时的第二车辆速度后，可以直接利用速度补偿因子进行实时修正，得到实时的第一车辆速度，并利用第一车辆速度来实时进行DR推算。其中，速度补偿因子可以是当前获取到的，或者，也可以之前获取并记录下来的。
可以理解，基于P Gn与P n之间的前后关系，速度补偿因子δ存在正负之分。
若GPS定位位置P Gn在DR推算位置P n的前方，也即，航位推算位置落在所述卫星定位位置的后方，则说明DR推算过程所采用的车辆速度比实际的车辆速度慢，因此，获取到的速度补偿因子δ为正值，后续修正车辆速度时，修正后的车辆速度V大于采集到的车辆速度V vehicle。
图4示出了一种P Gn与P n之间关系。图4中，P n(Long n,Lat n)为车辆经过一段行驶里程后，利用DR推算出来的车辆位置的经纬度表示，P Gn(Long G,Lat G)为与P n对应的GPS所定位的车辆位置，Heading n为第n个DR推算位置的航向，α表示P n与P Gn形成的方向角，θ表示α与Heading n之间的夹角。图4中，方向角α可以根据P Gn为与P n的坐标获取得到：
Figure PCTCN2020111222-appb-000007
基于此，根据DR航向Heading n与方向角α，可以得到夹角θ的表达式：θ＝abs(α-Heading n)，abs表示取绝对值；或者，若abs(α-Heading n)大于180度，则θ＝360-abs(α-Heading n)。此时，速度补偿因子δ可以表示为：
Figure PCTCN2020111222-appb-000008
反之，若DR推算位置P n在GPS定位位置P Gn的前方，也即，航位推算位置落在所述卫星定位位置的前方，则说明DR推算过程所采用的车辆速度比实际的车辆速度快，因此，获取到的速度补偿因子δ为负值，后续修正车辆速度时，修正后的车辆速度V小于采集到的车辆速度V vehicle。
在这种实现方式中，θ＝abs(α-(Heading n+180)％360)；或者，若abs(α-(Heading n+180)％360)大于180度，则θ＝360-abs(α-(Heading n+180)％360)。 速度补偿因子的表达式不再赘述。
本申请实施例中，速度补偿因子，是在满足预设的修正条件时，根据所述卫星定位位置与所述航位推算位置获取到的。
由此，在卫星信号较好的时候，获取速度补偿因子δ。因此，本申请实施例中，预设的修正条件至少可以包括但不限于：所述卫星信号质量满足所述预设质量要求。
本申请实施例中，卫星信号除直接来自于卫星之外，还可以通过地面基站中转，或者，还可以与地面基站信号配合。
仍以卫星信号为GPS信号为例。
GPS信号是否较好，是在能够接收到GPS信号的前提下来确定的，可以理解，若无法接收到GPS信号，则GPS信号必然较差，也无法满足预设质量要求。由此，本申请的一种实施例中，可以从卫星数目、定位精度、信号强度中的至少一个方面，来确定GPS信号质量的优劣。
一种具体的实现场景中，预设质量要求可以包括但不限于以下条件：
卫星处于有效定位状态；
卫星的水平精度因子小于或者等于预设的精度阈值；
处于有效定位状态的卫星数目大于或者等于预设的第一数目阈值；
信号强度大于或者等于预设的强度阈值的卫星，其总数大于或者等于预设的第二数目阈值。
前述条件中所涉及到的各阈值可以根据实际场景进行预设。例如，精度阈值可以预设为1.5，又例如，第一数目阈值可以预设为5，第二数目阈值可以预设为4，又例如，强度阈值可以预设为35db。
或者，在其他实现场景中，除满足前述4个条件才确定GPS信号较好的实现方式之外，还可以预设为：满足其中的至少一个(或者至少两个、或者至少三个)条件，就确定GPS信号较好。也就是，在实际场景中，预设质量要求可以根据实际场景自定义设计。
实际实现场景中，GPS接收模块可以接收GPS卫星发送的GPS报文，并基于GPS报文中携带的数据与预设质量要求进行比对，以确定车辆当前处于GPS信号质量较好的第一环境，还是处于GPS信号质量较差的第二环境。
一种可能的实现场景中，GPS报文中携带的数据可以包括但不限于以下几种：推荐定位信息(Recommended Minimum Specific GPS/TRANSITData，RMC)报文、可见卫星信息(GPS Satellites in View，GSV)报文与GPS定位信息(Global Positioning System Fix Data，GGA)报文。其中，RMC报文中可以包括但不限于定位状态(有效定位或者无效定位)、纬度格式、纬度半球(北半球或南半球)、经度格式、经度半球(东经或西经)、地面航向等信息，GSV报文中可以包括但不限于：可见卫星的总数、信噪比等信息，GGA报文中可以包括但不限于水平精度因子(Horizontal Dilution of Precision，HDOP)等信息。
此外，本申请实施例中，还可以在持续时长方面，对预设质量要求作进一步限制。此时，卫星信号质量满足所述预设质量要求，可以包括但不限于如下设计方式：
一种可能的设计中，若所述卫星信号瞬时即满足所述预设质量要求，则只要卫星信号质量满足预设质量要求，就确定车辆处于第一环境中。
或者，
另一种可能的设计中，若所述卫星信号在预设的连续时长范围内，均满足所述预设质量要求，则确定卫星信号质量满足预设质量要求，车辆处于第一环境中。这种实现方式，相当于GPS信号在预设的连续时长范围内持续较好，才确定当前GPS信号质量较好，处于第一环境。其中，连续时长范围可以根据实际需要进行预设。例如，可以预设为连续5s内(或3s等)GPS信号都满足前述条件，则GPS信号短时较好，车辆处于第一环境中。这种处理方式更有利于保证获取到的卫星定位位置的准确性，从而也有利于提高由此得到的速度补偿因子的准确率，进而，有利于降低第二车辆位置的误差情况。
本申请实施例中，除前述卫星信号质量需要满足预设质量要求之外，修正条件还可以包括如下至少一种：
从所述航位推算的起始点开始，所述车辆的行驶里程达到预设的距离阈值；
所述航位推算位置与所述卫星定位位置之间的里程差大于预设的误差阈值；
从所述航位推算的所述起始点开始，所述车辆满足预设的直行条件。
其中，行驶里程和里程差的实现方式后续详述。
本申请实施例，是在车辆直行前进的场景中，在GPS信号较好的时候，对DR速度进行修正，由此，需要车辆满足直行条件。
本申请实施例中，所述直行条件可以包括但不限于：
从所述起始点开始，所述车辆的航向角的变化量小于或等于预设角度；或者，
所述车辆从所述起始点开始在直行道路上单向行驶。
一种可能的实现方式中，可以参考图4。图4中还进一步示出了两条辅助线：辅助线1与辅助线2，并且，辅助线1与辅助线2与Heading n之间的夹角θ(可视为航向角的变化量)为预设角度，例如10度或5度，预设角度用于指示车辆是否直行。其中，如前所述，车辆的航向角可以由车辆的角速度处理得到。
如图4所示，若夹角θ大于预设角度，则说明车辆DR航向发生偏转，车辆可能发生了拐弯或转向，此时，仅仅对车辆速度进行修正不足以完全解决DR推算的位置误差。因此，这种情况下，可以直接利用较好的GPS信号，来对DR推算的起始位置进行更新。
若夹角θ小于或者等于预设角度，例如图4中夹角θ在10度(或5度，自定义预设)范围内，则车辆的DR航向与车辆实际行驶航向误差不大，车辆仍然处于直行状态，此时，对车辆速度进行修正，就能够在一定程度上降低前述DR推算过程所累积的里程误差。
可以理解，若夹角θ为0，P Gn在P n的正前方，或者，P Gn在P n的正后方，此时，获取P GnP n时，可以根据P Gn与P n的坐标值，获取两点之间的距离即可。从而，若航向角的变化量θ不大于预设角度，确定车辆直行，满足前述预设的修正条件中的直行条件。
另一种可能的设计中，还可以进一步结合地图来判断车辆是否处于直行状态，也就是，判断所述车辆从所述起始点开始，是否在直行道路上单向行驶。
具体的，可以获取车辆所在区域的地图，从而，通过P n来定位车辆当前所在的道路，以及，车辆在所在道路中的位置。从而，根据所在道路的形状，确定所在道路是直道，还是弯道(或其他路况，仅举例)，那么，如所在道路为直道，则可以获取车辆在所在道路中的位置，与所在道路的弯道(或出口)之间的路线长度，若该路线长度大于预设的长度阈值，例如50米，则确定车辆在道路上直行；反之，若路线长度小于预设的长度阈值，则说明车辆可能要发生变道或进入弯道，则可视作车辆在道路上未直行。其中，长度阈值 的数目和数值都可以根据需要预设，不赘述。
因此，本申请实施例中，对车辆速度进行修正时，还可以按照前述方式对车辆是否处于直行状态进行确定，当确定车辆处于直行状态时，则采用本申请所提供的方式对DR速度进行修正。
此外，另一种可能的实现方式中，若车辆处于非直行状态，还可以利用车辆速度在行驶方向上的分量，来实现对DR速度的修正。但是，这种处理方式虽然也能够在一定程度上降低DR推算误差，但相较于车辆直行的情况，非直行情况下的DR推算误差仍较大。
现结合具体场景对本申请所提供的定位方法的实现方式进行说明。
图5A与图5B示出一种车辆行驶场景：车辆在一段直行路段上沿虚线箭头的方向由左向右直行的场景，在该直行路段上存在一段干扰路段，且在干扰路段上，GPS信号质量大幅下降。如图5A与图5B所示，本申请是在GPS信号较好的时候，GPS信号质量满足预设质量要求，且车辆直行，此时，满足预设的修正条件，此时可以获取速度补偿因子，从而，在后续的DR推算过程中，可以利用速度补偿因子，修正第二车辆速度，进而得到DR推算位置。
获取到速度补偿因子之后，针对第二车辆速度的修正是在DR推算过程中持续进行的，因此，图5A中表示为“修正车辆速度”，意指从该位置开始，修正车辆速度。例如图5A中，在进入干扰路段之前，就开始修正车辆速度，车辆在干扰路段中行驶的过程中，进行DR推算时，也一直在用速度补偿因子修正第二车辆速度，并利用修正后的第一车辆速度进行DR推算。
如图5A所示，车辆驶入干扰路段之前、车辆驶出干扰路段之后，以及车辆在无干扰路段上行驶了一段里程之后，均满足预设的修正条件(直行、GPS信号较好)，则在这三个位置，可以获取到当前位置的速度补偿因子，可以开始对车辆速度进行修正。图5A～图5B中示出了在获取到速度补偿因子后，就立即利用该速度补偿因子修正车辆速度的情况，可以理解，本申请并不限于这种处理方式，不再赘述。
具体而言，在图5A所示的修正点(标记了“修正车辆速度”的位置)处，开始修正第二车辆速度，并在后续的DR推算过程中，利用修正后的第一车辆速度进行DR推算。如前所述，速度修正所采用的速度补偿因子可以是根据修正点处对应的P Gn与P n，而实时计算得到的；或者，也可以是在此之前就已经计算得到的；或者，也可以是直接被记录存储好的。之后，可以在后续DR推算过程中，利用补偿因子来修正DR速度。也就是，针对DR速度的修正，是一个持续的处理过程，本申请后续附图及说明中所涉及到的“修正车辆速度”、“修正点”是表示速度修正过程的起点。由此，在本申请的一种实施例中，可以在图5A所示的修正车辆速度的修正点处获取DR定位的速度补偿因子，并从修正点开始修正DR速度。
可以理解，速度补偿因子是在满足预设的修正条件后，获取得到的；而针对第二车辆速度的修正，则可以在任意位置进行，也可以从任意一个位置作为修正起点，在后续的DR推算过程中持续进行。
在本申请的另一种实施例中，也可以仅在修正点处获取DR定位的速度补偿因子，但暂不修正DR速度。例如，车辆在GPS信号持续较好的路段上行驶，GPS信号一直较好，DR推算位置可以在后台进行推算，但并不用于显示在导航显示屏上(第一环境中，导航 显示屏显示第一车辆位置)，则可以在修正点处获取DR定位的速度补偿因子，而无需修正DR速度。又例如，若DR推算仅在第二环境中才开始运算，则可以提前在修正点处获取速度补偿因子，从而，当车辆驶入第二环境，就可以利用速度补偿因子，开始实时修正第二车辆速度，并用修正后的第一车辆速度来推算车辆位置。
在实际场景中，若GPS信号较好，除利用GPS定位数据进行本申请所示的速度修正方法之外，还可以进一步利用GPS定位数据来修正DR推算位置。而利用GPS定位数据修正DR推算位置，则可以直接在GPS信号较好的时候，获取GPS定位位置，并将GPS定位位置来替换掉DR推算位置即可。此时，导航显示屏上显示的车辆位置就由第二车辆位置变更为第一车辆位置。如果这两个位置差别较大，则导航显示屏上的车辆位置就由一个位置跳到另一个位置；但若这两个位置差别较小，导航显示屏上显示的车辆位置变化不大，用户可能是无感知的。具体场景中，当利用GPS定位位置来修正DR推算位置时，一般还可以将校正后的DR推算位置作为DR推算的起点。也就是，在修正DR推算位置后，就以当前修正点作为DR推算的起始点，开始进行下一轮DR推算。
可以参考图5A，图5A示出了在速度修正点处同时修正DR推算位置的场景示意图。本申请实施例中，将车辆的实际位置标记为11，而13则表示利用第一车辆速度进行DR推算得到的DR推算位置，而12则表示利用第二车辆速度进行DR推算得到的DR推算位置。相应的，曲线121表示未修正速度的DR推算位置12与车辆的实际位置11之间的第二误差曲线，第二误差曲线121的夹角记为第二误差夹角，以a进行表示；曲线131则表示修正DR速度的DR推算位置13与车辆的实际位置11之间的第一误差曲线，第一误差曲线131的夹角记为第一误差夹角，以b进行表示，b的标号用于区分，无实际意义，如图5A与图5B中的b1和b2。后续图示标识不变，不再额外说明。
在如图5A所示的实现场景中，由于在DR速度的修正点修正DR推算位置，那么，在任意一个速度修正点，未修正速度的DR推算位置12、修正速度后的DR推算位置13与车辆实际位置11重合，此时，第二误差曲线121与第一误差曲线131的值都最小。如图5所示，此处，若将GPS定位位置视作车辆实际位置，则第二误差曲线121与第一误差曲线131在修正点处为0。
随着车辆继续直行行驶，车辆驶入干扰路段，并在干扰路段中继续行驶，DR推算位置开始累积误差。如图5A所示，第二误差曲线121与第一误差曲线131的值都随着里程的增大而增大，也即第二误差与第一误差都随着里程的增大而增大。并且，如图5A所示，在任意一个位置，未修正速度的DR推算位置12与车辆实际位置11之间的偏差，都大于修正速度后的DR推算位置13与车辆实际位置11之间的偏差。换言之，第二误差曲线121的增长幅度大于第一误差曲线131的增长幅度，第二误差夹角a大于第一误差夹角b(包括b1与b2)。可以理解，通过在GPS信号较好的时候修正车辆速度，能够有效降低后续DR推算过程的位置误差。
除此之外，经过多次修正车辆速度，能够使得修正后的车辆速度越来越趋近车辆的真实速度，从而，降低DR所使用的车辆速度的误差，由此，也提高了DR推算结果的准确率。如图5A所示，在每一次校正DR推算位置之后，未修正速度的DR推算位置12与车辆实际位置11之间的第二误差的增长趋势是相同的，第二误差夹角a的夹角不变。这是由于，若仅在修正点处修正DR推算位置，而不对车辆速度进行修正，那么，在不考虑变量 的情况下，例如，不考虑速度误差可能不同、路况可能不同、轮胎磨损情况可能不同的情况，那么，由于车辆速度而导致的DR推算位置的误差是基本不变的。反之，如图5A所示，在DR推算过程中，若不断修正DR速度，那么，经过多次修正，DR速度越来越趋近车辆的实际速度，有利于进一步降低DR推算的位置误差。那么，本申请实施例中，随着速度修正过程的重复执行，DR推算位置的误差曲线(第一误差曲线131)的涨幅越来越小，如图5A所示，第一误差夹角b不断变小，上一次DR推算过程的第一误差夹角b1大于本次DR推算过程的第一误差夹角b2。
本申请除应用于在GPS信号较差的干扰路段修正DR速度，当车辆在GPS信号较好的路段上，仍然可以持续利用DR推算方式来定位车辆位置时，例如，图5A中车辆在第一环境中行驶过程中，仍然可以持续进行DR推算。此时，也仍然可以利用本申请所提供的速度修正方法来修正DR推算所使用的车辆速度(DR速度)。
在另一种实现场景中，也可以在修正点仅修正DR推算过程所使用的车辆速度。此时，针对DR推算位置的修正和更新则与DR速度修正点无关，针对DR推算位置的修正点可以自定义设计，例如，可以在车辆行驶一定里程后，例如1km后，GPS信号较好的时候，再对DR推算位置进行修正。针对DR推算起始点的修正和更新，后续具体说明。
如图5B所示的行驶场景与图5A所示场景相同，不作赘述。而在图5B所示的实现方式中未示出DR推算的起点，在车辆驶入干扰路段前的一段行程中，就已经开始进行DR推算。在未行驶到DR速度的图5B中的第一个修正点之前，第二误差曲线121与第一误差曲线131的值都随着里程的增大而增大，且二者的夹角a与b0相同。也即，此时未修正速度的DR推算位置12与车辆实际位置11之间的偏差，与修正速度后的DR推算位置13与车辆实际位置11之间的偏差相等。
车辆继续行驶，到达进入干扰路段前的第一个速度修正点(车辆直行且GPS信号较好)，由于修正了DR所使用的车辆速度，第一误差曲线131的值随着里程增加而增大的涨幅有所缓解，如图5B所示，第一误差夹角由b0降低为b1，修正速度后的DR推算位置13与车辆实际位置11之间的偏差有所增大，但增大幅度降低。而第二误差曲线121未修正车辆速度，涨幅不变，第二误差夹角仍为a，未修正速度的DR推算位置12与车辆实际位置11之间的偏差，仍按照a对应的涨幅持续增大。由此，如图5B所示，未修正速度的DR推算位置12与车辆实际位置11之间的偏差，大于，修正速度后的DR推算位置13与车辆实际位置11之间的偏差。并且，由于并未在该修正点处修正DR推算位置，此时，DR推算的位置误差不清零。之后，车辆行驶到干扰路段，并在驶出干扰路段后，再次修正车辆速度，则如图5B所示，第一误差夹角再次降低，由b1降低为b2；而第二误差曲线121的第二误差夹角仍保持a不变。未修正速度的DR推算位置12与修正速度后的DR推算位置13之间的偏差也逐步增大。之后，再在下一次速度修正点，第一误差夹角再次由b2降低为b3；第二误差夹角仍为a不变。
在如图5B所示的实现场景中，由于并未对DR推算位置进行修正，DR推算的位置误差持续增大。但是，通过对DR速度进行修正，能够有效降低DR推算的位置误差的涨幅，相较于为修正DR速度的实现方式，这也能够在一定程度上降低DR推算位置偏离车辆实际位置的偏离程度。
结合图5A与图5B可知，在DR推算过程中，速度的误差不会累积，而DR推算的里 程误差才会累积，因此，在修正车辆速度的同时，利用GPS数据校正DR推算起始点的位置，更有利于及时清空DR推算过程所累积的位置误差，有利于得到更加准确的DR推算结果。因此，相对于图5B所示方式，图5A所示出的修正方式能够得到误差更小的航位推算结果。
图6A～图6C示出了另一种车辆行驶场景：车辆在道路上直行前进，该道路中存在至少两个干扰路段，干扰路段的GPS信号质量较差，属于第二环境，因此，通过DR推算来定位车辆位置。如图6A～图6C所示，任意相邻的两个干扰路段之间存在部分GPS信号较好的路段。可以理解，实际场景中，至少两个干扰路段中，任意两个干扰路段造成GPS信号被干扰的原因可以相同或不同。例如，车辆在行驶过程中，经常遇到两段隧道距离比较接近的情况，两段隧道之间存在短暂的露天区域，形成多干扰路段。或者，又例如，车辆在林木茂盛的区域直线行驶时，会时不时地出现GPS信号被林木或高楼短暂遮挡的情况。或者，又例如车辆在城市中直线行驶，遇到立交桥导致GPS信号被短暂遮挡导致GPS信号较差，车辆在第二环境中行驶；待驶出立交桥后，GPS信号恢复良好，回到第一环境行驶；之后，又行驶到高楼较多的区域，由于多径效应的影响，导致GPS信号再次受到影响，又再次由第一环境进入第二环境。
针对这种行驶场景，则至少可以有图6A～图6C所示的几种处理方式。图6A～图6C中示出了在获取到速度补偿因子后，就立即利用该速度补偿因子修正车辆速度的情况，可以理解，本申请并不限于这种处理方式，不再赘述。
一种可能的实现中，可以参考图6A，在车辆驶入第一个干扰路段之前、两个干扰路段之间的路段、车辆驶出第二个干扰路段之后，GPS信号较好，车辆在第一环境中处于直行状态向前行驶，此时，均满足前述预设的修正条件，则在这三个修正点处，可以开始修正车辆速度。并且，如图6A所示，在速度修正点，还同时对DR推算位置进行了修正，也就是，将速度修正点作为DR推算的起始点，开始下一轮的DR推算。
如图6A所示，第二误差曲线121、第一误差曲线131的值都随着里程的增加而增大，误差增大；由于经过了速度修正，第一误差曲线131的涨幅小于第二误差曲线121的涨幅。换言之，在任意一个位置，未修正速度的DR推算位置12与车辆实际位置11之间的偏差，都大于修正速度后的DR推算位置13与车辆实际位置11之间的偏差。在图6A所示场景中，在速度修正点修正DR速度时，还进一步修正了DR推算位置，因此，速度修正点作为下一轮DR推算的起始点，DR推算的位置误差最小。并且，在图6A所示的误差曲线上，在多次DR推算过程中，若不修正DR速度，则未修正速度的DR推算位置12对应的第二误差夹角a保持不变，而修正速度的DR推算位置13对应的第一误差夹角b，则随着修正车辆速度的次数不断降低，如图6A所示，a大于b1，且b1大于b2，这说明，经过多次DR推算，能够使得DR推算结果的位置误差降低。
此外，针对道路中存在多个干扰路段的情况，还可以在多个干扰路段中执行暂停修正处理。其中，暂停修正处理可以包括但不限于：暂停修正车辆速度，和/或，暂停更新DR推算的起始点(也即暂停修正DR推算位置)。
示例性的，图6B示出了暂停修正车辆速度的情况。如图6B所示，在存在多个干扰路段的情况下，可以自车辆驶入干扰路段，就暂停修正DR速度，直至车辆完全驶出最后一个干扰路段，再对车辆速度进行修正。那么，相较于图6A所示场景，车辆在两个干扰路 段之间的无干扰路段暂停速度修正，此时，图6B中存在两个速度修正点。车辆到达第一个速度修正点修正车辆速度和DR推算位置，之后的DR推算过程中，第二误差曲线121与第一误差曲线131的值都随着里程的增大而增大。并且，车辆在两个干扰路段，以及，两个干扰路段之间的无干扰路段中行驶时，DR推算过程的增长幅度不变。而由于在进入干扰路段前，提前对DR速度进行了修正，因此，第二误差夹角a大于第一误差夹角b。直至车辆驶出最后一个干扰路段之后，GPS信号恢复良好，满足预设的修正条件，再次修正车辆速度。可以理解，在第二个速度修正点之后的DR推算过程中，第一误差夹角b降低，而第二误差夹角a不变。
由于针对DR速度的修正，与针对DR推算位置的修正，可以不同步。那么，当在多个干扰路段暂停修正DR速度时，也可以不暂停DR推算位置的修正。换言之，还有一种可能的实现方式，也就是在两个干扰路段之间的无干扰路段，修正DR推算位置，在该位置修正点，DR推算的位置误差清零，但该位置修正点之后执行的DR推算过程中，由于未修正DR速度，因此，第二误差夹角a与第一误差夹角b均保持不变。直至车辆驶出最后一个干扰路段，满足预设的修正条件，修正DR速度之后，第一误差夹角b降低。
示例性的，图6C示出了暂停修正DR推算位置的情况。如图6C所示，在存在多个干扰路段的情况下，可以自车辆驶入干扰路段，就暂停更新DR推算的起始点，直至车辆驶出最后一个干扰路段，再对DR推算过程的起始点进行修正。也就是，待车辆驶出最后一个干扰路段，再利用GPS数据来修正车辆位置。
如前所述，针对DR速度的修正，与针对DR推算位置的修正，可以不同步。在图6C的场景中，在多个干扰路段之外的无干扰路段中，在速度修正点处同时修正DR推算位置，而在多个干扰路段之间，则暂停修正DR推算位置，当GPS信号较好时，满足预设的修正条件，就修正车辆速度。如图6C所示，经车辆速度修正后，第一误差夹角由b1降为b2，此时，修正速度后的DR推算位置13与车辆实际位置之间的偏差越来越大，但在该速度修正点之后，偏差的增长幅度有所缓解。直至车辆驶出最后一个干扰路段，GPS信号恢复良好，再利用GPS数据校正DR推算位置，并重新修正车辆速度。
需要说明的是，如图6B和6C所示的实现场景中，在实现时，就需要确定何时开始暂停修正处理(确定暂停处理起点)，以及，确定何时结束暂停修正处理(确定暂停处理终点)。
暂停处理起点，主要涉及车辆行驶前方的预设距离内是否出现多个干扰路段。具体而言，可以结合GPS定位位置与高精度地图，确定车辆行驶前方的路况。车辆在行驶过程中获取GPS定位位置，然后，将GPS定位位置与高精度地图进行匹配，匹配到车辆在高精度地图中的位置，之后，就可以根据高精度地图来确定道路前方的路况。
一种可能的设计中，可以确定车辆行驶前方是否出现隧道。若前方出现隧道，且隧道的数目为至少两个，那么，若任意相邻的两个隧道之间的无干扰路段的长度在预设的间隔阈值范围内，则确定这至少两个隧道是连续的，也就是，车辆行驶前方出现多干扰路段，开始执行暂停修正处理。
另一种可能的设计中，多个干扰路段可能是由高楼或林木等路边对象、立交桥、地下通道等路面建设对象造成的，此时，可以预先在高精度地图中对多个干扰路段进行标识。如此，将车辆GPS定位位置匹配到高精度地图上，若车辆行驶前方的预设距离内存在多个 干扰路段的标识，则车辆行驶前方出现多个干扰路段，开始执行暂停修正处理。
其中，预设距离可以根据需要预设。当预设距离较短时，可以在检测到车辆行驶前方存在多干扰路段时，就执行暂停修正处理；或者，当预设距离较长时，在检测到车辆行驶前方存在多干扰路段时，还可以持续根据GPS信号监控车辆与多干扰路段起点之间的距离差，若该距离差小于预设距离差时，也就是，车辆即将驶入多干扰路段时，开始执行暂停修正处理。
车辆后续进入多个干扰路段行驶过程中，存在GPS信号较好的露天路段，此时，可以结合高精度地图，确定车辆尚未驶出多干扰路段，则仍然保持暂停修正处理的状态。直至车辆能够接收到GPS信号，且其中的GPS定位位置指示车辆已经驶出多干扰路段，则暂停修正处理的过程终止，开始修正车辆速度，并校正DR推算位置与DR航向。
本申请的另一种设计中，车辆在道路上直行时，GPS信号较好(或短时较好)，在车辆行驶一段时间后存在较大的累积里程误差的时候，修正车辆速度。而本申请是利用车辆在一段行驶里程中累积的里程误差，来修正车辆速度的，那么，当车辆行驶里程较短时，DR推算的位置误差较小，对定位和导航的影响较小，无需在这种情况下进行速度修正。基于此，可以通过预设距离阈值和/或误差阈值的方式，对车辆所累积的累积里程误差进行限制，避免无必要的速度修正，节省系统资源。
一种可能的实现方式中，前述预设的修正条件还可以包括：从所述航位推算的起始点开始，所述车辆的行驶里程达到预设的距离阈值。具体实现时，可以获取当前位置与DR推算起始点之间的行驶里程，若该行驶里程大于或者等于预设的距离阈值，且GPS信号较好(或GPS信号短时较好)，就可以获取速度补偿因子，以修正车辆速度。
这种设计中，针对行驶里程与距离阈值的判断可以实时在后台执行，与GPS信号质量如何无关。此时，有一种可能的场景：当行驶里程等于预设的距离阈值时，车辆刚好在隧道里行驶，GPS信号质量较差，此时，继续行驶且暂不修正车辆速度，直至到GPS信号较好(或短时较好)的路段上，再修正车辆速度。
其中，距离阈值可以根据实际场景进行自定义设定。该数值可以是维护人员在出厂前设定好的，或者，也可以是用户可以自定义修改的，对此无特别限定。距离阈值可以是一个固定数值，例如，预设为1000米，无论车辆在何种路段上行驶，都按照该距离阈值进行处理。
图7A～图7C示出了这种情况。图7A～图7C中示出了在获取到速度补偿因子后，就立即利用该速度补偿因子修正车辆速度的情况，可以理解，本申请并不限于这种处理方式，不再赘述。
首先，可以参考图7A，其预设的距离阈值表示为S 2，且DR推算的起始点预设为速度的修正点。
如图7A所示，车辆开始行驶，将P 01作为第一次DR推算的起始点，开始进行DR推算，之后，DR推算过程所产生的误差随着里程的增大而增大。车辆继续行驶，直至与P 01之间的行驶距离达到S 2，此时，DR推算出第 n1个位置P n1，在该点修正车辆速度，同时校正DR推算的起始位置和起始航向，得到P 02。从P 02处开始进入第二轮DR推算过程，直至与P 02之间的行驶距离达到S 2。继续进行下一轮的速度修正和起始点校正。车辆行驶过程中，重复执行前述流程。经过前述速度修正处理，DR推算过程所产生的累积误差的增幅降低，误 差夹角(误差曲线与里程线之间的夹角)逐渐降低，如图7A所示，a＞b1＞b2＞b3。
其次，还可以参考图7B，此时，仍将预设的距离阈值表示为S 2，而DR推算的起始点按照预设的距离阈值(假设为S 3)循环实现。也就是，任意相邻的两次DR推算的起始点之间的距离为S 3。
如图7B所示，车辆行驶后，在P 01处开始第一次DR推算，车辆不断行驶且与P 01之间的行驶距离达到S 2，此时，DR推算出第 n1个位置P n1，在P n1处开始修正车辆速度，如图7B所示，修正车辆速度之后，DR推算的累积误差的增幅开始减缓，误差夹角由a降低到b1。由于未在P n1处更新DR的起始点，第一次DR推算的累积位置误差不清零，仍在原来位置误差的基础上继续累积，直至车辆与P 01之间的行驶距离达到S 3，在P 02处更新DR推算的起始点，此时，DR推算的位置误差清零。在进行后续的DR推算时，按照误差夹角为b1的方式，随着里程的增加而累积位置误差。之后，车辆行驶过程中，再重复执行前述流程。通过前述速度修正处理，DR推算过程所产生的累积误差的增幅降低，误差夹角也是逐渐降低，如图7A所示，a＞b1＞b2。
以及，还可以参考图7C，此时，仍将预设的距离阈值表示为S 2，DR推算过程，是按照每两个修正点对应一个起始点的情况实现的，也就是，在一个DR推算过程中，包含两个修正点，图7C中表示为P 02＝P n2。
如图7C所示，车辆行驶后，在P 01处开始第一次DR推算，车辆不断行驶且与P 01之间的行驶距离达到S 2，则在第 n1个位置P n1处开始修正车辆速度，修正车辆速度之后，DR推算的累积误差的增幅开始减缓，误差夹角由a降低到b1。之后，DR推算的位置误差继续累积，车辆继续行驶，且与P 01之间的行驶距离达到S 2，此时，在P 02处更新DR推算的起始点，并再一次修正车辆速度。从而，如图7C所示，DR推算的误差夹角由b1降低至b2。
除设计具体数值作为距离阈值之外，还可以基于各个路段上路况的不同，预设不同的距离阈值。例如，在GPS信号持续较好的无干扰路段，可以通过GPS数据直接对DR推算位置与DR航向进行校正，因此，无需频繁的修正车辆速度，此时，可以预设较长的距离阈值，以降低速度修正频率。又例如，针对高楼、立交桥较多的路段，则可以尽可能及时的修正车辆速度，以避免累积里程误差，此时，可以预设较短的距离阈值，来提高速度修正频率。
另一种可能的实现方式中，前述预设的修正条件还可以包括：所述航位推算位置与所述卫星定位位置之间的里程差大于预设的误差阈值。具体实现时，可以在GPS信号较好的路段上，获取GPS定位位置与DR推算位置之间的里程差，若该里程差大于或者等于预设的第二误差阈值，就可以获取速度补偿因子，以修正车辆速度。这种设计要求能够获取到GPS信号，是在获取到GPS定位位置后实现的，相较于前一设计，能够在一定程度上节省系统资源。
图8A～图8C示出了这种情况。图8A～图8C中示出了在获取到速度补偿因子后，就立即利用该速度补偿因子修正车辆速度的情况，可以理解，本申请并不限于这种处理方式，不再赘述。
首先，可以参考图8A，其预设的第二误差阈值表示为S 1，且DR推算的起始点预设为速度的修正点。
如图8A所示，车辆开始行驶，将P 01作为第一次DR推算的起始点，开始进行DR推算，之后，DR推算过程所产生的误差随着里程的增大而增大。车辆继续行驶，位置误差不断累 积直至达到S 1，此时，DR推算出第 n1个位置P n1，在该点修正车辆速度，同时校正DR推算的起始位置和起始航向，得到P 02。从P 02处开始进入第二轮DR推算过程，直至累积的里程误差再次达到S 1。继续进行下一轮的速度修正和起始点校正。车辆行驶过程中，重复执行前述流程。经过前述速度修正处理，DR推算过程所产生的累积误差的增幅降低，误差夹角(误差曲线与里程线之间的夹角)逐渐降低，如图8A所示，a＞b1＞b2。
其次，还可以参考图8B，此时，仍将预设的第二误差阈值表示为S 1，而DR推算的起始点按照预设的第二误差阈值(假设为S 3)循环实现。也就是，任意相邻的两次DR推算的起始点之间的距离为S 3。
如图8B所示，车辆行驶后，在P 01处开始第一次DR推算，位置误差不断累积直至达到S 1，此时，DR推算出第 n1个位置P n1，在P n1处开始修正车辆速度，如图8B所示，修正车辆速度之后，DR推算的累积误差的增幅开始减缓，误差夹角由a降低到b1。由于未在P n1处校正DR的起始点，第一次DR推算的累积位置误差不清零，仍在原来位置误差的基础上继续累积，直至达到P 02处。在P 02处更新DR推算的起始点，此时，DR推算的位置误差清零。在进行后续的DR推算时，按照误差夹角为b1的方式，随着里程的增加而累积位置误差。之后，车辆行驶过程中，再重复执行前述流程。并且，在如图8B所示的实现方式中，修正点与起始点之间的距离逐渐增大，后续可能会出现在一个DR推算过程中不进行速度修正的情况。
此外，还可以预设多个第二误差阈值。图8C中示出了预设两个第二误差阈值的情况。图8C中DR推算过程，是按照每两个修正点对应一个起始点的情况实现的，也就是，在一个DR推算过程中，包含两个修正点，图8C中表示为P 02＝P n2。
如图8C所示，车辆行驶后，在P 01处开始第一次DR推算，位置误差不断累积直至达到S 1，则在第 n1个位置P n1处开始修正车辆速度，修正车辆速度之后，DR推算的累积误差的增幅开始减缓，误差夹角由a降低到b1。之后，DR推算的位置误差继续累积，直至达到第二个第二误差阈值S 4，此时，更新DR推算的起始点，并再一次修正车辆速度，DR推算的误差夹角由b1降低至b2。
另一种可能的实现方式中，可以在GPS信号较好的路段上，按照前述方法获取当前位置的速度补偿因子，该速度补偿因子大于或者等于预设的第一误差阈值，则修正车辆速度。这种设计要求能够获取到GPS信号，是在获取到GPS定位位置后实现的，相较于前一设计，能够在一定程度上节省系统资源。
与距离阈值类似的，第二误差阈值、第一误差阈值也可以根据实际场景自定义设计，在此不赘述。
在车辆直行的场景中，当满足前述GPS信号条件(较好或短时较好)，或者，满足GPS信号条件之外，还进一步满足误差阈值和/或距离阈值条件的情况下，即可将当前DR推算位置P n作为车辆速度的修正点。
以图5A所示场景为例。车辆在行驶过程中，可以实时接收GPS报文，那么，可以仅满足GPS信号较好的要求，或者一些实现场景中还需要进一步满足预设的距离阈值和/或误差阈值的要求，就可以根据获取到的GPS数据来修正车辆速度。
例如，若针对车辆速度的修正可以是满足GPS短时较好(假设GPS信号持续2s都较好)且满足预设的距离阈值(假设行驶距离大于或者等于1km)的条件下实现的。此时，若车辆行驶到干扰路段，刚好行驶里程达到了1km，满足了预设的距离阈值，但干扰路段GPS 信号较差，则可以如图5A所示，在干扰路段暂时不修正车辆速度，直至车辆驶入无干扰路段，满足GPS信号持续2s都较好时，就立即修正车辆速度。
又例如，若针对车辆速度的修正可以是满足GPS短时较好(假设GPS信号持续2s都较好)且满足预设的距离阈值(假设行驶距离为1km的整倍数)的条件下实现的。此时，若车辆行驶到干扰路段，刚好行驶里程达到了1km，满足了预设的距离阈值，但干扰路段GPS信号较差，则可以如图5A所示，暂时不修正车辆速度。待车辆驶出干扰路段，车辆的行驶里程达到2km，再次检测GPS信号是否满足需求，若满足，则修正车辆速度；若不满足，则等行驶里程达到3km，再次检测GPS信号……直至车辆驶入无干扰路段，满足GPS信号持续2s都较好时，就立即修正车辆速度。
除此之外，DR推算过程中的预设的修正条件，还可以包括但不限于：DR推算位置与GPS定位位置能够对应。也就是，存在与当前DR推算数据相对应的同一时刻的GPS定位数据。
在实际实现场景中，该修正条件可以通过设置卫星报文的接收和输出频率、陀螺仪的采集频率以及DR推算的频率来实现。可知，主要设置的频率合适，该条件都可以实现对应。一种可能的设计中，若GPS模组通过RS232接口输出定位信息为NMEA格式电文，输出频率为1HZ或更高,输出数据速率为115200bps以上，GPS模组在有定位输出时同时输出时钟脉冲信号(Pulse Per Second，PPS)。而陀螺仪采集角速度数据的频率为40HZ。那么，预设的修正条件还需要满足：DR推算的次数n为40的整倍数，可以表示为n％40＝0。
除此之外，本申请是针对DR推算过程中所使用的车辆速度进行修正，对于任意一次DR推算过程而言，DR推算都是从起始点P 0开始，依次推算下一个位置的过程。现对DR推算的起始点P 0所要满足的起始条件进行说明。
本申请实施例中，所述航位推算位置是从起始点开始依次推算得到的，而所述起始点，是在满足预设的起始条件时，获取到的所述卫星定位位置。
也就是，对于任意一次DR推算，其起始点P 0都是在GPS信号较好的情况下，利用GPS数据校正得到的。换言之，DR推算的起始点P 0的起始条件至少满足：所述卫星信号质量满足所述预设质量要求。也就是，满足GPS信号较好(或短时较好)的条件。
若车辆处于GPS信号较差的路段，则无法在该路段中确定起始点或更新起始点，待车辆驶出该路段后，满足GPS较好的条件后，再确定或更新起始点。一种具体的实现场景中，可以通过GPS发送的时钟脉冲信号(Pulse Per Second，PPS)信号触发DR推算过程。
除此之外，考虑到车辆起步状态下，车辆速度很低，这种情况下，GPS定位位置与DR推算位置的位移在一开始是非常微小的，甚至可忽略不计，因此，若直接将车辆的起步点作为DR推算的第一个起始点，会在一定程度上带来推算误差。因此，可以从速度与里程至少一个方面对起始点进行限制，以避免起步情况下导致的误差。
具体的，DR推算的起始点P 0的起始条件还可以包括但不限于如下至少一个条件：
车辆速度达到预设的起始速度阈值；
车辆的行驶里程达到预设的起始里程阈值。
一种可能的实现场景中，若预设了起始速度阈值，那么，从车辆起步开始，就通过轮胎所转的圈数来获取车辆速度，当车辆速度达到预设的起始速度阈值，且当前GPS信号质量较好，就获取GPS定位位置以作为DR推算的起始位置，以及，获取GPS航向以作为 DR推算的起始航向，开始进行DR推算。
另一种可能的实现场景中，若预设了起始里程阈值，那么，从车辆起步开始，就通过轮胎所转的圈数来计算车辆起步后的行驶里程(或者，若GPS信号较好，也可以利用GPS数据来获取起步后的行驶里程)，当起步后的行驶里程达到预设的起始里程阈值，且当前GPS信号质量较好，就获取GPS定位位置以作为DR推算的起始位置，以及，获取GPS航向以作为DR推算的起始航向，开始进行DR推算。
除此之外，除起步后的行驶里程之外，行驶里程也可以是：从开始判断是否进行DR推算的时刻开始，到当前时刻的行驶里程。
此外，还可以结合前述两种方式，当车辆速度达到起始速度阈值、起步后的行驶里程达到预设的起始里程阈值，且当前GPS信号较好，就获取GPS定位位置以作为DR推算的起始位置，以及，获取GPS航向以作为DR推算的起始航向，开始进行DR推算。
其中，起始速度阈值、起始里程阈值可以根据实际需要预设。例如，起始速度阈值可以预设为5m/s。又例如，起始里程阈值可以预设为100米。
除此之外，考虑到车辆在实际行驶场景中，可能涉及到转弯、掉头等情况，这就导致车辆的行驶方向在较短的时间内发生较大变化，如此，DR推算的起始点P 0的起始条件，还可以包括：所述车辆的航行稳定。
所谓航向稳定，是指在预设的时长范围内，车辆航向角的变化量(如图4所示的夹角θ)小于预设角度。例如，车辆的航向角在连续5秒内的变化角度都小于3度，则车辆航向稳定。
在车辆刚刚起步开始行驶的场景中，从车辆起步开始就采集GPS数据、车辆速度数据、角速度数据，并基于这些数据，判断是否满足前述起始条件，若满足，则根据GPS数据确定出起始点P 0，并开始进行DR推算。
现结合图9A～图9D所示的车辆起步场景，对起始条件与预设的修正条件进行示例说明。示意性的，本申请附图中，将数据采集起点记为A，将数据采集终点记为B。
如图9A所示，车辆在无干扰路段上起步并继续行驶。在该场景中，车辆起步即开始采集数据，并基于采集到的数据开始判断是否满足前述起始条件，若满足，则开始进行DR推算。在开始进行DR推算后，就可以按照前述预设的修正条件来确定修正点。如图9A所示，在速度修正点，可以更新数据采集起点A，也就是，在该位置修正DR推算位置，开始进行下一轮的DR推算。预设的修正条件如前所述，若只涉及GPS较好的相关条件，则可以在DR推算后的任意位置修正车辆速度；或者，除GPS较好的相关条件外，还需要满足预设的距离阈值和/或误差阈值，当这些修正条件满足时，即可修正车辆速度，不赘述。
图9B与图9C示出了车辆在无干扰路段起步，并且，起步前方存在GPS信号较差的干扰路段的情况。如图9B所示，若车辆的起步点距离干扰路段入口较近，那么，在进入干扰路段前，可以暂时不采集数据，而是待车辆驶出干扰路段之后，开始采集数据。若采集到的数据满足预设的起始条件，就可以更新DR推算的起始点，并在满足前述预设的修正条件时，修正车辆速度。除此之外，若车辆的起步点距离干扰路段入口较近，导致在车辆进入隧道前，无法及时采集到GPS数据，那也就无法及时确定出DR推算的起始点。这种情况下，车辆起步进入隧道之前，无法获取到准确的DR推算起始点。此时，在车辆驶出干扰路段之前，有两种处理方式：一种是以车辆的起步点作为DR推算的起始点，进行 DR推算；另一种则是如图9B所示，在隧道中暂停DR推算，待车辆驶出干扰路段之后，再采集数据并确定DR推算的起始点。
如图9C所示，车辆起步，即开始采集数据。若车辆的起步点距离干扰路段的入口较远，车辆进入干扰路段前，有足够的时间利用GPS数据来获取到较为准确的DR推算起始点。此时，当车辆驶出隧道后，修正车辆速度，此时，可以将修正点作为数据采集终点，并重新校正DR推算位置的起始点。另外，相较于图9B所示情况，图9C所示场景中，由于在进入隧道前就开始DR推算过程，并开始累积推算误差，速度修正点相对于图9B所示情况更加靠近隧道出口。
图9D示出了车辆在干扰路段中起步，并逐渐驶入无干扰路段的场景。例如，车辆从地下车库中启动并直行驶出地下车库的情况；又例如，存在树林遮挡GPS信号的情况，车辆在树林中起步，并执行驶出树林区域的情况。在如图9D所示场景中，车辆在干扰区域无法获取到GPS信号，则无法获取到DR推算的起始点，无法进行DR推算。因此，待车辆驶出干扰区域后，即开始采集数据，并基于前述起始条件来确定DR推算的起始点，开始进行DR推算，并在满足预设的修正条件时，修正车辆速度。速度修正点可以作为数据采集过程的终点B，并更新数据采集的起点A。
但是，在车辆行驶到场景中，DR推算过程已经在后台实时推算处理，这就涉及到更新DR推算的起始点的问题。具体的，更新DR推算起始点，就是重新采集GPS数据、车辆速度数据、角速度数据，并基于这些数据，实时判断是否满足前述起始条件，若满足，则根据GPS数据更新起始点P 0，并以更新后的起始点开始进行后续道路的DR推算。
此时，航向推算的起始点是在满足预设的起始更新条件，且满足所述预设的起始条件时，获取到的所述卫星定位位置。
也就是说，在车辆行驶过程中，可以利用DR推算车辆位置，在该过程中，判断是否满足起始更新条件，若满足，则更新起始点；而更新起始点还需要满足前述起始条件，因此，这种情况下，DR推算的起始点需要同时满足起始更新条件与起始条件。起始条件如前所述，不作赘述。
而本申请实施例所涉及到的起始更新条件可以包括但不限于如下至少一种：
所述航位推算的推算次数达到预设的次数阈值；
从所述起始点开始，所述车辆的行驶里程达到预设的距离阈值；
所述卫星定位位置与所述航位推算位置之间的里程差大于预设的误差阈值；
所述车辆的航向角的变化量大于预设角度；
满足预设的修正条件(也即将修正点作为起始点，更新起始点位置)。
以下，详述。
一种可能的设计中，可以获取当前次DR推算的推算次数，若当前推算次数达到预设的次数阈值，DR推算结果的误差可能较大，则更新DR推算的起始点。
另一种可能的设计中，从所述起始点开始，所述车辆的行驶里程达到预设的距离阈值时，更新DR推算的起始点。例如，可以获取当前DR推算点与DR起始点之间的里程差，若该里程差达到预设的距离阈值，则DR推算结果的误差可能较大，更新DR推算的起始点。又例如，可以获取车辆的里程表中，获取从DR推算起始点至当前位置的累积行驶里程，从而，若该累积行驶里程达到预设的距离阈值，则DR推算结果的误差可能较大， 更新DR推算的起始点。
另一种可能的设计中，在当前DR推算位置与该点对应的GPS推算位置之间的误差值，若误差达到预设的误差阈值，则更新DR推算的起始点。这种情况下，修正点(开始修正车辆速度的起点)与更新后的起始点重合。
另一种可能的设计中，可以实时获取车辆的角速度，以获取车辆航向角的变化量，若航向角的变化量大于预设角度，则说明车辆发生了转向，则更新DR推算的起始点。
图10～图13B示出了几种更新DR推算起始点的情况。其中，更新DR推算的起始点，也就是，更新数据采集起点A。
如图10所示，车辆在T字形道路上行驶，该路段上GPS信号均较好。若车辆继续向前行驶，车辆的航向偏转情况较小，仍按照原来的行驶方向向前行驶，则无需更新DR推算的起始点。若车辆在T字形道路上继续向前行驶，但由于等红灯或其他原因，发生了短时停车等待的情况，由于车辆航向未发生变化，也无需更新DR推算起始点。其中，车辆短时停车区别于熄火，可以从车辆控制器中获取到车辆是否熄火的信息，在此不作详述。
若车辆右转，则在车辆转弯过程中，车辆的航向角发生较大偏转(航向角的变化量大于预设角度)，则更新DR推算的起始点。具体的，并重新采集GPS数据、车辆速度数据、角速度数据，实时判断这些数据是否满足前述起始条件。可知，在车辆转弯过程中，车辆航向不稳定，难以满足航向稳定条件。直至车辆转弯完成后，车辆航向稳定，此时，满足前述起始条件，就获取GPS定位位置、GPS航向以作为DR推算的起始点的数据，并开始进行后续的DR推算即可。
图11则示出了车辆在弯道上行驶的场景。车辆一开始在直行路上上行驶，之后，进入弯道，车辆的航向角发生较大偏转，此时可以更新DR推算的起始点。也就是，车辆航向角的变化量大于预设角度时，重新采集GPS数据、车辆速度数据、角速度数据，并实时判断是否满足前述起始条件。在车辆在弯道中行驶过程中，由于航向偏转较大，不满足起始条件。直至车辆驶出弯道，车辆的航向稳定，此时，满足了起始条件，就获取GPS定位位置、GPS航向以作为DR推算的起始点的数据，并开始进行后续的DR推算即可。
图12示出了车辆掉头的场景。车辆发生掉头，则更新DR推算的起始点，并且，DR推算的起始点是在车辆掉头后，车辆航向趋于稳定的情况下，满足起始条件，起始点更新成功。
另一种可能的设计中，考虑到出辆可能出现变道的情况，因此，可以预设一段缓冲区间，在该缓冲区间内，只要缓冲区间的起点与缓冲区间的终点之间的航向角的变化量在预设角度的范围内，就无需更新DR推算的起始点。其中，缓冲区间可以为时间区间，如一分钟内。缓冲区间也可以为里程区间，如50米内。
以时间区间为例，若车辆航向角发生偏转，以当前时刻为时间区间的起点，获取时间区间的终点处车辆的航向角，与时间区间起点处的航向角之间的变化量，若航向角的变化量在预设角度范围内，则无需更新DR推算的起始点；若航向角的变化量大于预设角度，则更新DR推算的起始点。
图13A与图13B示出了车辆变道的场景。在该场景中，车辆开始变道，航向角发生偏转，记为缓冲区间的起点。然后，车辆变道过程中，航向角持续发生变化，变化量可能大于预设角度。在缓冲区间的终点，判断当前航向角与缓冲区间起点处的航向角之间的变化 量与预设角度的关系。如图13A所示，若车辆在缓冲区间范围内完成变道，则航向角的变化量在预设角度范围内，无需更新DR推算的起始点；反之，如图13B所示，若车辆在缓冲区间范围内仍未完成变道，则航向角的变化量大于预设角度，在车辆变道后航向稳定的情况下更新DR推算的起始点。
需要说明的是，在前述设计中，若检测到车辆的航向角发生较大偏转(航向角的变化量大于预设角度)，则需要更新DR推算的起始点，本申请对车辆转弯情况下DR推算过程是否暂时停止无特别限定。在该过程中，可以暂停DR推算，或者，也可以继续进行DR推算，直至起始点更新。
此外，前述DR推算过程中，所涉及到的数据采集是指采集GPS数据、第二车辆速度与角速度。由此，在具体实现本方案时，所述第二车辆速度由第一电子设备采集得到，所述卫星定位位置(例如，GPS定位位置)由第二电子设备采集得到，所述车辆的角速度由第三电子设备采集得到，所述第一车辆速度在第四电子设备中修正得到，所述航位推算位置在第五电子设备中推算得到。并且，所述第一电子设备、所述第二电子设备、所述第三电子设备、所述第四电子设备与所述第五电子设备中，任意两种电子设备为同一电子设备，或者不同电子设备。
例如，第四电子设备与第五电子设备可以为同一个电子设备，该电子设备可以为车辆处理器。又例如，第四电子设备可以为车辆控制器，第五电子设备可以为航位推算处理器，航位推算处理器与车辆控制器独立。又例如，第四电子设备可以为手机处理器，第五电子设备可以为车辆控制器。
又例如，第一电子设备与第四电子设备可以为同一个电子设备，此时，第一电子设备在采集到第二车辆速度后，即可直接利用速度修正因子来修正第二车辆速度，此时，第一电子设备输出的数据，即为已经修正后的第第一车辆速度。
换言之，本申请实施例中，定位系统至少包括：
第一电子设备，用于采集并输出第二车辆速度；
第二电子设备，用于接收并输出卫星定位数据；
第三电子设备，用于采集并输出车辆的角速度；
第四电子设备，用于执行前述任一实现方式所述的方法。
具体而言，本申请的一个实施例中，第二电子设备为卫星信号接收装置。例如，可以为GPS模块，此时，GPS定位位置可以通过对GPS模块输出的GPS报文进行解析得到。其中，GPS模块可以是搭载于车辆中的车载GPS，或者，还可以是与车辆相连接的可移动设备中搭载的GPS。
GPS模块能够接收卫星发送的GPS报文，并输出GPS报文或GPS数据。若通过可移动设备中的GPS来采集车辆的GPS定位数据，则GPS模块可以将可移动设备输出至可移动设备的通信模块，并由可移动设备的通信模块将GPS报文以前述近距离通信方式，发送给车辆处理器。或者，若通过与车辆处理器相连接的车载GPS来采集GPS数据，则车载GPS可以通过连接线(例如，运营商VLAN(Provider VLAN Transport，PVT)总线)将GPS报文直接输出给车辆处理器。或者，若车辆中设计控制器局域网络(Controller Area Network，CAN)收发模块，CAN收发模块用于实现车辆处理器与各数据采集装置之间的数据交互。此时，车载GPS可以将GPS报文输出给CAN收发模块，而车辆处理器可以通 过CAN总线获取到GPS报文。
在前述各设计中，车辆处理器接收GPS模块输出的GPS报文，在具体实现DR推算和车辆速度的修正处理之前，还需要对GPS报文进行解析，以提取出其中的GPS数据。但是，在其他可能的设计中，GPS模块还可用于在接收到GPS报文后对其进行解析，此时，GPS模块输出GPS数据，不作赘述。或者，在另外的设计中，在GPS模块与车辆处理器之间的任意相邻的两个数据交互节点之间，还可以额外设置数据解析模块，数据解析模块用于对接收到的GPS报文进行解析，并输出解析后的GPS数据。
一种可能的实现方式中，车载GPS与车辆控制器通过RS232接口连接，车载GPS通过RS232接口输出NMEA格式的GPS报文。其输出频率可以为1HZ或更高,输出数据速率为115200bps以上。
本申请的另一个实施例中，第三电子设备为角速度采集装置。需要说明的是，角速度采集装置可以是硬件设备，如陀螺仪(gyroscope，GYRO)；或者，也可以通过软件算法来计算出车辆角速度，此时，角速度采集装置可以为处理器或处理模块。与GPS模块类似的，角速度采集装置可以搭载于车辆中，也可以搭载于可移动设备中。
以角速度采集装置为陀螺仪为例。若陀螺仪搭载于可移动设备中，那么，通过可移动设备的通信模块与车辆处理器之间的近距离通信连接，来传输角速度数据。若陀螺仪与车辆控制器之间可以通过SPI总线连接并交互数据。若陀螺仪与CAN收发模块相连接，则车辆处理器可以通过CAN总线获取到车辆的角速度数据。
此外，陀螺仪可以实时采集并记录车辆的角速度，并通过串行外设接口(Serial Peripheral Interface，SPI)总线传输给车辆控制器。或者，陀螺仪可以按照预设的采样频率，将定时采集到的角速度数据通过SPI总线传输给车辆控制器。其中，陀螺仪的采样频率需要适应DR推算一个位置的时间间隔。例如，一种可能的实现方式中，DR推算一个位置需要0.025秒，则陀螺仪的采样频率可以为40HZ。
本申请的另一个实施例中，第一电子设备可以为轮速采集装置，可以为CAN总线，或者，还可以为车辆中搭载的车速表。其中，轮速采集装置一般搭载于车辆中。具体而言，轮速采集装置可以为搭载于车辆中的独立设备，或者，可以集成在车辆的某一个或多个处理器中。轮速采集装置可以通过CAN总线与车辆控制器进行通信和数据交互，车辆控制器通过CAN总线获取到车辆速度。而车辆速度的获取频率(或称为采样频率)则需要根据车辆的实际输出频率来进行设计，本申请对此无特别限定。
本申请所提供的DR推算及其车辆速度修正方案，可以在车辆中实施。也就是，所述第一电子设备、所述第二电子设备、所述第三电子设备、所述第四电子设备与所述第五电子设备，都搭载于所述车辆中。
此时，一种可能的实现中，所述第一电子设备为速度采集装置、所述车辆总线或者车辆的速度表；所述第二电子设备为卫星信号接收装置；所述第三电子设备为陀螺仪；所述第四电子设备与所述第五电子设备为车辆处理器。
图14示出了一种车辆的架构示意图。如图14所示，该车辆包括：车辆主体，以及，车辆处理器110、陀螺仪120、CAN收发器130与车载GPS140。其中，车载GPS140、陀螺仪130、CAN收发器130分别与车辆处理器110连接，并分别向车辆处理器110提供GPS数据、角速度数据与车辆速度数据，构成一个定位系统。而车辆处理器110在接收到 各数据后，进行DR推算，并在达到修正条件时对车辆速度进行修正。这种实现方式完全在车辆内部实现，避免了与外部可移动设备的通信时延对DR推算结果的不利影响。
需要说明的是，车辆处理器110可以为车辆总控制器中的一个或多个处理单元或处理模块，其可以为单独的处理器，也可以集成于现有的处理设备中。
本申请实施例中，车辆处理器110，具体用于根据采集或接收得到的GPS数据、车辆速度数据与角速度数据，进行DR推算，并在达到修正条件时，修正车辆速度；以及，车辆处理器110还用于在GPS信号较差的情况下，输出DR推算结果。其中，DR推算结果可以最终输出至车辆或可移动设备中的显示屏幕上，例如，输出至图1B所示的导航显示屏上，以方便用户了解当前车辆的行驶位置。和/或，DR推算结果还可以通过PVT总线输出至导航引擎，以便于导航引擎根据DR推算结果来为车辆进行路段导航。
本申请所涉及到的处理器可以包括一个或多个处理单元，例如：处理器可以包括应用处理器(application processor，AP)，调制解调处理器，图形处理器(graphics processing unit，GPU)，图像信号处理器(image signal processor，ISP)，视频处理单元(video processing unit，VPU)控制器，存储器，视频编解码器，数字信号处理器(digital signal processor，DSP)，基带处理器，和/或神经网络处理器(neural-network processing unit，NPU)等。其中，不同的处理单元可以是独立的器件，也可以集成在一个或多个处理器中。
其中，控制器可以是头戴电子设备的神经中枢和指挥中心。控制器可以根据指令操作码和时序信号，产生操作控制信号，完成取指令和执行指令的控制。
处理器中还可以设置存储器，用于存储指令和数据。在一些实施例中，处理器中的存储器为高速缓冲存储器。该存储器可以保存处理器刚用过或循环使用的指令或数据。如果处理器需要再次使用该指令或数据，可从所述存储器中直接调用。避免了重复存取，减少了处理器的等待时间，因而提高了系统的效率。
除此之外，本申请所提供的DR推算及其车辆速度修正方案，也可以在与车辆相连接的可移动设备中实施。也就是，由可移动设备的处理器进行DR推算、速度修正处理、路线导航处理等。当通过可移动设备来实施本方案时，前述各数据的最终接收方为可移动设备的处理器。
或者，前述方法，还可以在车辆与可移动设备之间交叉实施。此时，定位系统可以分布在多个设备上。具体的，所述第一电子设备、所述第二电子设备、所述第三电子设备、所述第四电子设备与所述第五电子设备中，部分电子设备搭载于所述车辆，部分电子设备搭载于可移动设备；其中，搭载于所述车辆中的部分电子设备与搭载于所述可移动设备中的部分电子设备，通信连接。例如，由车辆处理器进行DR推算，并修正车辆速度，由可移动设备根据DR推算结果进行路线导航。又例如，由可移动设备进行DR推算，但是由车辆修正车辆速度。
需要说明的是，若通过可移动设备来实施本方案，需要车辆与可移动设备建立近距离通信连接。所谓近距离通信连接，是指可移动设备与车辆之间可以通过近距离通信手段进行通信，从而，通过该通信关系的通断，判断车辆与可移动设备之间是否处于同一地理位置。可以理解，若车辆与可移动设备能够正常的近距离通信，则可以采用可移动设备中GPS采集到的定位位置作为车辆的定位位置；否则，若车辆与可移动设备在预设第二时长范围内都无法正常通信(例如，接收不到传输的数据)，则可移动设备中GPS采集到的定位位 置不可作为车辆的定位位置。
本申请实施例所涉及到的近距离通信连接方式可以包括但不限于：无线局域网(wireless local area networks，WLAN)(如无线保真(wireless fidelity，Wi-Fi)网络)，蓝牙(Bluetooth，BT)，调频(frequency modulation，FM)，近距离无线通信技术(near field communication，NFC)，红外技术(infrared，IR)等无线通信的解决方案，以及有线通信的解决方案。
本申请所涉及到的可移动设备可以包括但不限于：终端、可穿戴设备中的至少一种。
其中，终端可以是有线终端也可以是无线终端。无线终端是可以是指向用户提供语音和/或其他业务数据连通性的设备，具有无线连接功能的手持式设备、或连接到无线调制解调器的其他处理设备。无线终端可以经无线接入网(Radio Access Network，RAN)与一个或多个核心网设备进行通信，无线终端可以是移动终端，如移动电话(或称为“蜂窝”电话)和具有移动终端的计算机，例如，可以是便携式、袖珍式、手持式、计算机内置的或者车载的移动装置，它们与无线接入网交换语言和/或数据。再例如，无线终端还可以是个人通信业务(Personal Communication Service，PCS)电话、无绳电话、会话发起协议(Session Initiation Protocol，SIP)话机、无线本地环路(Wireless Local Loop，WLL)站、个人数字助理(Personal Digital Assistant，PDA)等设备。无线终端也可以称为系统、订户单元(Subscriber Unit)、订户站(Subscriber Station)、移动站(Mobile Station)、移动台(Mobile)、接入终端(Access terminal)、用户终端(User Terminal)、用户代理(User Agent)、用户设备(User Device or User Equipment)，在此不作限定。
可穿戴设备可以是头戴式设备也可以是其他便携式设备。头戴式设备可以是眼镜、头戴电子设备、护目镜等。其他便携设备可以是智能手环、智能手表、可穿戴耳机等设备。
为了便于理解，可以参考如图15～图19的几种具体实现方式。
图15示出了一种包含车辆与可移动设备的定位系统的架构示意图。如图15所示，车辆中设置有车辆处理器110、陀螺仪120、CAN收发器130与车载GPS140，车辆处理器110与可移动设备通信连接。
在如图15所示的实现场景中，车辆处理器110可以自陀螺仪120、CAN收发器130与车载GPS140中，获取到角速度、车辆速度与GPS数据，在此基础上，车辆处理器110并不用于直接实施DR推算与速度修正处理，车辆处理器110将角速度、车辆速度与GPS数据分别发送给可移动设备，由可移动设备执行DR推算与速度修正处理。这种实现方式能够适用于用户通过手机、平板电脑等便携式终端实现车辆定位的需求。以及，可移动设备实现DR推算的数据来源于车辆，这也能够在一定程度上简化可移动设备的硬件结构与软件逻辑，能够满足可移动设备的便携需求。
除图15所示的方式之外，还可以在可移动设备中设计部分数据采集模块，以降低车辆与可移动数据之间的数据交互负担。图16示出了一种包含车辆与可移动设备的定位系统的架构示意图。如图16所示，车辆中设置有车辆处理器110、陀螺仪120与CAN收发器130，而可移动设备中设置有处理器210与GPS模块220，并且，车辆处理器110与处理器210近距离通信连接。
在如图16的一种可能的实现方式中，可以由车辆处理器110来执行DR推算和速度修正处理。此时，处理器210接收到GPS模块220输出的GPS报文或数据后，通过近距离 通信连接方式，转发给车辆处理器110。其中，若GPS模块220输出GPS报文，还可以在处理器210处对GPS报文进行解析，处理器210将解析后的GPS数据发送给车辆处理器110。车辆处理器110还可以获取陀螺仪120采集的到的角速度数据，从CAN收发器130获取车辆速度数据，进而，执行DR推算和速度修正处理。
在如图16的另一种可能的实现方式中，可以由处理器210来执行DR推算和速度修正处理。此时，处理器210接收GPS模块220输出的GPS报文或GPS数据。而车辆处理器110则获取陀螺仪120采集的到的角速度数据，并从CAN收发器130获取车辆速度数据，将角速度数据与车辆速度数据分别发送给可移动设备中的处理器210，由处理器210执行DR推算和速度修正处理。
前述实现方式中，只涉及对DR推算过程所使用的车辆速度进行补偿修正，除此之外，还可以对车辆中显示和/或记录的车辆速度进行修正。可以理解，也可以对可移动设备中显示和/或记录的车辆速度进行修正。
在图16所示的系统架构下，图17示出了这种实现方式的一种数据交互过程：可移动设备中的处理器210获取(或接受)GPS数据、角速度与车辆速度，并基于此进行DR推算，在DR推算过程中，获取DR定位的速度补偿因子，并利用速度补偿因子来修正DR推算过程所使用的车辆速度。并且，处理器210还将获取到速度补偿因子发送给车辆处理器110，由车辆处理器110来对车辆中记录和/或显示的车辆速度进行修正，例如，对车辆中搭载的仪表盘中车速表所显示的车辆速度进行更新。此外，在具体的实现场景中，如图17所示，还可以由可移动设备根据DR推算结果进行路线导航。
此外，角速度也可以通过设置于可移动设备中的陀螺仪230获取得到。此时，图18示出了另一种包含车辆与可移动设备的定位系统的架构示意图。如图18所示，车辆中设置有车辆处理器110与CAN收发器130，而可移动设备中设置有处理器210、陀螺仪230与GPS模块220，并且，车辆处理器110与处理器210近距离通信连接。车辆处理器110通过CAN收发器130获取到车辆速度后，通过近距离通信连接发送给可移动设备中的处理器210，处理器210从陀螺仪230获取角速度，从GPS模块220获取GPS数据，并进行DR推算以及车辆速度的修正处理。
本申请实施例中，对于车辆连接的可移动设备的数目无特别限定。具体而言，可移动设备的数目可以至少一个，例如，可以如图15～图18所示的场景，该定位系统中只有一个可移动设备；或者，可移动设备的数目也可以有多个。
图19示出了一种可能的情况。如图19所示，该定位系统中包括：车辆、第一可移动设备、第二可移动设备。其中，第一可移动设备包括陀螺仪230与处理器210，其中，处理器210与车辆处理器110近距离通信连接，第二可移动设备包括处理器310与GPS模块320，其中，处理器310与车辆处理器110近距离通信连接。
在如图19所示的实现场景中，DR推算方法及其车辆速度的修正处理，可以在车辆处理器110中实现，车辆处理器110通过处理器210获取陀螺仪230采集到的角速度，通过处理器310获取GPS模块320记录的GPS数据。
以及，在如图19所示的实现场景中，DR推算方法及其车辆速度的修正处理，可以在至少一个可移动设备中实现。此时，车辆处理器110作为第一可移动设备与第二可移动设备之间数据交互的桥梁，用于转发车辆速度与接收到的其他数据。或者，若第一可移动设 备与第二可移动设备还通过其他有线或无线方式连接时，则可以在车辆、第一可移动设备、第二可移动设备之间设计任意的数据交互方式。
此外，本申请实施例还提供了一种计算机可读存储介质，所述计算机可读存储介质中存储有指令，当所述指令在电子设备上运行时，使得所述电子设备执行前述任一实施例所述的方法。
本申请实施例还提供了一种计算机程序产品，当计算机程序产品在电子设备上运行时，使得电子设备执行如前述任一实施例所述的方法。
本申请的各实施方式可以任意进行组合，以实现不同的技术效果。
在上述实施例中，可以全部或部分地通过软件、硬件、固件或者其任意组合来实现。当使用软件实现时，可以全部或部分地以计算机程序产品的形式实现。所述计算机程序产品包括一个或多个计算机指令。在计算机上加载和执行所述计算机程序指令时，全部或部分地产生按照本申请所述的流程或功能。所述计算机可以是通用计算机、专用计算机、计算机网络、或者其他可编程装置。所述计算机指令可以存储在计算机可读存储介质中，或者从一个计算机可读存储介质向另一个计算机可读存储介质传输，例如，所述计算机指令可以从一个网站站点、计算机、服务器或数据中心通过有线(例如同轴电缆、光纤、数字用户线)或无线(例如红外、无线、微波等)方式向另一个网站站点、计算机、服务器或数据中心进行传输。所述计算机可读存储介质可以是计算机能够存取的任何可用介质或者是包含一个或多个可用介质集成的服务器、数据中心等数据存储设备。所述可用介质可以是磁性介质，(例如，软盘、硬盘、磁带)、光介质(例如，DVD)、或者半导体介质(例如固态硬盘Solid State Disk)等。
总之，以上所述仅为本申请技术方案的实施例而已，并非用于限定本申请的保护范围。凡根据本申请的揭露，所作的任何修改、等同替换、改进等，均应包含在本申请的保护范围之内。
显然，本领域的技术人员可以对本申请进行各种改动和变型而不脱离本申请的精神和范围。这样，倘若本申请的这些修改和变型属于本申请权利要求及其等同技术的范围之内，则本申请也意图包含这些改动和变型在内。

Claims (26)

  1. 一种定位方法，其特征在于，包括：
    当车辆在第一环境中行驶时，显示卫星定位系统定位的第一车辆位置，所述第一环境的卫星信号质量满足预设质量要求；
    当所述车辆在第二环境中行驶时，显示第二车辆位置，所述第二环境的卫星信号质量不满足所述预设质量要求；
    其中，所述第二车辆位置是利用第一车辆速度推算得到的，所述第一车辆速度是利用卫星定位位置与航位推算位置对第二车辆速度修正得到的，所述第二车辆速度为所述车辆在行驶过程中获取到的速度。
  2. 根据权利要求1所述的方法，其特征在于，所述第一车辆速度，是利用速度补偿因子修正所述第二车辆速度得到的，所述速度补偿因子是根据所述卫星定位位置与所述航位推算位置获取到的。
  3. 根据权利要求2所述的方法，其特征在于，所述速度补偿因子，是在满足预设的修正条件时，根据所述卫星定位位置与所述航位推算位置获取到的。
  4. 根据权利要求3所述的方法，其特征在于，所述修正条件至少包括：所述卫星信号质量满足所述预设质量要求。
  5. 根据权利要求1-4任一项所述的方法，其特征在于，所述预设质量要求包括：
    卫星处于有效定位状态；
    卫星的水平精度因子小于或者等于预设的精度阈值；
    处于有效定位状态的卫星数目大于或者等于预设的第一数目阈值；
    信号强度大于或者等于预设的强度阈值的卫星，其总数大于或者等于预设的第二数目阈值。
  6. 根据权利要求5所述的方法，其特征在于，所述卫星信号质量满足所述预设质量要求，包括：
    所述卫星信号在预设的连续时长范围内，均满足所述预设质量要求；或者，
    所述卫星信号瞬时即满足所述预设质量要求。
  7. 根据权利要求3或4所述的方法，其特征在于，所述修正条件还包括如下至少一种：
    从所述航位推算的起始点开始，所述车辆的行驶里程达到预设的距离阈值；
    所述航位推算位置与所述卫星定位位置之间的里程差大于预设的误差阈值；
    从所述航位推算的所述起始点开始，所述车辆满足预设的直行条件。
  8. 根据权利要求7所述的方法，其特征在于，所述直行条件包括：
    从所述起始点开始，所述车辆的航向角的变化量小于或等于预设角度；或者，
    所述车辆从所述起始点开始在直行道路上单向行驶。
  9. 根据权利要求2或3所述的方法，其特征在于，所述方法还包括：
    获取所述卫星定位位置与所述航位推算位置之间的里程差；其中，所述卫星定位位置与所述航位推算位置相对应；
    获取所述里程差与耗时时长之间的比值，得到所述速度补偿因子；其中，所述耗时时长为所述航位推算的起始点至所述航位推算位置之间花费的时长。
  10. 根据权利要求2或3所述的方法，其特征在于，所述方法还包括：
    获取所述速度补偿因子与所述第二车辆速度之和，得到所述第一车辆速度；
    其中，在所述车辆的行驶方向上，若所述航位推算位置落在所述卫星定位位置的前方，所述速度补偿因子为负值；或者，在所述车辆的行驶方向上，若所述航位推算位置落在所述卫星定位位置的后方，所述速度补偿因子为正值。
  11. 根据权利要求1-10任一项所述的方法，其特征在于，所述航位推算位置是从起始点开始依次推算得到的；
    所述起始点，是在满足预设的起始条件时，获取到的所述卫星定位位置。
  12. 根据权利要求11所述的方法，其特征在于，所述起始点，是在满足预设的起始更新条件，且满足所述预设的起始条件时，获取到的所述卫星定位位置。
  13. 根据权利要求11或12所述的方法，其特征在于，所述起始条件包括：
    满足所述车辆速度达到预设的起始速度阈值，与所述车辆的行驶里程达到预设的起始里程阈值中的至少一个；
    所述卫星信号质量满足所述预设质量要求；
    所述车辆的航行稳定。
  14. 根据权利要求12所述的方法，其特征在于，所述起始更新条件，包括如下至少一种：
    所述航位推算的推算次数达到预设的次数阈值；
    从所述起始点开始，所述车辆的行驶里程达到预设的距离阈值；
    所述卫星定位位置与所述航位推算位置之间的里程差大于预设的误差阈值；
    所述车辆的航向角的变化量大于预设角度；
    满足预设的修正条件。
  15. 根据权利要求8或14所述的方法，其特征在于，所述航向角是由车辆的角速度处理得到的。
  16. 根据权利要求1-15任一项所述的方法，其特征在于，所述第二车辆速度由第一电子设备采集得到，所述卫星定位位置由第二电子设备采集得到，所述车辆的角速度由第三电子设备采集得到，所述第一车辆速度在第四电子设备中修正得到，所述航位推算位置在第五电子设备中推算得到；
    所述第一电子设备、所述第二电子设备、所述第三电子设备、所述第四电子设备与所述第五电子设备中，任意两种电子设备为同一电子设备，或者不同电子设备。
  17. 根据权利要求16所述的方法，其特征在于，所述第一电子设备、所述第二电子设备、所述第三电子设备、所述第四电子设备与所述第五电子设备，都搭载于所述车辆中。
  18. 根据权利要求16所述的方法，其特征在于，所述第一电子设备、所述第二电子设备、所述第三电子设备、所述第四电子设备与所述第五电子设备中，部分电子设备搭载于所述车辆，部分电子设备搭载于可移动设备；
    其中，搭载于所述车辆中的部分电子设备与搭载于所述可移动设备中的部分电子设备，通信连接。
  19. 根据权利要求18所述的方法，其特征在于，所述可移动设备的数目为至少一个。
  20. 根据权利要求16或17所述的方法，其特征在于，所述第一电子设备为速度采集装 置、所述车辆总线或者车辆的速度表；所述第二电子设备为卫星信号接收装置；所述第三电子设备为陀螺仪；所述第四电子设备与所述第五电子设备为车辆处理器。
  21. 根据权利要求1-20任一项所述的方法，其特征在于，所述卫星信号包括：全球定位系统GPS卫星信号、北斗卫星导航系统卫星信号、格洛纳斯卫星导航系统GLONASS卫星信号或者伽利略卫星导航系统卫星信号。
  22. 一种电子设备，其特征在于，包括：
    一个或多个处理器；
    一个或多个存储器；
    一个或多个传感器；
    以及一个或多个计算机程序，其中所述一个或多个计算机程序被存储在所述一个或多个存储器中，所述一个或多个计算机程序包括指令，当所述指令被所述电子设备执行时，使得所述电子设备执行如权利要求1-21中任一项所述的方法。
  23. 一种定位系统，其特征在于，包括：
    第一电子设备，用于采集并输出第二车辆速度；
    第二电子设备，用于接收并输出卫星定位数据；
    第三电子设备，用于采集并输出车辆的角速度；
    第四电子设备，用于执行如权利要求1-21任一项所述的方法。
  24. 一种计算机可读存储介质，所述计算机可读存储介质中存储有指令，其特征在于，当所述指令在电子设备上运行时，使得所述电子设备执行如权利要求1-21中任一项所述的方法。
  25. 一种车辆，其特征在于，包括：
    车辆主体；
    如权利要求22所述的电子设备；或者，如权利要求23所述的定位系统。
  26. 一种程序产品，其特征在于，所述程序产品包括计算机程序，所述计算机程序存储在可读存储介质中，通信装置的至少一个处理器可以从所述可读存储介质读取所述计算机程序，所述至少一个处理器执行所述计算机程序使得通信装置实施如权利要求1-21任意一项所述的方法。
PCT/CN2020/111222 2019-08-30 2020-08-26 定位方法与系统、电子设备、车辆与存储介质 WO2021037038A1 (zh)

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