A parking system trajectory tracking and positioning method and system

Abstract

The present invention discloses a parking system trajectory tracking and positioning method and system, including: establishing a space coordinate system of a vehicle model, determining the position coordinates of each radio wave receiver set on the vehicle, determining the relative position of a key and each radio wave receiver, and obtaining the relationship between the key and the vehicle model; locating the key according to the relative position of the key and each radio wave receiver to obtain the position coordinates of the key; determining the movement trend of the key according to the change trend of the light offset of the radio wave; determining the displacement vector of each radio wave receiver according to the movement trend of the key; performing vector synthesis on the displacement vectors of each radio wave receiver in a unit time to obtain the vehicle displacement vector in a unit time; integrating the vehicle displacement vectors in continuous unit time to obtain the vehicle movement trajectory. The present invention completes the calculation of the vehicle trajectory during the parking process and is used for subsequent trajectory calibration without adding an additional controller and cost.

Description

Technical Field

[0001] The present invention belongs to the technical field of vehicle radio frequency radiation detection, and in particular relates to a parking system trajectory tracking and positioning method and system. Background Art

[0002] The existing technology has the following defects: (1) Positioning accuracy requires strong GPS signal support and cannot adapt to environments such as garages; if higher accuracy is required, differential processing is also required, which also requires field equipment and large computing power support in the car. (2) High-precision maps are required, but high-precision maps require very high licensing costs and require the support of high-computing chips, which will increase the corresponding hardware, development, and licensing costs. Summary of the invention

[0003] The object of the present invention is to provide a parking system trajectory tracking and positioning method and system, which can complete the calculation of the vehicle trajectory during the parking process and use it for subsequent trajectory calibration without adding additional controllers and costs.

[0004] In order to solve the above technical problems, the technical solution of the present invention is: a parking system trajectory tracking and positioning method, comprising the following steps:

[0005] According to the arrangement and installation of the vehicle, a space coordinate system of the vehicle model is established, the position coordinates of each radio wave receiver arranged on the vehicle are determined, the relative positions of the key and each radio wave receiver are determined through the radio wave transmission between the key and each radio wave receiver, and the relationship between the key and the vehicle model is obtained; the number of radio wave receivers to be arranged is at least 3;

[0006] After the vehicle is started, the key transmits a starting radio wave, and the key is located according to the relative position of the key and each radio wave receiver to obtain the position coordinates of the key;

[0007] During vehicle operation, the key continuously sends radio waves to each radio wave receiver, and the movement trend of the key is determined based on the trend of the light offset of the radio waves;

[0008] Determine the displacement vector of each radio wave receiver according to the movement trend of the key;

[0009] Perform vector synthesis on the displacement vectors of each radio wave receiver in unit time to obtain the movement direction of the vehicle in unit time and the displacement vector of the vehicle in unit time;

[0010] The vehicle displacement vector in continuous unit time is integrated to obtain the vehicle's motion trajectory.

[0011] The optical deviation of radio waves is calculated as:

[0012]

[0013] Where Δθ is the theoretical value of the optical offset of the signal, v e is the end frequency of the laser sweep, v s is the standard frequency of laser sweep, Δv=v e -v s is the laser frequency sweep range, l is the optical path difference, and c is the speed of light in vacuum.

[0014] The calculation of the optical offset of the radio wave also includes the following steps: eliminating the actual deviation of the optical offset to obtain the actual value of the optical offset, and the calculation method is:

[0015]

[0016] In the formula, Δθ m is the actual value of light offset, l e is the distance between the key and a radio wave receiver at the time of radio wave reception; l s The distance between a key that emits radio waves and a radio wave receiver;

[0017] Let Δl = l e -l s , then:

[0018]

[0019] Δθ m Substituting into (1), we get:

[0020]

[0021] Right now

[0022]

[0023] In the formula, l m is the calculated distance between the key and a radio wave receiver when the radio wave is emitted after the vehicle moves, Δl is the offset of the wave path difference, Δk is the change in laser wave number corresponding to the laser sweep range, k e is the wave number corresponding to the end frequency of the sweep, Δθ err =k e is the error phase offset caused by target motion.

[0024] The key position coordinates are calculated as follows:

[0025] P(d)=P T -A (7)

[0026]

[0027] Where P T is the transmission power of the signal, and the signal strength received at the reference point at a distance of d0 from the transmitting node is A=P T -P0, n is the path loss factor; P RSSI is the received signal strength indication, P0 is the simulated received power at the location of the transmitting node, and P(d) is the received power at the location d away from the transmitting node.

[0028] The distance from the key to a single radio wave receiver is measured by equations (7) and (8). The path loss factor n varies with the movement of the positioning node and is obtained by the real vehicle calibration method:

[0029]

[0030] Where, (x1, y1)(x2, y2)(x3, y3) are the position coordinates of each radio wave receiver respectively;

[0031] As the positioning node moves, the corresponding path loss factor n is calibrated according to the distance d to obtain the location coordinates (x, y) of the key.

[0032] A parking system trajectory tracking and positioning system is also provided, comprising a controller and a key. The controller calls a parking system trajectory tracking and positioning method as described above when calculating a parking trajectory.

[0033] The optical deviation of radio waves is calculated as:

[0034]

[0035] Where Δθ is the theoretical value of the optical offset of the signal, v e is the end frequency of the laser sweep, v s is the standard frequency of laser sweep, Δv=v e -v s is the laser frequency sweep range, l is the optical path difference, and c is the speed of light in vacuum.

[0036] The calculation of the optical offset of the radio wave also includes the following steps: eliminating the actual deviation of the optical offset to obtain the actual value of the optical offset, and the calculation method is:

[0037]

[0038] In the formula, Δθ m is the actual value of light offset, l e is the distance between the key and a radio wave receiver at the time of radio wave reception; l s The distance between a key that emits radio waves and a radio wave receiver;

[0039] Let Δl = l e -l s , then:

[0040]

[0041] Δθ m Substituting into (1), we get:

[0042]

[0043] Right now

[0044]

[0045] In the formula, l m is the calculated distance between the key and a radio wave receiver when the radio wave is emitted after the vehicle moves, Δl is the offset of the wave path difference, Δk is the change in laser wave number corresponding to the laser sweep range, k e is the wave number corresponding to the end frequency of the sweep, Δθ err =k e is the error phase offset caused by target motion.

[0046] The key position coordinates are calculated as follows:

[0047] P(d)=P T -A (7)

[0048]

[0049] Where P T is the transmission power of the signal, and the signal strength received at the reference point at a distance of d0 from the transmitting node is A=P T -P0, n is the path loss factor; P RSSI It is the abbreviation of Received Signal Strength Indicator, which is a measure of wireless signal strength. It is usually used to remind users of the current signal strength to prevent loss of control. P0 is the simulated received power at the location of the transmitting node. P(d) is the received power at the location d away from the transmitting node.

[0050] The distance from the key to a single radio wave receiver is measured by equations (7) and (8). The path loss factor n varies with the movement of the positioning node and is obtained by the real vehicle calibration method:

[0051]

[0052] Where, (x1, y1)(x2, y2)(x3, y3) are the position coordinates of each radio wave receiver respectively;

[0053] As the positioning node moves, the corresponding path loss factor n is calibrated according to the distance d to obtain the location coordinates (x, y) of the key.

[0054] A computer device is also provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of any of the above methods when executing the computer program.

[0055] A computer-readable storage medium is also provided, on which a computer program is stored, and when the computer program is executed by a processor, the steps of any of the above methods are implemented.

[0056] Compared with the prior art, the present invention has the following beneficial effects:

[0057] The present invention completes the calculation of the vehicle trajectory during the parking process and uses it for subsequent trajectory calibration without adding an additional controller and cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 A schematic diagram of a flow chart of an embodiment of the present invention;

[0059] Figure 2 It is a schematic diagram of signal transmission between a key and a radio wave receiver when a vehicle moves at a constant speed in an embodiment of the present invention;

[0060] Figure 3 Schematic diagram of signal transmission between a key and a radio wave receiver when a vehicle accelerates in an embodiment of the present invention. DETAILED DESCRIPTION

[0061] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0062] The technical solution of the present invention is:

[0063] Embodiment 1:

[0064] A parking system trajectory tracking and positioning method, such as Figure 1 As shown, the following steps are included:

[0065] S1: Establishment of vehicle and key motion model

[0066] According to the arrangement and installation of the vehicle, a space coordinate system of the vehicle model is established, the position coordinates of each radio wave receiver arranged on the vehicle are determined, the relative positions of the key and each radio wave receiver are determined through the radio wave transmission between the key and each radio wave receiver, and the relationship between the key and the vehicle model is obtained; the number of radio wave receivers to be arranged is at least 3;

[0067] The general arrangement of receiving antennas is: one main antenna is arranged in the car, and two auxiliary antennas are arranged on the door handles.

[0068] S2: Key location in the car

[0069] The signal emitted by the keyless entry and start module in the vehicle (the present invention is applicable to both key start and keyless start models) is directly used for distance measurement, and then the three-point positioning method is used to determine the position of the key in the vehicle.

[0070] After the vehicle is started, the key transmits a starting radio wave, and the key is located according to the relative position of the key and each radio wave receiver to obtain the position coordinates of the key;

[0071] S3: Calculation of light offset

[0072] Traditional keyless entry positioning solutions can only realize the positioning of the key in the car. The embodiments of the present invention utilize the characteristics of radio wave low beam and the change of offset to further identify the movement trend of the key and each radio wave receiver, thereby providing raw data support for subsequent positioning.

[0073] When a radio wave receiver receives radio waves, the frequency of the radio waves will be slightly different from the standard frequency. At this time, the theoretical value of the phase offset measured is Δθ.

[0074] During vehicle operation, the key continuously sends radio waves to each radio wave receiver, and the movement trend of the key is determined based on the trend of the light offset of the radio waves;

[0075] S4: Confirmation of vehicle displacement

[0076] The distance change corresponding to a single radio wave receiver and the key is calculated as follows: for the moment of the signal cycle t, the inertia of the vehicle's movement, the key distance d (following relative to stillness) calculated by the key power, and the displacement l calculated by the wave path difference s The displacement vector a of a single radio wave receiver is obtained, where the modulus of a is |l s -d|.

[0077] Determine the displacement vector of each radio wave receiver according to the movement trend of the key;

[0078] S5: Vector synthesis of vehicle displacement per unit time

[0079] For each radio wave receiver per unit time Perform vector synthesis to obtain the vehicle's movement direction per unit time. Obtain the vehicle's displacement vector per unit time.

[0080] Perform vector synthesis on the displacement vectors of each radio wave receiver in unit time to obtain the movement direction of the vehicle in unit time and the displacement vector of the vehicle in unit time;

[0081] S6: Integrate the vehicle displacement per unit time

[0082] For the vehicle displacement vector in continuous unit time Perform integration processing to obtain the vehicle's motion trajectory.

[0083] The optical deviation of radio waves is calculated as:

[0084]

[0085] Where Δθ is the theoretical value of the optical offset of the signal, v e is the end frequency of the laser sweep, v s is the standard frequency of laser sweep, Δv=v e -v s is the laser frequency sweep range, l is the optical path difference, and c is the speed of light in vacuum.

[0086] The calculation of the optical offset of the radio wave also includes the following steps: eliminating the actual deviation of the optical offset to obtain the actual value of the optical offset, and the calculation method is:

[0087]

[0088] In the formula, l m is the calculated distance between the key and a radio wave receiver when the radio wave is emitted after the vehicle moves, Δθ m is the actual value of light offset, l e is the distance between the key and a radio wave receiver at the time of radio wave reception; l s The distance between a key that emits radio waves and a radio wave receiver;

[0089] Let Δl = l e -l s , then:

[0090]

[0091] Δθ m Substituting into (1), we get:

[0092]

[0093] Right now

[0094]

[0095] Where Δl is the offset of the wave path difference, Δk is the change of the laser wave number corresponding to the laser sweep range, and k e is the wave number corresponding to the end frequency of the sweep, Δθ err =k e is the error phase offset caused by target motion.

[0096] The key position coordinates are calculated as follows:

[0097] P(d)=P T -A (7)

[0098]

[0099] Where P T is the transmission power of the signal, and the signal strength received at the reference point at a distance of d0 from the transmitting node is A=P T -P0, n is the path loss factor; P RSSI is the received signal strength indication, P0 is the simulated received power at the location of the transmitting node, and P(d) is the received power at the location d away from the transmitting node.

[0100] The distance from the key to a single radio wave receiver is measured by equations (7) and (8). The path loss factor n varies with the movement of the positioning node and is obtained by the real vehicle calibration method:

[0101]

[0102] Where, (x1, y1)(x2, y2)(x3, y3) are the position coordinates of each radio wave receiver respectively;

[0103] As the positioning node moves, the corresponding path loss factor n is calibrated according to the distance d to obtain the location coordinates (x, y) of the key.

[0104] Embodiment 2:

[0105] A parking system trajectory tracking and positioning system is also provided, comprising a controller and a key. The controller calls a parking system trajectory tracking and positioning method as described above when calculating a parking trajectory.

[0106] The optical deviation of radio waves is calculated as:

[0107]

[0108] Where Δθ is the theoretical value of the optical offset of the signal, v e is the end frequency of the laser sweep, v s is the standard frequency of laser sweep, Δv=v e -v s is the laser frequency sweep range, l is the optical path difference, and c is the speed of light in vacuum.

[0109] The calculation of the optical offset of the radio wave also includes the following steps: eliminating the actual deviation of the optical offset to obtain the actual value of the optical offset, and the calculation method is:

[0110]

[0111] In the formula, Δθ m is the actual value of light offset, l e is the distance between the key and a radio wave receiver at the time of radio wave reception; l s The distance between a key that emits radio waves and a radio wave receiver;

[0112] Let Δl = l e -l s , then:

[0113]

[0114] Δθ m Substituting into (1), we get:

[0115]

[0116] Right now

[0117]

[0118] In the formula, l m is the calculated distance between the key and a radio wave receiver when the radio wave is emitted after the vehicle moves, Δl is the offset of the wave path difference, Δk is the change in laser wave number corresponding to the laser sweep range, k e is the wave number corresponding to the end frequency of the sweep, Δθ err =k e is the error phase offset caused by target motion.

[0119] The key position coordinates are calculated as follows:

[0120] P(d)=P T -A (7)

[0121]

[0122] Where P Tis the transmission power of the signal, and the signal strength received at the reference point at a distance of d0 from the transmitting node is A=P T -P0, n is the path loss factor; P RSSI is the received signal strength indication, P0 is the simulated received power at the location of the transmitting node, and P(d) is the received power at the location d away from the transmitting node.

[0123] The distance from the key to a single radio wave receiver is measured by equations (7) and (8). The path loss factor n varies with the movement of the positioning node and is obtained by the real vehicle calibration method:

[0124]

[0125] Where, (x1, y1)(x2, y2)(x3, y3) are the position coordinates of each radio wave receiver respectively;

[0126] As the positioning node moves, the corresponding path loss factor n is calibrated according to the distance d to obtain the location coordinates (x, y) of the key.

[0127] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A parking system trajectory tracking and positioning method, characterized in that: The following steps are involved: According to the arrangement and installation of the vehicle, a space coordinate system of the vehicle model is established, the position coordinates of each radio wave receiver arranged on the vehicle are determined, the relative positions of the key and each radio wave receiver are determined through the radio wave transmission between the key and each radio wave receiver, and the relationship between the key and the vehicle model is obtained; the number of radio wave receivers to be arranged is at least 3; After the vehicle is started, the key transmits a starting radio wave, and the key is located according to the relative position of the key and each radio wave receiver to obtain the position coordinates of the key; During vehicle operation, the key continuously sends radio waves to each radio wave receiver, and the movement trend of the key is determined based on the trend of the light offset of the radio waves; Determine the displacement vector of each radio wave receiver according to the movement trend of the key; Perform vector synthesis on the displacement vectors of each radio wave receiver in unit time to obtain the movement direction of the vehicle in unit time and the displacement vector of the vehicle in unit time; The vehicle displacement vector in continuous unit time is integrated to obtain the vehicle's motion trajectory.

2. A parking system trajectory tracking and positioning method according to claim 1, characterized in that: The optical deviation of radio waves is calculated as: Where Δθ is the theoretical value of the optical offset of the signal, v e is the end frequency of the laser sweep, v s is the standard frequency of laser sweep, Δv=v e -v s is the laser scanning range, l is the optical path difference, and c is the speed of light in vacuum.

3. A parking system trajectory tracking and positioning method according to claim 2, characterized in that: The calculation of the optical deflection of radio waves also includes the following steps: The actual deviation of the light offset is eliminated to obtain the actual value of the light offset, which is calculated as follows: In the formula, Δθ m is the actual value of light offset, l e is the distance between the key and a radio wave receiver at the time of radio wave reception; l s The distance between a key that emits radio waves and a radio wave receiver; Let Δl = l e -l s , then: Δθ m Substituting into (1), we get: Right now In the formula, l m is the calculated distance between the key and a radio wave receiver when the radio wave is emitted after the vehicle moves, Δl is the offset of the wave path difference, Δk is the change in laser wave number corresponding to the laser sweep range, k e is the wave number corresponding to the end frequency of the sweep, Δθ err =k e is the error phase offset caused by target motion.

4. A parking system trajectory tracking and positioning method according to claim 1, characterized in that: The key position coordinates are calculated as follows: P(d)=P T -A (7) Where P T is the transmission power of the signal, and the signal strength received at the reference point at a distance of d0 from the transmitting node is A=P T -P0, n is the path loss factor; P RSSI is the received signal strength indicator, P0 is the simulated received power at the location of the transmitting node, and P(d) is the received power at the location d away from the transmitting node; The distance from the key to a single radio wave receiver is measured by equations (7) and (8). The path loss factor n varies with the movement of the positioning node and is obtained by the real vehicle calibration method: Where (x1, y1), (x2, y2), and (x3, y3) are the position coordinates of each radio wave receiver; As the positioning node moves, the corresponding path loss factor n is calibrated according to the distance d to obtain the location coordinates (x, y) of the key.

5. A parking system trajectory tracking and positioning system, comprising a controller and a key, characterized in that: The controller calls the parking system trajectory tracking and positioning method as claimed in claim 1 when calculating the parking trajectory.

6. The parking system trajectory tracking and positioning system according to claim 5, characterized in that: The optical deviation of radio waves is calculated as: Where Δθ is the theoretical value of the optical offset of the signal, ν e is the end frequency of the laser sweep, ν s is the laser sweep standard frequency, Δν=ν e -ν s is the laser frequency sweep range, l is the optical path difference, and c is the speed of light in vacuum.

7. The parking system trajectory tracking and positioning system according to claim 6, characterized in that: The calculation of the optical deflection of radio waves also includes the following steps: The actual deviation of the light offset is eliminated to obtain the actual value of the light offset, which is calculated as follows: In the formula, Δθ m is the actual value of light offset, l e is the distance between the key and a radio wave receiver at the time of radio wave reception; l s The distance between a key that emits radio waves and a radio wave receiver; Let Δl = l e -l s , then: Δθ m Substituting into (1), we get: Right now In the formula, l m is the calculated distance between the key and a radio wave receiver when the radio wave is emitted after the vehicle moves, Δl is the offset of the wave path difference, Δk is the change in laser wave number corresponding to the laser sweep range, k e is the wave number corresponding to the end frequency of the sweep, Δθ err =k e is the error phase offset caused by target motion.

8. The parking system trajectory tracking and positioning system according to claim 5, characterized in that: The key position coordinates are calculated as follows: P(d)=P T -A (7) Where P T is the transmission power of the signal, and the signal strength received at the reference point at a distance of d0 from the transmitting node is A=P T -P0, n is the path loss factor; P RSSI is the received signal strength indicator, P0 is the simulated received power at the location of the transmitting node, and P(d) is the received power at the location d away from the transmitting node; The distance from the key to a single radio wave receiver is measured by equations (7) and (8). The path loss factor n varies with the movement of the positioning node and is obtained by the real vehicle calibration method: Where (x1, y1), (x2, y2), and (x3, y3) are the position coordinates of each radio wave receiver; As the positioning node moves, the corresponding path loss factor n is calibrated according to the distance d to obtain the location coordinates (x, y) of the key.

9. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 4 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 4 are implemented.

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