A combined navigation system

Abstract

This utility model relates to the field of navigation and positioning technology, and particularly to a combined navigation system, comprising a cover plate, a housing, a first fastening screw, a second fastening screw, a third fastening screw, and hexagonal copper pillars. The cover plate and the housing are connected by the first fastening screw to form a shell assembly. An RF connector and a connector are provided on one side of the housing. An upper adapter circuit board and a lower adapter circuit board are fixedly spaced within the housing by the hexagonal copper pillars. The upper and lower adapter circuit boards are fixedly connected to the housing by the second and third fastening screws. A BeiDou dual-antenna module is fixed to the surface of the lower adapter circuit board, and an IMU (Inertial Measurement Unit) is fixed to the surface of the upper adapter circuit board. This utility model's combined navigation system achieves a dynamic balance between positioning accuracy and power consumption by integrating multi-precision IMU sensors. Combined with the BeiDou dual-antenna module and high-speed differential transmission technology, it ensures the continuity, reliability, and real-time performance of navigation data in complex environments.

Description

Technical Field

[0001] This utility model relates to the field of navigation and positioning technology, and in particular to a combined navigation system. Background Technology

[0002] With the booming development of industries such as autonomous driving and drones, navigation technology is constantly innovating, and users' requirements for the accuracy and reliability of real-time location information are increasing. The BeiDou Navigation Satellite System, together with GLONASS, GPS, and GALILEO, constitutes a global satellite navigation network. However, satellite signals are susceptible to factors such as terrain obstruction and multipath effects, leading to a decrease in positioning accuracy. Inertial Measurement Units (IMUs), with their fully autonomous navigation capabilities, can effectively compensate for the shortcomings of satellite positioning. In recent years, the development of MEMS technology has promoted the widespread application of miniaturized, low-cost IMUs in integrated navigation systems. Existing integrated navigation products typically reserve multiple IMU pads of different accuracy levels on the printed circuit board (PCB). Users need to select and solder an IMU of a specific accuracy according to their needs. This method cannot achieve dynamic switching between IMUs of different accuracy on the same device, limiting the product's adaptability and flexibility. Therefore, it is necessary to design an integrated navigation system to solve the above problems. Utility Model Content

[0003] The main objective of this invention is to provide a combined navigation system that can effectively solve the problems in the background art.

[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0005] A combined navigation system includes a cover plate, a housing, a first fastening screw, a second fastening screw, a third fastening screw, and hexagonal copper posts. The cover plate and the housing are connected by the first fastening screw to form a housing assembly. An RF connector and a connector are provided on one side of the housing. An upper adapter circuit board and a lower adapter circuit board are provided inside the housing and fixed at intervals by the hexagonal copper posts. The upper adapter circuit board and the lower adapter circuit board are fixedly connected to the housing by the second fastening screw and the third fastening screw. A Beidou dual-antenna module is fixed on the surface of the lower adapter circuit board, and an IMU inertial measurement unit is fixed on the surface of the upper adapter circuit board.

[0006] Preferably, the surface of the IMU inertial measurement unit is provided with three IMU sensors of different accuracy levels.

[0007] Preferably, a control circuit is provided between the upper and lower adapter circuit boards for receiving gating control commands and switching the IMU sensor connected to the navigation calculation circuit.

[0008] Preferably, the IMU (Inertial Measurement Unit) is connected to the upper adapter circuit board via an SPI bus, supporting hot-swappable switching of IMU sensors with different accuracies.

[0009] Preferably, data transmission between the upper and lower adapter circuit boards is achieved via high-speed differential signal lines.

[0010] Preferably, the BeiDou dual-antenna module is soldered to the surface of the lower adapter circuit board, and the antenna feed line of the BeiDou dual-antenna module is led out through an RF connector.

[0011] Preferably, the RF connector is an SMA interface for transmitting BeiDou satellite L1 / L2 frequency band signals, and the connector is a DB9 interface for outputting navigation data and receiving external control commands.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] 1. In this utility model, by integrating three precision levels of IMU sensors—ADIS16495, ICM-20948, and MPU-6050—on the surface of the IMU inertial measurement unit, and with the gating and switching function of the control circuit, the corresponding precision IMU can be automatically switched according to scenarios such as satellite signal strength and terrain environment. This solves the limitation of traditional PCB reserved pads requiring manual soldering of single-precision IMUs, and improves the product's adaptability to different usage scenarios.

[0014] 2. In this utility model, the control circuit adopts the STM32F407 main control chip, and realizes the hot switching of IMU sensor and smooth data transition within 5ms through the SPI interface, so as to avoid navigation data interruption during the switching process. The IMU and the upper adapter board transmit 16-bit raw data through a four-wire SPI bus to ensure the real-time performance of inertial data.

[0015] 3. In this utility model, the frame structure containing 16 bytes of IMU data and 32 bytes of Beidou observation data is transmitted through a high-speed differential signal line between the upper and lower adapter circuit boards. Combined with the CRC-16 verification mechanism, the integrity of the integrated navigation solution data is ensured.

[0016] 4. In this utility model, the Beidou dual antenna module uses the UM220-III-NT chipset soldered on the lower adapter circuit board, supports B1I / B2I / B3I tri-frequency signal reception, and leads out the feeder through the SMA-KFD397 RF connector to improve the satellite acquisition capability in weak signal environments.

[0017] 5. In this utility model, the cover plate and the housing form a closed shell by the first fastening screw, and the internal circuit board is fixed by hexagonal copper pillars and the second / third fastening screw to ensure structural stability. The SMA interface and DB9 interface are compatible with different terminal devices to meet diverse data access and output needs. Attached Figure Description

[0018] Figure 1 This is a first-view structural diagram of a combined navigation system according to the present invention;

[0019] Figure 2 This is a schematic diagram of the overall disassembled structure of a combined navigation system according to the present invention;

[0020] Figure 3 This is a detailed enlarged structural diagram of section A of a combined navigation system according to this utility model;

[0021] Figure 4 This is a detailed enlarged structural diagram of section B of a combined navigation system according to this utility model.

[0022] In the diagram: 1. First fastening screw; 2. Cover plate; 3. RF connector; 4. Connector; 5. Housing; 6. Upper adapter circuit board; 7. Lower adapter circuit board; 8. Beidou dual antenna module; 9. Hexagonal copper pillar; 10. Second fastening screw; 11. IMU inertial measurement unit; 12. Third fastening screw. Detailed Implementation

[0023] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below in conjunction with specific embodiments.

[0024] In the description of this utility model, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0025] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," and "connected," etc., should be interpreted broadly. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0026] Please see Figure 1-4 This utility model provides a technical solution:

[0027] A combined navigation system includes a cover plate 2, a housing 5, a first fastening screw 1, a second fastening screw 10, a third fastening screw 12, and a hexagonal copper post 9. The cover plate 2 and the housing 5 are connected by the first fastening screw 1 to form a housing assembly. An RF connector 3 and a connector 4 are provided on one side of the housing 5. An upper adapter circuit board 6 and a lower adapter circuit board 7 are provided inside the housing 5 and are fixed at intervals by the hexagonal copper post 9. The upper adapter circuit board 6 and the lower adapter circuit board 7 are fixedly connected to the housing 5 by the second fastening screw 10 and the third fastening screw 12. A Beidou dual antenna module 8 is fixed on the surface of the lower adapter circuit board 7, and an IMU inertial measurement unit 11 is fixed on the surface of the upper adapter circuit board 6.

[0028] In this embodiment, three IMU sensors with different accuracy levels are arranged on the surface of the IMU inertial measurement unit 11.

[0029] The above solution integrates three IMU sensors: ADIS16495 (0.01° / h) for high precision, ICM-20948 (1° / h) for medium precision, and MPU-6050 (10° / h) for low precision. The system can automatically switch the accuracy mode according to the external environment: the high-precision IMU is activated in scenarios with weak satellite signals, such as urban canyons, while the low-power low-precision IMU is switched in open areas, achieving a dynamic balance between positioning accuracy and power consumption.

[0030] In this embodiment, a control circuit is provided between the upper transition circuit board 6 and the lower transition circuit board 7, which is used to receive gating control commands and switch the IMU sensor connected to the navigation calculation circuit.

[0031] The above scheme uses an STM32F407 main control chip for the control circuit. It receives strobe commands via the SPI interface Mode 0 at 10MHz and completes sensor switching within 5ms. The command parsing logic is based on a state machine design, which supports smooth data transition during hot switching and ensures navigation continuity.

[0032] In this embodiment, the IMU inertial measurement unit 11 is connected to the upper adapter circuit board 6 via the SPI bus, supporting hot-swappable switching of IMU sensors with different accuracies.

[0033] The above solution employs a four-wire SPI interface (SCK, MISO, MOSI, CS), with the SPI controller on the upper adapter board 6 configured in slave mode. The IMU data frame format is 16-bit raw data + 8-bit checksum, ensuring the real-time performance and reliability of sensor data.

[0034] In this embodiment, data transmission is achieved between the upper adapter circuit board 6 and the lower adapter circuit board 7 via a high-speed differential signal line.

[0035] The above scheme ensures the accuracy of cross-board data transmission by using CRC-16 checksums, with the data frame containing 16 bytes of IMU data and 32 bytes of BeiDou observation data.

[0036] In this embodiment, the Beidou dual antenna module 8 is soldered to the surface of the lower adapter circuit board 7, and the antenna feed line of the Beidou dual antenna module 8 is led out through the radio frequency connector 3.

[0037] The above solution uses the UM220-III-NT chipset for the Beidou dual-antenna module, which supports B1I / B2I / B3I tri-frequency signal reception. The antenna feed line is led out through the SMA-KFD397 RF connector.

[0038] In this embodiment, the radio frequency connector 3 is an SMA interface used to transmit BeiDou satellite L1 / L2 frequency band signals, and the connector 4 is a DB9 interface used to output navigation data and receive external control commands.

[0039] The above solution enables the SMA interface to support signal transmission in the BeiDou B11561.098MHz / B21207.14MHz frequency bands, meeting the access requirements of different terminal devices.

[0040] It should be noted that this utility model is a combined navigation system. The working principle of this combined navigation system is as follows: the cover plate 2 and the housing 5 are connected by the first fastening screw 1 to form an outer shell assembly, which protects the internal components. The radio frequency connector 3 and connector 4 on one side of the housing 5 are respectively used to transmit BeiDou satellite L1 / L2 frequency band signals, output navigation data, and receive external control commands. The upper adapter circuit board 6 and lower adapter circuit board 7, fixed at intervals by hexagonal copper pillars 9 inside the housing, are fixedly connected to the housing 5 by the second fastening screw 10 and the third fastening screw 12. The IMU inertial measurement unit 11 fixed on the surface of the upper adapter circuit board 6 contains three IMUs with different accuracy levels. The sensor is connected to the upper adapter board 6 via an SPI bus, supporting hot-swappable switching of IMU sensors with different accuracies. The control circuit set between the upper adapter board 6 and the lower adapter board 7 can switch the IMU sensor connected to the navigation calculation circuit after receiving the gating control command. At the same time, the upper adapter board 6 and the lower adapter board 7 realize data transmission through high-speed differential signal lines. The Beidou dual antenna module 8 soldered on the surface of the lower adapter board 7 has its antenna feed line led out through the RF connector 3 for receiving satellite signals. This signal is fused with the inertial data output by the IMU inertial measurement unit 11 in the control circuit, and finally outputs navigation data through the connector 4.

[0041] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A combined navigation system, comprising a cover plate (2), a housing (5), a first fastening screw (1), a second fastening screw (10), a third fastening screw (12), and a hexagonal copper post (9), characterized in that: The cover plate (2) and the housing (5) are connected by the first fastening screw (1) to form a housing assembly. The housing (5) is provided with an RF connector (3) and a connector (4) on one side. The housing (5) is provided with an upper adapter circuit board (6) and a lower adapter circuit board (7) fixed at intervals by hexagonal copper pillars (9). The upper adapter circuit board (6) and the lower adapter circuit board (7) are fixedly connected to the housing (5) by the second fastening screw (10) and the third fastening screw (12). The surface of the lower adapter circuit board (7) is fixed with a Beidou dual antenna module (8), and the surface of the upper adapter circuit board (6) is fixed with an IMU inertial measurement unit (11).

2. The integrated navigation system according to claim 1, characterized in that: The surface of the IMU inertial measurement unit (11) is provided with three IMU sensors of different accuracy levels.

3. The integrated navigation system according to claim 1, characterized in that: A control circuit is provided between the upper transition circuit board (6) and the lower transition circuit board (7) for receiving gating control commands and switching the IMU sensor connected to the navigation calculation circuit.

4. The integrated navigation system according to claim 1, characterized in that: The IMU (inertial measurement unit) (11) is connected to the upper adapter board (6) via the SPI bus, and supports hot-swappable switching of IMU sensors with different accuracies.

5. A combined navigation system according to claim 1, characterized in that: Data transmission between the upper adapter circuit board (6) and the lower adapter circuit board (7) is achieved through a high-speed differential signal line.

6. The integrated navigation system according to claim 1, characterized in that: The Beidou dual antenna module (8) is soldered to the surface of the lower adapter circuit board (7), and the antenna feed line of the Beidou dual antenna module (8) is led out through the radio frequency connector (3).

7. A combined navigation system according to claim 1, characterized in that: The radio frequency connector (3) is an SMA interface used to transmit Beidou satellite L1 / L2 frequency band signals, and the connector (4) is a DB9 interface used to output navigation data and receive external control commands.

Images