Vehicle-mounted inertial navigation data acquisition system and vehicle-mounted inertial navigation performance test method

Abstract

The present application relates to vehicle-mounted inertial navigation data acquisition system and vehicle-mounted inertial navigation performance test method, the acquisition system includes inertial measurement unit, micro control unit and acquisition playback module, wherein: the first output end of the inertial measurement unit is connected with the input end of the acquisition playback module, the acquisition playback module acquires the inertial navigation data, the output end of the acquisition playback module is connected with the first input end of the micro control unit, the first output end of the inertial measurement unit is used to output the inertial navigation data, and the first input end of the micro control unit is used to receive the inertial navigation data.The present application only intercepts and plays back the data transmission between the vehicle-mounted terminal inertial measurement unit module and the micro control unit, multiple, multiple vehicle playback tests can be realized by acquisition, further, since the acquisition data is determined and traceable, a closed-loop test system can be formed, and the test efficiency can be improved by automatic testing.

Description

Technical Field

[0001] This invention relates to the field of vehicle inertial navigation performance testing technology, specifically to a vehicle inertial navigation data acquisition system and a vehicle inertial navigation performance testing method. Background Technology

[0002] Vehicle positioning, as a fundamental technology for both in-vehicle infotainment systems and intelligent driving systems, is a prerequisite for realizing cockpit navigation functions and high-precision positioning for intelligent driving. GNSS positioning can provide real-time, all-weather, and global navigation services. However, in practical applications, it has been found that satellite positioning performance drops rapidly in areas with weak or no signals, such as cities, tunnels, and parking garages, as well as in areas with interference. Meanwhile, inertial navigation, with its advantage of not relying on any external information and not radiating energy outwards, can compensate for the shortcomings of satellite positioning. However, this characteristic also means that inertial navigation cannot, like satellite positioning, use simulators or GNSS spectrum acquisition to generate signal sources and directly play back the signal through the antenna's radio frequency port for testing.

[0003] Existing technology discloses a GNSS signal digital acquisition and playback system, which runs an embedded operating system on a Zynq dual-core CPU. As the software component, it implements data analysis, storage, and forwarding functions. This approach retains the real-time performance advantages of the hardware implementation at the data link layer while combining the flexibility and portability of the software implementation. This solution primarily focuses on acquiring satellite positioning data and does not involve the inertial navigation or playback components. Another example is a performance testing system and method for vehicle navigation systems. This method collects road driving data from a test vehicle and compares it with a reference control module for indoor playback testing to evaluate the system's performance. A single set of data can achieve the entire test chain of "test-analysis-optimization-regression." The method briefly describes the playback of vehicle-mounted inertial navigation and the reference group inertial navigation, but it does not propose a specific scheme or implementation method for vehicle-mounted inertial navigation acquisition and playback.

[0004] Since no device can currently quickly simulate 3-axis acceleration and 3-axis angular velocity data that meet the required accuracy, vehicle-mounted inertial navigation system (INS) simulation testing primarily relies on software simulation. However, software simulation mainly operates at the application layer, focusing on algorithm and functional application testing, and cannot cover the underlying system and driver layers. It cannot address timing logic issues, hardware / software compatibility problems, and the impact of data transmission due to system lag and latency. Therefore, actual testing primarily utilizes real-vehicle road testing. Road testing offers realistic scenarios and broad coverage, but it faces challenges such as the inability to automate testing, high investment costs, and the lack of traceability and repeatability, introducing numerous uncertainties in engineering applications. Summary of the Invention

[0005] One objective of this invention is to provide an in-vehicle inertial navigation data acquisition system to achieve complete acquisition of inertial navigation data in in-vehicle inertial navigation performance testing; another objective of this invention is to provide an in-vehicle inertial navigation performance testing method to solve the technical problems of untraceability and non-repeatability in in-vehicle inertial navigation performance testing in the prior art.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] An in-vehicle inertial navigation data acquisition system includes an inertial measurement unit (IMU) and a microcontroller unit (MCU). The IMU acquires inertial navigation data, and the MCU performs calculations on the inertial navigation data. The IMU and the MCU are communicatively connected. The system also includes an acquisition and playback module.

[0008] The first output terminal of the inertial measurement unit is connected to the input terminal of the acquisition and playback module. The acquisition and playback module acquires the inertial navigation data. The output terminal of the acquisition and playback module is connected to the first input terminal of the microcontroller unit. The first output terminal of the inertial measurement unit is used to output the inertial navigation data, and the first input terminal of the microcontroller unit is used to receive the inertial navigation data.

[0009] In the aforementioned technical means, to ensure system integrity, this solution only intercepts and replays the data transmitted between the inertial measurement unit (IMU) and the microcontroller unit (MCU) of the vehicle terminal. Replay refers to returning the inertial navigation data to the vehicle for playback testing. By setting up an acquisition and playback module on the transmission link between the IMU and the MCU, an equivalent substitution is made for the data transmitted between the IMU and the MCU, without changing the communication and transmission process, thus ensuring system integrity and realizing the complete acquisition of inertial navigation data.

[0010] Furthermore, the acquisition and playback module includes an acquisition and playback unit, an external buffer resistor, and a variable resistor. The first output terminal of the inertial measurement unit is connected to one end of the external buffer resistor and one end of the variable resistor, respectively. The other end of the external buffer resistor is connected to the first input terminal of the microcontroller unit, and the other end of the variable resistor is connected to the input terminal of the acquisition and playback unit.

[0011] Furthermore, the inertial measurement unit is communicatively connected to the microcontroller unit, and also includes a clock signal line connection for transmitting clock signals, a drive signal line connection for transmitting drive signals, a control signal line connection for transmitting control signals, and a communication signal line connection for transmitting communication signals.

[0012] Furthermore, it also includes a serial port / bus tool, a first programmable control switch, a second programmable control switch, and a host computer, wherein:

[0013] The input terminal of the serial port / bus tool is connected to the connection lines of all communication connections between the inertial measurement unit and the microcontroller unit, and the output terminal of the serial port / bus tool is connected to the host computer.

[0014] The output terminal of the inertial measurement unit is connected to one end of the external buffer resistor and one end of the variable resistor through the first programmable control switch and the second programmable control switch, respectively. The output terminal of the inertial measurement unit is connected to one end of the first programmable control switch, the other end of the first programmable control switch is connected to one end of the external buffer resistor and one end of the second programmable control switch, the other end of the second programmable control switch is connected to one end of the variable resistor, and the control terminals of the first programmable control switch and the second programmable control switch are both connected to the host computer.

[0015] The host computer is also connected to the acquisition and playback device.

[0016] Furthermore, it also includes a human-machine interface, which is connected to the microcontroller unit.

[0017] This invention also provides a method for testing the performance of an in-vehicle inertial navigation system. The method utilizes the aforementioned in-vehicle inertial navigation data acquisition system and includes:

[0018] The system acquires and synchronously stores the inertial navigation data, the communication status between the inertial measurement unit and the microcontroller, and the communication delay between the acquisition and playback unit and the inertial measurement unit and the microcontroller in the acquisition and playback module.

[0019] The delay caused by acquiring and playing back the inertial navigation data is calibrated and compensated based on the communication status between the inertial measurement unit and the microcontroller, as well as the communication delay between the acquisition and playback module and the inertial measurement unit and the microcontroller.

[0020] After calibration and compensation, the inertial navigation data playback test is performed.

[0021] Among the aforementioned technical methods, the vehicle-mounted inertial navigation data acquisition system allows for a complete acquisition process requiring only a single modification, making it simple to implement. The inertial navigation data processing and transmission process of this solution is completely consistent with that of a real vehicle, enabling multiple tests from a single acquisition. It can be used for inertial navigation performance testing as well as for automated stability testing and positioning algorithm learning. Furthermore, the inertial navigation data can be used in conjunction with GNSS positioning data and upper-level navigation applications for functional testing, making it widely applicable.

[0022] Match the voltage of the acquisition and playback unit with that of the inertial measurement unit;

[0023] The host computer controls the acquisition and playback device to acquire the inertial navigation data and record it to the host computer.

[0024] Furthermore, obtaining the communication status between the inertial measurement unit and the microcontroller unit includes the following steps:

[0025] The communication status between the inertial measurement unit and the microcontroller is monitored, and the communication status and the inertial navigation data collected by the acquisition and playback device are synchronously stored in the host computer.

[0026] Furthermore, obtaining the communication delay between the acquisition / playback unit, the inertial measurement unit, and the microcontroller unit includes the following steps:

[0027] The host computer controls the inertial measurement unit to establish a communication connection with the microcontroller unit. The signal from the inertial measurement unit is processed by the microcontroller unit and becomes the first transmission signal.

[0028] The host computer detects the communication status between the inertial measurement unit and the microcontroller. When the communication status between the inertial measurement unit and the microcontroller meets the transmission conditions, the host computer controls the inertial measurement unit to disconnect from the microcontroller and controls the acquisition and playback unit to establish a communication connection with the microcontroller. The signal from the acquisition and playback unit enters the microcontroller for processing and becomes the second transmission signal.

[0029] The host computer monitors the delays of the first and second transmission signals and records them as communication delays generated between the acquisition and playback unit, the inertial measurement unit, and the microcontroller unit.

[0030] Furthermore, the inertial navigation data playback test is performed, including the following steps:

[0031] The host computer controls the inertial measurement unit to establish a communication connection with the microcontroller unit;

[0032] The host computer monitors the communication status between the inertial measurement unit and the microcontroller unit, and prepares the first set of inertial navigation data in advance according to the communication delay. When the communication status between the inertial measurement unit and the microcontroller unit meets the transmission conditions, the data is immediately transmitted for playback testing.

[0033] The beneficial effects of this invention are:

[0034] This invention achieves an equivalent substitution of inertial navigation data through real-vehicle dynamic scene acquisition and playback, ensuring the integrity of the transmission link of the on-board inertial measurement unit during testing. This overcomes the shortcomings of software simulation data, which cannot cover the underlying layers and is unsuitable for system testing. Furthermore, because this invention intercepts and replays the data transmitted between the on-board terminal inertial measurement unit and the microcontroller unit, the noise characteristics, wander properties, and accuracy characteristics of the acquired inertial navigation data are deterministic. Simultaneously, real-vehicle acquisition ensures that the inertial navigation data matches the vehicle's position, attitude, trajectory, and state, giving it practical significance rather than being a simple mathematical simulation model. When playing back the acquired inertial navigation data for testing, there is no need for hardware simulation of the inertial navigation data. This avoids the technical problem of hardware simulation lacking the equipment to simulate high-precision 3-axis acceleration and 3-axis angular velocity data in inertial navigation data, and also avoids the complex matching process between inertial navigation data and the vehicle's position, attitude, trajectory, and state. A single data acquisition allows for multiple, multi-vehicle playback tests. Furthermore, because the acquired data is deterministic and traceable, it can form a closed-loop testing system for automated testing, improving efficiency. On the other hand, simulating road tests through data acquisition and playback instead of actual vehicle road tests reduces costs for tasks requiring long-term or repeated testing, such as version iterations, reproducing occasional issues, and stability testing. Moreover, the solution provided by this invention is highly applicable to real-vehicle data acquisition using serial communication and CAN communication. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the module connection of an in-vehicle inertial navigation data acquisition system provided in an embodiment of the present invention;

[0036] Figure 2 This is a schematic diagram of the acquisition and playback module provided in an embodiment of the present invention;

[0037] Figure 3 A schematic diagram of module connections for another vehicle-mounted inertial navigation data acquisition system provided in an embodiment of the present invention;

[0038] Figure 4 A schematic diagram illustrating the modification of the vehicle-mounted terminal provided in an embodiment of the present invention;

[0039] Figure 5 This is a schematic diagram illustrating the specific connection of an in-vehicle inertial navigation data acquisition system provided in an embodiment of the present invention;

[0040] Figure 6 This is a flowchart illustrating a method for testing the performance of vehicle-mounted inertial navigation, as provided in an embodiment of the present invention. Detailed Implementation

[0041] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0042] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0043] This embodiment provides an in-vehicle inertial navigation data acquisition system, including an inertial measurement unit (IMU) and a microcontroller unit (MCU). The IMU acquires inertial navigation data, and the MCU processes the inertial navigation data. The IMU and the MCU are communicatively connected. Figure 1 As shown, the acquisition system also includes an acquisition playback module, wherein:

[0044] The first output terminal of the inertial measurement unit is connected to the input terminal of the acquisition and playback module. The acquisition and playback module acquires the inertial navigation data. The output terminal of the acquisition and playback module is connected to the first input terminal of the microcontroller unit. The first output terminal of the inertial measurement unit is used to output the inertial navigation data, and the first input terminal of the microcontroller unit is used to receive the inertial navigation data.

[0045] In this embodiment, while ensuring the system remains as complete as possible, the collected inertial navigation data is replayed according to the existing links of the vehicle terminal to ensure the integrity of the vehicle terminal and to ensure maximum reproducibility during the full-link inertial navigation test. To ensure system integrity, this invention only intercepts and replays the data transmitted between the inertial measurement unit module and the microcontroller unit of the vehicle terminal. For the patch-type inertial measurement unit module, this invention only collects and replays the communication data line between the microcontroller unit and the patch; its clock and other non-data lines still communicate according to the connection method of the vehicle terminal. This embodiment of the invention only makes an equivalent substitution for the data transmission between the two modules without changing its communication process and transmission process, thus ensuring the integrity of the system. For the independent integrated controller solution of the inertial measurement unit, its external output data can be directly collected, which is simpler to implement, and the data collection in this embodiment of the invention is also applicable.

[0046] In this embodiment, the inertial measurement unit has two functions: first, it is an external sensor for vehicle navigation, providing attitude data for vehicle navigation; second, it is a signal source for the data collected in this embodiment, and by collecting its attitude data (acceleration and angular velocity data, which is the inertial navigation data in this embodiment), it can be used to test other vehicles using the same protocol or to collect data for multiple playback tests.

[0047] The microcontroller unit is used to calculate specific acceleration and angle data from the data of the inertial measurement unit and encapsulate it according to the protocol for use by upper-layer applications.

[0048] In a further embodiment, such as Figure 2 As shown, the acquisition and playback module includes an acquisition and playback unit, an external buffer resistor, and a variable resistor. The first output terminal of the inertial measurement unit is connected to one end of the external buffer resistor and one end of the variable resistor, respectively. The other end of the external buffer resistor is connected to the first input terminal of the microcontroller unit, and the other end of the variable resistor is connected to the input terminal of the acquisition and playback unit.

[0049] In this embodiment, the external buffer resistor is used to replace the original vehicle terminal buffer resistor, for buffering when data fluctuates and for voltage division to avoid damage to the microcontroller unit (such as RS232 serial communication) or for network matching (such as CAN communication).

[0050] The variable resistor is mainly used to adjust the voltage to ensure voltage matching between the acquisition and playback unit and the inertial measurement unit, thus ensuring stable data acquisition and playback.

[0051] The acquisition and playback unit is used to acquire and play back attitude data and clock data of the vehicle-mounted inertial measurement unit.

[0052] In a further embodiment, the inertial measurement unit is communicatively connected to the microcontroller unit, and further includes a clock signal line connection for transmitting clock signals, a drive signal line connection for transmitting drive signals, a control signal line connection for transmitting control signals, and a communication signal line connection for transmitting communication signals.

[0053] In this embodiment, the microcontroller unit is also connected to the inertial measurement unit via clock signal lines, drive signal lines, control signal lines, and communication signal lines to ensure its normal operation.

[0054] In a further embodiment, such as Figure 3 As shown, it also includes a serial port / bus tool, a first programmable control switch, a second programmable control switch, and a host computer, wherein:

[0055] The input terminal of the serial port / bus tool is connected to the connection lines of all communication connections between the inertial measurement unit and the microcontroller unit, and the output terminal of the serial port / bus tool is connected to the host computer.

[0056] The output terminal of the inertial measurement unit is connected to one end of the external buffer resistor and one end of the variable resistor through the first programmable control switch and the second programmable control switch, respectively. The output terminal of the inertial measurement unit is connected to one end of the first programmable control switch, the other end of the first programmable control switch is connected to one end of the external buffer resistor and one end of the second programmable control switch, the other end of the second programmable control switch is connected to one end of the variable resistor, and the control terminals of the first programmable control switch and the second programmable control switch are both connected to the host computer.

[0057] The host computer is also connected to the acquisition and playback device.

[0058] In this embodiment, the programmable control switch is mainly connected to the signal output terminal of the terminal inertial measurement unit and the acquisition and playback unit. The computer controls its opening and closing to control the inertial navigation data transmission link. Different switch combinations realize the three functions of inertial measurement unit data acquisition, playback data delay calibration and data playback.

[0059] The serial port / bus tool is used to detect all communication links of all microcontrollers and vehicle-mounted inertial measurement units and generate output signal markers of vehicle-mounted inertial measurement units in real time. It is used to record the communication status of other links when the vehicle-mounted inertial measurement unit outputs data and to serve as the timing for the computer to control the output of the acquisition and playback device.

[0060] The host computer has control software that controls a programmable switch to switch between three modes in this embodiment: data acquisition, playback data delay calibration, and data playback. In acquisition mode, the communication status is recorded through a serial port / bus tool to determine the playback timing. In playback data delay calibration mode, the delay time can be calibrated by comparing the playback data with the output data of the inertial measurement unit. In playback mode, it is mainly used to control the output timing of the acquisition and playback unit.

[0061] In a further embodiment, a human-machine interface is also included, which is connected to the microcontroller unit.

[0062] In this implementation, the human-machine interface is mainly used to display inertial navigation-related human-machine interaction information, and to avoid collecting inertial measurement unit data that does not meet the requirements through visualized data and function checks.

[0063] In specific embodiments, such as Figure 4The diagram shown is a specific connection schematic of an in-vehicle inertial navigation data acquisition system according to an embodiment of the present invention. It should be noted that... Figure 4 This diagram illustrates the connection of an in-vehicle inertial navigation data acquisition system using the RSS232 serial communication protocol. It only shows the connection between the microcontroller unit and the inertial measurement unit. The specific number of transmission signal lines and the actual connection method of the buffer resistors need to be matched to the communication method of the microcontroller unit and the inertial measurement unit. When using CAN communication, the transmitted signals correspond to CAN_H and CAN_L respectively, and the buffer resistor is simply a 120-ohm terminating resistor connecting CAN_H and CAN_L. When using I2C serial communication, it corresponds to the transmission of data lines and clock signal lines, and other communication methods follow the same principle. In summary, the connection may differ depending on the communication method of the inertial measurement unit and the microcontroller unit, but this does not affect the application of this method and invention.

[0064] like Figure 4 and Figure 5 As shown, first, remove the buffer resistors (R1 and R2) from the data transmission lines connecting the original vehicle's inertial measurement unit (IMU) and microcontroller unit (MCU). Then, after removing the buffer resistors, the data transmission lines of the IMU and MCU are disconnected, but other lines remain connected normally. For CAN communication and other lines without buffer resistors, simply disconnect the corresponding transmission line. Finally, cutting off the data transmission lines will create several open ports, such as... Figure 4 and Figure 5 Ports A1, A2, A3, and A4 are used to connect to the acquisition and playback module, enabling simulated road testing. Since there are two signal lines between the inertial measurement unit and the microcontroller unit, the acquisition and playback module has four programmable control switches (K1, K2, K3, K4), two external buffer resistors (R1' and R2'), and two variable resistors (R). Port A1 is connected to one end of programmable control switch K4. The other end of programmable control switch K4 is connected to one end of external buffer resistor R1' and one end of programmable control switch K1, respectively. The other end of external buffer resistor R1' is connected to port A2. The other end of programmable control switch K1 is connected to a variable resistor, and the other end of this variable resistor is connected to the acquisition and playback unit.

[0065] Port A3 is connected to one end of programmable control switch K3. The other end of programmable control switch K3 is connected to one end of external buffer resistor R2' and one end of programmable control switch K2. The other end of external buffer resistor R2' is connected to port A4. The other end of programmable control switch K2 is connected to a variable resistor. The other end of the variable resistor is connected to the acquisition and playback unit.

[0066] The serial port / bus tool is connected to port A2, clock signal line, drive signal line, control signal line and communication signal line respectively;

[0067] The host computer is connected to four programmable control switches (K1, K2, K3, K4), a data acquisition and playback unit, and a serial port / bus tool.

[0068] This embodiment provides a method for testing the performance of vehicle-mounted inertial navigation, such as... Figure 6 As shown, the vehicle-mounted inertial navigation performance testing method utilizes the aforementioned vehicle-mounted inertial navigation data acquisition system. The vehicle-mounted inertial navigation performance testing method includes:

[0069] Acquire the inertial navigation data, the communication status between the inertial measurement unit and the microcontroller, and the communication delay between the acquisition and playback device and the inertial measurement unit and the microcontroller, and store them synchronously;

[0070] The delay caused by acquiring and playing back the inertial navigation data is calibrated and compensated based on the communication status between the inertial measurement unit and the microcontroller, as well as the communication delay between the acquisition and playback device and the inertial measurement unit and the microcontroller.

[0071] After calibration and compensation, the inertial navigation data playback test is performed.

[0072] In a further embodiment, acquiring the inertial navigation data includes the following steps:

[0073] Match the voltage of the acquisition and playback unit with that of the inertial measurement unit;

[0074] In this embodiment, the acquisition and playback module includes an acquisition and playback unit, an external buffer resistor, and a variable resistor. The first output terminal of the inertial measurement unit is connected to one end of the external buffer resistor and one end of the variable resistor. The other end of the external buffer resistor is connected to the first input terminal of the microcontroller unit, and the other end of the variable resistor is connected to the input terminal of the acquisition and playback unit. In this embodiment, the voltage of the acquisition and playback unit is matched to that of the inertial measurement unit by adjusting the resistance value of the variable resistor.

[0075] The host computer controls the acquisition and playback device to acquire the inertial navigation data and record it to the host computer.

[0076] In this embodiment, the vehicle-mounted inertial navigation data acquisition system includes a serial port / bus tool, a first programmable control switch, a second programmable control switch, and a host computer. The input terminal of the serial port / bus tool is connected to all communication lines between the inertial measurement unit and the microcontroller unit, and the output terminal of the serial port / bus tool is connected to the host computer. The output terminal of the inertial measurement unit is connected to one end of an external buffer resistor and one end of a variable resistor via the first and second programmable control switches, respectively. The output terminal of the inertial measurement unit is connected to one end of the first programmable control switch, the other end of the first programmable control switch is connected to one end of the external buffer resistor and one end of the second programmable control switch, and the other end of the second programmable control switch is connected to one end of the variable resistor. The control terminals of both the first and second programmable control switches are connected to the host computer. The host computer is also connected to the acquisition and playback unit. In this embodiment, the host computer controls the first and second programmable control switches to close, at which point the acquisition and playback unit acquires the inertial navigation data and records it to the host computer.

[0077] In a further embodiment, obtaining the communication status between the inertial measurement unit and the microcontroller unit includes the following steps:

[0078] The communication status between the inertial measurement unit and the microcontroller is monitored, and the communication status and the inertial navigation data collected by the acquisition and playback device are synchronously stored in the host computer.

[0079] In this embodiment of the application, the communication status between the inertial measurement unit and the microcontroller unit is monitored through the serial port / bus tool.

[0080] In a specific embodiment, the acquisition and playback device, consisting of programmable control switches (K1, K2, K3, K4), two external buffer resistors (R1' and R2'), two variable resistors, and an acquisition and playback unit, is first arranged as follows: Figure 5The connection shown is made to the acquisition and playback ports A1, A2, A3, and A4. The communication status of the inertial measurement unit (IMU) and microcontroller unit (MCU) during data transmission is monitored and recorded by a serial port / bus tool and stored in the host computer. Next, the resistance of the variable resistor is adjusted to match the voltage between the acquisition / playback unit and the IMU. Then, the host computer controls all four programmable control switches (K1, K2, K3, K4) to close. At this point, the data transmitted from the IMU to the MCU is split into two paths: one path is transmitted to the MCU to support upper-level functional applications and is displayed visually through a human-machine interface for monitoring and recording of inertial navigation data, ensuring data accuracy and availability, and facilitating comparison with playback results for problem analysis. The other path, along with the clock signal, is acquired and recorded by the acquisition / playback unit. Simultaneously, the host computer monitors the communication status of the IMU and MCU via a serial port / bus tool and stores the status of the acquisition / playback unit in the computer. Finally, after completing the above preparations, the dynamic data of the actual vehicle can be acquired and stored.

[0081] In a further embodiment, acquiring the communication delay between the acquisition / playback unit and the inertial measurement unit and the microcontroller unit includes the following steps:

[0082] The host computer controls the inertial measurement unit to establish a communication connection with the microcontroller unit. The signal from the inertial measurement unit is processed by the microcontroller unit and becomes the first transmission signal.

[0083] In this embodiment of the application, the host computer controls the first programmable control switch to close and the second programmable control switch to open, thereby enabling the inertial measurement unit to establish a communication connection with the microcontroller unit;

[0084] The host computer detects the communication status between the inertial measurement unit and the microcontroller. When the communication status between the inertial measurement unit and the microcontroller meets the transmission conditions, the host computer controls the inertial measurement unit to disconnect from the microcontroller and controls the acquisition and playback unit to establish a communication connection with the microcontroller. The signal from the acquisition and playback unit enters the microcontroller for processing and becomes the second transmission signal.

[0085] In this embodiment of the application, the host computer controls the first programmable control switch to open and the second programmable control switch to close, thereby disconnecting the inertial measurement unit from the microcontroller unit and controlling the acquisition and playback device to establish a communication connection with the microcontroller unit.

[0086] The host computer monitors the delays of the first and second transmission signals and records them as communication delays generated between the acquisition and playback unit, the inertial measurement unit, and the microcontroller unit.

[0087] In this embodiment, since the data encoding and write storage operations during the acquisition process take t1, and the read storage and decoding operations during playback take t2, the direct communication delay t1+t2 between the inertial measurement unit and the microcontroller is calculated using the acquisition and playback scheme. This time is related to the performance of the acquisition and playback unit and needs to be compensated. The communication delay t1+t2 is obtained by comparing the time difference between the acquisition and playback link data (the second transmission signal) and the original direct communication link data (i.e., the first transmission signal). In a specific embodiment, due to the need to store data during acquisition, generate and play back data during playback, and various system status monitoring, there is a certain delay. Since inertial navigation data is real-time data, it is necessary to calibrate and compensate for the time delay. First, the programmable control switches (K1, K2, K3, K4), two external buffer resistors (R1' and R2'), two variable resistors, and the acquisition and playback unit are arranged according to... Figure 5 The connection method involves connecting to acquisition and playback ports A1, A2, A3, and A4 (these ports can be reused if application version iteration testing, stability testing, and durability testing are being performed on the original acquisition vehicle). Next, the host computer controls the programming control switches K1 and K2 to open, and K3 and K4 to close. At this time, only the signal from the inertial measurement unit (IMU) enters the microcontroller for processing, and the acquisition and playback data is truncated. Then, the host computer detects the status of the serial port / bus tool. When the communication status of the IMU and the microcontroller meets the transmission conditions, the host computer immediately controls the programming control switches K1 and K2 to close, and K3 and K4 to open. At this time, the acquisition and playback device outputs data. Next, the host computer monitors and records the delay of the two transmission signals under the same status. Finally, this delay, along with the communication status recorded by the host computer and the acquisition and playback device status, forms the final control data for the acquisition and playback device, further controlling the playback timing. In this embodiment, the system can also be trained based on loop closure detection and deep learning. When similar inertial measurement units and acquisition / playback units are detected, existing calibration values ​​can be directly called to save testing time.

[0088] In a further embodiment, the inertial navigation data playback test includes the following steps:

[0089] The host computer controls the inertial measurement unit to establish a communication connection with the microcontroller unit, that is, to close the first programmable control switch and open the second programmable control switch;

[0090] The host computer monitors the communication status between the inertial measurement unit and the microcontroller unit through the serial port / bus tool, and prepares the first set of inertial navigation data in advance according to the communication delay. When the communication status between the inertial measurement unit and the microcontroller unit meets the transmission conditions, the data is immediately transmitted for playback testing.

[0091] In a specific embodiment, playback testing can be performed after calibration. Next, the host computer controls the programming switches K1 and K2 to close, and K3 and K4 to open. At this time, the inertial measurement unit (IMU) can output data, but it is truncated by K3 and K4. The output data from the acquisition and playback unit can be successfully transmitted to the microcontroller unit through the closed K1 and K2 switches. Then, the host computer monitors the communication status between the IMU and the microcontroller unit via a serial port / bus tool. Since the acquired data is deterministic, the host computer controls the acquisition and playback unit to prepare the first set of data in advance based on the calibration status. When the transmission conditions are met, the data is immediately transmitted for playback testing.

[0092] The above embodiments achieve the switching of three functions—data acquisition, playback data delay calibration, and data playback—of the onboard inertial measurement unit (IMU) through different on / off combinations of a computer-controlled programmable switch. By calibrating the playback data delay and marking the status of the IMU and microcontroller data transmission, the acquisition and playback functions effectively replace the data reported by the IMU. This allows for the storage and playback of dynamic test data for automated test development, navigation performance verification, etc., without the need for road testing, reducing testing costs, improving testing efficiency, and facilitating problem tracing.

[0093] The above embodiments are merely preferred embodiments provided to fully illustrate the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention.

Claims

1. A vehicle-mounted inertial navigation data acquisition system, comprising an inertial measurement unit and a microcontroller unit, wherein the inertial measurement unit acquires inertial navigation data, the microcontroller unit performs calculations on the inertial navigation data, and the inertial measurement unit is communicatively connected to the microcontroller unit, characterized in that, It also includes a capture and playback module, in which: The first output terminal of the inertial measurement unit is connected to the input terminal of the acquisition and playback module. The acquisition and playback module acquires the inertial navigation data. The output terminal of the acquisition and playback module is connected to the first input terminal of the microcontroller unit. The first output terminal of the inertial measurement unit is used to output the inertial navigation data, and the first input terminal of the microcontroller unit is used to receive the inertial navigation data. The acquisition and playback module includes an acquisition and playback unit, an external buffer resistor, and a variable resistor. The first output terminal of the inertial measurement unit is connected to one end of the external buffer resistor and one end of the variable resistor, respectively. The other end of the external buffer resistor is connected to the first input terminal of the microcontroller unit, and the other end of the variable resistor is connected to the input terminal of the acquisition and playback unit.

2. The vehicle-mounted inertial navigation data acquisition system according to claim 1, characterized in that, The inertial measurement unit is communicatively connected to the microcontroller unit, and also includes a clock signal line connection for transmitting clock signals, a drive signal line connection for transmitting drive signals, a control signal line connection for transmitting control signals, and a communication signal line connection for transmitting communication signals.

3. The vehicle-mounted inertial navigation data acquisition system according to claim 2, characterized in that, It also includes a serial port / bus tool, a first programmable control switch, a second programmable control switch, and a host computer, wherein: The input terminal of the serial port / bus tool is connected to the connection lines of all communication connections between the inertial measurement unit and the microcontroller unit, and the output terminal of the serial port / bus tool is connected to the host computer. The output terminal of the inertial measurement unit is connected to one end of the external buffer resistor and one end of the variable resistor through the first programmable control switch and the second programmable control switch, respectively. The output terminal of the inertial measurement unit is connected to one end of the first programmable control switch, the other end of the first programmable control switch is connected to one end of the external buffer resistor and one end of the second programmable control switch, the other end of the second programmable control switch is connected to one end of the variable resistor, and the control terminals of the first programmable control switch and the second programmable control switch are both connected to the host computer. The host computer is also connected to the acquisition and playback device.

4. The vehicle-mounted inertial navigation data acquisition system according to claim 3, characterized in that, It also includes a human-machine interface, which is connected to the microcontroller unit.

5. A method for testing the performance of vehicle-mounted inertial navigation, characterized in that, The vehicle-mounted inertial navigation performance testing method uses the vehicle-mounted inertial navigation data acquisition system according to any one of claims 1-4, and the vehicle-mounted inertial navigation performance testing method includes: The system acquires and synchronously stores the inertial navigation data, the communication status between the inertial measurement unit and the microcontroller, and the communication delay between the acquisition and playback module and the inertial measurement unit and the microcontroller. The delay caused by acquiring and replaying the inertial navigation data is calibrated and compensated based on the communication status between the inertial measurement unit and the microcontroller unit, as well as the communication delay between the acquisition and playback module and the inertial measurement unit and the microcontroller unit. After calibration and compensation, the inertial navigation data playback test is performed.

6. The vehicle-mounted inertial navigation performance testing method according to claim 5, characterized in that, The acquisition of the inertial navigation data includes the following steps: Match the voltage of the acquisition and playback unit with that of the inertial measurement unit; The host computer controls the acquisition and playback device to acquire the inertial navigation data and record it to the host computer.

7. The vehicle-mounted inertial navigation performance testing method according to claim 5, characterized in that, Obtaining the communication status between the inertial measurement unit and the microcontroller unit includes the following steps: The communication status between the inertial measurement unit and the microcontroller is monitored, and the communication status and the inertial navigation data collected by the acquisition and playback device are synchronously stored in the host computer.

8. The vehicle-mounted inertial navigation performance testing method according to claim 5, characterized in that, The steps for obtaining the communication delay between the acquisition and playback unit, the inertial measurement unit, and the microcontroller unit include: The inertial measurement unit communicates with the microcontroller unit via a host computer. The signal from the inertial measurement unit is processed by the microcontroller unit and becomes the first transmission signal. The host computer detects the communication status between the inertial measurement unit and the microcontroller. When the communication status between the inertial measurement unit and the microcontroller meets the transmission conditions, the host computer controls the inertial measurement unit to disconnect from the microcontroller and controls the acquisition and playback unit to establish a communication connection with the microcontroller. The signal from the acquisition and playback unit enters the microcontroller for processing and becomes the second transmission signal. The host computer monitors the delays of the first and second transmission signals and records them as communication delays between the acquisition and playback unit, the inertial measurement unit, and the microcontroller unit.

9. The vehicle-mounted inertial navigation performance testing method according to claim 5, characterized in that, The inertial navigation data playback test includes the following steps: The inertial measurement unit communicates with the microcontroller unit via a host computer. The host computer monitors the communication status between the inertial measurement unit and the microcontroller unit, and prepares the first set of inertial navigation data in advance according to the communication delay. When the communication status between the inertial measurement unit and the microcontroller unit meets the transmission conditions, the data is immediately transmitted for playback testing.

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