Semi-physical simulation test method for strapdown infrared seeker based on two-axis turntable

Abstract

The invention belongs to the technical field of semi-physical simulation system tests, and relates to a strapdown infrared seeker semi-physical simulation test method based on a two-axis turntable. The method is realized based on a two-axis turntable, an infrared target simulator is mounted on a pitching frame of the two-axis turntable, and a seeker is mounted on a seeker mounting surface on a central base of the two-axis turntable and is always in a static state; the simulation model computer transmits azimuth and pitching information which is calculated in real time to the two-axis rotary table and transmits missile-target distance and sight angle information which is calculated in real time to the medium-wave infrared target simulator, and the rotary table drives the infrared target simulator to simulate relative movement and position relation between an aircraft and a target. A lightweight framework is adopted, and the problems that due to the seeker structure and the working mode, a traditional five-axis seeker rotary table cannot be used, the simulated tail end falling angle is too large, and the angle of the rotary table exceeds the limit are solved.

Description

Technical Field

[0001] This invention belongs to the field of hardware-in-the-loop simulation system testing technology, and provides a hardware-in-the-loop simulation test method for a strapdown infrared seeker based on a two-axis turntable. Background Technology

[0002] Traditional hardware-in-the-loop (HIL) simulation of infrared guidance and control systems requires a five-axis turntable (three-axis plus two-axis structure) to simulate the seeker's motion attitude and the relative position of the missile and target. The three axes serve as the attitude motion platform, housing the seeker and providing it with attitude information in the heading, pitch, and roll directions. The two axes house an infrared target simulator, simulating the dynamic changes in the relative position of the seeker and the infrared target in the heading and pitch directions. Traditional five-axis turntables are expensive and complex. This two-axis turntable-based strapdown infrared seeker HIL simulation method replaces the five-axis turntable required in conventional simulations. By effectively transforming the relative position of the missile and target, and utilizing the change in the target's line-of-sight elevation angle relative to the aircraft's attitude angle after coordinate transformation, an equivalent guidance and detection angle environment is constructed, thus completing the HIL simulation of the strapdown infrared seeker. This system is the first of its kind in the industry, representing a breakthrough and innovation. It is simple in form, low in cost, and effectively reduces the complexity, construction cost, and maintenance difficulty of simulation systems. Summary of the Invention

[0003] Purpose of the invention This invention discloses a semi-physical simulation test method for a strapdown infrared seeker based on a two-axis turntable. The seeker is fixed at the center of the rotating base of the two-axis turntable, and the infrared target simulator is mounted on the two-axis turntable, ensuring that the detection center of the infrared seeker, the imaging projection center of the target simulator, and the axis of rotation of the turntable are completely coincident. By equivalently transforming the relative motion position relationship between the missile and the target, the motion of the two-axis turntable is used to simulate the changes in the seeker's heading and pitch frame angles relative to the target, thereby completing the semi-physical simulation of the strapdown infrared seeker.

[0004] Technical solution A hardware-in-the-loop simulation method for a strapdown infrared seeker based on a two-axis turntable is proposed. The infrared target simulator is mounted on the pitch frame of the two-axis turntable, and the seeker is mounted on the seeker mounting surface on the central base of the two-axis turntable, always remaining stationary. The simulation model computer transmits the real-time calculated azimuth and pitch information to the two-axis turntable, and transmits the real-time calculated missile-target distance and line-of-sight angle information to the mid-wave infrared target simulator. The turntable drives the infrared target simulator to simulate the relative motion and positional relationship between the aircraft and the target.

[0005] Furthermore, the specific steps are as follows: Step 1: Simulate the aircraft's heading and pitch motion attitude during flight, as well as the relative motion between the projectile and the target. Step 2: Calculation of control commands for the mid-wave infrared target simulator and simulation of roll angle in the infrared target simulator; Step 3: Final large-angle simulation.

[0006] Further, in step one, the flight attitude of the aircraft in the heading and pitch directions, as well as the relative motion between the missile and the target, are simulated during flight. The specific calculation method is as follows: Taking the heading, pitch, and roll angles of the navigation system as inputs, the three angles of the missile system are output through the navigation system-to-missile system matrix function conversion; then, taking the missile-target distances in the three directions of northeast, south, and sky, and the three converted angles as inputs, the results are converted into frame angles in two directions, first heading and then pitch, through a multiplication matrix, for control of the two-axis turntable.

[0007] Further, in step two, the control command calculation of the mid-wave infrared target simulator and the roll angle simulation in the infrared target simulator are as follows: the mid-wave infrared target simulator receives the missile-target distance and line-of-sight angle sent to the real-time network by the simulation model computer after calculation, and generates various targets and their area scenes corresponding to the flight process, providing simulated targets for the seeker to track. The flight roll angle calculated in real time by the simulation model computer is transmitted to the infrared target simulator via a reflective memory network to simulate the relative roll motion and positional relationship between the missile and the target. The specific calculation method is as follows: using the initial roll angle as the initial value for integration, the angular velocity is integrated over time.

[0008] Furthermore, step three, the final large-angle simulation, specifically involves: Before the target distance is X km, the simulation model computer sends a 0 value to the turntable via a reflective memory network, keeping it stationary. After X km, the actual calculated value is sent to control the turntable movement. A smooth transition function is used to smooth the transition to the actual simulation value within a certain time. Then, terminal guidance simulation is performed according to the actual calculated value. The specific calculation method is as follows: In the initialization module, a time variable T_HW is set and assigned a value of 1000. When the real-time time is less than T_HW, the two-axis turntable control is always 0, and the turntable is stationary. When the target distance is less than X km, the current time value is assigned to the variable T_HW. Within the time period T_HW+X, the heading and pitch control values ​​of the two-axis turntable smoothly transition to the actual simulation value through an exponential law.

[0009] Furthermore, the communication method between the simulation model computer and the two-axis turntable and infrared target simulator is as follows: the two-axis turntable and the mid-wave infrared target simulator communicate with the simulation model computer in real time through the VMIC reflective memory real-time network system.

[0010] Furthermore, the network system consists of a fiber optic data switch, a real-time fiber optic card, and fiber optic communication cables. The simulator sends real-time calculation data to the two-axis turntable and infrared target simulator at a set address through the encapsulation function rfm_write_floats, and then reads the actual movement position data of the turntable at a specified address through the rfm_read_floats function.

[0011] Furthermore, based on the relevant dimensions of the two-axis rotary table, the seeker head, and the mid-wave infrared target simulator, and taking into account the actual simulation requirements, tooling for the two-axis rotary table and the mid-wave infrared target simulator is designed for installation during simulation.

[0012] Technical effect This method, a first in the industry, revolutionizes conventional hardware-in-the-loop simulation testing methods for seekers by employing a lightweight architecture. It addresses the limitations of traditional five-axis seeker turntables due to their structure and operating mode, as well as the issue of excessive simulation end-point angles exceeding turntable limits. Based on the principle of cost reduction and efficiency improvement, this method offers lower construction costs and easier maintenance compared to traditional complex five-axis turntables, significantly reducing model development costs. The method is simple, efficient, practical, and simplifies the testing process, reducing labor costs. Furthermore, it boasts strong compatibility, meeting not only traditional model development needs but also the requirements for hardware-in-the-loop simulation of large-size or special-operational seekers, thus possessing broad application potential. Attached Figure Description

[0013] Figure 1 This is a schematic diagram illustrating the implementation of the method of the present invention; Note: 1: Seeker mounting surface; 2: Elevation frame (mounting surface of mid-wave infrared target simulator). Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions in the embodiments of this invention will be described in more detail below. In the examples, the same or similar reference numerals denote the same or similar components or elements having the same or similar functions throughout. The described embodiments are some, but not all, of the embodiments of this invention. The embodiments described below with reference to reference are exemplary and intended to explain this invention, and should not be construed as limiting the invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention. The embodiments of this invention will be described in detail below.

[0015] A hardware-in-the-loop simulation method for a strapdown infrared seeker based on a two-axis turntable is proposed. By effectively transforming the relative motion position relationship between the missile and the target, and utilizing the change in the elevation angle of the target's line of sight relative to the attitude angle of the aircraft after coordinate transformation by simulating the motion of the two-axis turntable, a realistic spatial position simulation environment is provided for the seeker, thereby completing the hardware-in-the-loop simulation of the strapdown infrared seeker.

[0016] The specific implementation steps are as follows: 1) Based on the limitations of existing simulation technology and simulation requirements, a hardware-in-the-loop simulation method for a strapdown infrared seeker based on a two-axis turntable is designed. 2) Design the structure of the two-axis turntable and the installation method of the seeker head and mid-wave infrared target simulator; 3) Design the communication interface and tooling for the two-axis rotary table and infrared target simulator; 4) Design and solve the simulation model, calculate the relative motion angle between the seeker and the target, simulate the real-time scene, and send the relevant data to the two-axis turntable and the mid-wave infrared target simulator; 5) Install the strapdown infrared seeker and the mid-wave infrared target simulator; 6) Conduct a full system communication check; 7) Set the initial parameters for the two-axis turntable and mid-wave infrared target simulator; 8) The product is powered on, and the system initiates the launch process; 9) The simulation model enters the simulation loop, completes the strapdown attitude calculation and line-of-sight angle information calculation, and after coordinate transformation, sends the angle change of the target line-of-sight elevation angle relative to the aircraft attitude angle to the two-axis turntable in real time. The movement of the two-axis turntable provides a real spatial position simulation environment for the seeker.

[0017] Example A hardware-in-the-loop simulation test method for a strapdown infrared seeker based on a two-axis turntable is proposed. The method utilizes a two-axis turntable, with the infrared target simulator installed on... Figure 1 The guide head is mounted on the pitch frame 2 of the two-axis rotary table. Figure 1 The seeker head mounting surface 1 on the central base of the two-axis turntable remains stationary. The simulation model computer transmits the real-time calculated azimuth and pitch information to the two-axis turntable, and the real-time calculated missile-target distance and line-of-sight angle information to the mid-wave infrared target simulator. The turntable drives the infrared target simulator to simulate the relative motion and positional relationship between the aircraft and the target. The specific steps are as follows: Step 1: Simulate the aircraft's heading and pitch motion attitude during flight, as well as the relative motion between the projectile and the target. Step 2: Calculation of control commands for the mid-wave infrared target simulator and simulation of roll angle in the infrared target simulator; Step 3: Final large-angle simulation.

[0018] In one embodiment of the present invention, step one involves simulating the flight attitude of the aircraft in the heading and pitch directions, as well as the relative motion between the missile and the target during flight. The specific calculation method is as follows: using the heading, pitch, and roll angles of the navigation system as inputs, the three angles of the missile system are output through a matrix function transformation between the navigation system and the missile system; then, using the missile-target distances in the three directions (north, south, east, and north) and the three transformed angles as inputs, a multiplication matrix is ​​used to convert them into frame angles in two directions, first heading and then pitch, for control of the two-axis turntable.

[0019] In one embodiment of the present invention, step two, the calculation of control commands for the mid-wave infrared target simulator and the simulation of roll angle in the infrared target simulator, specifically involves the mid-wave infrared target simulator receiving the missile-target distance and line-of-sight angle from the simulation model computer and sending them to the real-time network after calculation, generating various targets and their corresponding regional scenes during flight, and providing simulated targets for the seeker to track. Meanwhile, due to the limitations of the two-axis turntable structure, it is impossible to simulate the rolling motion relationship between the projectile and the target. Therefore, the flight roll angle calculated in real time by the computer in the simulation model is transmitted to the infrared target simulator through a reflective memory network to simulate the relative roll motion and positional relationship between the projectile and the target. The specific calculation method is as follows: using the initial roll angle as the initial value of integration, the angular velocity is integrated over time.

[0020] In one embodiment of the present invention, step three, the final large-angle simulation, specifically includes: Before the target distance is X km, the simulation model computer sends a 0 value to the turntable via a reflective memory network, keeping it stationary. After X km, the actual calculated value is sent to control the turntable movement. A smooth transition function is used to smooth the transition to the actual simulation value within a certain time. Then, terminal guidance simulation is performed according to the actual calculated value. The specific calculation method is as follows: In the initialization module, a time variable T_HW is set and assigned a value of 1000. When the real-time time is less than T_HW, the two-axis turntable control is always 0, and the turntable is stationary. When the target distance is less than X km, the current time value is assigned to the variable T_HW. Within the time period T_HW+X (where X is the transition process time constant), the heading and pitch control values ​​of the two-axis turntable smoothly transition to the actual simulation value through an exponential law.

[0021] In one embodiment of the present invention, the communication method between the simulation model computer and the two-axis turntable and the infrared target simulator is as follows: the two-axis turntable and the mid-wave infrared target simulator communicate with the simulation model computer in real time through the VMIC reflective memory real-time network system.

[0022] In one embodiment of the present invention, the network system consists of an optical fiber data switch, a real-time optical fiber card, and an optical fiber communication cable. The simulator sends real-time calculation data to the two-axis turntable and the infrared target simulator at a set address through the encapsulation function rfm_write_floats, and then reads the actual movement position data of the turntable at a specified address through the rfm_read_floats function.

[0023] In one embodiment of the present invention, based on the relevant dimensions of the two-axis turntable, the seeker head, and the mid-wave infrared target simulator, and taking into account the actual simulation requirements, a tooling design for the two-axis turntable and the mid-wave infrared target simulator is carried out for installation of the seeker head and the mid-wave infrared target simulator during simulation.

[0024] Furthermore, unless otherwise defined, the technical or scientific terms used in this application description shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "upper," "lower," "left," "right," "center," "vertical," "horizontal," "inner," and "outer," etc., used in this application description to indicate relative direction or positional relationship are used only to indicate relative orientation or positional relationship, and do not imply that the device or component must have a specific orientation, or be constructed and operated in a specific orientation. When the absolute position of the described object changes, its relative positional relationship may also change accordingly, and therefore should not be construed as a limitation on this application. The terms "first," "second," "third," and similar terms used in this application description are used only for descriptive purposes to distinguish different components, and should not be construed as indicating or implying relative importance. The terms "a," "one," or "the," etc., used in this application description should not be construed as an absolute limitation on quantity, but should be construed as indicating the existence of at least one. The terms "including," "comprising," etc., used in this application description mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, without excluding other elements or objects.

[0025] Furthermore, it should be noted that, unless otherwise explicitly specified and limited, terms such as “installation,” “connection,” and “linkage” used in the description of this application should be interpreted broadly. For example, a connection 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; or it can be a connection within two components. Those skilled in the art can understand its specific meaning in this application according to the specific circumstances.

[0026] The above description is merely a specific embodiment of the present invention and is not intended to limit the present invention. Within the spirit and principles of the present invention, any person skilled in the art may use the above-disclosed technical content to make changes or modifications to equivalent embodiments and apply them to other fields. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention, as well as any modifications, equivalent substitutions, improvements, etc., should be included within the protection scope of the present invention.

Claims

1. A hardware-in-the-loop simulation test method for a strapdown infrared seeker based on a two-axis turntable, characterized in that, Based on a two-axis turntable, the infrared target simulator is mounted on the pitch frame of the two-axis turntable, and the seeker head is mounted on the seeker head mounting surface on the central base of the two-axis turntable, always in a stationary state; the simulation model computer transmits the real-time calculated azimuth and pitch information to the two-axis turntable, and transmits the real-time calculated missile-target distance and line-of-sight angle information to the mid-wave infrared target simulator. The turntable drives the infrared target simulator to simulate the relative motion and positional relationship between the aircraft and the target.

2. The method as described in claim 1, characterized in that, The specific steps are as follows: Step 1: Simulate the aircraft's heading and pitch motion attitude during flight, as well as the relative motion between the projectile and the target. Step 2: Calculation of control commands for the mid-wave infrared target simulator and simulation of roll angle in the infrared target simulator; Step 3: Final large-angle simulation.

3. The method as described in claim 2, characterized in that, Step 1: Simulate the flight attitude of the aircraft in the heading and pitch directions, as well as the relative motion between the missile and the target during flight. The specific calculation method is as follows: Using the heading, pitch, and roll angles of the navigation system as inputs, the three angles of the missile system are output through the navigation system to missile system matrix function conversion. Then, using the missile-target distances in the three directions of northeast, south, and sky, and the three angles converted above as inputs, the frame angles in the two directions of heading and pitch are converted through a multiplication matrix for two-axis turntable control.

4. The method as described in claim 2, characterized in that, Step two, the control command calculation of the mid-wave infrared target simulator and the roll angle simulation in the infrared target simulator, specifically: the mid-wave infrared target simulator receives the missile-target distance and line-of-sight angle sent to the real-time network by the simulation model computer after calculation, and generates various targets and their area scenes corresponding to the flight process, providing simulated targets for the seeker to track; The flight roll angle calculated in real time by the simulation model computer is transmitted to the infrared target simulator through a reflective memory network to simulate the relative roll motion and positional relationship between the missile and the target. The specific calculation method is as follows: the initial roll angle is used as the initial value of integration, and the angular velocity is integrated over time.

5. The method as described in claim 2, characterized in that, Step 3, final large-angle simulation, specifically: Before the target distance is X km, the simulation model computer sends a 0 value to the turntable via a reflective memory network, keeping it stationary. After X km, the actual calculated value is sent to control the turntable movement. A smooth transition function is used to smooth the transition to the actual simulation value within a certain time. Then, terminal guidance simulation is performed according to the actual calculated value. The specific calculation method is as follows: In the initialization module, a time variable T_HW is set and assigned a value of 1000. When the real-time time is less than T_HW, the two-axis turntable control is always 0, and the turntable is stationary. When the target distance is less than X km, the current time value is assigned to the variable T_HW. Within the time period T_HW+X, the heading and pitch control values ​​of the two-axis turntable smoothly transition to the actual simulation value through an exponential law.

6. The method as described in claim 2, characterized in that, The communication method between the simulation model computer and the two-axis turntable and infrared target simulator is as follows: the two-axis turntable and the mid-wave infrared target simulator communicate with the simulation model computer in real time through the VMIC reflective memory real-time network system.

7. The method as described in claim 6, characterized in that, The network system consists of a fiber optic data switch, a real-time fiber optic card, and fiber optic communication cables. The simulator sends real-time calculation data to the two-axis turntable and infrared target simulator at a set address through the encapsulation function rfm_write_floats, and then reads the actual movement position data of the turntable at a specified address through the rfm_read_floats function.

8. The method as described in claim 7, characterized in that, Based on the relevant dimensions of the two-axis rotary table, the seeker head, and the mid-wave infrared target simulator, and taking into account the actual simulation requirements, the tooling design for the two-axis rotary table and the mid-wave infrared target simulator is carried out for the installation of the seeker head and the mid-wave infrared target simulator during simulation.

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