Inertial Stabilized Platform Servo Loop with Singularity Path Continuous Variable Structure Control Method

Abstract

This invention discloses a method for continuous variable structure control of an inertial stabilization platform servo loop containing singular points, comprising: obtaining the position of the platform in the X-axis. p Axis, Y p Axis and Z p The angular velocity component on the shaft and the measured shaft rotation angle β of the outer frame are obtained. xk The rotation angle β of the middle frame yk The rotation angle β of the inner frame zk Given the values ​​of the parameters of the compliant continuous variable structure and the active region corresponding to the path containing singularities, the angular velocity correction value Δω of the compliant continuous variable structure is calculated; based on β xk β yk β zk And Δω, calculate ω z ω y ω x and ω yk′ ; will ω z ω y ω x and ω yk′ The output, after being fed to the linear controller, acts on the torque motors at each axis end of the inertial stabilization platform, thereby stabilizing the platform body relative to inertial space. This invention overcomes the platform swaying caused by switching between different control signals when using partitioned variable structure control, thus enhancing the stability of the inertial stabilization platform body relative to inertial space and improving the accuracy of navigation calculations.

Description

Technical Field

[0001] This invention belongs to the field of inertial measurement technology, and particularly relates to a method for continuous variable structure control of a servo loop with singular points on an inertial stabilization platform. Background Technology

[0002] Because three-axis inertial platform systems suffer from "frame locking," making it difficult to meet the requirements of large-scale maneuvering of the platform, four-axis inertial platform systems were developed. Compared to three-axis inertial platform systems, four-axis inertial platform systems add an outer frame to the platform body, inner frame, and middle frame. The outer frame is located between the middle frame and the base of the platform.

[0003] In engineering applications, to ensure the platform's stability relative to inertial space, limiting pins are installed on the inner frame axis to restrict the range of the inner frame's angle (generally not exceeding ±45°). When β xk When the angle is ±90°, the inner frame angle will change with the movement of the carrier and cannot be kept at zero. One solution is as follows: "Rotate the outer frame by 90° to bring the inner frame angle back to near zero, and at the same time move the middle frame away from the ±90° position, so that the three-frame four-axis platform can once again meet the working conditions of the traditional servo loop". See the literature "Research on the control strategy of servo frame of four-axis inertial platform, Navigation and Control, No. 4, 2017".

[0004] When this method is used, the angles of the inner frame and the middle frame will be in different ranges. When using zone control, there will be switching between different control signals. However, the switching time will also cause instantaneous shaking of the platform, resulting in the platform body shaking relative to the space.

[0005] So, is it possible to allow the inner frame angle to move freely without restriction? This can be achieved by restricting the middle frame angle β. xk Operating at ±90° also prevents the four rotation axes from being in the same plane. Therefore, there is an urgent need in this field to study a new decoupling method to meet the requirements of all-attitude motion. Summary of the Invention

[0006] The technical problem solved by this invention is to overcome the shortcomings of the prior art and provide a continuous variable structure control method for the servo loop of an inertial stabilization platform with singular points. This method overcomes the swaying of the platform caused by the switching between different control signals when using partitioned variable structure control, thereby enhancing the stability of the inertial stabilization platform relative to the inertial space and improving the accuracy of navigation calculation.

[0007] To address the aforementioned technical problems, this invention discloses a method for continuous variable structure control of a servo loop containing singular points on an inertial stabilization platform, comprising:

[0008] Based on the angular velocity output by the gyroscope mounted on the platform, the position of the platform in the X direction is obtained.p Axis, Y p Axis and Z p angular velocity components on the axis and

[0009] The X coordinates of the outer frame around the body coordinate system of the middle frame were measured. p2 The angle β of the shaft rotation xk The Y-axis of the middle frame around the inner frame's body coordinate system p1 The angle β of the shaft rotation yk The Z-axis of the inner frame around the body coordinate system of the platform p The angle β of the shaft rotation zk ;

[0010] Given the values ​​of the parameters of the compliant continuous variable structure and the active region corresponding to the path containing singularities, the angular velocity correction value Δω of the compliant continuous variable structure is calculated.

[0011] according to β xk β yk β zk And Δω, the Z of the frustum is calculated. p The resultant rotational angular velocity ω of the shaft z Inner frame Y p1 The resultant rotational angular velocity ω of the shaft y , medium framework X p2 The resultant rotational angular velocity ω of the shaft x and outer frame Y p3 The resultant rotational angular velocity ω of the shaft yk′ ;

[0012] ω z ω y ω x and ω yk′ The output is sent to the linear controller and then acts on the torque motors at each axis of the inertial stabilization platform to achieve the stabilization of the platform body relative to the inertial space.

[0013] In the above-mentioned servo loop continuous variable structure control method for inertial stabilization platform with singular point path, the inertial stabilization platform is a four-axis inertial stabilization platform, including: base, outer frame, middle frame, inner frame and platform body;

[0014] The body coordinate systems corresponding to the base, outer frame, middle frame, inner frame, and platform are respectively: base body coordinate system X1Y1Z1, outer frame body coordinate system X... p3 Y p3 Z p3 , Medium frame body coordinate system X p2 Y p2 Z p2 The inner frame body coordinate system Xp1 Y p1 Z p1 and the X coordinate system of the platform body p Y p Z p ;

[0015] Base body coordinate system X1Y1Z1, outer frame body coordinate system X p3 Y p3 Z p3 , Medium frame body coordinate system X p2 Y p2 Z p2 The inner frame body coordinate system X p1 Y p1 Z p1 and the X coordinate system of the platform body p Y p Z p The origins coincide, and: the Z-axis of the platform's body coordinate system coincides with the origin of the platform. p Z-axis and the coordinate system of the inner frame p1 The axes coincide, and the Y-axis of the middle frame body coordinate system is... p2 Y-axis and the coordinate system of the inner frame p1 The axes coincide, and the X coordinate of the outer frame body coordinate system is... p3 The X-axis of the axis and the body coordinate system of the middle frame p2 The axes coincide, the X1 axis of the base body coordinate system and the Y axis of the outer frame body coordinate system. p3 Axis coincidence;

[0016] The base is fixed to the carrier. When the four-axis inertial stabilized platform undergoes internal relative rotation under the drive of the carrier, the base rotates around the Y-axis of the outer frame's body coordinate system. p3 The axis rotates, and the outer frame revolves around the X coordinate system of the middle frame. p2 The axis rotates, and the middle frame rotates around the Y-axis of the inner frame's body coordinate system. p1 The axis rotates, and the inner frame rotates around the Z-axis of the platform's coordinate system. p The shaft rotates.

[0017] In the above-mentioned continuous variable structure control method for servo loops containing singular paths in inertial stabilization platforms, the active regions corresponding to singular path paths include: "three" shaped active regions and "river" shaped active regions.

[0018] In the above-mentioned continuous variable structure control method for the servo loop of the inertial stabilization platform containing singular paths, when the active region corresponding to the singular path is a "three"-shaped active region, the angular velocity correction value Δω of the compliant continuous variable structure is calculated as follows:

[0019] Given the values ​​of the compliant continuous variable structure parameters k, k1, k2, and Δβ, and the "three"-shaped active region β nx ≤βxk ≤β mx ; where k represents the correction coefficient based on the extreme value of the β xk activity area, k1 represents the correction coefficient based on β yk inside the singular circle, k2 represents the correction coefficient based on β yk outside the singular circle, Δβ represents the radius of the singular circle, β nx represents β xk the minimum value of the activity area, β xk represents β xk the maximum value of the activity area; (β nx +β mx ) / 2 = 0°;

[0020] The angular velocity correction value Δω1 of the extreme value of the activity area is calculated through the following formula:

[0021]

[0022] The angular velocity correction value Δω2 of the singular circle is calculated through the following formula:

[0023]

[0024] Among them, the centers of the three singular circles are respectively: (β xk1 , β yk1 ), (β xk2 , β yk2 ), (β xk3 , β yk3 ); β xk1 = 0°, β yk1 = -90°, β xk2 = 0°, β yk2 = 90°, β xk3 = 0°, β yk3 = 270°;

[0025] Then, the angular velocity correction value Δω of the compliant continuous variable structure is: Δω = Δω1 + Δω2.

[0026] In the above control method for the continuous variable structure of the path with singularities in the inertial stable platform servo loop, when the activity area corresponding to the path with singularities is a "Sichuan" - shaped activity area, the angular velocity correction value Δω of the compliant continuous variable structure is calculated through the following method:

[0027] Given the values of the compliant continuous variable structure parameters k, k1, k2, Δβ, and the "Sichuan" - shaped activity area β ny ≤β yk ≤β my ; where k represents the correction coefficient based on β xk the extreme value of the activity area, k1 represents the correction coefficient based on βyk The correction coefficients within the singular circle, k2 represents the values ​​based on β. yk The correction factor outside the singular circle, Δβ, represents the radius of the singular circle, β nx Indicates β xk Minimum value of the active region, β xk Indicates β xk The maximum value of the active area; (β) ny +β my ) / 2 = 90°;

[0028] The angular velocity correction value Δω1 of the extreme value of the active region is calculated using the following formula:

[0029]

[0030] The angular velocity correction value Δω2 of the singular circle can be calculated using the following formula:

[0031]

[0032] The centers of the three singular circles are: (β) xk1 ,β yk1 ), (β) xk2 ,β yk2 ), (β) xk3 ,β yk3 ); β xk1 =0°, β yk1 =90°, β xk2 =180°, β yk2 =90°, β xk3 =-180°, β yk3 =90°;

[0033] Therefore, the angular velocity correction value Δω for the compliant continuous variable structure is: Δω=Δω1+Δω2.

[0034] In the above-mentioned continuous variable structure control method for the servo loop of the inertial stabilization platform containing singular points, ω is calculated using the following formula. z ω y ω x and ω yk′ :

[0035]

[0036] In the aforementioned continuous variable structure control method for the servo loop of the inertial stabilization platform containing singular points, the X-axis of the outer frame around the body coordinate system of the middle frame is measured. p2 The angle β of the shaft rotation xk The Y-axis of the middle frame around the inner frame's body coordinate system p1 The angle β of the shaft rotation ykThe Z-axis of the inner frame around the body coordinate system of the platform p The angle β of the shaft rotation zk ,include:

[0037] X in the outer frame p2 An angle sensor is installed on the shaft to measure β. xk ;

[0038] Y in the inner frame p1 An angle sensor is installed on the shaft to measure β. yk ;

[0039] In the Z of the platform p An angle sensor is installed on the shaft to measure β. zk .

[0040] In the aforementioned continuous variable structure control method for the servo loop of an inertial stabilization platform containing singularity paths, β yk The value range of β is -90 to 270°; zk and β xk The value range is -180 to 180°.

[0041] The present invention has the following advantages:

[0042] (1) This invention discloses a continuous variable structure control method for the servo loop of an inertial stabilization platform with singular point path, which overcomes the influence of the transition process on the stability of the platform during the interval switching process of the partitioned discrete variable structure control, eliminates the dynamic error caused by the frequent shaking caused by the interval switching, and thus improves the accuracy of inertial navigation.

[0043] (2) This invention discloses a continuous variable structure control method for the servo loop of an inertial stabilization platform with singular point path. Compared with the partitioned variable structure control method when the inner frame is limited, it has the characteristic of smaller output energy, which is beneficial to saving control energy.

[0044] (3) This invention discloses a continuous variable structure control method for the servo loop of an inertial stabilization platform with singular point path. Compared with the partitioned variable structure control method when the inner frame is limited, it has the characteristics of small overshoot, no partitioning is required, the control algorithm is simple and easy to implement in engineering. Attached Figure Description

[0045] Figure 1 This is a schematic diagram showing the relationship between the five body coordinate systems in a four-axis inertial stabilization platform according to an embodiment of the present invention;

[0046] Figure 2 This is a flowchart illustrating the steps of a continuous variable structure control method for an inertial stabilization platform servo loop containing singularity paths, as described in an embodiment of the present invention.

[0047] Figure 3It is a schematic diagram of the regions divided according to the inner frame angle and the middle frame angle in the variable structure partition control in the embodiments of the present invention;

[0048] Figure 4 It is a schematic diagram of the change process of the frame angle over time during variable structure partition control in the embodiments of the present invention;

[0049] Figure 5 It is a schematic diagram of the regions where the inner frame and middle frame angles are located during variable structure partition control in the embodiments of the present invention;

[0050] Figure 6 It is a schematic diagram of the change process of the angular velocity of the table body over time during variable structure partition control in the embodiments of the present invention;

[0051] Figure 7 It is a schematic diagram of the change process of the angle of the table body relative to the inertial space over time during variable structure partition control in the embodiments of the present invention;

[0052] Figure 8 It is a schematic diagram of the change process of the frame angle over time during continuous variable structure control based on the "three" - shaped activity region in the embodiments of the present invention;

[0053] Figure 9 It is a schematic diagram of the regions where the inner frame and middle frame angles are located during continuous variable structure control based on the "three" - shaped activity region in the embodiments of the present invention;

[0054] Figure 10 It is a schematic diagram of the change process of the angular velocity of the table body over time during continuous variable structure control based on the "three" - shaped activity region in the embodiments of the present invention;

[0055] Figure 11 It is a schematic diagram of the change process of the angle of the table body relative to the inertial space over time during continuous variable structure control based on the "three" - shaped activity region in the embodiments of the present invention;

[0056] Figure 12 It is a schematic diagram of the change process of the frame angle over time during continuous variable structure control based on the "chuan" - shaped activity region in the embodiments of the present invention;

[0057] Figure 13 It is a schematic diagram of the regions where the inner frame and middle frame angles are located during continuous variable structure control based on the "chuan" - shaped activity region in the embodiments of the present invention;

[0058] Figure 14 It is a schematic diagram of the change process of the angular velocity of th e table body over time during continuous variable structure control based on the "chuan" - shaped activity region in the embodiments of the present invention;

[0059] Figure 15It is a schematic diagram of the change process of the angle of the table body relative to the inertial space over time during continuous variable structure control based on the "Sichuan" - shaped active area in the embodiment of the present invention. Detailed implementation manners

[0060] To make the objectives, technical solutions, and advantages of the present invention clearer, the following will further describe in detail the disclosed embodiments of the present invention with reference to the accompanying drawings.

[0061] The present invention discloses a method for continuous variable structure control of an inertial stabilization platform servo loop with singular points, which is implemented based on a four - axis inertial stabilization platform. The four - axis inertial stabilization platform includes: a base, an outer frame, a middle frame, an inner frame, and a table body. Among them, the respective body coordinate systems corresponding to the base, the outer frame, the middle frame, the inner frame, and the table body are: the base body coordinate system X1Y1Z1, the outer frame body coordinate system X p3 Y p3 Z p3 , the middle frame body coordinate system X p2 Y p2 Z p2 , the inner frame body coordinate system X p1 Y p1 Z p1 and the table body coordinate system X [[ID=We]] p Y p Z p . As Figure 1 shown, the origins of the base body coordinate system X1Y1Z1, the outer frame body coordinate system X p3 Y p3 Z p3 , the middle frame body coordinate system X p2 Y p2 Z p2 , the inner frame body coordinate system X p1 Y p1 Z p1 and the table body coordinate system X p Y p Z p coincide, and: the Z p axis of the table body coordinate system coincides with the Z p1 axis of the inner frame body coordinate system, the Y p2 axis of the middle frame body coordinate system coincides with the Y p1 axis of the inner frame body coordinate system, the X p3 axis of the outer frame body coordinate system coincides with the X p2 axis of the middle frame body coordinate system, and the X1 axis of the base body coordinate system coincides with the Y p3 axis of the outer frame body coordinate system. The base is fixedly connected to the carrier. When the four - axis inertial stabilization platform rotates internally relative to each other under the drive of the carrier, the base rotates around the Y p3The axis rotates, and the outer frame revolves around the X coordinate system of the middle frame. p2 The axis rotates, and the middle frame rotates around the Y-axis of the inner frame's body coordinate system. p1 The axis rotates, and the inner frame rotates around the Z-axis of the platform's coordinate system. p The shaft rotates.

[0062] like Figure 2 As shown, in this embodiment, the inertial stabilization platform servo loop includes a continuous variable structure control method for singular point paths, comprising:

[0063] Step 1: Based on the angular velocity output by the gyroscope mounted on the platform, obtain the angular velocity of the platform in the X direction. p Axis, Y p Axis and Z p angular velocity components on the axis and

[0064] Step 2: Measure the X coordinate of the outer frame around the coordinate system of the middle frame. p2 The angle β of the shaft rotation xk The Y-axis of the middle frame around the inner frame's body coordinate system p1 The angle β of the shaft rotation yk The Z-axis of the inner frame around the body coordinate system of the platform p The angle β of the shaft rotation zk .

[0065] In this embodiment, the X-axis of the outer frame can be... p2 An angle sensor is installed on the shaft to measure β. xk ; in the inner frame Y p1 An angle sensor is installed on the shaft to measure β. yk ; in the Z of the platform p An angle sensor is installed on the shaft to measure β. zk Among them, β yk The value range of β is -90 to 270°; zk and β xk The value range is -180 to 180°.

[0066] Step 3: Given the values ​​of the parameters of the compliant continuous variable structure and the active region corresponding to the path containing the singularity, calculate the angular velocity correction value Δω of the compliant continuous variable structure.

[0067] In this embodiment, the activity regions corresponding to singularity paths include, but are not limited to, "three"-shaped activity regions and "river"-shaped activity regions.

[0068] Preferably, when the active region corresponding to the path containing the singularity is a "three"-shaped active region, the angular velocity correction value Δω of the compliant continuous variable structure is calculated as follows:

[0069] Given the values of the compliant continuous variable structure parameters k, k1, k2, and Δβ, and the "three" - shaped active region β nx ≤β xk ≤β mx . Among them, k represents the correction coefficient based on the extreme value of the β xk active region, k1 represents the correction coefficient within the singular circle based on β yk , k2 represents the correction coefficient outside the singular circle based on β yk , Δβ represents the radius of the singular circle, and β nx represents the minimum value of the β<00001​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​xk The correction coefficient for the extreme values ​​of the active region, k1 represents the value based on β. yk The correction coefficients within the singular circle, k2 represents the values ​​based on β. yk The correction factor outside the singular circle, Δβ, represents the radius of the singular circle, β nx Indicates β xk Minimum value of the active region, β xk Indicates β xk The maximum value of the active area; (β) ny +β my ) / 2 = 90°.

[0078] The angular velocity correction value Δω1 of the extreme value of the active region is calculated using the following formula:

[0079]

[0080] The angular velocity correction value Δω2 of the singular circle can be calculated using the following formula:

[0081]

[0082] The centers of the three singular circles are: (β) xk1 ,β yk1 ), (β) xk2 ,β yk2 ), (β) xk3 ,β yk3 ); β xk1 =0°, β yk1 =90°, β xk2 =180°, β yk2 =90°, β xk3 =-180°, β yk3 =90°.

[0083] Therefore, the angular velocity correction value Δω for the compliant continuous variable structure is: Δω=Δω1+Δω2.

[0084] Step 4, based on ω xp ω yp ω zp β xk β yk β zk And Δω, the Z of the frustum is calculated. p The resultant rotational angular velocity ω of the shaft z Inner frame Y p1 The resultant rotational angular velocity ω of the shaft y , medium framework X p2 The resultant rotational angular velocity ω of the shaft x and outer frame Y p3 The resultant rotational angular velocity ω of the shaft yk′ .

[0085] In this embodiment, ω can be calculated using the following formula. z ω y ω x and ω yk′ :

[0086]

[0087] Step 5, ω z ω y ω x and ω yk′ The output is sent to the linear controller and then acts on the torque motors at each axis of the inertial stabilization platform to achieve the stabilization of the platform body relative to the inertial space.

[0088] To further illustrate the high precision of the decoupler of the present invention, several examples are provided below.

[0089] Reference: "Research on Control Strategy of Four-Axis Inertial Platform Follower Frame, Navigation and Control, 2017, No. 4", assuming the inner frame limit value β. n =45°, β m =135°, the area controlled by the locking partition discrete variable structure when the inner frame angle is limited is as follows: Figure 3 As shown. The main problem with this method is that the motion trajectory cannot cross from region 32 to region 31; it can only move forward by constantly switching along the boundary, causing the platform to shake.

[0090] Let β yk′ β xk β yk β zk The initial values ​​are 0°, 90°, 0°, and 0° respectively. When using variable structure zoning control, the initial position is in region 32. Let the platform base angular velocity...

[0091] The time-varying process of the frame angle in the locking-type discrete variable structure partition control when using inner frame angle limiting is as follows: Figure 4 As shown, the areas where the inner and outer frames are located are as follows: Figure 5 As shown, the change of the angular velocity of the platform with time is as follows: Figure 6 As shown, the angle θ between the platform and the inertial space x θ y θ z The process of change over time is as follows Figure 7 As shown. Throughout the entire operation, the inner frame angle never exceeded the limit of 45°, but during the switching process, both the platform's angular velocity and angle exhibited high-frequency vibrations. Specifically, the platform's angular velocity... The maximum value is approximately -291° / s, ω ypAt the switching moment, the maximum value is approximately -167° / s, and the angle θ of the table body relative to the inertial space x At the moment of closing at zero, the maximum value can reach 1.983°, θ y At the switching moment, the maximum value is approximately 0.96°.

[0092] Example 1

[0093] To overcome the shaking problem, a continuous variable structure control method with a "three" - shaped path is adopted for control. Let β nx =-135°, β mx =135°, k = 4×10 -6 、k1 = 6×10 -6 、k2 = 3×10 -6 、Δβ = 30°, β yk′ 、β xk 、β yk 、β zk The initial values of are 0°, 90°, 0°, 0° respectively. The variation process of the frame angle with time is as Figure 8 shown. The regions where the inner - frame and middle - frame angles are located are as Figure 9 shown. The variation process of the table - body angular velocity with time is as Figure 10 shown. The angles θ x 、θ y 、θ z of the table body relative to the inertial space vary with time as Figure 11 shown. During the operation, the maximum value of the table - body angular velocity is 1.5×10 -3 ° / s, the maximum value of is 3.0×10 -4 ° / s. The maximum value of the angle θ x of the table body relative to the inertial space is -1.58×10 -3 °, θ y the maximum value of is -2.1×10 -3 °. It can be seen that during the whole operation process, the angular motion of the table body relative to the inertial space is relatively stable.

[0094] By comparing the partitioned discrete variable - structure control with the "three" - shaped path continuous variable - structure control method of the present invention, it can be seen that the overshoot of the angle and angular velocity of the table body relative to the inertial space is significantly reduced, and there is no continuous shaking process. The method of the present invention has higher precision.

[0095] Example 2

[0096] To overcome the shaking problem, a continuous variable structure control method with a "chuan" - shaped path is adopted for control. Let β ny =-45°, β my =225°, k = 4×10-6 , k1 = 6×10 -5 , k2 = 3×10 -6 , Δβ = 30°, β yk′ , β xk , β yk , β zk The initial values of are 0°, 90°, 0°, 0° respectively. The variation process of the frame angle with time is as shown in Figure 12 , and the regions where the angles of the inner frame and the middle frame are located are as shown in Figure 13 . The variation process of the angular velocity of the table body with time is as shown in Figure 14 . The angle θ of the table body relative to the inertial space x , θ y , θ z The variation process with time is as shown in Figure 15 . During the operation, the maximum angular velocity of the table body is 1.4° / s, the maximum is 1.66° / s. The angle θ of the table body relative to the inertial space x the maximum is -0.1165°, θ y the maximum is 0.16°. It can be seen that during the entire operation process, the angular motion of the table body relative to the inertial space is relatively stable.

[0097] By comparing the partitioned discrete variable structure control with the "Sichuan" - shaped path continuous variable structure control method of the present invention, it can be seen that the overshoot of the angle and angular velocity of the table body relative to the inertial space is significantly reduced, and there is no continuous shaking process. The method of the present invention has higher precision.

[0098] Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solution of the present invention using the disclosed methods and technical contents without departing from the spirit and scope of the present invention. Therefore, any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention all fall within the protection scope of the technical solution of the present invention.

[0099] The content not detailedly described in the specification of the present invention belongs to the well - known technology of those skilled in the art.

Claims

1. A method for continuous variable structure control of a servo loop containing singular points on an inertial stabilization platform, characterized in that, include: Based on the angular velocity output by the gyroscope mounted on the platform, the position of the platform in the X direction is obtained. p Axis, Y p Axis and Z p angular velocity components on the axis , and ; The X coordinates of the outer frame around the body coordinate system of the middle frame were measured. p2 Angle of rotation of the shaft The Y-axis of the middle frame around the inner frame's body coordinate system p1 Angle of rotation of the shaft The Z-axis of the inner frame around the body coordinate system of the platform p Angle of rotation of the shaft ; Given the values ​​of the parameters of the compliant continuous variable structure and the active region corresponding to the path containing singularities, the angular velocity correction value of the compliant continuous variable structure is calculated. ; according to , , , , , and Δ ω The Z-shape of the platform is calculated. p The resultant rotational angular velocity of the shaft Inner frame Y p1 The resultant rotational angular velocity of the shaft , medium framework X p2 The resultant rotational angular velocity of the shaft and outer frame Y p3 The resultant rotational angular velocity of the shaft ; Will , , and The output is sent to the linear controller and then acts on the torque motors at each axis of the inertial stabilization platform to achieve the stabilization of the platform body relative to the inertial space. When the activity region corresponding to the path containing singularities is a "three"-shaped activity region, it is calculated as follows: : Given compliant continuous variable structure parameters , , Δ β The value, and the "three"-shaped activity area β nx β xk β mx ;in, Indicates based on β xk Correction coefficient for extreme values ​​in the active region. Indicates based on β xk Correction coefficients within the singular circle, Indicates based on β xk Correction factor outside the singular circle, Δ β Represents the radius of the singular circle. β nx express β xk Minimum value of the activity area β mx express β xk The maximum value of the active area; β nx + β mx ) / 2=0 ; The angular velocity correction value of the extreme value of the active region can be calculated using the following formula. : The angular velocity correction value of the extreme value of the active region can be calculated using the following formula. : The centers of the three strange circles are respectively: ( β xk1 , β yk1 ), ( β xk2 , β yk2 ), ( β xk3 , β yk3 ); β xk1 =0 , β yk1 =-90 , β xk2 =0 , β yk2 =90 , β xk3 =0 , β yk3 =270 ; but, for: ; When the active area corresponding to the path containing singularities is a "Sichuan"-shaped active area, it is calculated by the following method : Given compliant continuous variable structure parameters , , , Δ β values, and the "Sichuan"-shaped active area β ny β yk β my ; where represents the correction coefficient based on β yk the extreme value of the active area, represents the correction coefficient based on β yk inside the singular circle, represents the correction coefficient based on β yk outside the singular circle, β ny represents β yk the minimum value of the active area, β my represents β yk the maximum value of the active area; ( β ny + β my ) / 2 = 90 ; The angular velocity correction value of the extreme value of the active region can be calculated using the following formula. : The angular velocity correction value of the singular circle can be calculated using the following formula. : The centers of the three strange circles are respectively: ( β xk1 , β yk1 ), ( β xk2 , β yk2 ), ( β xk3 , β yk3 ); β xk1 =0 , β yk1 =90 , β xk2 =180 , β yk2 =90 , β xk3 =-180 , β yk3 =90 ; but, for: .

2. The method for continuous variable structure control of the servo loop containing singular points on an inertial stabilization platform according to claim 1, characterized in that, The inertial stabilization platform is a four-axis inertial stabilization platform, comprising: a base, an outer frame, a middle frame, an inner frame, and a platform body; The body coordinate systems corresponding to the base, outer frame, middle frame, inner frame, and platform are respectively: base body coordinate system X1Y1Z1, outer frame body coordinate system X... p3 Y p3 Z p3 , Medium frame body coordinate system X p2 Y p2 Z p2 The inner frame body coordinate system X p1 Y p1 Z p1 and the X coordinate system of the platform body p Y p Z p ; Base body coordinate system X1Y1Z1, outer frame body coordinate system X p3 Y p3 Z p3 , Medium frame body coordinate system X p2 Y p2 Z p2 The inner frame body coordinate system X p1 Y p1 Z p1 and the X coordinate system of the platform body p Y p Z p The origins coincide, and: the Z-axis of the platform's body coordinate system coincides with the origin of the platform. p Z-axis and the coordinate system of the inner frame p1 The axes coincide, and the Y-axis of the middle frame body coordinate system is... p2 Y-axis and the coordinate system of the inner frame p1 The axes coincide, and the X coordinate of the outer frame body coordinate system is... p3 The X-axis of the axis and the body coordinate system of the middle frame p2 The axes coincide, the X1 axis of the base body coordinate system and the Y axis of the outer frame body coordinate system. p3 Axis coincidence; The base is fixed to the carrier. When the four-axis inertial stabilized platform undergoes internal relative rotation under the drive of the carrier, the base rotates around the Y-axis of the outer frame's body coordinate system. p3 The axis rotates, and the outer frame revolves around the X coordinate system of the middle frame. p2 The axis rotates, and the middle frame revolves around the Y-axis of the inner frame's body coordinate system. p1 The axis rotates, and the inner frame rotates around the Z-axis of the platform's coordinate system. p The shaft rotates.

3. The method for continuous variable structure control of the servo loop containing singular points on an inertial stabilization platform according to claim 1, characterized in that, Calculated using the following formula , , and : 。 4. The method for continuous variable structure control of the servo loop containing singular points on an inertial stabilization platform according to claim 1, characterized in that, The X coordinates of the outer frame around the body coordinate system of the middle frame were measured. p2 Angle of rotation of the shaft The Y-axis of the middle frame around the inner frame's body coordinate system p1 Angle of rotation of the shaft The Z-axis of the inner frame around the body coordinate system of the platform p Angle of rotation of the shaft ,include: X in the outer frame p2 An angle sensor is installed on the shaft to measure the angle. ; Y in the inner frame p1 An angle sensor is installed on the shaft to measure the angle. ; In the Z of the platform p An angle sensor is installed on the shaft to measure the angle. .

5. The method for continuous variable structure control of the servo loop containing singular points on an inertial stabilization platform according to claim 1, characterized in that, β yk The value range is -90 to 270°; β zk and β xk The value range is -180 to 180°.

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