Multi-tank spacecraft filling process quality characteristic control method

Abstract

The invention provides a multi-tank spacecraft filling process quality characteristic control method, and the method comprises the steps: setting a control point for quality characteristic control according to the filling demands of a spacecraft; in the spacecraft filling process, when a control point is reached, whether the quality characteristic meets the requirement or not is judged, if the requirement is met, filling is continued, and judgment is continued at the next control point until filling is completed; and if the quality characteristics do not meet the requirements, the filling amount of the propellants in the storage tanks at different positions of the same propellant is adjusted, and the mass center of the spacecraft is adjusted under the condition that the balance weight is not increased.

Description

Technical Field

[0001] The method of the invention can be applied to the quality characteristic control work of the filling process of multi-tank spacecraft with higher quality characteristic requirements. Background Art

[0002] As spacecraft missions become more and more complex, the requirements for the control accuracy of spacecraft mass characteristics are also getting higher and higher. Spacecraft propellant generally accounts for a high proportion of the spacecraft mass. Due to uncertain factors such as the processing error and assembly error of the tank that carries the propellant, there is a certain uncertainty in the mass characteristics of the spacecraft propellant, which may lead to a large deviation between the final mass characteristics of the spacecraft after filling and the required value. Especially for multi-cabin spacecraft, the mass characteristics of the propellant after filling are coupled with the cabin docking accuracy. If special methods are not taken to control it, the final mass characteristics of the multi-cabin spacecraft after filling may not meet the mission requirements. Summary of the invention

[0003] The technical problem solved by the present invention is: controlling the mass characteristics of the propellant during the filling process, so that the mass characteristics of the spacecraft after filling can meet the requirements without implementing counterweight.

[0004] The technical problem further solved by the present invention is that for a multi-compartment spacecraft, more accurate propellant mass characteristics can be obtained.

[0005] The technical solution of the present invention is: a method for controlling the quality characteristics of a single-cabin multi-tank spacecraft filling process, comprising:

[0006] Set control points for mass characteristic control according to the spacecraft refueling requirements;

[0007] During the process of refueling the spacecraft, when it reaches the control point, it is determined whether the mass characteristics meet the requirements. If so, refueling will continue, and then continue to determine at the next control point until the refueling is completed. If the mass characteristics do not meet the requirements, the amount of propellant in the tanks at different positions of the same propellant will be adjusted to adjust the center of mass of the spacecraft without increasing the counterweight.

[0008] Preferably, the refilling amount of the same propellant in the tanks at different positions is adjusted to adjust the center of mass of the spacecraft without adding counterweight, and the refilling amount of each tank that minimizes the deviation of the center of mass of the spacecraft is obtained by the following set of equations:

[0009]

[0010] Among them, tank i refers to the tank that needs to be filled with the same propellant, its center of mass position coordinates are (Xi, Yi, Zi), the test mass of the spacecraft before balancing is M, the test center of mass is (X, Y, Z), the target center of mass for balancing is (X0, Y0, Z0), the propellant mass required to adjust the center of mass is M', and the refilling amount of tank i is mi.

[0011] Preferably, the control points include two, namely the middle value of the propellant and -10kg.

[0012] A method for controlling quality characteristics of a multi-cabin and multi-tank spacecraft filling process, comprising:

[0013] Determine whether there is a compartment in the multi-cabin that is filled separately. If it is filled separately, the compartment adopts the single-cabin multi-tank spacecraft filling process quality characteristic control method to complete the filling process quality characteristic control, and the compartment after the separate filling is used as a fixed quality unit to participate in the multi-cabin quality characteristic test;

[0014] Measure all cabin sections that do not need to be filled separately, obtain the relationship between the mechanical coordinate system of each cabin section and the measurement coordinate system of the quality test platform, determine the direction transformation matrix and origin transformation matrix of each cabin section; and then convert them into the current center of mass of each cabin section;

[0015] The quality characteristic control method of the filling process of a single-cabin multi-tank spacecraft is used to complete the quality characteristic control of the filling process for each cabin section.

[0016] Preferably, the centroid conversion formula of the current propellant filling in each compartment is:

[0017] (X' j Y j 'Z' j )=(XT j YT j ZT j )+(X j Y j Z j )×A j

[0018] Among them, (XT j YT j ZT j ) is the origin transformation matrix of compartment j, A j is the direction transformation matrix of compartment j, (X j Y j Z j ) The center of mass of the propellant filled in the cabin before conversion, (X' j Y j 'Z' j ) After conversion, the propellant filling center of compartment j is

[0019] Preferably, the mass characteristic parameter (XYZ) of compartment j after filling is calculated based on the propellant center of mass of compartment j in combination with the previous test result of the center of mass of compartment j in dry weight state, and then the mass characteristic is judged to determine whether the deviation between (XY Z) and the target center of mass (X0Y0Z0) is within the allowable range. If so, continue to fill; if not, adjust the filling amount of the propellant in the tanks at different positions of the same propellant to achieve the balance by adjusting the center of mass of the spacecraft without adding counterweight.

[0020] Preferably, the quality characteristic control processes of all compartments that do not require separate filling are performed alternately.

[0021] Preferably, all the compartment quality characteristic control processes that do not require separate filling are executed serially.

[0022] The beneficial effects of the present invention compared with the prior art are:

[0023] By means of the method of the present invention, the quality characteristics of the propellant can be effectively controlled during the filling process, so that the quality characteristics of a multi-tank spacecraft with high quality characteristics requirements can meet the requirements after filling.

[0024] Through the method of the present invention, different methods can be selected according to the characteristics of the spacecraft to control the quality characteristics of the filling process of multi-tank spacecraft with high quality characteristics, and the obtained spacecraft quality characteristics are more accurate, and no additional weight is required to ensure that the spacecraft quality characteristics meet the requirements. At the same time, for multi-cabin spacecraft, more accurate propellant quality characteristics can be obtained.

[0025] The setting of the control point of the present invention can meet the mixing ratio deviation of the injected propellant, and ensure that the deviation of the injected amount of propellant used to adjust the center of mass meets the requirement. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Flow chart of the method of the present invention;

[0027] Figure 2 This is a schematic diagram of a single cabin section;

[0028] Figure 3 This is a schematic diagram of multiple compartments. DETAILED DESCRIPTION

[0029] The following is combined with Figure 1 The present invention is further illustrated by the following examples.

[0030] The method of the present invention can analyze the input information such as the cabin combination form, filling scheme, tank status, etc. of the spacecraft, determine the cabin combination state of the spacecraft during filling, and select different routes to control the propellant quality characteristics according to different combination states. Figure 2The multi-tank combined filling status is shown in the attached Figure 3 shown.

[0031] 1) Single-cabin spacecraft or multi-cabin spacecraft with single-cabin refueling can directly refuel and carry out propellant mass characteristic control.

[0032] (1) The control point is set according to the needs of each model. Generally, two control points are set, namely the middle value of the propellant and -10kg;

[0033] (2) After reaching the control point, if the mass characteristics do not meet the requirements, the propellant filling amount of the same propellant tanks at different positions is adjusted to adjust the center of mass of the spacecraft without adding counterweight;

[0034] After the quality characteristic test of the single-tank filling process is completed, the quality characteristic is judged to test whether the deviation between the center of mass (X, Y, Z) and the target center of mass (X0Y0Z0) is within the allowable range (ΔX0ΔY0ΔZ0). If yes, continue filling; if not, perform balancing according to the following method.

[0035] The single tank refueling process is generally to add fuel first, and then add oxidizer after the fuel is balanced according to the above process.

[0036] The specific treatment methods for the same type of propellant are as follows.

[0037] The position of tank i (Xi, Yi, Zi), the current spacecraft mass M, the center of mass (X, Y, Z), the target center of mass (X0, Y0, Z0), the mass of propellant required to adjust the center of mass M', and the refilling amount of tank i mi, then:

[0038]

[0039] Through the above equation, the refilling amount of each tank that minimizes the deviation of the spacecraft's center of mass can be obtained.

[0040] 2) For multi-cabin spacecraft with integral filling or multi-cabin spacecraft with some compartments filled separately, the cabin assembly is completed (generally refers to the cabins being assembled according to the assembly relationship, such as the attached Figure 3 1). After that, a high-precision measurement method of a theodolite or a laser tracker is used to obtain the relationship between the mechanical coordinate system of each compartment and the measurement coordinate system of the quality measurement platform. The quality measurement data is corrected through the obtained relationship matrix, and then the propellant mass characteristics of each compartment are controlled using the technical route 1).

[0041] Attach Figure 3 For example, cabin sections 1-4 are assembled according to the relationship shown in the figure and then docked with the quality inspection platform, among which cabin section 4 is a separate filling cabin section. Generally, the filling operation is not accessible in the combined state or the cabin sections with relatively independent functions are filled separately.

[0042] The coordinate system involved in the method is defined as follows:

[0043] Cabin mechanical coordinate system: It is generally defined on the docking bottom surface of the cabin, with the center of the docking surface as the coordinate origin. The vertical bottom surface is generally defined as the X-axis, and the Y and Z axes are generally defined as axes parallel to the docking bottom surface and perpendicular to each other.

[0044] The measurement coordinate system of the quality test platform is generally defined at the interface between the quality test platform and the object to be measured. The center of the interface is the coordinate origin, and the X, Y, and Z axes are generally defined to be consistent with the direction of the object to be measured. The quality test platform is generally connected to the object to be measured through repeatable positioning devices such as positioning pins, so it is generally consistent with the mechanical coordinate system of the cabin to which it is connected.

[0045] The specific method for controlling the mass characteristics of multi-compartment propellants is as follows.

[0046] (1) The transformation matrix of the compartment j direction obtained by high-precision measurement is: (Each parameter in the matrix is ​​the spatial rotation angle parameter between the mechanical coordinate system of cabin j and the coordinate system of the quality test platform)

[0047] (2) The origin transformation matrix of compartment j obtained by high-precision measurement is (XT j YT j ZT j ), i.e., the position parameters of the origin of the mechanical coordinate system of cabin j and the origin of the coordinate system of the quality testing platform;

[0048] (3) Propellant mass center of compartment i before conversion (X j Y j Z j ), then the center of mass of the propellant in compartment j after conversion is (X' j Y j 'Z' j )=(XT j YT j ZT j )+(X j Y j Z j )×A j ;

[0049] (4) According to the dry mass center of mass of compartment j (referring to the mass characteristic test result of the compartment before filling with propellant, which will be the dry mass center of mass parameter relative to the mechanical coordinate system of the compartment), the mass characteristic parameter (XYZ) of the superimposed propellant is calculated by the mass characteristic calculation formula of the theoretical mechanics combination, and the mass characteristic parameter (XYZ) of compartment j after filling is obtained. It is judged whether the deviation between (XYZ) and the target mass center (X0Y0Z0) is within the allowable range. If so, continue to fill, otherwise adopt the 1) technical route to carry out quality characteristic control. After the filling of compartment j is completed, more accurate propellant mass characteristics can be obtained.

[0050] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, 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 shall fall within the protection scope of the technical solution of the present invention.

Claims

1. A method for controlling the quality characteristics of a single-cabin multi-tank spacecraft refueling process, characterized in that include: Set control points for mass characteristic control according to the spacecraft refueling requirements; During the process of refueling the spacecraft, when it reaches the control point, it is determined whether the mass characteristics meet the requirements. If so, refueling will continue, and then continue to determine at the next control point until the refueling is completed. If the mass characteristics do not meet the requirements, the amount of propellant in the tanks at different positions of the same propellant will be adjusted to adjust the center of mass of the spacecraft without increasing the counterweight.

2. The method according to claim 1, characterized in that: By adjusting the filling amount of the same propellant in the tanks at different positions, the center of mass of the spacecraft can be adjusted without adding counterweight. The refilling amount of each tank that minimizes the deviation of the center of mass of the spacecraft is obtained through the following equations: Among them, tank i refers to the tank that needs to be filled with the same propellant, its center of mass position coordinates are (Xi, Yi, Zi), the test mass of the spacecraft before balancing is M, the test center of mass is (X, Y, Z), the target center of mass for balancing is (X0, Y0, Z0), the propellant mass required to adjust the center of mass is M', and the refilling amount of tank i is mi.

3. The method according to claim 1, characterized in that: The control points include two, namely the middle value of the propellant and -10kg.

4. A method for controlling the quality characteristics of a multi-cabin and multi-tank spacecraft refueling process, characterized in that include: Determine whether there is a compartment in the multiple compartments that is individually filled. If it is individually filled, the compartment adopts the single-cabin multi-tank spacecraft filling process quality characteristic control method described in any one of claims 1-3 to complete the filling process quality characteristic control, and the compartment after the individual filling participates in the multi-cabin quality characteristic test as a fixed quality unit; Measure all cabin sections that do not need to be filled separately, obtain the relationship between the mechanical coordinate system of each cabin section and the measurement coordinate system of the quality test platform, determine the direction transformation matrix and origin transformation matrix of each cabin section; and then convert them into the current center of mass of each cabin section; The quality characteristic control method of the filling process of a single-cabin multi-tank spacecraft as described in any one of claims 1 to 3 is used to complete the quality characteristic control of the filling process for each cabin section.

5. The method according to claim 4, characterized in that: The formula for converting the center of mass of the current propellant filling in each compartment is: (X' j Y j 'Z' j )=(XT j YT j ZT j )+(X j Y j Z j )×A j Among them, (XT j YT j ZT j ) is the origin transformation matrix of compartment j, A j is the direction transformation matrix of compartment j, (X j Y j Z j ) The center of mass of the propellant filled in the cabin before conversion, (X' j Y j 'Z' j ) After conversion, the propellant filling center of the compartment j is 6. The method according to claim 4, characterized in that: According to the propellant center of mass of compartment j and the test results of the center of mass of compartment j in dry weight state, the mass characteristic parameters (XY Z) of compartment j after filling are calculated. Then the mass characteristic is judged to determine whether the deviation between (XYZ) and the target center of mass (X0 Y0 Z0) is within the allowable range. If yes, continue to fill. If not, adjust the filling amount of the same propellant in the tanks at different positions to achieve the balance of the spacecraft without increasing the counterweight.

7. The method according to claim 4, characterized in that: The quality characteristic control process of all compartments that do not require separate filling is carried out alternately.

8. The method according to claim 4, characterized in that: All the quality characteristic control processes of the compartments that do not require separate filling are executed serially.

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