Optimization method for initial position of asteroid hovering and attaching probe trajectory

Abstract

The asteroid hovering / attaching probe trajectory initial position optimization method disclosed by the application belongs to the technical field of spacecraft guidance and control. The implementation method of the application is as follows: a minimum hovering fuel consumption evaluation model is established through a dynamic equation of a hovering process, and the minimum hovering fuel consumption of a given hovering point is obtained by optimization taking the minimum hovering fuel consumption as an optimization index. According to a dynamic model of a probe attaching process, a sequence convex optimization method is used to optimize an optimal attaching fuel consumption trajectory, the minimum fuel consumption of the attaching process under the condition of a given hovering point is obtained, and a hovering point attaching trajectory minimum fuel consumption evaluation model is built. On the basis of the hovering fuel consumption evaluation model and the attaching trajectory minimum fuel consumption evaluation model, a hovering point optimization problem model considering attachment is established, the hovering point position and the attachment time parameter are taken as optimization variables, the total fuel consumption of the hovering and attaching processes is taken as a performance index, and the interior point method is used to optimize and solve the hovering position required for the minimum total fuel consumption of the hovering process and the attaching process.

Description

Technical Field

[0001] This invention relates to a spacecraft trajectory optimization method, and more particularly to a method for optimizing the initial position of an asteroid hovering / attachment probe trajectory, belonging to the field of spacecraft guidance and control technology. Background Technology

[0002] Asteroid exploration has become a research hotspot in the field of deep space exploration both domestically and internationally, and is of great significance for exploring the evolution of the solar system and the origin of life, defending against near-Earth asteroid impacts, and promoting the development of space technology. With the continuous deepening of research related to asteroid exploration missions, surface-mounting exploration has become the main exploration method. Asteroid hovering is one of the commonly used methods for close-range asteroid exploration, and it will fully prepare for subsequent surface-mounting missions. Asteroid probes have limited fuel and complex gravitational field environments; therefore, choosing a suitable hovering location to reduce fuel consumption during the exploration process is of great importance for reducing exploration costs and carrying out subsequent scientific research missions.

[0003] Currently, research on asteroid hovering exploration mainly focuses on selecting the asteroid's equilibrium point and designing hovering control methods, without considering the subsequent attachment process. The fuel consumption requirements for hovering and attachment vary depending on the hovering point's location. When considering the attachment process, the traditional equilibrium point may not be the optimal hovering point for fuel consumption. Given a target attachment point and satisfying multiple constraints, the initial hovering position that minimizes the total fuel consumption required for both hovering and attachment can be called the optimal hovering point. To solve for the optimal hovering point of an asteroid probe, it is necessary to develop an initial position optimization method for asteroid hovering / attachment exploration trajectories. Summary of the Invention

[0004] Addressing the challenges of asteroid hovering and surface attachment exploration, this invention aims to provide a method for optimizing the initial position of asteroid hovering / attachment trajectories, considering the need to reduce the total fuel consumption required for both hovering and attachment processes while satisfying multiple constraints such as thrust amplitude, initial and final velocities, and positional requirements. Based on the dynamic model of the hovering process, a minimum hovering fuel consumption evaluation model is established for the hovering point, and this model is used to optimize the minimum hovering fuel consumption at a given hovering point. Similarly, based on the dynamic model of the attachment process, a minimum attachment trajectory fuel consumption evaluation model is established for the attachment point, and the fuel consumption trajectory is optimized using a sequential convex optimization method to obtain the minimum fuel consumption for the attachment process. Based on the hovering fuel consumption evaluation model and the minimum attachment trajectory fuel consumption evaluation model, using hovering point position parameters and attachment time parameters as optimization variables, and the total fuel consumption of the hovering and attachment processes as the performance index, a model for optimizing the initial position of asteroid hovering and attachment trajectories is established. The interior point method is then used to optimize and solve for the hovering position that minimizes the total fuel consumption required for both hovering and attachment processes.

[0005] The objective of this invention is achieved through the following technical solution.

[0006] This invention discloses a method for optimizing the initial position of an asteroid hovering / attachment trajectory. It establishes a minimum hovering fuel consumption evaluation model based on the dynamic equations of the hovering process, using the minimum hovering fuel consumption as the optimization index to obtain the minimum hovering fuel consumption at a given hovering point. Based on the dynamic model of the probe's attachment process, the optimal trajectory for attachment fuel consumption is optimized using the sequential convex optimization method to obtain the minimum fuel consumption of the attachment process under a given hovering point condition, thus completing the construction of the minimum fuel consumption evaluation model for the hovering point attachment trajectory. Building upon the hovering fuel consumption evaluation model and the minimum fuel consumption evaluation model for the attachment trajectory, a hovering point optimization problem model considering attachment is established. Using the hovering point position and attachment time parameters as optimization variables, and the total fuel consumption of the hovering and attachment processes as the performance index, the interior point method is used to optimize and solve for the hovering position that minimizes the total fuel consumption required for both the hovering and attachment processes.

[0007] The method for optimizing asteroid hovering points that takes into account the attachment process disclosed in this invention includes the following steps:

[0008] Step 1: For the hovering observation mission of the asteroid probe, a fixed-attachment hovering method is adopted for hovering detection. A dynamic model of the asteroid probe's hovering segment is established. Based on the dynamic model, a minimum hovering fuel consumption evaluation model is established with hovering fuel consumption as the optimization index. The minimum hovering fuel consumption at a given hovering point is obtained by optimizing and solving the hovering fuel consumption evaluation model. The hovering fuel consumption evaluation model can also be used in the subsequent Step 3 to construct a model for optimizing the initial position of the probe trajectory during the asteroid hovering and attachment process.

[0009] The specific implementation method of step one is as follows:

[0010] First, a fixed coordinate system Oxyz is established with the asteroid's center of mass as the origin O. In this fixed coordinate system, the hovering state of the probe is represented by its relative position remaining unchanged. Therefore, the dynamic model of the asteroid probe's hovering process is established as follows:

[0011]

[0012] Where ω is the planetary rotation angular velocity, ω×(ω×r) represents the centripetal acceleration (ignoring the probe's control acceleration and disturbance acceleration), g represents the gravitational acceleration vector, T represents the engine thrust, and I... sp G represents the engine's specific impulse. e This represents the Earth's gravitational acceleration constant.

[0013] Based on the hovering process dynamics model, the boundary conditions for the detector during the hovering process are given to the hovering fuel consumption assessment model as follows:

[0014]

[0015] Where r0 represents the detector hovering position, t1 represents the detector hovering time, and m0 represents the detector's initial mass.

[0016] Using hovering fuel consumption as the optimization index, a hovering fuel consumption evaluation model is established as shown in formula (3):

[0017]

[0018] The minimum hovering fuel consumption at a given hovering point is obtained by optimizing and solving the hovering fuel consumption evaluation model (3).

[0019] Step Two: For the asteroid probe's attachment and exploration mission, a dynamic model of the asteroid probe's attachment process is established. Based on the dynamic model, under the condition of a given hovering point, an attachment burnup evaluation model is established using attachment burnup as the optimization index. This model is then solved using a sequential convex optimization method to obtain the minimum attachment burnup required for a given hovering point. This minimum attachment burnup evaluation model can also be used in Step Three to construct a model for optimizing the initial position of the probe's trajectory during the asteroid's hovering and attachment process.

[0020] The specific implementation method for step two is as follows:

[0021] The dynamic equations for the probe during the attachment process are established based on the asteroid fixed coordinate system as follows:

[0022]

[0023] Where 2ω×v represents the Coriolis acceleration.

[0024] Based on the dynamic model of the adhesion process, the boundary conditions for the detector during the adhesion process are given in the minimum burnup evaluation model of the adhesion trajectory as follows:

[0025]

[0026] Where v0 represents the initial velocity of the probe when it begins the attachment mission, r0 represents the hovering position of the probe, m1 represents the initial mass of the probe when it begins the attachment mission, and v f The velocity r represents the detector's terminal velocity. f Indicates the attachment location, t f This represents the final attachment time. For asteroid soft landing problems, the terminal velocity should satisfy v. f The constraint condition is 0. Furthermore, the magnitude of the detector thrust should satisfy the following amplitude constraint:

[0027] 0≤||T||≤T max (6)

[0028] Among them, T max This represents the maximum thrust.

[0029] The fuel consumption during the adhesion process is used as an optimization indicator, as shown below:

[0030]

[0031] To address this optimization index, a minimum fuel consumption evaluation model for the adhesion trajectory is established as shown in formula (8):

[0032]

[0033] The minimum fuel consumption assessment model for the attachment trajectory is transformed into a second-order cone programming problem (SOCP) by constrain relaxation, linearization, and discretization using a sequential convex optimization method. For the nonlinear problem of asteroid gravitational acceleration, it is initially treated as a constant. The minimum fuel consumption assessment model for the attachment trajectory is then iteratively solved using the sequential convex optimization method to obtain the minimum fuel consumption and minimum fuel consumption trajectory required for a given hovering point. This minimum fuel consumption assessment model can also be used in the subsequent step three to construct the initial position optimization model for the asteroid hovering and attachment process.

[0034] Step 3: Based on the minimum hovering fuel consumption evaluation model constructed in Step 1 and the minimum adhesion trajectory fuel consumption evaluation model constructed in Step 2, calculate the hovering fuel consumption and adhesion fuel consumption respectively. Use the total fuel consumption of the hovering detection process and the adhesion detection process as performance indicators, and use the interior point method to determine the optimal hovering point coordinates r0 and the optimal adhesion time t. f An optimized search was conducted to establish a model for optimizing the initial position of the probe trajectory during the asteroid hovering and attachment process. The optimized solution yielded the hovering position with the minimum total burnup.

[0035] The specific implementation method for step three is as follows:

[0036] The sum of hovering fuel consumption and adhesion fuel consumption equals the total fuel consumption during the hovering and adhesion detection process. Combining the minimum hovering fuel consumption evaluation model and the minimum adhesion trajectory fuel consumption evaluation model, the total fuel consumption of the hovering and adhesion processes is used as a performance indicator, with the hovering point coordinates r0 and adhesion time t as the coordinates. f As the optimization variable, the optimization model for the initial position of the probe trajectory during the asteroid hovering and attachment process is established as shown in Equation (9).

[0037]

[0038] The interior point method was used to determine the optimal hovering point coordinates r0 and the optimal attachment time t. fThe optimization search process for the initial position optimization problem of the asteroid hovering and attachment process includes two stages: hovering and attachment. The fuel consumption calculation for the hovering process relies on the minimum hovering fuel consumption evaluation model; the fuel consumption trajectory optimization for the attachment process relies on the minimum attachment trajectory fuel consumption evaluation model. The interior point method is used to optimize the parameters r0 and t. f Through iterative calculations, the initial hovering position is optimized, yielding the optimal hovering point and the optimal attachment time t. f .

[0039] The process also includes step four, which uses the optimal hovering point obtained from step three as the initial position of the asteroid probe's hovering and attachment trajectory. The minimum burnup evaluation model for the attachment trajectory constructed in step two is used to optimize and obtain the optimal burnup trajectory, thereby reducing the total burnup of the probe during the hovering and attachment phases.

[0040] Beneficial effects:

[0041] 1. The present invention discloses an initial position optimization method for asteroid hovering / attachment probe trajectories. It constructs a minimum hovering burnup evaluation model to address the optimization search problem for asteroid probe hovering positions, enabling the evaluation and optimization of burnup during the hovering observation phase. The minimum burnup evaluation model for the attachment trajectory is constructed using a solution method based on sequential convex optimization, which can optimize the burnup of the asteroid probe during the attachment probe phase while simultaneously satisfying multiple constraints such as probe thrust limiting and initial / final state constraints.

[0042] 2. The method for optimizing the initial position of asteroid hovering / attachment probe trajectory disclosed in this invention uses the total fuel consumption of the hovering observation process and the attachment probe process as a performance index to optimize the parameters of the hovering point coordinates and the attachment time, thereby obtaining the optimal hovering point coordinates and the optimal attachment time, and obtaining the trajectory with optimal fuel consumption, which can effectively reduce the fuel consumption of the probe during the hovering and attachment phases.

[0043] 3. The method for optimizing the initial position of asteroid hovering / attachment detection trajectory disclosed in this invention, based on achieving the beneficial effects 1 and 2, can optimize and search for the optimal hovering point of asteroids corresponding to different target attachment points, and is applicable to the problem of fuel consumption optimization under different hovering times. Attached Figure Description

[0044] Figure 1 Flowchart of the method for optimizing the initial position of asteroid hovering / attachment probe trajectory.

[0045] Figure 2 The optimal adhesion trajectory for fuel consumption at different hovering points.

[0046] Figure 3 The attachment trajectory is the optimal hovering point for the asteroid.

[0047] Figure 4 The three-axis velocity curves of the detector attachment process corresponding to the optimal hovering point are shown.

[0048] Figure 5 The thrust curve for the detector attachment process corresponding to the optimal hovering point.

[0049] Figure 6 The attachment trajectory for the optimal hovering point under different hovering times. Detailed Implementation

[0050] To better illustrate the purpose and advantages of the present invention, the following description, in conjunction with an example and corresponding drawings, further explains the invention.

[0051] Assuming the asteroid probe has a mass of m = 500 kg and a maximum thrust T... max =20N, asteroid rotational angular velocity w = 3.3139e -4 rad / s, Earth's gravitational acceleration constant g e = 9.807 m / s 2 Attachment position r f =[-153.7,6044,0] T Engine specific impulse I sp =400.

[0052] like Figure 1 As shown in the figure, the method for optimizing the initial position of an asteroid hovering / attachment probe trajectory disclosed in this embodiment has the following specific implementation steps:

[0053] Step 1: For the hovering observation mission of the asteroid probe, a fixed-attachment hovering method is adopted for hovering detection. A dynamic model of the asteroid probe's hovering segment is established. Based on the dynamic model, a minimum hovering fuel consumption evaluation model is established with hovering fuel consumption as the optimization index. The minimum hovering fuel consumption at a given hovering point is obtained by optimizing and solving the hovering fuel consumption evaluation model. The hovering fuel consumption evaluation model can also be used in the subsequent Step 3 to construct a model for optimizing the initial position of the probe trajectory during the asteroid hovering and attachment process.

[0054] First, a fixed coordinate system Oxyz is established with the asteroid's center of mass as the origin O. In this fixed coordinate system, the hovering state of the probe is represented by its relative position remaining unchanged. Therefore, the dynamic equations for the asteroid probe's hovering process are:

[0055]

[0056] Where ω is the planetary rotation angular velocity, ω×(ω×r) represents the centripetal acceleration (ignoring the probe's control acceleration and disturbance acceleration), g represents the gravitational acceleration vector, T represents the engine thrust, and I...sp G represents the engine's specific impulse. e This represents the Earth's gravitational acceleration constant.

[0057] Based on the hovering process dynamics model, the boundary conditions for the detector during the hovering process are given to the hovering fuel consumption assessment model as follows:

[0058]

[0059] Where r0 represents the detector hovering position, t1 represents the detector hovering time, and m0 represents the detector's initial mass.

[0060] Using hovering fuel consumption as the optimization index, a hovering fuel consumption evaluation model is established as shown in formula (3):

[0061]

[0062] The minimum hovering fuel consumption at a given hovering point is obtained by optimizing and solving the hovering fuel consumption evaluation model (3).

[0063] Step Two: For the asteroid probe's attachment and exploration mission, a dynamic model of the asteroid probe's attachment process is established. Based on the dynamic model, under the condition of a given hovering point, an attachment burnup evaluation model is established using attachment burnup as the optimization index. This model is then solved using a sequential convex optimization method to obtain the minimum attachment burnup required for a given hovering point. This minimum attachment burnup evaluation model can also be used in Step Three to construct a model for optimizing the initial position of the probe's trajectory during the asteroid's hovering and attachment process.

[0064] The dynamic equations for the probe during the attachment process are established based on the asteroid fixed coordinate system as follows:

[0065]

[0066] Where 2ω×v represents the Coriolis acceleration.

[0067] Based on the dynamic model of the adhesion process, the boundary conditions for the detector during the adhesion process are given in the minimum burnup evaluation model of the adhesion trajectory as follows:

[0068]

[0069] Where v0 represents the initial velocity of the probe when it begins the attachment mission, r0 represents the hovering position of the probe, m1 represents the initial mass of the probe when it begins the attachment mission, and v f The velocity r represents the detector's terminal velocity. f Indicates the attachment location, t f This represents the final attachment time. For asteroid soft landing problems, the terminal velocity should satisfy v. fThe constraint condition is 0. Furthermore, the magnitude of the detector thrust should satisfy the following amplitude constraint:

[0070] 0≤||T||≤T max (6)

[0071] Among them, T max This represents the maximum thrust.

[0072] The fuel consumption during the adhesion process is used as an optimization indicator, as shown below:

[0073]

[0074] To address this optimization index, a minimum fuel consumption evaluation model for the adhesion trajectory is established as shown in formula (8):

[0075]

[0076] The minimum fuel consumption assessment model for the attachment trajectory is transformed into a second-order cone programming problem (SOCP) by constrain relaxation, linearization, and discretization using a sequential convex optimization method. For the nonlinear problem of asteroid gravitational acceleration, it is initially treated as a constant. The minimum fuel consumption assessment model for the attachment trajectory is then iteratively solved using the sequential convex optimization method to obtain the minimum fuel consumption and minimum fuel consumption trajectory required for a given hovering point. This minimum fuel consumption assessment model can also be used in the subsequent step three to construct the initial position optimization model for the asteroid hovering and attachment process.

[0077] Based on the minimum hovering fuel consumption assessment model and the minimum attachment trajectory fuel consumption assessment model, the detector hovering time t1 = 3600s, and the attachment time is set to t f =3000s, hover point coordinates r0 are set to [2950, ​​13640, 0] T [4950,13640,0] T and [6950,13640,0] T (Unit / m), substituting this into the minimum hovering fuel consumption evaluation model and the minimum adhesion trajectory fuel consumption evaluation model, the optimal adhesion trajectory for different hovering points is obtained as follows: Figure 2 As shown, the total fuel consumption corresponding to hovering point 1 is 1.195 kg; the total fuel consumption corresponding to hovering point 2 is 1.186 kg; and the total fuel consumption corresponding to hovering point 3 is 1.312 kg. The minimum hovering fuel consumption evaluation model and the minimum adhesion trajectory fuel consumption evaluation model can calculate the total fuel consumption corresponding to a given hovering point and optimize it to obtain the fuel-optimal adhesion trajectory.

[0078] Step 3: Based on the minimum hovering fuel consumption evaluation model constructed in Step 1 and the minimum adhesion trajectory fuel consumption evaluation model constructed in Step 2, calculate the hovering fuel consumption and adhesion fuel consumption respectively. Use the total fuel consumption of the hovering detection process and the adhesion detection process as performance indicators, and use the interior point method to determine the optimal hovering point coordinates r0 and the optimal adhesion time t. f An optimized search was conducted to establish a model for optimizing the initial position of the probe trajectory during the asteroid hovering and attachment process. The optimized solution yielded the hovering position with the minimum total burnup.

[0079] The sum of hovering fuel consumption and adhesion fuel consumption equals the total fuel consumption during the hovering and adhesion detection process. Combining the minimum hovering fuel consumption evaluation model and the minimum adhesion trajectory fuel consumption evaluation model, the total fuel consumption of the hovering and adhesion processes is used as a performance indicator, with the hovering point coordinates r0 and adhesion time t as the coordinates. f As the optimization variable, the optimization model for the initial position of the probe trajectory during the asteroid hovering and attachment process is established as shown in Equation (9).

[0080]

[0081] The interior point method was used to determine the optimal hovering point coordinates r0 and the optimal attachment time t. f The optimization search process for the initial position optimization problem of the asteroid hovering and attachment process includes two stages: hovering and attachment. The fuel consumption calculation for the hovering process relies on the minimum hovering fuel consumption evaluation model; the fuel consumption trajectory optimization for the attachment process relies on the minimum attachment trajectory fuel consumption evaluation model. The interior point method is used to optimize the parameters r0 and t. f Through iterative calculations, the initial hovering position is optimized, yielding the optimal hovering point and the optimal attachment time t. f .

[0082] With a hovering time of t1 = 3600s, the optimal hovering point coordinates and the best attachment time t1 are determined using a problem model that optimizes the initial position of the probe trajectory during the asteroid hovering and attachment process. f The optimal hovering point attachment trajectory of the asteroid is obtained by performing optimization and solution as follows: Figure 3 As shown, the optimal hovering point coordinates corresponding to this attachment point are obtained as r0 = [4949.3, 13639.3, 0]. T The minimum total fuel consumption is 1.04 kg.

[0083] The triaxial velocity curve of the detector attachment process corresponding to the optimal hovering point is as follows: Figure 4 As shown, the probe's final velocity approached 0, achieving a soft landing.

[0084] The thrust curve of the detector attachment process corresponding to the optimal hovering point is as follows: Figure 5As shown in the figure, the thrust curve shows that the thrust pattern basically satisfies the optimal bang-bang control pattern. The engine is shut down in the middle stage, allowing the probe to move freely, thus achieving the purpose of saving fuel consumption.

[0085] Hovering times t1 were set to 1800s, 3600s, and 7200s, respectively, and comparative simulations were performed to obtain the attachment trajectories of the optimal hovering points for different hovering times, as shown below. Figure 6 As shown, the optimization model for the initial position of the asteroid's hovering and attachment process trajectory was successfully solved under different hovering times, yielding the optimal hovering point coordinates r0 that minimize total burnup, which are [5995.4, 11209.6, 0]. T [4949.3,13639.3,0] T and [2932.9,14479.6,0] T Simulation results show that this method can be applied to fuel consumption optimization problems under different hovering times.

[0086] The above detailed description further illustrates the purpose, technical solution, and beneficial effects of the invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for optimizing the initial position of an asteroid hovering / attachment probe trajectory, characterized by: This method is based on modeling the asteroid in a fixed rotating coordinate system, establishing dynamic equations that include centripetal acceleration and Coriolis acceleration terms caused by the asteroid's rotation, and includes the following steps: Step 1: Establish a hovering dynamics model for the detector. Construct a minimum hovering fuel consumption evaluation model with the minimum hovering fuel consumption integral as the index, and solve for the minimum hovering fuel consumption corresponding to a given hovering point r0. ; Step 2: Establish a detector attachment dynamics model, and construct an attachment fuel consumption evaluation model with the minimum integral of attachment fuel consumption as the index. Perform constraint relaxation, linearization, and discretization on the model sequentially to transform it into a second-order cone programming problem. Solve this problem iteratively using sequential convex optimization to obtain the given r0 and attachment termination time. Corresponding minimum adhesion fuel consumption The constraints in the attachment optimization process include thrust amplitude constraints, zero velocity constraints at the initial hovering moment, and terminal zero velocity constraints at the soft landing moment on the satellite surface. Step 3: Constructing Total Fuel Consumption Indicators Using the hovering point coordinates r0 and the attachment terminal time For the outer optimization variables, a model is established to optimize the initial position of the probe trajectory during the asteroid hovering and attachment process. An interior-point method is used for iterative optimization. After each update of r0, the attachment burnup is recalculated using the model from step two. Through a double-layer nested iteration of inner-layer sequential convex optimization and outer-layer interior-point method, the optimal hovering position and optimal attachment time with the minimum total burnup are obtained. .

2. The method for optimizing the initial position of an asteroid hovering / attachment probe trajectory as described in claim 1, characterized in that: It also includes step four, which uses the optimal hovering position obtained from step three as the initial position of the asteroid probe's hovering and attachment trajectory, and uses the minimum burn-out evaluation model for the attachment trajectory constructed in step two to optimize and obtain the optimal burn-out trajectory, thereby reducing the total burn-out of the probe's hovering and attachment phases.

3. The method for optimizing the initial position of an asteroid hovering / attachment probe trajectory as described in claim 1 or 2, characterized in that: The specific implementation method of step one is as follows: First, a fixed coordinate system Oxyz is established with the asteroid's center of mass as the origin O. In this fixed coordinate system, the hovering state of the probe is represented by its relative coordinate position remaining unchanged. Therefore, the dynamic model of the asteroid probe's hovering process is established as follows: (1) Where ω is the planetary rotation angular velocity, ω×(ω×r) represents the centripetal acceleration (ignoring the probe's control acceleration and disturbance acceleration), g represents the gravitational acceleration vector, T represents the engine thrust, and I... sp G represents the engine's specific impulse. e Represents the Earth's gravitational acceleration constant; Based on the hovering process dynamics model, the boundary conditions for the detector during the hovering process are given to the hovering fuel consumption assessment model as follows: (2) Where r0 represents the hovering position of the detector, t1 represents the hovering time of the detector, and m0 represents the initial mass of the detector; Using hovering fuel consumption as the optimization index, a hovering fuel consumption evaluation model is established as shown in formula (3): (3) The minimum hovering fuel consumption at a given hovering point is obtained by optimizing and solving the hovering fuel consumption evaluation model.

4. The method for optimizing the initial position of an asteroid hovering / attachment probe trajectory as described in claim 3, characterized in that: The specific implementation method for step two is as follows: The dynamic equations of the probe during the attachment process are established based on the asteroid fixed coordinate system as follows: (4) Where 2ω×v represents the Coriolis acceleration; Based on the dynamic model of the adhesion process, the boundary conditions for the detector during the adhesion process are given in the minimum burnup evaluation model of the adhesion trajectory as follows: (5) Where v0 represents the initial velocity of the probe when it begins the attachment mission, r0 represents the hovering position of the probe, m1 represents the initial mass of the probe when it begins the attachment mission, and v f The velocity r represents the detector terminal velocity. f Indicates the attachment location, t f This indicates the final attachment time; for asteroid soft landing problems, the terminal velocity should satisfy v. f The constraint condition is 0; in addition, the magnitude of the detector thrust should satisfy the following amplitude constraint: (6) Among them, T max This is expressed as the maximum thrust. The fuel consumption during the adhesion process is used as an optimization indicator, as shown below: (7) To address this optimization index, a minimum fuel consumption evaluation model for the adhesion trajectory is established as shown in formula (8): (8) Based on the sequential convex optimization method, the minimum fuel consumption evaluation model of the attachment trajectory is subjected to constraint relaxation, linearization, and discretization to convex processing, transforming it into a second-order cone programming problem (SOCP). For the nonlinear problem of asteroid gravitational acceleration, it is first treated as a constant, and the minimum fuel consumption evaluation model of the attachment trajectory is iteratively solved using the sequential convex optimization method to obtain the minimum attachment fuel consumption and minimum fuel consumption trajectory required for a given hovering point. The minimum fuel consumption evaluation model of the attachment trajectory can also be used in the subsequent step three to construct the initial position optimization problem model of the asteroid hovering and attachment process detection trajectory.

5. The method for optimizing the initial position of an asteroid hovering / attachment probe trajectory as described in claim 4, characterized in that: The specific implementation method for step three is as follows: The sum of hovering fuel consumption and adhesion fuel consumption equals the total fuel consumption during the hovering and adhesion detection process. Combining the minimum hovering fuel consumption evaluation model and the minimum adhesion trajectory fuel consumption evaluation model, the total fuel consumption of the hovering and adhesion processes is used as a performance indicator, with the hovering point coordinates r0 and adhesion time t as the performance metrics. f As the optimization variable, the optimization model for the initial position of the probe trajectory during the asteroid hovering and attachment process is established as shown in Equation (9). (9) The interior point method was used to determine the optimal hovering point coordinates r0 and the optimal attachment time t. f The optimization search process for the initial position optimization problem of the asteroid hovering and attachment process includes two stages: hovering and attachment. The fuel consumption calculation for the hovering process relies on the minimum hovering fuel consumption evaluation model; the fuel consumption trajectory optimization for the attachment process relies on the minimum attachment trajectory fuel consumption evaluation model. The interior point method is used to optimize the parameters r0 and t. f Through iterative calculations, the initial hovering position is optimized, yielding the optimal hovering point and the optimal attachment time t. f .

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