Small celestial body surface bounce movement attitude maneuver control method

Abstract

The small celestial body surface bounce movement posture maneuvering control method disclosed by the application belongs to the field of deep space exploration.The method of the application is as follows: for the posture maneuvering problem of the detector bounce movement, the dynamic equation of the detector after jumping in the small celestial body fixed coordinate system and the small celestial body surface coordinate system is established respectively.The change of the posture of the detector after jumping will make the next bounce process after collision unpredictable due to the uncertainty of the moment of inertia and the external disturbance.By establishing the bounce movement error posture dynamic model of the detector containing the total disturbance of the uncertainty of the moment of inertia and the external environmental disturbance, the sliding surface containing the finite time control is designed, and the convergence efficiency of the state of the detector system and the posture maneuvering control precision are improved.On the basis of the finite time sliding surface, the adaptive mechanism is introduced, the robustness of the detector system is enhanced, and then the detector can be maneuvered to the target collision posture at a faster speed and better precision.

Description

Technical Field

[0001] The present invention relates to a method for maneuvering the pre-landing attitude of a probe by using a finite-time adaptive sliding mode control algorithm during the bouncing movement on the surface of a small celestial body, and belongs to the field of deep space exploration. Background Art

[0002] In the exploration of small celestial bodies, mobile exploration on the surface is an important method. Unlike the surface environment of planets, the gravity of small celestial bodies is extremely small, and the surface environment is complex and changeable. It is extremely difficult for traditional wheeled probes to walk and control on their surfaces. Currently, there is a surface movement method called bouncing. Bouncing movement has the advantages of being able to cross obstacles and travel long distances in a short time. However, if no control is applied, the posture of the probe after takeoff will change due to initial errors, parameter uncertainties, and environmental disturbances, making the trajectory of the probe after landing and collision unpredictable, and the probe will not be able to reach the target area. Therefore, it is necessary to study methods to control the posture of the probe to maneuver to the target posture within a limited time before colliding with the ground, so that the probe collides with the ground in a predetermined posture.

[0003] Currently available methods for controlling the attitude of small astronomical probes primarily include PID control algorithms and fuzzy control algorithms. The PID control algorithm is a feedback-based control method that achieves system control by adjusting the proportional, integral, and differential parameters of the controller. However, it is sensitive to system stability and interference immunity. Improper parameter adjustment can lead to a decrease in system stability and interference immunity. Fuzzy control algorithms, based on fuzzy logic, achieve system control by fuzzifying and defuzzifying the input and output, respectively, based on the relationship between the input and output. However, the fuzzy control algorithm's control rules are relatively complex, making it difficult to optimize and debug the control system. Summary of the Invention

[0004] The main technical problem solved by the method for maneuvering the attitude of bouncing movement on the surface of a small celestial body disclosed in the present invention is that the moment of inertia of the cube detector has uncertainty, which will cause initial errors when the detector takes off. At the same time, the detector will be disturbed by the external environment on the surface of the small celestial body, resulting in unpredictable changes in the attitude of the detector after taking off. The attitude of the detector is stabilized to the target collision attitude by designing a sliding mode control method including finite time control; at the same time, an adaptive mechanism is added to the sliding mode controller to compensate for the model uncertainty and disturbance of the system, thereby improving the robustness of the system. The present invention realizes the attitude maneuvering control of the cube-shaped detector during the bouncing movement process on the surface of a small celestial body within a finite time by constructing a detector bouncing movement error attitude dynamics model including the uncertainty of its own moment of inertia and the total interference of the external environment disturbance, so as to make the detector system have good robustness and improve the accuracy and efficiency of attitude control.

[0005] The present invention is achieved through the following technical solutions.

[0006] The present invention discloses a method for controlling the attitude maneuvering of the bounce movement of a small celestial body on the surface. Aiming at the attitude maneuvering problem of the bounce movement of the detector, the dynamic equations of the detector after taking off are established in the fixed coordinate system of the small celestial body and the coordinate system of the surface of the small celestial body, respectively. After the detector takes off, due to the uncertainty of the moment of inertia and external interference, the change of its attitude will make the next bounce process after the collision unpredictable. By establishing an attitude dynamic model of the detector bounce movement error including the uncertainty of its own moment of inertia and the total interference of the external environment disturbance, a sliding surface including finite time control is designed to improve the convergence efficiency of the detector system state and the accuracy of attitude maneuvering control. An adaptive mechanism is introduced on the basis of the finite time sliding surface to enhance the robustness of the detector system, thereby ensuring that the detector can maneuver to the target collision attitude at a faster speed and better accuracy.

[0007] The present invention discloses a method for maneuvering control of the surface bouncing movement of a small celestial body, comprising the following steps:

[0008] Step 1: Establish the detector's fixed coordinate system O on the small celestial body. B -X B Y B Z B And the dynamic equation of the bouncing trajectory in the surface coordinate system O-XYZ.

[0009] Regarding the single bounce motion problem of the probe, in the fixed coordinate system of the small celestial body, the dynamic equation of the probe after take-off is expressed as

[0010]

[0011] Among them, r B 、v Bare the position and velocity vector of the detector respectively, ω is the spin angular velocity of the small celestial body, and g is the gravitational acceleration vector of the small celestial body.

[0012] In the surface coordinate system, the dynamic equation of the detector is:

[0013]

[0014] Among them, r and v are the position and velocity vectors of the detector respectively, and ρ is the position vector of the origin of the surface coordinate system relative to the center of the small celestial body. is the matrix for transforming from the body coordinate system to the surface coordinate system.

[0015] Step 2: Establish the attitude dynamics model and attitude kinematics model of the detector in the body coordinate system, define the error angular velocity and error quaternion of the detector, and solve the rotation matrix of the body coordinate system relative to the target coordinate system. Since the rotational inertia of the detector is uncertain, the rotational inertia J is divided into deterministic and uncertainty △J, and the uncertainty of the moment of inertia is combined with the external interference into the total interference suffered by the detector. That is, the total interference suffered by the detector is used to characterize the initial error of the cube-shaped detector caused by the uncertainty of its own moment of inertia and the interference of the external environment when it takes off, and then the detector bouncing movement error posture dynamics model including the total interference of its own moment of inertia uncertainty and external environmental disturbance is obtained.

[0016] In the body coordinate system, the attitude dynamics model of the cube detector is constructed as follows:

[0017]

[0018] Among them, ω is the attitude angular velocity of the detector, J is the moment of inertia matrix of the detector, u is the control torque, d is the external interference torque, and the external interference torque is defined as a Gaussian white noise with bounded norm, that is,

[0019] The quaternion of the detector body coordinate system relative to the inertial coordinate system is Angular velocity is ω=[ω x ω y ω z ] T , then the attitude kinematics of the detector is:

[0020]

[0021] Among them, q0 is the quaternion's standard part, q v is the vector part of the quaternion, and

[0022]

[0023] The expected quaternion of the probe during flight is q f , the desired angular velocity is ω f , define the error quaternion as q e ,have:

[0024]

[0025] Then the rotation matrix from the target coordinate system to the body coordinate system is:

[0026]

[0027] The error angular velocity of the body coordinate system relative to the target coordinate system is defined as:

[0028]

[0029] Combining equations (4), (6), and (8), the attitude kinematic equation of the detector based on the error quaternion is:

[0030]

[0031] Substituting equation (8) into equation (3), the attitude dynamics model of the detector based on the error angular velocity is obtained as follows:

[0032]

[0033] Considering the uncertainty of the detector's moment of inertia, the moment of inertia J is divided into deterministic and uncertainty △J, namely Substituting into formula (11) we get:

[0034]

[0035] Among them, the uncertainty of the moment of inertia is combined with the external interference to form the total interference d e for:

[0036]

[0037] The total interference d received by the detector e The initial error caused by the uncertainty of the cube-shaped detector's own moment of inertia and the interference of the external environment when it takes off is characterized, and then the detector bouncing movement error attitude dynamics model including the total interference of the uncertainty of its own moment of inertia and the external environment disturbance is obtained as shown in formula (12).

[0038] Step 3: The cube probe's flight time during the bouncing motion is finite. A terminal sliding surface is constructed that includes the exponential term of the vector of the probe's attitude quaternion. A Lyapunov function is constructed to verify the terminal sliding surface. The finite-time control principle is used to verify that the terminal sliding surface converges within a finite time. This terminal sliding surface enables the cube probe to reach the target attitude within a finite time.

[0039] The flight time of the cube detector during the bouncing movement is limited. The terminal sliding mode surface containing the vector exponential term of the detector attitude quaternion is constructed as shown in formula (13):

[0040] s=ω e +ksig β (q ev ) (13)

[0041] Among them, k is a positive constant, sig β (q ev )=[sig β (q e1 )sig β (q e2 )sig β (q e3 )] T , and sig β (q ei )=sgn(q ei )|q ei | β , i=1,2,3,0<β<1.

[0042] Construct the Lyapunov function as:

[0043]

[0044] Derivative of the above formula (14) yields:

[0045]

[0046] When the detector system state reaches the sliding surface, s = 0, that is, ω = -ksgn β (q ev ), and substituting into formula (15) we get:

[0047]

[0048] again but Right now:

[0049]

[0050] Formula (17) satisfies the finite time stability theorem, thereby verifying that the terminal sliding surface converges in a finite time. Furthermore, by using the terminal sliding surface including the vector exponential term of the detector attitude quaternion as shown in formula (13), it is possible to ensure that the cube detector reaches the target attitude in a finite time.

[0051] Step 4: Based on the initial error caused by the uncertainty of the cube-shaped detector's own moment of inertia when taking off in step 2 and the interference of the external environment, the total interference is dynamically estimated through an adaptive mechanism on the terminal sliding surface described in step 3, and the exponential reaching law is selected to design a finite-time stable sliding mode control law. The estimated dynamic total interference term is introduced into the finite-time stable sliding mode control law to obtain a finite-time adaptive sliding mode control law, thereby eliminating the influence of the uncertainty of the cube detector's moment of inertia and environmental disturbances on the stability of the detector system, and improving the robustness of the detector attitude control system.

[0052] Derivative the terminal sliding mode surface equation (13) on both sides including the vector exponential term of the detector attitude quaternion, and substitute equation (9) into it to obtain:

[0053]

[0054] Multiply both sides of equation (18) by Substituting formula (12) into the equation, we get:

[0055]

[0056] Selection exponential reaching law Substituting into the above formula, we get the finite-time adaptive sliding mode control law as follows:

[0057]

[0058] in, is the upper limit of perturbation ||d e || ∞ The estimated value of c>0 is the adaptive speed constant, and ε is a positive constant.

[0059] Select the Lyapunov function as:

[0060]

[0061] Taking the derivative, we get:

[0062]

[0063] Therefore, the sliding surface tends to be consistent and asymptotically stable and the system can converge to the sliding surface in a finite time.

[0064] Step 5: Substitute the cube detector finite-time adaptive sliding mode control law obtained in step 4 into the detector bouncing movement error attitude dynamics model described in step 2, which includes the uncertainty of its own rotational inertia and the total interference of external environmental disturbances, and then realize the attitude maneuvering control of the cube-shaped detector during the bouncing movement on the surface of the small celestial body within a finite time, thereby improving the robustness of the detector system and improving the attitude control accuracy and efficiency.

[0065] Beneficial effects:

[0066] 1. The present invention discloses a method for maneuvering the attitude of a small celestial body on the surface of a bouncing object, constructs a terminal sliding surface including the exponential term of the vector part of the detector attitude quaternion, and constructs a Lyapunov function to verify the terminal sliding surface. The finite time control principle is used to verify that the terminal sliding surface converges in a finite time, thereby avoiding the problem that the closed-loop system state of the detector needs to converge to zero when time tends to infinity, thereby improving the convergence efficiency of the detector system.

[0067] 2. The present invention discloses a method for maneuvering the attitude of a small celestial body bouncing on the surface. It uses the total interference received by the detector to characterize the initial error of the cube-shaped detector caused by the uncertainty of its own moment of inertia and the interference of the external environment when it takes off, and obtains a dynamic model of the detector's bouncing error attitude including the total interference of the uncertainty of its own moment of inertia and the disturbance of the external environment. An adaptive mechanism is introduced into the finite-time sliding mode control law to eliminate the influence of the total interference on the stability of the detector control system, thereby improving the robustness of the system.

[0068] 3. The present invention discloses a method for maneuvering the attitude of a small celestial body bouncing on the surface, establishes an attitude dynamics model of the detector's bouncing movement error, and constructs a finite-time adaptive sliding mode control law to eliminate the detector's own uncertainty interference and external interference, so that the detector can collide with the ground in the target attitude and ensure the controllability of the next bouncing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] Figure 1 This is a flow chart of the method for maneuvering control of the surface bouncing movement of a small celestial body according to the present invention;

[0070] Figure 2 is a quaternion change curve of the attitude control of the probe in the example of the present invention during flight;

[0071] Figure 3 is the angular velocity change curve of the attitude control of the probe in the example of the present invention during flight;

[0072] Figure 4 This is a diagram of the bouncing movement trajectory of the detector in the example of the present invention on the surface of a simulated small celestial body. DETAILED DESCRIPTION

[0073] In order to better illustrate the purpose and advantages of the present invention, the invention is further described below with reference to the accompanying drawings and examples.

[0074] like Figure 1 As shown, the method for controlling the surface bouncing trajectory of a weakly gravitational small celestial body disclosed in this embodiment is specifically implemented in the following steps:

[0075] Step 1: Establish the detector's fixed coordinate system O on the small celestial body. B -X B Y B Z B and the dynamic equations of the bounce trajectory in the surface coordinate system O-XYZ. Taking the small celestial body Eros as an example, the method disclosed in the present invention was simulated and verified under simulated surface terrain conditions. The physical parameters of the small celestial body are: three-dimensional dimensions 34.4km×11.2km×11.2km, mass 6.69×1015kg, density 2.67×103kg / m 3 , the angular velocity of the spin around its principal axis of inertia is 3.31×10 -4 rad / s, and the gravitational constant is 6.67×10 -11 Nm 2 / kg 2 The surface coordinate system is established with the detector's initial take-off position as the origin, and the initial take-off position is r0 = [0,0,0] T m, the detector target point position is r d =[50,50,0] T m.

[0076] Regarding the single bounce motion problem of the probe, in the fixed coordinate system of the small celestial body, the dynamic equation of the probe after take-off is expressed as

[0077]

[0078] Among them, r B 、v B are the position and velocity vector of the detector respectively, ω is the spin angular velocity of the small celestial body, and g is the gravitational acceleration vector of the small celestial body.

[0079] In the surface coordinate system, the dynamic equation of the detector is:

[0080]

[0081] Among them, r and v are the position and velocity vectors of the detector respectively, and ρ is the position vector of the origin of the surface coordinate system relative to the center of the small celestial body. is the matrix for transforming from the body coordinate system to the surface coordinate system.

[0082] Step 2: Establish the attitude dynamics model and attitude kinematics model of the detector in the body coordinate system, define the error angular velocity and error quaternion of the detector, and solve the rotation matrix of the body coordinate system relative to the target coordinate system. Since the rotational inertia of the detector is uncertain, the rotational inertia J is divided into deterministic and uncertainty △J, and the uncertainty of the moment of inertia is combined with the external interference into the total interference suffered by the detector. That is, the total interference suffered by the detector is used to characterize the initial error of the cube-shaped detector caused by the uncertainty of its own moment of inertia and the interference of the external environment when it takes off, and then the detector bouncing movement error posture dynamics model including the total interference of its own moment of inertia uncertainty and external environmental disturbance is obtained.

[0083] The determination part of the detector's moment of inertia is The uncertainty ΔJ is taken as 2% of the nominal value, d = 0.0001 N·m.

[0084] In the body coordinate system, the attitude dynamics model of the cube detector is constructed as follows:

[0085]

[0086] Among them, ω is the attitude angular velocity of the detector, J is the moment of inertia matrix of the detector, u is the control torque, d is the external interference torque, and it is assumed that the external interference torque is a Gaussian white noise with bounded norm, that is,

[0087] Assume that the quaternion of the detector body coordinate system relative to the inertial coordinate system is Angular velocity is ω=[ω x ω y ω z ] T , then the attitude kinematics of the detector is:

[0088]

[0089] Among them, q0 is the quaternion's standard part, q v is the vector part of the quaternion, and

[0090]

[0091] The expected quaternion of the probe during flight is q f =[1,0,0,0] T , the desired angular velocity is ω f =[0,0,0] T , define the error quaternion as q e ,have:

[0092]

[0093] Then the rotation matrix from the target coordinate system to the body coordinate system can be obtained as:

[0094]

[0095] The error angular velocity of the body coordinate system relative to the target coordinate system is defined as:

[0096] ω e =ω-C e ω f (30)

[0097] Combining equations (26), (28), and (30), we can obtain the attitude kinematic equation of the detector based on the error quaternion:

[0098]

[0099] Substituting equation (30) into equation (25), the attitude dynamics model of the detector based on the error angular velocity is obtained as follows:

[0100]

[0101] Considering the uncertainty of the detector's moment of inertia, the moment of inertia J is divided into deterministic and uncertainty △J, namely Substituting into formula (33) we get:

[0102]

[0103] Among them, the uncertainty of the moment of inertia is combined with the external interference to form the total interference d e for:

[0104]

[0105] Step 3: The cube probe's flight time during the bouncing motion is finite. A terminal sliding surface is constructed that includes the exponential term of the vector of the probe's attitude quaternion. A Lyapunov function is constructed to verify the terminal sliding surface. The finite-time control principle is used to verify that the terminal sliding surface converges within a finite time. This terminal sliding surface enables the cube probe to reach the target attitude within a finite time.

[0106] The flight time of the cube detector during the bouncing movement is limited. The terminal sliding mode surface containing the vector exponential term of the detector attitude quaternion is constructed as shown in formula (35):

[0107] s=ω e +ksig β (q ev ) (35)

[0108] Where k = 0.1, sig β (q ev )=[sig β (q e1 ) sig β (q e2 ) sig β (q e3 )] T , and sig β (q ei )=sgn(q ei )|q ei | β , i=1,2,3,β=0.8.

[0109] Select the Lyapunov function as:

[0110]

[0111] Derivative of the above formula (36) yields:

[0112]

[0113] When the system state reaches the sliding surface, s=0, that is, ω=-ksgn β (q ev ), substituting into formula (37) we can get:

[0114]

[0115] again but Right now:

[0116]

[0117] Formula (39) satisfies the finite time stability theorem, thereby verifying that the terminal sliding surface converges in a finite time. Furthermore, through the terminal sliding surface including the vector exponential term of the detector attitude quaternion as shown in formula (35), it can be ensured that the cube detector reaches the target attitude in a finite time.

[0118] Step 4: Based on the initial error caused by the uncertainty of the cube-shaped detector's own moment of inertia when taking off in step 2 and the interference of the external environment, the total interference is dynamically estimated through an adaptive mechanism on the terminal sliding surface described in step 3, and the exponential reaching law is selected to design a finite-time stable sliding mode control law. The estimated dynamic total interference term is introduced into the finite-time stable sliding mode control law to obtain a finite-time adaptive sliding mode control law, thereby eliminating the influence of the uncertainty of the cube detector's moment of inertia and environmental disturbances on the stability of the detector system, and improving the robustness of the detector attitude control system.

[0119] Derivative the terminal sliding mode surface equation (35) containing the vector exponential term of the detector attitude quaternion, and substitute equation (31) into it to obtain:

[0120]

[0121] Multiply both sides of equation (40) by Substituting formula (34) into the equation, we get:

[0122]

[0123] Selection exponential reaching law Substituting into the above formula, we get the finite-time adaptive sliding mode control law as follows:

[0124]

[0125] in, is the upper limit of perturbation ||d e || ∞ The estimated value of c=10 is the adaptive speed constant, ε=0.8.

[0126] Select the Lyapunov function as:

[0127]

[0128] Taking the derivative, we get:

[0129]

[0130] Therefore, the sliding surface tends to be consistent and asymptotically stable and the system can converge to the sliding surface in a finite time.

[0131] Step 5: Substitute the cube detector finite-time adaptive sliding mode control law obtained in step 4 into the detector bouncing movement error attitude dynamics model described in step 2, which includes the uncertainty of its own rotational inertia and the total interference of external environmental disturbances, and then realize the attitude maneuvering control of the cube-shaped detector during the bouncing movement on the surface of the small celestial body within a finite time, thereby improving the robustness of the detector system and improving the attitude control accuracy and efficiency.

[0132] like Figure 2 and Figure 3 As shown in Figure 3, when the probe reaches the attitude controllable flight altitude 3.4 seconds after takeoff, the probe begins attitude control and completes the attitude maneuver at 90 seconds. The total flight time of the probe is 446 seconds. Figure 4As shown in the figure, the probe completed a hopping motion on the surface of a small celestial body. The simulation results show that, despite the uncertainty of the probe's own moment of inertia and the influence of external interference, the method described in this invention quickly and robustly achieves the probe's attitude maneuver, enabling the probe to reach the target attitude.

[0133] The above specific description further illustrates the purpose, technical solutions and beneficial effects of the invention in detail. 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 in the scope of protection of the present invention.

Claims

1. A method for maneuvering the attitude of a small celestial body while bouncing on its surface, characterized by: The following steps are included: Step 1: Establish the detector's fixed coordinate system O on the small celestial body. B -X B Y B Z B and the dynamic equations of the bounce trajectory in the surface coordinate system O-XYZ; Step 2: Establish the attitude dynamics model and attitude kinematics model of the detector in the body coordinate system, define the error angular velocity and error quaternion of the detector, and solve the rotation matrix of the body coordinate system relative to the target coordinate system; due to the uncertainty of the rotational inertia of the detector, the rotational inertia J is divided into deterministic The uncertainty △J is divided into two parts, and the uncertainty of the moment of inertia is combined with the external interference to form the total interference suffered by the detector. That is, the total interference suffered by the detector is used to characterize the initial error caused by the uncertainty of the cube-shaped detector's own moment of inertia and the interference of the external environment when it takes off. Then, the detector bounce movement error attitude dynamics model including the total interference of the uncertainty of its own moment of inertia and the external environment disturbance is obtained. Step 3: The flight time of the cube detector during the bouncing movement is limited. A terminal sliding mode surface containing the vector exponential term of the detector attitude quaternion is constructed; a Lyapunov function is constructed to verify the terminal sliding mode surface. The finite time control principle is used to verify that the terminal sliding mode surface converges in a finite time. The terminal sliding mode surface is used to enable the cube detector to reach the target attitude in a finite time. Step 4: Based on the initial error caused by the uncertainty of the cube-shaped detector's own moment of inertia at takeoff in step 2 and the interference of the external environment, the total interference is dynamically estimated through an adaptive mechanism on the terminal sliding mode surface described in step 3, and an exponential reaching law is selected to design a finite-time stable sliding mode control law. The estimated dynamic total interference term is introduced into the finite-time stable sliding mode control law to obtain a finite-time adaptive sliding mode control law, thereby eliminating the influence of the uncertainty of the cube-shaped detector's moment of inertia and the environmental disturbance on the stability of the detector system, thereby improving the robustness of the detector attitude control system; Step 5: Substitute the cube detector finite-time adaptive sliding mode control law obtained in step 4 into the detector bouncing movement error attitude dynamics model described in step 2, which includes the uncertainty of its own rotational inertia and the total interference of external environmental disturbances, and then realize the attitude maneuvering control of the cube-shaped detector during the bouncing movement on the surface of the small celestial body within a finite time, thereby improving the robustness of the detector system and improving the attitude control accuracy and efficiency.

2. The method for maneuvering control of a small celestial body's surface bouncing movement according to claim 1, characterized in that: Step 1 is implemented as follows: Regarding the single bounce motion problem of the probe, in the fixed coordinate system of the small celestial body, the dynamic equation of the probe after take-off is expressed as Among them, r B 、v B are the position and velocity vectors of the detector, ω is the spin angular velocity of the small celestial body, and g is the gravitational acceleration vector of the small celestial body; In the surface coordinate system, the dynamic equation of the detector is: Among them, r and v are the position and velocity vectors of the detector respectively, and ρ is the position vector of the origin of the surface coordinate system relative to the center of the small celestial body. is the matrix for transforming from the body coordinate system to the surface coordinate system.

3. The method for controlling the surface bouncing movement of a small celestial body according to claim 2, wherein: Step 2 is implemented as follows: In the body coordinate system, the attitude dynamics model of the cube detector is constructed as follows: Among them, ω is the attitude angular velocity of the detector, J is the moment of inertia matrix of the detector, u is the control torque, d is the external interference torque, and the external interference torque is defined as a Gaussian white noise with bounded norm, that is, The quaternion of the detector body coordinate system relative to the inertial coordinate system is Angular velocity is ω=[ω x ω y ω z ] T , then the attitude kinematics of the detector is: Among them, q0 is the quaternion's standard part, q v is the vector part of the quaternion, and The expected quaternion of the probe during flight is q f , the desired angular velocity is ω f , define the error quaternion as q e ,have: Then the rotation matrix from the target coordinate system to the body coordinate system is: The error angular velocity of the body coordinate system relative to the target coordinate system is defined as: oh e =ω-C e oh f (8) Combining equations (4), (6), and (8), the attitude kinematic equation of the detector based on the error quaternion is: Substituting equation (8) into equation (3), the attitude dynamics model of the detector based on the error angular velocity is obtained as follows: Considering the uncertainty of the detector's moment of inertia, the moment of inertia J is divided into deterministic and uncertainty △J, namely Substituting into formula (11) we get: Among them, the uncertainty of the moment of inertia is combined with the external interference to form the total interference d e for: The total interference d received by the detector e The initial error caused by the uncertainty of the cube-shaped detector's own moment of inertia and the interference of the external environment when it takes off is characterized, and then the detector bouncing movement error attitude dynamics model including the total interference of the uncertainty of its own moment of inertia and the external environment disturbance is obtained as shown in formula (12).

4. The method for maneuvering control of a small celestial body's surface bouncing movement as claimed in claim 3, characterized in that: Step 3 is implemented as follows: The flight time of the cube detector during the bouncing movement is limited. The terminal sliding mode surface containing the vector exponential term of the detector attitude quaternion is constructed as shown in formula (13): s = ω e +ksig β (q ev ) (13) Among them, k is a positive constant, sig β (q ev )=[sig β (q e1 ) sig β (q e2 ) sig β (q e3 )] T , and sig β (q ei )=sgn(q ei )|q ei | β , i=1,2,3,0<β<1; Construct the Lyapunov function as: Derivative of the above formula (14) yields: When the detector system state reaches the sliding surface, s = 0, that is, ω = -ksgn β (q ev ), and substituting into formula (15) we get: again but Right now: Formula (17) satisfies the finite time stability theorem, thereby verifying that the terminal sliding surface converges in a finite time. Furthermore, by using the terminal sliding surface including the vector exponential term of the detector attitude quaternion as shown in formula (13), it is possible to ensure that the cube detector reaches the target attitude in a finite time.

5. The method for maneuvering control of the surface bouncing movement of a small celestial body according to claim 4, characterized in that: Step 4 is implemented as follows: Derivative the terminal sliding mode surface equation (13) on both sides including the vector exponential term of the detector attitude quaternion, and substitute equation (9) into it to obtain: Multiply both sides of equation (18) by Substituting formula (12) into the equation, we get: Selection exponential reaching law Substituting into the above formula, we get the finite-time adaptive sliding mode control law as follows: in, is the upper limit of perturbation ||d e || ∞ The estimated value of c>0 is the adaptive speed constant, ε is a positive constant; Select the Lyapunov function as: Taking the derivative, we get: Therefore, the sliding surface tends to be consistent and asymptotically stable and the system can converge to the sliding surface in a finite time.

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