Lunar surface sampling inversion presentation system based on sparse feedback

Abstract

The invention discloses a lunar surface sampling inversion presentation system based on sparse feedback, and the system comprises a far-end sensing subsystem which is used for collecting the execution environment of a lunar surface sampling task and the state of a spacecraft, carrying out the quantification, mapping coding, sampling and assembly processing of the collected data, and outputting a telemetering data frame; the measurement and control base station is used for receiving and forwarding telemetry data frames; and the near-end inversion presentation subsystem is used for carrying out channel equalization, decoding, state restoration reconstruction and presentation processing on the received telemetry data frame to obtain a multi-dimensional presentation result. According to the method, the problem that in the autonomous task execution process of the spacecraft, due to spacecraft downlink communication link condition constraint, low communication bandwidth and multi-path propagation existing in a channel, inter-symbol interference, frame error, frame disorder and frame loss are caused, and the task execution state of the spacecraft is difficult to timely and fully present by the ground is solved; and ground operators can accurately make decisions and provide necessary control support.

Description

Technical Field

[0001] The present invention belongs to the field of spacecraft technology, and in particular relates to a lunar surface sampling inversion presentation system based on sparse feedback. Background Art

[0002] Unlike low-Earth orbit satellites and conventional deep space exploration missions, when the extraterrestrial body sampling mission is executed, due to the extraterrestrial body’s long distance from the Earth and the influence of the communication link environment, the spacecraft on the Earth that performs the sampling mission on the surface of the extraterrestrial body has low communication bandwidth, high data error rate and easy data frame loss when exchanging uplink and downlink information. To avoid this problem, the spacecraft has enhanced its autonomous capability, which can complete the sampling mission with the support of a small amount of delayed uplink remote control, while compressing and limiting the downlink telemetry, and using sparse telemetry to feedback the mission execution status of the spacecraft. However, the unmanned sampling mission of extraterrestrial bodies faces a) complex environment and great differences from the test environment carried out during the design and development of the spacecraft; b) the sampling mechanism needs to couple with the sampling target during the sampling mission, and is also affected by energy, heat, light and the interference of the sampling mechanism with the body motion, making the sampling mission execution control difficult; c) due to the high reliability requirements of mission execution and the constraints of spacecraft storage and computing power, the spacecraft’s autonomous mission execution and decision-making capabilities are limited.

[0003] In summary, on the one hand, due to the influence of communication conditions, the frequency and amount of data exchange between the ground and the spacecraft are limited, and the spacecraft needs to perform sampling tasks autonomously. On the other hand, due to the limited autonomous capabilities of the spacecraft, ground personnel are still needed to make decisions and provide support. Ground personnel need to fully understand the current operating status of the spacecraft in order to make correct decisions and provide accurate control support for the spacecraft. There is a contradiction between the two requirements. Summary of the invention

[0004] The technology of the present invention solves the problem: Overcoming the shortcomings of the prior art, providing a lunar sampling inversion presentation system based on sparse feedback, aiming to solve the problem that during the spacecraft's autonomous mission execution, due to the constraints of the spacecraft's downlink communication link conditions, low communication bandwidth, and multipath propagation in the channel causing inter-code interference, there are wrong frames, chaotic frames and lost frames, making it difficult for the ground to present the spacecraft's mission execution status in a timely and sufficient manner, supporting ground control personnel to make accurate decisions and provide necessary control support.

[0005] In order to solve the above technical problems, the present invention discloses a lunar surface sampling inversion presentation system based on sparse feedback, comprising:

[0006] The remote sensing subsystem is used to collect the lunar sampling mission execution environment and the spacecraft's own status, and quantize, map, encode, sample, assemble and process the collected data to output telemetry data frames;

[0007] The measurement and control base station is used to receive the telemetry data frames transmitted by the remote sensing subsystem and forward them to the near-end inversion and presentation subsystem;

[0008] The proximal inversion and presentation subsystem is used to receive the telemetry data frames forwarded by each measurement and control base station, and perform channel equalization, decoding, state restoration and reconstruction, and presentation processing on the telemetry data frames forwarded by each measurement and control base station, so as to obtain multi-dimensional presentation results that can support ground personnel to monitor the status of spacecraft performing sampling missions on extraterrestrial bodies.

[0009] In the above-mentioned lunar surface sampling inversion and presentation system based on sparse feedback, the remote sensing subsystem is deployed on the spacecraft, and the measurement and control base station and the proximal inversion and presentation subsystem are deployed on the ground.

[0010] In the above-mentioned lunar surface sampling inversion and presentation system based on sparse feedback, the remote sensing subsystem includes:

[0011] Sensors, used to sense the mission execution environment and the spacecraft's own status;

[0012] The mission execution status acquisition and quantification module is used to control the sensor to perceive the mission execution environment and the spacecraft's own status after the spacecraft lands on the moon and reaches the designated mission execution area, and to collect and quantify the sensor's perception information to obtain an N-dimensional data set vector S moon (t);

[0013] Data mapping encoding module is used to encode the N-dimensional data set vector S moon (t) Perform data mapping and coding compression to obtain an M-dimensional state mapping vector S′ moon (t) = F(S moon (t)); where F represents the data mapping and encoding compression function, M< <N;

[0014] Discrete random sampling module, used to map the M-dimensional state vector S′ moon (t) Perform random sampling to obtain a sparse state vector x[n] = S′ moon [n×(T s ±δ)]; where T s represents the random sampling period, δ represents the random disturbance;

[0015] The module for assembling sparse state data frames is used to simulate the computer telemetry organization method and strategy on the spacecraft, pack and assemble the sparse state vector x[n] to obtain the telemetry data frame Fx=Tmh+x[n]; wherein Tmh represents the telemetry protocol encapsulation format data word.

[0016] In the above-mentioned lunar surface sampling inversion presentation system based on sparse feedback, the sensors include: cameras, temperature sensors and mechanical sensors.

[0017] In the above-mentioned lunar surface sampling inversion and presentation system based on sparse feedback, the telemetry data frame output by the remote sensing subsystem is Fx. Affected by the bit error rate of the deep space communication link, the telemetry data frames actually received by each measurement and control base station are Fx′1, Fx′2, Fx′3….

[0018] In the above-mentioned lunar surface sampling inversion and presentation system based on sparse feedback, the proximal inversion and presentation subsystem includes:

[0019] The data channel equalization module is used to synchronously receive the telemetry data frames Fx′1, Fx′2, Fx′3… forwarded by each measurement and control base station by using the time stamp information in the data; perform channel equalization processing on the received telemetry data frames Fx′1, Fx′2, Fx′3… forwarded by each measurement and control base station to obtain an estimate y′(t) of the sparse state vector matrix;

[0020] The data decoding and state reconstruction module is used to reversely invert y′(t) y(t) = F using the data set mapping encoding method. -1 (y′(t)); According to the inversion result y(t) at the current moment and the inversion result y(t-1) at the previous moment, the telemetry change Δ(t)=y(t)-y(t-1) is obtained; according to the telemetry change Δ(t), the state is restored and reconstructed to obtain the reconstruction result S rebulid (t);

[0021] The sampling task executes the restoration function module to reconstruct the result S rebulid (t) Differentiation processing The differential processing result Γ(t) is used as the final state restoration and reconstruction result;

[0022] The visualization function module is used to realize the visualization of the final state restoration and reconstruction result Γ(t) in three dimensions, and obtain a multi-dimensional presentation result that can support ground personnel to monitor the state of the spacecraft performing sampling missions on extraterrestrial bodies.

[0023] In the above-mentioned lunar sampling inversion presentation system based on sparse feedback, when the data channel equalization module performs channel equalization processing on the telemetry data frames Fx′1, Fx′2, Fx′3… received and forwarded by each measurement and control base station to obtain the estimation y′(t) of the sparse state vector matrix, it includes:

[0024] Unpack the telemetry data frames Fx′1, Fx′2, Fx′3…, and obtain a sparse state vector matrix X(t′)={Fx′1-Tmh, Fx′2-Tmh, Fx′3-Tmh,…};

[0025] Substitute X(t′) into the linear equation y′(t)=X(t′)×v+φ to obtain the estimate y′(t) of the sparse state vector matrix; where v and φ represent the evaluation parameters of the measurement and control base station for the quality of received and forwarded data, respectively.

[0026] In the above-mentioned lunar sampling inversion presentation system based on sparse feedback, the data decoding and state reconstruction module obtains the reconstruction result S through the following formula: rebulid (t):

[0027] S rebulid (t) = Θ e (Δ(t))+Φ s (Δ(t))+S rebulid (t-1)

[0028] Among them, S rebulid (t-1) represents the reconstruction result of the previous moment, Θ e (Δ(t)) represents the a priori simulation of the task execution environment of the telemetry change Δ(t), Φ s (Δ(t)) represents the spacecraft simulation of the telemetry change Δ(t).

[0029] The present invention has the following advantages:

[0030] The present invention discloses a lunar surface sampling inversion presentation system based on sparse feedback, which comprehensively and uniformly plans the onboard and ground systems of the spacecraft, and realizes high-fidelity state reproduction of the sampling mission on the surface of extraterrestrial bodies through data set mapping coding, data balancing, inverse data set mapping coding and differential data model driving. Through the visual presentation, the user can efficiently and accurately grasp the current execution status of the spacecraft sampling mission and deal with the emergency status in time. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a block diagram of a lunar surface sampling inversion and presentation system based on sparse feedback in an embodiment of the present invention;

[0032] Figure 2 It is a schematic diagram of the calling relationship of each main module in an embodiment of the present invention. DETAILED DESCRIPTION

[0033] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments disclosed in the present invention will be further described in detail below with reference to the accompanying drawings.

[0034] One of the core ideas of the present invention is to provide a lunar sampling inversion presentation system based on sparse feedback. Under the conditions of deep space communication links, it can reconstruct and balance the spacecraft status data according to the sparse characteristics of the channel, and use the existing prior knowledge to fully and accurately present the spacecraft status, support ground personnel to monitor the status of the spacecraft performing sampling missions on extraterrestrial bodies, and intervene and control in time to deal with difficulties and emergencies in the execution of the mission.

[0035] Reference Figure 1 In this embodiment, the lunar sampling inversion and presentation system based on sparse feedback includes: a remote sensing subsystem, a measurement and control base station, and a near-end inversion and presentation subsystem. The remote sensing subsystem is deployed on the spacecraft, and the measurement and control base station and the near-end inversion and presentation subsystem are deployed on the ground.

[0036] The remote sensing subsystem is used to collect information about the lunar sampling mission execution environment and the spacecraft's own status, and to quantify, map, encode, sample, and assemble the collected data to output telemetry data frames.

[0037] In this embodiment, the remote sensing subsystem mainly includes:

[0038] Sensors are used to sense the mission execution environment and the spacecraft's own status. Sensors include but are not limited to: cameras, temperature sensors, and mechanical sensors.

[0039] The mission execution status acquisition and quantification module is used to control the sensor to perceive the mission execution environment and the spacecraft's own status after the spacecraft lands on the moon and reaches the designated mission execution area, and to collect and quantify the sensor's perception information to obtain an N-dimensional data set vector S moon (t).

[0040] Data mapping encoding module is used to encode the N-dimensional data set vector S moon (t) Perform data mapping and coding compression to obtain an M-dimensional state mapping vector S′ moon (t) = F(S moon (t)). Where F represents the data mapping and encoding compression function, M< <N。

[0041] Discrete random sampling module, used to map the M-dimensional state vector S′ moon (t) Perform random sampling to obtain a sparse state vector x[n] = S′ moon [n×(T s ±δ)], further sparse the data density and reduce the data volume. Among them, T s represents the random sampling period, and δ represents the random disturbance.

[0042] The module for assembling sparse state data frames is used to simulate the computer telemetry organization method and strategy on the spacecraft, pack and assemble the sparse state vector x[n] to obtain the telemetry data frame Fx=Tmh+x[n]; wherein Tmh represents the telemetry protocol encapsulation format data word.

[0043] The measurement and control base station is used to receive the telemetry data frames transmitted by the remote sensing subsystem and forward them to the near-end inversion and presentation subsystem.

[0044] In this embodiment, as mentioned above, the telemetry data frame output by the remote sensing subsystem is Fx. However, affected by the bit error rate of the deep space communication link, the telemetry data frames actually received by each measurement and control base station are Fx′1, Fx′2, Fx′3….

[0045] The proximal inversion and presentation subsystem is used to receive the telemetry data frames forwarded by each measurement and control base station, and perform channel equalization, decoding, state restoration and reconstruction, and presentation processing on the telemetry data frames forwarded by each measurement and control base station, so as to obtain multi-dimensional presentation results that can support ground personnel to monitor the status of spacecraft performing sampling missions on extraterrestrial bodies.

[0046] In this embodiment, the proximal inversion presentation subsystem mainly includes:

[0047] The data channel equalization module is used to synchronously receive the telemetry data frames Fx′1, Fx′2, Fx′3… forwarded by each measurement and control base station by using the time stamp information in the data; perform channel equalization processing on the telemetry data frames Fx′1, Fx′2, Fx′3… received and forwarded by each measurement and control base station to obtain the estimation y′(t) of the sparse state vector matrix. The specific implementation of the channel equalization processing is as follows: unpack the telemetry data frames Fx′1, Fx′2, Fx′3… to obtain the sparse state vector matrix X(t′)={Fx′1-Tmh, Fx′2-Tmh, Fx′3-Tmh,…}; substitute X(t′) into the solution of the linear equation y′(t)=X(t′)×v+φ, and solve to obtain the estimation y′(t) of the sparse state vector matrix; wherein v and φ respectively represent the evaluation parameters of the measurement and control base station for the quality of received and forwarded data. The data channel equalization module is configured with a mapping knowledge dictionary function. By using the time stamp field in the synchronized data to retrieve the mapping knowledge dictionary, the data is redundancy eliminated and estimated, thereby eliminating the delay effect caused by the deep space communication link.

[0048] The data decoding and state reconstruction module is used to reversely invert y′(t) y(t) = F using the data set mapping encoding method. -1 (y′(t)); According to the inversion result y(t) at the current moment and the inversion result y(t-1) at the previous moment, the telemetry change Δ(t)=y(t)-y(t-1) is obtained; according to the telemetry change Δ(t), the state is restored and reconstructed to obtain the reconstruction result Srebulid (t). Where S rebulid (t) = Θ e (Δ(t))+Φ s (Δ(t))+S rebulid (t-1), S rebulid (t-1) represents the reconstruction result of the previous moment, Θ e (Δ(t)) represents the a priori simulation of the task execution environment of the telemetry change Δ(t), Φ s (Δ(t)) represents the spacecraft simulation of the telemetry change Δ(t). The data decoding and state reconstruction module performs reverse inversion on the acquired data, accumulates it with the prior spacecraft model and the prior mission execution environment model, and generates the current data set for the mission execution environment and the spacecraft's own state.

[0049] The sampling task executes the restoration function module to reconstruct the result S rebulid (t) Differentiation processing The differential processing result Γ(t) is used as the final state restoration and reconstruction result.

[0050] The visualization function module is used to visualize the final state restoration and reconstruction result Γ(t) in three dimensions, and obtain a multi-dimensional presentation result that can support ground personnel to monitor the state of the spacecraft performing sampling missions on extraterrestrial bodies. Based on the multi-dimensional presentation results, users can efficiently and accurately grasp the current state of the spacecraft's sampling mission execution and deal with emergencies in a timely manner.

[0051] The data set mapping encoding method of the present invention is based on dividing the spacecraft upsampling task steps into several autonomous execution modules. A single autonomous execution module (taking module 1 as an example) is defined by the following rules:

[0052]

[0053] Table 1, Autonomous execution module definition table

[0054] Several autonomous execution modules are initially designed on the spacecraft, and these autonomous execution modules are dynamically combined and called. The calling relationship is as follows: Figure 2As shown. After confirming the sampling strategy that needs to be carried out, the autonomous execution module combination relational instructions that need to be called are injected into the spacecraft uplink, and the execution is started. The spacecraft calls these modules in sequence and sends control instructions to each sampling execution component according to the execution action specified by the module. At the same time, it collects the status feedback collected by each sensor to determine whether the current control action has been completed and whether the next action can be executed. It can be seen from the above that the current execution module number and the execution step sequence number can be used as a mapping index for the current task execution status. At the same time, these two parameters have good data compressibility as slow variables, which can effectively reduce the amount of downlink data. After the data is transmitted to the ground, since multiple measurement and control base stations simultaneously receive the data and forward it to the ground part of the system described in the present invention, the system needs to perform data balancing after receiving the data, eliminate data errors, redundancy and misordering, and synchronize the time system with the detector.

[0055] 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.

[0056] The contents not described in detail in the specification of the present invention belong to the common knowledge of the professionals in this field.

Claims

1. A lunar surface sampling inversion presentation system based on sparse feedback, characterized in that: include: The remote sensing subsystem is used to collect the lunar sampling mission execution environment and the spacecraft's own status, and quantize, map, encode, sample, assemble and process the collected data to output telemetry data frames; The measurement and control base station is used to receive the telemetry data frames transmitted by the remote sensing subsystem and forward them to the near-end inversion and presentation subsystem; The proximal inversion and presentation subsystem is used to receive the telemetry data frames forwarded by each measurement and control base station, and perform channel equalization, decoding, state restoration and reconstruction, and presentation processing on the telemetry data frames forwarded by each measurement and control base station, so as to obtain multi-dimensional presentation results that can support ground personnel to monitor the status of spacecraft performing sampling missions on extraterrestrial bodies.

2. The lunar sampling inversion and presentation system based on sparse feedback according to claim 1, characterized in that: The remote sensing subsystem is deployed on the spacecraft, and the measurement and control base station and the proximal inversion and presentation subsystem are deployed on the ground.

3. The lunar sampling inversion and presentation system based on sparse feedback according to claim 1, characterized in that: Remote sensing subsystem, including: Sensors, used to sense the mission execution environment and the spacecraft's own status; The mission execution status acquisition and quantification module is used to control the sensor to perceive the mission execution environment and the spacecraft's own status after the spacecraft lands on the moon and reaches the designated mission execution area, and to collect and quantify the sensor's perception information to obtain an N-dimensional data set vector S moon (t); Data mapping encoding module is used to encode the N-dimensional data set vector S moon (t) Perform data mapping and coding compression to obtain an M-dimensional state mapping vector S′ moon (t) = F(S moon (t)); where F represents the data mapping and encoding compression function, M< <N; Discrete random sampling module, used to map the M-dimensional state vector S′ moon (t) Perform random sampling to obtain a sparse state vector x[n] = S′ moon [n×(T s ±δ)]; where T s represents the random sampling period, δ represents the random disturbance; The module for assembling sparse state data frames is used to simulate the computer telemetry organization method and strategy on the spacecraft, pack and assemble the sparse state vector x[n] to obtain the telemetry data frame Fx=Tmh+x[n]; wherein Tmh represents the telemetry protocol encapsulation format data word.

4. The lunar sampling inversion and presentation system based on sparse feedback according to claim 3 is characterized in that: Sensors, including: cameras, temperature sensors, and mechanical sensors.

5. The lunar sampling inversion and presentation system based on sparse feedback according to claim 3 is characterized in that: The telemetry data frame output by the remote sensing subsystem is Fx. Affected by the bit error rate of the deep space communication link, the telemetry data frames actually received by each measurement and control base station are Fx1′, Fx2′, Fx3′….

6. The lunar sampling inversion and presentation system based on sparse feedback according to claim 5, characterized in that: The proximal inversion presentation subsystem includes: The data channel equalization module is used to synchronously receive the telemetry data frames Fx1′, Fx2′, Fx3′… forwarded by each measurement and control base station by using the time stamp information in the data; perform channel equalization processing on the received telemetry data frames Fx1′, Fx2′, Fx3′… forwarded by each measurement and control base station to obtain an estimate y′(t) of the sparse state vector matrix; The data decoding and state reconstruction module is used to reversely invert y′(t) y(t) = F using the data set mapping encoding method. -1 (y′(t)); According to the inversion result y(t) at the current moment and the inversion result y(t-1) at the previous moment, the telemetry change Δ(t)=y(t)-y(t-1) is obtained; according to the telemetry change Δ(t), the state is restored and reconstructed to obtain the reconstruction result S rebulid (t); The sampling task executes the restoration function module to reconstruct the result S rebulid (t) Differentiation processing The differential processing result Γ(t) is used as the final state restoration and reconstruction result; The visualization function module is used to realize the visualization of the final state restoration and reconstruction result Γ(t) in three dimensions, and obtain a multi-dimensional presentation result that can support ground personnel to monitor the state of the spacecraft performing sampling missions on extraterrestrial bodies.

7. The lunar sampling inversion and presentation system based on sparse feedback according to claim 6, characterized in that: The data channel equalization module performs channel equalization processing on the telemetry data frames Fx1′, Fx2′, Fx3′… received and forwarded by each measurement and control base station to obtain an estimate y′(t) of the sparse state vector matrix, including: Unpack the telemetry data frames Fx1′, Fx2′, Fx3′…, and obtain the sparse state vector matrix X(t′)={Fx1′-Tmh, Fx2′-Tmh, Fx3′-Tmh,…}; Substitute X(t′) into the linear equation y′(t)=X(t′)×v+φ to obtain the estimate y′(t) of the sparse state vector matrix; where v and φ represent the evaluation parameters of the measurement and control base station for the quality of received and forwarded data, respectively.

8. The lunar sampling inversion and presentation system based on sparse feedback according to claim 7, characterized in that: The data decoding and state reconstruction module obtains the reconstruction result S through the following formula: rebulid (t): S rebulid (t)=Θ e (Δ(t))+Φ s (Δ(t))+S rebulid (t-1) Among them, S rebulid (t-1) represents the reconstruction result of the previous moment, Θ e (Δ(t)) represents the a priori simulation of the task execution environment of the telemetry change Δ(t), Φ s (Δ(t)) represents the spacecraft simulation of the telemetry change Δ(t).

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