Moon car polar region path planning method and device based on dynamic light condition analysis

Abstract

The application provides a lunar rover polar region path planning method and device based on dynamic light condition analysis, and relates to the technical field of spaceflight measurement and control. The method comprises the following steps: generating a forward and reverse light safety corridor according to a light prediction file and preset information; determining a normalized light energy availability index parameter according to the forward and reverse light safety corridor and the light prediction file, and calculating the normalized light energy availability index parameter to obtain a normalized light energy availability index; determining a shadow coverage cost according to the normalized light energy availability index, and superimposing the shadow coverage cost on the forward and reverse light safety corridor to obtain a light cost map; and performing lunar rover polar region path planning according to the light cost map and a pre-acquired terrain through cost map. The device executes the above method. The method and device provided in the application embodiment significantly improve the global path planning capability of the lunar rover in extreme terrain, dynamic light and a large unknown area.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of spaceflight TT&C technology, in particular to a lunar rover polar region path planning method and device based on dynamic light condition analysis. BACKGROUND

[0002] As a key infrastructure for planetary surface exploration, the lunar rover breaks through the space limitation of static detectors and is a key research direction in lunar exploration missions. The path planning technology of the lunar rover is a key support in the patrol detection mission of the lunar rover, which builds a basic framework for mobile detection through core functions such as danger area avoidance, lunar surface efficient patrol, and target point safe navigation. The algorithm accuracy and real-time performance of the technology directly determine the task execution efficiency and the safety level of the lunar rover body, and as a prerequisite for realizing wide-area scientific exploration, the optimization degree has become an important technical index for measuring the operation ability of the lunar rover.

[0003] On the other hand, the lunar polar region, such as the lunar south polar region, not only preserves key information of the evolution of the solar system, but also has a unique advantage in establishing a long-term manned base, and has become a core target area for future deep space exploration. The lunar south polar region has a relatively rapid changing dynamic light shadow area formed by the low solar elevation angle and the terrain fluctuation, and the spatio-temporal distribution presents a significant nonlinear time-varying characteristic, which constitutes a multidimensional constraint for the path planning of the lunar rover. The periodic change of the solar elevation angle and the azimuth angle causes the rapid and continuous migration of the shadow boundary, resulting in dynamic changes in the light condition, forcing the path planning to optimize the light condition and the terrain element simultaneously. More complexly, the topological structure formed by the interlaced permanent shadow area and transient light area causes the traditional path planning method based on static digital elevation model to fail. SUMMARY

[0004] In view of the problems in the prior art, the present application provides a lunar rover polar region path planning method and device based on dynamic light condition analysis, which can at least partially solve the problems in the prior art.

[0005] In one aspect, the present application provides a lunar rover polar region path planning method based on dynamic light condition analysis, comprising:

[0006] generating a forward and reverse light safety corridor according to a light prediction file and preset information;

[0007] determining a normalized light energy availability index parameter according to the forward and reverse light safety corridor and the light prediction file, and calculating a normalized light energy availability index according to the normalized light energy availability index parameter;

[0008] determining a shadow coverage cost according to the normalized light energy availability index, and superimposing the shadow coverage cost to the forward and reverse light safety corridor to obtain a light cost map;

[0009] Carrying out polar region path planning of the lunar rover according to the light cost map and a pre-acquired terrain through a cost map.

[0010] The pre-setting information includes a pre-set moving time interval, a pre-set single-step moving distance and a pre-set forward and reverse time increment parameter; correspondingly, the generating of the forward and reverse light safety corridor according to the light forecast file and the pre-setting information includes:

[0011] reading the light forecast file to obtain a central time of a moving starting point of the lunar rover, taking the central time as a time reference point, and determining a light safety window model according to the pre-set forward and reverse time increment parameter;

[0012] generating the forward and reverse light safety corridor according to the light safety window model, the pre-set single-step moving distance and the pre-set moving time interval.

[0013] The determining of the normalized light energy availability index parameter according to the forward and reverse light safety corridor and the light forecast file includes:

[0014] determining light durations corresponding to respective levels of the forward and reverse light safety corridor, with the central time as a time starting point;

[0015] calculating the normalized light energy availability index parameter according to the light durations and a light forecast file time range of the light forecast file.

[0016] The calculating of the normalized light energy availability index according to the normalized light energy availability index parameter includes:

[0017] The normalized light energy availability index is calculated according to the following formula:

[0018] S(x,y)=Tm / (t_max-t_min);

[0019] wherein S(x,y) is the normalized light energy availability index, Tm is the light duration, t_max is a maximum value in the light forecast file time range, and t_min is a minimum value in the light forecast file time range.

[0020] The determining of the shadow coverage cost according to the normalized light energy availability index includes:

[0021] The shadow coverage cost is determined as a calculation result of subtracting the normalized light energy availability index from 1.

[0022] The lunar rover polar region path planning according to the light cost map and a pre-acquired terrain passing cost map comprises the following steps:

[0023] An environment cost map is generated according to the light cost map and the terrain passing cost map;

[0024] A heuristic search and path smoothing process are performed on the environment cost map to obtain a lunar rover polar region path planning result.

[0025] In one aspect, the application provides a lunar rover polar region path planning device based on dynamic light condition analysis, which comprises the following steps:

[0026] A generation unit is configured to generate a forward and reverse light safety corridor according to a light forecast file and preset information;

[0027] An acquisition unit is configured to determine a normalized light energy availability index parameter according to the forward and reverse light safety corridor and the light forecast file, and calculate a normalized light energy availability index according to the normalized light energy availability index parameter;

[0028] A superposition unit is configured to determine a shadow coverage cost according to the normalized light energy availability index, and superimpose the shadow coverage cost on the forward and reverse light safety corridor to obtain a light cost map;

[0029] A planning unit is configured to perform lunar rover polar region path planning according to the light cost map and a pre-acquired terrain passing cost map.

[0030] In another aspect, the application provides a computer device, which comprises a memory, a processor and a computer program stored in the memory and executable on the processor, and the processor implements the following method when executing the computer program:

[0031] A forward and reverse light safety corridor is generated according to a light forecast file and preset information;

[0032] A normalized light energy availability index parameter is determined according to the forward and reverse light safety corridor and the light forecast file, and a normalized light energy availability index is calculated according to the normalized light energy availability index parameter;

[0033] A shadow coverage cost is determined according to the normalized light energy availability index, and the shadow coverage cost is superimposed on the forward and reverse light safety corridor to obtain a light cost map;

[0034] Lunar rover polar region path planning is performed according to the light cost map and a pre-acquired terrain passing cost map.

[0035] The application provides a computer readable storage medium, which comprises:

[0036] The computer readable storage medium stores a computer program, and the computer program is executed by a processor to implement the following method:

[0037] generate a positive and negative light safety corridor according to the light prediction file and preset information;

[0038] determine a normalized light energy availability index parameter according to the positive and negative light safety corridor and the light prediction file, and calculate a normalized light energy availability index according to the normalized light energy availability index parameter;

[0039] determine a shadow coverage cost according to the normalized light energy availability index, and superimpose the shadow coverage cost to the positive and negative light safety corridor to obtain a light cost map;

[0040] perform polar region path planning of the lunar rover according to the light cost map and a pre-acquired terrain through cost map.

[0041] The embodiment of the present application also provides a computer program product, which comprises a computer program, and the computer program is executed by a processor to implement the following method:

[0042] generate a positive and negative light safety corridor according to the light prediction file and preset information;

[0043] determine a normalized light energy availability index parameter according to the positive and negative light safety corridor and the light prediction file, and calculate a normalized light energy availability index according to the normalized light energy availability index parameter;

[0044] determine a shadow coverage cost according to the normalized light energy availability index, and superimpose the shadow coverage cost to the positive and negative light safety corridor to obtain a light cost map;

[0045] perform polar region path planning of the lunar rover according to the light cost map and a pre-acquired terrain through cost map.

[0046] The lunar rover polar region path planning method and device based on dynamic light condition analysis provided by the embodiment of the present application generate a forward and reverse light safety corridor according to a light forecast file and preset information; determine a normalized light energy availability index parameter according to the forward and reverse light safety corridor and the light forecast file, and calculate a normalized light energy availability index according to the normalized light energy availability index parameter; determine a shadow coverage cost according to the normalized light energy availability index, and superimpose the shadow coverage cost to the forward and reverse light safety corridor to obtain a light cost map; and perform lunar rover polar region path planning according to the light cost map and a pre-acquired terrain through cost map, which realizes a technical breakthrough of dynamic light condition adaptation and multi-constraint collaborative optimization in a long-period exploration task under a complex lunar surface environment, and significantly improves the global path planning capability of the lunar rover in an extreme terrain, dynamic light and a large unknown area. BRIEF DESCRIPTION OF DRAWINGS

[0047] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from these drawings without any creative effort. In the drawings:

[0048] Figure 1 is a flowchart of the lunar rover polar region path planning method based on dynamic light condition analysis provided by an embodiment of the present application.

[0049] Figure 2 is a flowchart of the lunar rover polar region path planning method based on dynamic light condition analysis provided by another embodiment of the present application.

[0050] Figure 3 is a flowchart of the lunar rover polar region path planning method based on dynamic light condition analysis provided by another embodiment of the present application.

[0051] Figure 4 is a schematic diagram of a light safety window model provided by an embodiment of the present application.

[0052] Figure 5 is a schematic diagram of a forward and reverse light safety corridor provided by an embodiment of the present application.

[0053] Figure 6 is a flowchart of the lunar rover polar region path planning method based on dynamic light condition analysis provided by another embodiment of the present application.

[0054] Figure 7 is a structural schematic diagram of the lunar rover polar region path planning device based on dynamic light condition analysis provided by an embodiment of the present application.

[0055] Figure 8 The computer device entity structure schematic diagram provided for the embodiment of the present application. DETAILED DESCRIPTION

[0056] In order to make the purpose, technical scheme and advantages of the embodiment of the present application more clear and obvious, the embodiment of the present application is further described in detail below in combination with the drawings. Herein, the illustrative embodiment of the present application and the description thereof are used to explain the present application, but not as a limitation of the present application. It should be noted that, in the case of no conflict, the embodiment in the present application and the features in the embodiment can be combined with each other at will.

[0057] Path planning, as a core link in the lunar rover exploration mission, is a key technical basis for ensuring the safe and efficient execution of scientific exploration missions by the lunar rover. Under the extreme lunar surface environment, the path planning algorithm needs to cope with multiple challenges such as complex terrain obstacle avoidance, passability analysis, dynamic light condition changes, etc., and its performance directly affects the man-machine cooperation efficiency of the ground remote operation system and the real-time response ability of the vehicle-mounted system. In the past lunar surface exploration missions, the ground center mainly uses the method of "environmental cost map + path search" to realize the path planning of the lunar rover. The specific implementation technical scheme is as shown in Figure 1

[0058] Firstly, based on the digital elevation map (DEM) of the lunar surface, the slope, slope direction and roughness of each point in the map are calculated respectively, and combined with the passability of the lunar rover (the ability to climb and the ability to cross the steps), the non-passable area is identified as an obstacle area.

[0059] Secondly, the passing cost of the obstacle area is defined as infinity; for the non-obstacle area, the slope passing cost and the roughness passing cost are calculated respectively.

[0060] Thirdly, the above costs are weighted and superimposed to form a terrain passing cost map.

[0061] Fourthly, combined with the light prediction file, the light conditions of each point in the DEM map range at the current time are obtained, and the light cost of the area with light is defined as 0, and the light cost of the area without light is defined as infinity.

[0062] Fifthly, the terrain passing cost and the light cost map are superimposed to generate an environmental cost map.

[0063] Sixthly, the passable path is obtained by heuristic search.

[0064] Seventhly, the path is smoothed by curve fitting.

[0065] ​The above method has passed engineering verification in early lunar exploration missions, and provides effective foundation support for path planning of the lunar rover. However, in-depth analysis shows that the method has theoretical and engineering limitations in modeling of light conditions, and the specific reasons are as follows.

[0066] Problem analysis: the above method adopts a discretization processing strategy, which simplifies the continuous time-varying light intensity into a static binary condition (the light area cost at the current time is 0, and the shadow area is infinite). This simplification mechanism degrades the dynamic time-varying constraint into a fixed constraint, resulting in non-physical transitions of the cost function. This over-simplification not only weakens the dynamic space-time coupling characteristics of the light constraint, but also causes non-continuous jumps in the cost function during path search, affecting the global optimization performance of the planning algorithm.

[0067] In engineering practice, the application efficiency of the simplified model presents significant spatial heterogeneity and temporal limitation: when the lunar rover runs near the equator in a flat impact crater, due to the high solar elevation angle and low terrain shielding rate, the discretization processing can save certain computing power by sacrificing shadow migration accuracy, meeting the task requirements of short-term exploration and detection. However, in high-latitude complex canyon areas, the solar elevation angle is low, and the dynamic shadow change rate caused by terrain undulation is high, resulting in failure of the simplified model, and significantly restricting the path planning capability of the ground center in a large range and long distance in the lunar exploration mission.

[0068] Figure 2 is a flowchart of a lunar rover polar region path planning method based on dynamic light condition analysis provided by an embodiment of the present application, as shown in Figure 2 The lunar rover polar region path planning method based on dynamic light condition analysis provided by the embodiment of the present application comprises the following steps.

[0069] Step S1: generating forward and reverse light safety corridors according to light prediction files and pre-set information.

[0070] Step S2: determining a normalized light energy availability index parameter according to the forward and reverse light safety corridors and the light prediction files, and calculating a normalized light energy availability index according to the normalized light energy availability index parameter.

[0071] Step S3: determining a shadow coverage cost according to the normalized light energy availability index, and superimposing the shadow coverage cost on the forward and reverse light safety corridors to obtain a light cost map.

[0072] Step S4: performing lunar rover polar region path planning according to the light cost map and a pre-acquired terrain passing cost map.

[0073] In the step S1, the device generates the forward and reverse light safety corridor according to the light forecast file and the preset information. The device can be a computer device for executing the method. In the technical solution of the present application, the acquisition, storage, use, processing, etc. of data comply with relevant regulations. The ground control center constructs a high-precision long-term light forecast file based on a regional digital elevation map (DEM), combined with the dynamic change law of the solar elevation angle and the azimuth angle, through a three-dimensional light simulation algorithm. The file not only contains the light intensity of each coordinate point at different times, but also accurately records the shadow duration and light change caused by terrain obstruction.

[0074] The preset information includes a preset moving time interval, a preset single-step moving distance, and a preset forward and reverse time increment parameter. Correspondingly, the generation of the forward and reverse light safety corridor according to the light forecast file and the preset information includes:

[0075] The center time of the rover moving starting point is obtained by reading the light forecast file. The light safety window model is determined according to the preset forward and reverse time increment parameters, taking the center time as a time reference point. As shown in Figure 3 The preset moving time interval corresponds to the moving time interval dT, the preset single-step moving distance corresponds to the single-step moving distance dL, and the preset forward and reverse time increment parameters correspond to the forward time increment parameter dt1 and the reverse time increment parameter dt2. As shown in Figure 4 The light safety window model is shown in

[0076] Taking the preset moving time interval as an example, the moving time interval default value can be set, or it can be set by manual setting. The intervention time of manual setting can be determined according to manual experience.

[0077] The light safety window model in the rover path planning takes the time reference point T0 as the core of spatiotemporal coupling analysis, constructs the dynamic evaluation interval [T0-dt2, T0+dt1] through the forward and reverse time increment parameters dt1 / dt2, which not only represents the light characteristics at the current time, but also establishes a continuous time domain containing historical light change patterns and future light evolution trends through forward deduction and reverse tracing mechanisms.

[0078] In the time-space coupling decision framework of lunar rover path planning, the positive and negative time increment parameters dt1 / dt2 adopt a human-machine collaborative dynamic configuration mechanism, and their assignment process is realized through an interactive interface. The operator sets the initial value range based on task priority and equipment state. Further analysis of the characteristics of dt1 and dt2 is as follows:

[0079] 1. In the time-space constraint relaxation scenario of lunar rover path planning, when the positive and negative time increment parameters dt1 / dt2 are set to zero, the system will degenerate into an instantaneous state-based illumination constraint model. At this time, the time dimension is compressed to a single time T0, resulting in the maximum spatial expansion of the confidence domain boundary of the safe corridor. The coverage range is directly determined by the illumination conditions and terrain shielding at time T0. This time-space convergence state essentially eliminates the coupled analysis of historical illumination change patterns and future change evolution trends, making the geometric characteristics of the safe corridor degenerate into the instantaneous feasible region under traditional two-dimensional projection. The advantage is to maximize the real-time performance of path planning, but the safety redundancy is significantly reduced due to the uncertainty of shadow boundary caused by the dynamic shift of solar azimuth angle.

[0080] 2. In the extreme constraint scenario of lunar rover path planning, when the positive and negative time increment parameters dt1 / dt2 tend to infinity or exceed the time boundary of the illumination forecast file, the system will enter the full-time domain tight constraint mode. At this time, the confidence boundary of the safe corridor collapses in space - its generation logic is driven by the time-space full coupling analysis of solar elevation angle and terrain shielding, requiring the target area to continuously meet multi-dimensional constraint conditions on the complete time axis of the illumination forecast file (from the initial time t_min to the terminal time t_max). This ultra-conservative mode may lead to the inability to find a feasible path, and is particularly suitable for task scenarios that require absolute photothermal safety, such as permanent shadow zone edge exploration and ultra-long-term residence observation.

[0081] 3. In the asymmetric constraint mode of lunar rover path planning, when the positive time increment parameter dt1 is set to zero, the system will switch to a history-dependent decision architecture. At this time, the time evaluation domain is simplified from bidirectional time-space coupling to reverse one-way convergence ([T0-dt2, T0]), forming a path generation mechanism with memory reinforcement characteristics. This special configuration is not only suitable for fast parking scenarios during the lunar rover's sleep phase, but also can be used as a dynamic retreat plan during complex terrain traversal. Its essence is to sacrifice the planning freedom degree of future time dimension in exchange for deep understanding and accurate reconstruction of historical environmental state, establishing a nonlinear balance relationship between path feasibility guarantee and system resource consumption.

[0082] 4. In the forward-looking constraint mode of lunar rover path planning, when the reverse time increment parameter dt2 is set to zero, the system will enable the forward spatiotemporal coupling decision framework, focusing the time evaluation domain on the future extended interval [T0, T0+dt1], forming a path generation paradigm with predictive reinforcement characteristics. This configuration not only applies to the path pre-planning scenario during the lunar rover wake-up phase, but also plays a key role in key nodes such as crater transition and lunar day alternation. Its essence is to break the path dependence of historical environmental states, build a flexible decision space for future uncertainty, and achieve a quantitative balance between illumination safety margin and path optimality.

[0083] In the spatiotemporal coupling decision framework of large-scale lunar rover path planning, when the spatial span of the task area exceeds the short-term reachable range of the mobile system, the illumination safety window center time T0 will evolve into a dynamic time-varying parameter, forming a continuous coupling relationship between position coordinates and time dimensions. Its core value lies in breaking the conservative dilemma caused by spatiotemporal decoupling in large-scale path planning, providing a dynamic safety boundary with physical consistency for lunar rover path planning.

[0084] The forward and reverse illumination safety corridors are generated according to the illumination safety window model, pre-set single-step movement distance, and pre-set movement time interval. Under this framework, the forward and reverse illumination safety corridors are defined as spatiotemporal composite regions that satisfy multiple dynamic constraints: the spatial dimension must be verified by three-dimensional terrain shielding rate and solar incidence angle tolerance detection analysis, and the time dimension must ensure that the illumination at any time within the time window always meets the task requirements. As shown in Figure 5 The forward and reverse illumination safety corridors adopt a dynamic annular spatiotemporal grid strategy, with A as the starting point of the lunar rover movement to construct a concentric ring decision domain: the core ring C1, radius dL, center time T0; the secondary ring C2-C1, radius 2×dL, center time T1=T0+dT, with dT as the illumination duration starting from T0; the lower ring C3-C2, radius 3×dL, center time T2=T0+2×dT.

[0085] In the dynamic parameter optimization framework, the single-step movement distance parameter dL and the movement time interval parameter dT adopt the same adaptive adjustment mechanism: their initial values are based on the weighted average calculation of the lunar rover historical task database. As the task progresses, the dynamic optimization of dL and dT relies on a two-layer fusion architecture:

[0086] The bottom layer updates in real time through task data truncation weighted mean; the top layer introduces a human-machine collaborative decision-making interface, allowing operators to inject prior knowledge (such as the orientation of high-value scientific targets) for directional intervention.

[0087] The model is particularly suitable for large-scale scientific exploration tasks, and realizes adaptive balance of computing resources and planning accuracy through dynamic contraction and expansion of the annular domain. The innovation lies in decoupling the traditional uniform space-time grid and reconstructing it into an annular decision system with time-space coupling characteristics.

[0088] Further combined Figure 2 The process of generating the forward and reverse light safety corridor is described as follows:

[0089] Set the moving time interval parameter dT through automatically iteratively corrected data or manually edited data.

[0090] Set the single-step moving distance parameter dL through automatically iteratively corrected data or manually edited data.

[0091] Set the forward and reverse time increment parameters dt1 and dt2 through manual editing of data, and the order of the above three steps is not specifically limited.

[0092] Read and parse the light forecast file: in the multi-source data fusion preprocessing stage of the lunar rover path planning, a heterogeneous data stream parallel processing engine is used to parse the light forecast file, and the forward and reverse light safety corridors are generated according to the above description, and the specific details are not repeated.

[0093] In the above step S2, the device determines the normalized light energy availability index parameter according to the forward and reverse light safety corridors and the light forecast file, and calculates the normalized light energy availability index according to the normalized light energy availability index parameter. The determination of the normalized light energy availability index parameter according to the forward and reverse light safety corridors and the light forecast file comprises:

[0094] Determine the light duration of each level ring of the forward and reverse light safety corridor corresponding to the center time as the time starting point; as Figure 5 shown, and referring to the corresponding textual description above, taking the secondary ring C2-C1 as an example, the light duration corresponding to the center time as the time starting point is dT.

[0095] The normalized light energy availability index parameter is calculated according to the light duration and the light forecast file time range of the light forecast file. The calculation of the normalized light energy availability index according to the normalized light energy availability index parameter comprises:

[0096] The normalized light energy availability index is calculated according to the following formula:

[0097] S(x, y) = Tm / (t_max-t_min);

[0098] wherein S(x, y) is the normalized light energy availability index, Tm is the light duration, t_max is the maximum value in the light forecast file time range, and t_min is the minimum value in the light forecast file time range. Wherein x and y are the coordinates of each point (without considering the height coordinate) in the digital elevation map of the lunar surface.

[0099] Referring to the above example, dT is taken as a specific value of Tm, and substituted into the above formula to calculate the normalized light energy availability index S(x, y).

[0100] As a quantitative representation of the local light safety window, the forward and reverse light safety corridor can frame the feasible region that meets the basic task constraints, but its static threshold characteristics are difficult to effectively integrate the influence of the global time-varying lunar surface light field on path planning.

[0101] Therefore, a hierarchical light chasing model (forward and reverse light safety corridor) based on spatiotemporal correlation characteristics is constructed, which decouples the light conditions by distance and time in multiple levels, establishes a quantitative mapping relationship between dynamic light conditions and path accessibility, as shown in the above S(x, y) calculation formula, which can significantly improve the autonomous adaptive ability of path planning in complex light environment.

[0102] The hierarchical light chasing model constructs a spatiotemporal coupling analysis framework based on distance attenuation effect, adopts a concentric ring structure with moving starting point A as the center, and discretizes the region with the maximum single-step travel distance dL of the lunar rover as the radial resolution, forming a dynamically expanding ring-shaped decision domain. In each ring domain, the remaining effective light duration of each grid point relative to the center time T is calculated to ensure that the path segments in different ring regions are spatiotemporally matched with the light window corresponding to the time period.

[0103] In the above step S3, the device determines the shadow coverage cost according to the normalized light energy availability index, and superimposes the shadow coverage cost on the forward and reverse light safety corridor to obtain a light cost map. The determination of the shadow coverage cost according to the normalized light energy availability index includes:

[0104] The calculation result of subtracting 1 from the normalized light energy availability index is determined as the shadow coverage cost. In the light condition analysis, the value of the center time T continues the unified standard of the step "generating forward and reverse light safety corridors according to light forecast files and pre-setting information", and an incremental time division strategy is adopted for different ring regions:

[0105] The circle C1 in the core region, whose illumination modeling is based on the center time T1; when extending to the annular C2-C1, the center time is adjusted to T2 to reflect the change of the solar azimuth angle; when the analysis range extends to the C3-C2 annular region, the center time is further moved to T3. This layered and progressive time setting not only maintains the time sequence coherence of the analysis of each region, but also accurately matches the dynamic illumination characteristics of the lunar surface, providing a spatiotemporal coupled solar illumination evolution model for path planning.

[0106] In the path planning model, the illumination cost function quantifies the relative illumination duration of the target point in the future moving time domain, establishing a dynamic mapping relationship between the light energy resource distribution and the path selection: when a certain region can maintain longer effective illumination time after moving decision, its illumination cost parameter will quickly decay, thereby enhancing the path planning algorithm's tendency to use this point as a navigation node.

[0107] This model not only incorporates spatiotemporal coupling factors such as lunar solar altitude periodicity and terrain shielding effect into the cost calculation system, but also introduces illumination persistence weight, achieving multi-dimensional optimization goal, so that the path planning result can not only avoid the risk of energy interruption caused by long-term shadow, but also fully utilize the conditions of the illumination advantage area, ultimately forming a globally optimized trajectory with self-adaptive ability to the dynamic lunar light environment.

[0108] In the illumination constraint fusion stage, first, the generated forward and reverse illumination safety corridor is superimposed with the generated shadow coverage (shadow coverage cost), and then the path planning environment cost map is introduced by weighted superposition, realizing multi-dimensional target optimization, as shown in Figure 6 The green module in the figure is the innovative module of the present application, which replaces the illumination cost calculation method of the traditional scheme (blue module in Figure 6 ).

[0109] In the above step S4, the device performs polar region path planning of the lunar rover according to the illumination cost map and the pre-acquired terrain through the cost map. The polar region path planning of the lunar rover according to the illumination cost map and the terrain through the cost map includes:

[0110] generating an environment cost map according to the illumination cost map and the terrain through cost map;

[0111] performing heuristic search and path smoothing processing on the environment cost map to obtain a polar region path planning result of the lunar rover. The above Figure 1 related descriptions can be referred to, and will not be repeated.

[0112] The moon car polar region path planning method based on dynamic light condition analysis provided by the embodiment of the application proposes an adaptive collaborative light safety window model, including:

[0113] The light safety window model in the moon car path planning, the model takes the time reference point T0 as the spatiotemporal coupling analysis core, constructs a dynamic evaluation interval [T0-dt2, T0+dt1] through forward and reverse time increment parameters dt1 / dt2, the interval not only represents the light feature of the current moment, but also establishes a continuous time domain containing historical light change mode and future light evolution trend through the forward deduction and reverse tracing mechanism. The forward and reverse time increment parameter dt1 / dt2 setting strategy mainly includes: instantaneous state-based light constraint strategy, full-time domain tight constraint strategy, history-dependent strategy, forward spatiotemporal coupling strategy.

[0114] The moon car path planning hierarchical light chasing model is also proposed, including:

[0115] A spatiotemporal coupling analysis framework is constructed based on the distance attenuation effect, a concentric ring hierarchical structure with a moving starting point A as the center is adopted, and the region is discretized with the moon car single-step maximum travel distance dL as the radial resolution to form a dynamically expanding ring decision domain. The moon car path planning hierarchical light chasing model decouples the light condition by distance and time in multiple levels, establishes a quantitative mapping relationship between the dynamic light condition and the path accessibility, enhances the tendency of the path planning algorithm to take this point as a navigation node, and helps to form a global optimized trajectory with adaptive ability to the dynamic light environment on the moon surface.

[0116] The moon car polar region path planning method based on dynamic light condition analysis provided by the embodiment of the application has the following beneficial technical effects:

[0117] 1. Key technical innovation in light constraint modeling: innovatively introduce forward and reverse time increment parameters (dt1 / dt2) to construct a dynamic evaluation interval, establish a continuous time domain containing historical light change and future evolution trend through forward deduction and reverse tracing mechanism, and form a flexible configurable spatiotemporal composite safety corridor.

[0118] 2. Key technical innovation in spatiotemporal coupling decision: adopt a dynamic ring spatiotemporal grid strategy, construct a multi-level concentric ring decision domain by adaptively adjusting the moving distance parameter dL and the time interval parameter dT, realize dynamic decoupling and physical consistency reconstruction of spatiotemporal constraints in large-scale path planning.

[0119] 3. The specially developed human-machine collaborative dynamic configuration mechanism allows the operator to flexibly switch between different task scenarios (such as extreme constraints, asymmetric constraints, etc.) decision-making modes, to establish a nonlinear balance between planning real-time, safety redundancy and resource consumption, and finally to form a flexible decision-making space with prediction reinforcement and memory reinforcement characteristics, significantly improving the long-period exploration capability and path planning confidence of the lunar rover under complex terrain and dynamic lighting conditions.

[0120] 4. Breakthrough in dynamic lighting modeling: innovatively build a hierarchical light chasing model based on spatiotemporal correlation characteristics, decouple the distance attenuation effect and the time dimension strategy, decompose the global time-varying light field on the moon into concentric ring-shaped decision domains centered on the moving starting point, and use the single-step maximum travel dL as the radial resolution to establish a dynamically expanding ring-shaped spatiotemporal grid.

[0121] 5. Important breakthrough in spatiotemporal collaborative optimization: propose a gradual time division strategy, use a time sequence coherent analysis method that moves the center time in different ring-shaped areas, accurately match the dynamic shift of the sun's azimuth angle and the terrain shielding effect, and form a physically consistent light evolution prediction model; Breakthrough to convert the normalized light energy availability index S(x, y) into a shadow coverage cost parameter, build a dynamic mapping relationship between light energy resource distribution and path selection, quantify the relative light continuity weight of the target point in the future moving time domain, realize the dual optimization goals of energy risk avoidance and light advantage utilization, and finally generate a globally optimal path that can respond to the periodic change of the sun's elevation angle and adapt to the spatiotemporal coupling characteristics of the terrain shielding, significantly improving the path planning capability and light and heat safety guarantee level of long-period exploration tasks in complex lunar surface environment.

[0122] The lunar rover polar region path planning method based on dynamic lighting condition analysis provided by the embodiment of the application generates forward and reverse lighting safety corridors according to the lighting forecast file and pre-set information; determines a normalized light energy availability index parameter according to the forward and reverse lighting safety corridors and the lighting forecast file, and calculates the normalized light energy availability index according to the normalized light energy availability index parameter; determines a shadow coverage cost according to the normalized light energy availability index, and superimposes the shadow coverage cost on the forward and reverse lighting safety corridors to obtain a lighting cost map; and performs lunar rover polar region path planning according to the lighting cost map and a pre-acquired terrain passing cost map, realizing a technical breakthrough in dynamic lighting condition adaptation and multi-constraint collaborative optimization in long-period exploration tasks in complex lunar surface environment, and significantly improving the global path planning capability of the lunar rover in extreme terrain, dynamic lighting, and large-scale unknown areas.

[0123] In the optional embodiment above, the preset information comprises a preset moving time interval, a preset single-step moving distance and a preset forward-reverse time increment parameter; correspondingly, the generating of the forward-reverse light safety corridor according to the light forecast file and the preset information comprises:

[0124] The central time of the moving starting point of the lunar rover is obtained by reading the light forecast file, and a light safety window model is determined according to the preset forward-reverse time increment parameter with the central time as a time reference point; for details, refer to the above embodiment.

[0125] The forward-reverse light safety corridor is generated according to the light safety window model, the preset single-step moving distance and the preset moving time interval; for details, refer to the above embodiment.

[0126] In the optional embodiment above, the determining of the normalized light energy availability index parameter according to the forward-reverse light safety corridor and the light forecast file comprises:

[0127] The light duration corresponding to each level of the forward-reverse light safety corridor is determined with the central time as a time starting point; for details, refer to the above embodiment.

[0128] The normalized light energy availability index parameter is calculated according to the light duration and the light forecast file time range of the light forecast file; for details, refer to the above embodiment.

[0129] In the optional embodiment above, the calculating of the normalized light energy availability index according to the normalized light energy availability index parameter comprises:

[0130] The normalized light energy availability index is calculated according to the following formula:

[0131] S(x, y) = Tm / (t_max-t_min); for details, refer to the above embodiment.

[0132] Wherein, S(x, y) is the normalized light energy availability index, Tm is the light duration, t_max is the maximum value in the light forecast file time range, and t_min is the minimum value in the light forecast file time range. For details, refer to the above embodiment.

[0133] In the optional embodiment above, the determining of the shadow coverage cost according to the normalized light energy availability index comprises:

[0134] The calculation result of subtracting 1 from the normalized light energy availability index is determined as the shadow coverage cost. For details, refer to the above embodiment.

[0135] In the optional embodiment described above, the lunar rover polar region path planning based on the illumination cost map and the pre-acquired terrain through cost map comprises:

[0136] An environment cost map is generated according to the illumination cost map and the terrain through cost map; refer to the description of the above embodiments, which will not be repeated.

[0137] Heuristic search and path smoothing processing are performed on the environment cost map to obtain a lunar rover polar region path planning result; refer to the description of the above embodiments, which will not be repeated.

[0138] Figure 7 is a structural schematic diagram of a lunar rover polar region path planning device based on dynamic illumination condition analysis provided by an embodiment of the present application, as Figure 7 shown, the lunar rover polar region path planning device based on dynamic illumination condition analysis provided by the embodiment of the present application comprises a generation unit 701, an acquisition unit 702, a superposition unit 703 and a planning unit 704, wherein:

[0139] The generation unit 701 is configured to generate a forward and reverse illumination safety corridor according to an illumination forecast file and pre-setting information; the acquisition unit 702 is configured to determine a normalized light energy availability index parameter according to the forward and reverse illumination safety corridor and the illumination forecast file, and calculate a normalized light energy availability index according to the normalized light energy availability index parameter; the superposition unit 703 is configured to determine a shadow coverage cost according to the normalized light energy availability index, and superimpose the shadow coverage cost to the forward and reverse illumination safety corridor to obtain an illumination cost map; and the planning unit 704 is configured to perform lunar rover polar region path planning according to the illumination cost map and a pre-acquired terrain through cost map.

[0140] Specifically, the generation unit 701 in the device is configured to generate a forward and reverse illumination safety corridor according to an illumination forecast file and pre-setting information; the acquisition unit 702 is configured to determine a normalized light energy availability index parameter according to the forward and reverse illumination safety corridor and the illumination forecast file, and calculate a normalized light energy availability index according to the normalized light energy availability index parameter; the superposition unit 703 is configured to determine a shadow coverage cost according to the normalized light energy availability index, and superimpose the shadow coverage cost to the forward and reverse illumination safety corridor to obtain an illumination cost map; and the planning unit 704 is configured to perform lunar rover polar region path planning according to the illumination cost map and a pre-acquired terrain through cost map.

[0141] The lunar rover polar region path planning device based on dynamic light condition analysis provided by the embodiment of the application generates a forward and reverse light safety corridor according to a light prediction file and preset information; determines a normalized light energy availability index parameter according to the forward and reverse light safety corridor and the light prediction file, and calculates a normalized light energy availability index according to the normalized light energy availability index parameter; determines a shadow coverage cost according to the normalized light energy availability index, and superimposes the shadow coverage cost to the forward and reverse light safety corridor to obtain a light cost map; and performs lunar rover polar region path planning according to the light cost map and a pre-acquired terrain passing cost map, which realizes a technical breakthrough of dynamic light condition adaptation and multi-constraint collaborative optimization in a long-period exploration task under a complex lunar surface environment, and significantly improves the global path planning capability of the lunar rover in an extreme terrain, dynamic light and a large unknown area.

[0142] The embodiment of the lunar rover polar region path planning device based on dynamic light condition analysis provided by the embodiment of the application can be specifically used for executing the processing procedures of the above-mentioned method embodiments, and the functions thereof will not be repeated here, and the detailed description thereof can be referred to the above-mentioned method embodiments.

[0143] Figure 8 The computer device entity structure schematic diagram provided by the embodiment of the application is shown as in Figure 8 The computer device includes a memory 801, a processor 802, and a computer program stored on the memory 801 and executable on the processor 802, and the processor 802 implements the following method when executing the computer program.

[0144] The forward and reverse light safety corridor is generated according to the light prediction file and the preset information;

[0145] The normalized light energy availability index parameter is determined according to the forward and reverse light safety corridor and the light prediction file, and the normalized light energy availability index is calculated according to the normalized light energy availability index parameter;

[0146] The shadow coverage cost is determined according to the normalized light energy availability index, and the shadow coverage cost is superimposed to the forward and reverse light safety corridor to obtain the light cost map;

[0147] The lunar rover polar region path planning is performed according to the light cost map and the pre-acquired terrain passing cost map.

[0148] The embodiment discloses a computer program product, which includes a computer program, and the computer program implements the following method when executed by a processor.

[0149] The forward and reverse light safety corridor is generated according to the light prediction file and the preset information;

[0150] determine a normalized light energy availability index parameter according to the positive and negative light safety corridor and the light forecast file, and calculate a normalized light energy availability index according to the normalized light energy availability index parameter;

[0151] determine a shadow coverage cost according to the normalized light energy availability index, and superimpose the shadow coverage cost to the positive and negative light safety corridor to obtain a light cost map;

[0152] plan a polar region path of the lunar rover according to the light cost map and a pre-acquired terrain passing cost map.

[0153] The embodiment provides a computer readable storage medium, which stores a computer program, and the computer program is executed by a processor to implement the following method.

[0154] generate a positive and negative light safety corridor according to a light forecast file and preset information;

[0155] determine a normalized light energy availability index parameter according to the positive and negative light safety corridor and the light forecast file, and calculate a normalized light energy availability index according to the normalized light energy availability index parameter;

[0156] determine a shadow coverage cost according to the normalized light energy availability index, and superimpose the shadow coverage cost to the positive and negative light safety corridor to obtain a light cost map;

[0157] plan a polar region path of the lunar rover according to the light cost map and a pre-acquired terrain passing cost map.

[0158] Compared with the technical solution in the prior art, the lunar rover polar region path planning method based on dynamic light condition analysis provided by the embodiment has the following advantages: a positive and negative light safety corridor is generated according to a light forecast file and preset information; a normalized light energy availability index parameter is determined according to the positive and negative light safety corridor and the light forecast file, and a normalized light energy availability index is calculated according to the normalized light energy availability index parameter; a shadow coverage cost is determined according to the normalized light energy availability index, and the shadow coverage cost is superimposed to the positive and negative light safety corridor to obtain a light cost map; and a polar region path of the lunar rover is planned according to the light cost map and a pre-acquired terrain passing cost map, which realizes a technical breakthrough of dynamic light condition adaptation and multi-constraint collaborative optimization in a long-period exploration task in a complex lunar surface environment, and significantly improves the global path planning capability of the lunar rover in an extreme terrain, dynamic light and a large unknown area.

[0159] Those skilled in the art will appreciate that embodiments of the present application can be readily used as a method, a system or a computer program product. Accordingly, the present application can take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application can take the form of a computer program product on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROMs, optical storage devices, etc.) embodying computer readable program code.

[0160] The present application is described in reference to the flowchart illustrations and / or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general purpose computer, special purpose computer, embedded processor or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart illustrations and / or block diagrams block or blocks. Figure 1 one or more functions specified in the flowchart illustrations and / or block diagrams block or blocks. Figure 1 one or more functions specified in the flowchart illustrations and / or block diagrams block or blocks.

[0161] These computer program instructions can also be stored in a computer- readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instructions which implement the function specified in the flowchart illustrations and / or block diagrams block or blocks. Figure 1 one or more functions specified in the flowchart illustrations and / or block diagrams block or blocks. Figure 1 one or more functions specified in the flowchart illustrations and / or block diagrams block or blocks.

[0162] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart illustrations and / or block diagrams block or blocks. Figure 1 one or more functions specified in the flowchart illustrations and / or block diagrams block or blocks. Figure 1 one or more functions specified in the flowchart illustrations and / or block diagrams block or blocks.

[0163] In the description of the present specification, the description of the terms "one embodiment", "one specific embodiment", "some embodiments", "for example", "an example", "a specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Also, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in one or more embodiments or examples.

[0164] The specific embodiments described above further illustrate the purposes, technical solutions and beneficial effects of the present application. It should be understood that the above description is only for specific embodiments of the present application and is not intended to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A lunar rover polar region path planning method based on dynamic lighting condition analysis, characterized in that, The method comprises the following steps: generating a forward and reverse light safety corridor according to a light forecast file and preset information; determining a normalized light energy availability index parameter according to the forward and reverse light safety corridor and the light forecast file, and calculating a normalized light energy availability index according to the normalized light energy availability index parameter; determining a shadow coverage cost according to the normalized light energy availability index, and superimposing the shadow coverage cost on the forward and reverse light safety corridor to obtain a light cost map; performing polar region path planning of a lunar rover according to the light cost map and a previously acquired terrain through cost map; the preset information comprises a preset moving time interval, a preset single-step moving distance and a preset forward and reverse time increment parameter; correspondingly, the step of generating the forward and reverse light safety corridor according to the light forecast file and the preset information comprises the following steps: reading the light forecast file to obtain a central time of a starting point of movement of the lunar rover, taking the central time as a time reference point, and determining a light safety window model according to the preset forward and reverse time increment parameter; generating the forward and reverse light safety corridor according to the light safety window model, the preset single-step moving distance and the preset moving time interval; the step of determining the normalized light energy availability index parameter according to the forward and reverse light safety corridor and the light forecast file comprises the following steps: determining a light duration corresponding to each level ring of the forward and reverse light safety corridor, with the central time as a time starting point; calculating the normalized light energy availability index parameter according to the light duration and a light forecast file time range of the light forecast file.

2. The lunar rover polar region path planning method based on dynamic lighting condition analysis according to claim 1, characterized in that, the step of calculating the normalized light energy availability index according to the normalized light energy availability index parameter comprises the following steps: calculating the normalized light energy availability index according to the following formula: S(x, y) = Tm / ( t_max-t_min )； wherein, S(x, y) is the normalized light energy availability indicator, Tm is the light duration, t_max is the maximum value in the light forecast file time range, t_min is the minimum value in the light forecast file time range.

3. The lunar rover polar region path planning method based on dynamic lighting condition analysis of claim 1, wherein, the step of determining the shadow coverage cost according to the normalized light energy availability index comprises the following step: determining the shadow coverage cost as a calculation result of subtracting the normalized light energy availability index from 1.

4. The lunar rover polar region path planning method based on dynamic lighting condition analysis according to any one of claims 1 to 3, characterized in that, the step of performing polar region path planning of the lunar rover according to the light cost map and the previously acquired terrain through cost map comprises the following steps: generating an environment cost map according to the light cost map and the terrain through cost map; performing heuristic search and path smoothing processing on the environment cost map to obtain a polar region path planning result of the lunar rover.

5. A lunar rover polar region path planning device based on dynamic lighting condition analysis, characterized in that, The method comprises the following steps: a generating unit is configured to generate a forward and reverse light safety corridor according to a light forecast file and preset information; an obtaining unit is configured to determine a normalized light energy availability index parameter according to the forward and reverse light safety corridor and the light forecast file, and calculate a normalized light energy availability index according to the normalized light energy availability index parameter; a superimposing unit is configured to determine a shadow coverage cost according to the normalized light energy availability index, and superimpose the shadow coverage cost on the forward and reverse light safety corridor to obtain a light cost map; a planning unit is configured to perform polar region path planning of a lunar rover according to the light cost map and a previously acquired terrain through cost map. The pre-setting information includes a pre-setting moving time interval, a pre-setting single-step moving distance and a pre-setting forward and reverse time increment parameter; correspondingly, the generating unit is specifically used for: reading the light forecast file to obtain a central time of a moving starting point of the lunar rover, taking the central time as a time reference point, and determining a light safety window model according to the pre-setting forward and reverse time increment parameter; generating the forward and reverse light safety corridors according to the light safety window model, the pre-setting single-step moving distance and the pre-setting moving time interval; The acquisition unit is specifically used for: determining the light duration corresponding to each level ring of the forward and reverse light safety corridors respectively, with the central time as a time starting point; calculating the normalized light energy availability index parameter according to the light duration and a light forecast file time range of the light forecast file.

6. A computer device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor executes the computer program to implement the method in any one of claims 1 to 4.

7. A computer readable storage medium characterized in that, The computer readable storage medium stores a computer program, and the computer program is executed by the processor to implement the method in any one of claims 1 to 4.

8. A computer program product, characterised in that, The computer program product includes a computer program, and the computer program is executed by the processor to implement the method in any one of claims 1 to 4.

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