Search Results (80)

Lunar lava tubes are subsurface cavities generated by volcanic activity and are regarded as promising targets for exploration because they can offer natural shielding and potentially support future lunar infrastructures as protected shelters and scientific laboratories. Autonomous navigation in these environments remains challenging due to the absence of illumination, sparse or repetitive geometric features, uneven terrain, and intermittent communications that limit teleoperation. In this framework, the Italian Space Agency (ASI) is pursuing a dedicated mission, and OHB Italia has been appointed the prime contractor to perform a candidate system-architecture study for lava tube exploration. This paper presents the activities and results related to the definition of the subsurface Guidance, Navigation, and Control (GNC) algorithm for a rover/hopper system. To address the above constraints, this study investigates the requirements for autonomous onboard navigation, focusing on sensor selection for Simultaneous Localization and Mapping (SLAM) as a fundamental prerequisite for mission success. A weighted-criteria evaluation framework is developed to assess various sensing modalities, considering mission-specific constraints. Based on this analysis, a sensor configuration optimized for GPS-denied and unilluminated environments is proposed. The effectiveness of the selected sensing architecture is validated through a simulation campaign conducted in simulation environments (CoppeliaSim v4.10.0/MATLAB 2025a), using two representative SLAM pipelines (ICP and LOAM) in LiDAR-only and LiDAR + IMU configurations. Finally, a modular Guidance, Navigation, and Control (GNC) architecture incorporating frontier-based exploration is proposed. Full article

Precise in situ characterization of the mechanical properties of lunar regolith is critical for future lunar base construction and resource exploitation. However, existing detection methods predominantly rely on indirect inversion from rover wheel-soil interactions, which exhibit limitations in accuracy, real-time capability, and detection depth. Furthermore, specialized automated equipment capable of adapting to the complex lunar surface environment remains lacking. To address these challenges, this study presents the design and development of a novel autonomous in situ penetration-shear apparatus. The device automatically executes penetration and shear operations while recording real-time data, with a maximum penetration force of 25 N, shear torque of 2.5 N·m, penetration depth of 300 mm, and rotation angle of 360°. Given the maximum normal load constraint of 16 N imposed by the lunar rover platform, 24 probe configurations—varying in conicity, projected area, and vane number—were systematically evaluated using lunar soil simulants with three particle size distributions and two density levels. Multi-objective optimization was conducted to maximize detection efficiency, specifically penetration depth and shear torque, subject to a lightweight payload constraint (16 N). The multi-objective optimization reveals a fundamental trade-off: smaller conicity angles and projected areas favor deeper penetration, while larger projected areas enhance shear torque response. Under the 16 N constraint, the Pareto analysis identifies that a combination of moderate projected area, small conicity, and fewer vanes achieves the most balanced performance across all soil conditions. Results further demonstrate that increasing particle size and density substantially suppress both penetration capability and shear torque response, with compaction being the dominant factor limiting probe advancement under constrained normal loading. Results indicate that the optimal probe configuration comprises a 15° conicity, 324 mm² projected area, and two vanes, achieving an average penetration depth of 51.61 mm and average shear torque of 0.06 N·m across all test conditions. This study validates a complete automated system for characterizing lunar soil mechanical properties and provides an efficient, reliable hardware solution for future unmanned lunar exploration missions through optimized probe design. These findings establish a solid technical foundation for deep, high-precision in situ investigation of lunar soil structure and mechanical parameters, with significant implications for lunar base site selection and In Situ Resource Utilization (ISRU). Full article

In order to enable an autonomous navigation capability in environments where global navigation satellite systems (GNSSs) are either denied (e.g., areas with intentional jamming or spoofing) or not available yet (Moon, Mars), Sodern is currently developing star trackers for Earth-based aircrafts and space rovers. This system is designed to compensate for inertial sensor (IMU)-induced drifts by providing an absolute attitude reference. The resulting celestial navigation system (CNS) aims at providing a position evaluation with a 100 m class precision, independent of the mission duration. In this paper, we present the star tracker design with a specific focus on daytime capabilities and the hybridization strategy to implement the retrieved celestial attitude in the CNS. Additionally, we present two application cases currently under development at Sodern, for space rovers and aircrafts. We evaluate the typical performances that can be reached depending on the IMU and star tracker class in harsh environments (luminance, dynamics, radiations…). We conclude with a brief presentation of future developments in this field. Full article

The wheels of lunar rovers are prone to bouncing during travel in the low gravity and rugged terrain conditions of the lunar surface, and poor matching of wheel alignment parameters can easily lead to tire wear in such conditions. Focusing on the double-wishbone suspension of lunar rovers, this study presents a wheel alignment parameter optimization method for tire wear reduction. First, a tire brush model is established, and it is determined that the toe angle and camber angle are the main factors affecting the tire wear work. And as the camber angle and toe angle increase, the tire wear work becomes greater. Then, a multi-body dynamic model of the double-wishbone independent suspension in a low-gravity environment is established. Taking the minimum tire wear as the optimization objective, the optimal solution set of alignment parameters such as the tire camber angle and toe angle obtained and the optimal hardpoint coordinate positions are determined. The variation range of the toe angle is optimized from [−0.55°, 1.58°] to [−0.37°, 1.32°]. After optimization, the variation in the toe angle is reduced by 20.4%, the change rate of the camber angle becomes smoother, and the comprehensive wear work of the tire is reduced by 17.47%. The research results provide theoretical guidance for the optimization of wheel alignment parameters of the double-wishbone suspension of the lunar rover. Full article

Exploring the lunar complex and extreme terrain presents formidable challenges for conventional lunar rovers. To address these limitations, this study proposes a novel hexapod jumping hybrid robot that incorporates a “figure-of-eight” (butterfly-shaped) six-branched wheel-legged mechanism and a jumping system that stores elastic energy via deformation of its elastic body. Inspired by the multimodal locomotion of grasshoppers, the robot dynamically switches between two operational modes: high-efficiency wheeled locomotion on relatively flat surfaces and agile jumping to traverse steep slopes and surmount large obstacles. A bio-inspired gait, inspired by the crawling patterns of a hexapod insect, is implemented using a Central Pattern Generator (CPG)-based controller to produce coordinated, rhythmic limb movements. Dynamic simulations of the jumping mechanism were conducted to optimize the critical parameters of the elastic structure and its associated control strategy. Experiments on a physical prototype were conducted to validate the robot’s wheeled mobility and jumping performance. The results demonstrate that the robot exhibits excellent adaptability to rugged terrains and obstacle-dense environments. The integration of multimodal locomotion and adaptive gait control significantly enhances the robot’s operational robustness and survivability in the harsh lunar environment, opening new possibilities for future lunar exploration missions. Full article

Future lunar south pole missions face dual challenges of highly variable illumination and rugged terrain that directly constrain rover mobility and energy sustainability. To address these issues, this study proposes a dynamic illumination-constrained spatio-temporal A* (DIC3D-A*) path-planning algorithm that jointly optimizes terrain safety and illumination continuity in polar environments. Using high-resolution digital elevation model data from the Lunar Reconnaissance Orbiter Laser Altimeter, a 1300 m × 1300 m terrain model with 5 m/pixel spatial resolution was constructed. Hourly solar visibility for November–December 2026 was computed based on planetary ephemerides to generate a dynamic illumination dataset. The algorithm integrates slope, distance, and illumination into a unified heuristic cost function, performing a time-dependent search in a 3D spatiotemporal state space. Simulation results show that, compared with conventional A* algorithms considering only terrain or distance, the DIC3D-A* algorithm improves CSDV by 106.1% and 115.1%, respectively. Moreover, relative to illumination-based A* algorithms, it reduces the average terrain roughness index by 17.2%, while achieving shorter path length and faster computation than both the Rapidly-exploring Random Tree Star and Deep Q-Network baselines. These results demonstrate that dynamic illumination is the dominant environmental factor affecting lunar polar rover traversal and that DIC3D-A* provides an efficient, energy-aware framework for illumination-adaptive navigation in upcoming missions such as Chang’E-7. Full article

Space exploration is a major global focus, advancing knowledge and exploiting new resources beyond Earth. Bioinspired design—drawing principles from nature—offers systematic pathways to increase the capability and intelligence of space robots. Prior reviews have emphasized on-orbit manipulators or lunar rovers, while a comprehensive treatment across application domains has been limited. This review synthesizes bioinspired capability and intelligence for space exploration under varied environmental constraints. We highlight four domains: adhesion and grasping for on-orbit servicing; terrain-adaptive mobility on granular and rocky surfaces; exploration intelligence that couples animal-like sensing with decision strategies; and design methodologies for translating biological functions into robotic implementations. Representative applications include gecko-like dry adhesives for debris capture, beetle-inspired climbers for truss operations, sand-moving quadrupeds and mole-inspired burrowers for granular regolith access, and insect flapping-wing robots for flight under Martian conditions. By linking biological analogues to quantitative performance metrics, this review highlights how bioinspired strategies can significantly improve on-orbit inspection, planetary mobility, subsurface access, and autonomous decision-making. Framed by capability and intelligence, bioinspired approaches reveal how biological analogues translate into tangible performance gains for on-orbit inspection, servicing, and long-range planetary exploration. Full article

Developing autonomous technologies will enable humanity to considerably expand our lunar and space exploration capabilities. Along with the technical challenges of developing autonomous technologies, there is also the issue of trust—stakeholders are often resistant to their use for a variety of psychological reasons. Nevertheless, several successful methods for gradually building trust have been developed for both terrestrial and space applications. Relevant case studies provide insights on how trust is built for stakeholders when it comes to self-driving vehicles, Artificial Intelligence in aviation, space station operations, satellite rendezvous missions, and Mars rover surface operations. Based on these case studies, we propose a generalized method for building trust with stakeholders and have applied it to a lunar construction pathfinder mission currently in development. Metrics for assessing success criteria for autonomous systems are provided as a means to progress through the proposed phases of autonomy deployment. Full article

Wheeled rovers are widely used in lunar and planetary exploration missions owing to their mechanical simplicity and energy efficiency. However, they face serious mobility challenges on sloped soft terrain, especially in terms of sideslip and loss of attitude angle when traversing across slopes. Previous research proposed using wheelbase extension/contraction and intentionally sinking wheels into the ground, thereby increasing shear resistance and reducing sideslip. Building upon this concept, this study proposes a novel recovery method that integrates beam extension/contraction and Archimedean screw-shaped wheels to enable lateral movement without rotating the rover body. The beam mechanism allows for independent wheel movement, maintaining stability by anchoring stationary wheels during recovery. Meanwhile, the helical structure of the screw wheels helps reduce lateral earth pressure by scraping soil away from the sides, improving lateral drivability. Driving experiments on a sloped sandbox test bed confirmed that the proposed 2DPPL (two-dimensional push-pull locomotion) method significantly reduces sideslip and prevents a drop in attitude angle during slope traversal. Full article

The Moon has become the focus of renewed interest for numerous space agencies and private companies worldwide. In the coming years, various scientific and commercial missions are planned, with a particular emphasis on exploring the South Pole. These missions include orbiters, landers, as well as both static and mobile rovers. For all these operations, continuous and accurate position knowledge is essential. This paper evaluates the performance of a navigation system designed for a lunar rover using the future satellite navigation infrastructure. It highlights the critical role of integrating multiple information sources, including a Digital Elevation Model (DEM) of the lunar surface and a high-precision Inertial Measurement Unit (IMU). The results demonstrate that a comprehensive suite of instruments enables highly accurate and reliable navigation for a mobile rover. While standalone satellite navigation, due to the reduced number of available sources, offers navigation accuracy of the orders of tens of meters, the addition of the DEM lowers the error at 5 m level; the IMU further improve by roughly 40% the performance on horizontal positioning. Full article

In lunar exploration missions, rovers must navigate multiple waypoints within strict time constraints while avoiding dynamic obstacles, demanding real-time, collision-free path planning. This paper proposes a digital twin-enhanced hierarchical planning method, A*-D3QN-Opt (A-Star-Dueling Double Deep Q-Network-Optimized). The framework combines the A* algorithm for global optimal paths in static environments with an improved D3QN (Dueling Double Deep Q-Network) for dynamic obstacle avoidance. A multi-dimensional reward function balances path efficiency, safety, energy, and time, while priority experience replay accelerates training convergence. A high-fidelity digital twin simulation environment integrates a YOLOv5-based multimodal perception system for real-time obstacle detection and distance estimation. Experimental validation across low-, medium-, and high-complexity scenarios demonstrates superior performance: the method achieves shorter paths, zero collisions in dynamic settings, and 30% faster convergence than baseline D3QN. Results confirm its ability to harmonize optimality, safety, and real-time adaptability under dynamic constraints, offering critical support for autonomous navigation in lunar missions like Chang’e and future deep space exploration, thereby reducing operational risks and enhancing mission efficiency. Full article

Reduced gravity may impair motion perception accuracy, especially in the absence of visual cues, which could degrade astronauts’ driving performance. The lack of prior research makes simulating realistic motion perception for lunar rover driving particularly challenging. We created a simulation system to quantitatively simulate the motion characteristics of a lunar rover at different gravity levels, and a software program based on the spatial orientation observer model was developed for the comparison of motion perception differences between Earth’s and lunar gravity. In comparison to Earth’s gravity, the lunar rover in lunar gravity demonstrates the following differences: (1) The rover exhibits a greater propensity to float and slip, and slower acceleration and deceleration. (2) Dynamic tilt perception may be more complicated with single vestibular information, while static tilt perception is greatly reduced; the introduction of visual information can notably improve the perception accuracy. Simulation results demonstrate that motion characteristics and perception of lunar rover driving exhibit a more variable trend at different gravity levels. An intuitive mathematical formulation was proposed to explain the single vestibular results. Our findings provide a basis for further optimizing lunar rover driving motion simulation strategies. Full article

The dynamic illumination conditions in the Moon’s polar region present challenges for future rover explorations, which require enhanced efficiency and intelligent data preprocessing for Sun-synchronous path planning. Within the Chang’E-7 polar exploration mission context, this study investigates automated, intelligent preprocessing of 2.5D illumination data from high-resolution Digital Elevation Models for polar rover global path planning. A preprocessing pipeline is developed using a Sun-synchronous spatiotemporal U-Net,3STU-Net, incorporating time-slice and time-series sub-networks, to streamline data handling and identify regions with favorable illumination. Subsequently, an enhanced A* algorithm named 3ST-A*, leveraging preprocessed data, is applied in a designated area of interest for global path-planning experimental validation. The findings significantly improve illumination data processing efficiency and advance path-planning research, offering valuable support for future lunar exploration missions. Full article

The SAMLER-KI (Semi-autonomous Micro Rover for Lunar Exploration using Artificial Intelligence) project aims to open up further potential for future lunar micro rover missions. The focus is on the conceptual design of a micro rover with a higher level of autonomy and the ability to survive the lunar night. Achieving this capability requires a sophisticated thermal design to endure the harsh lunar environment and maintain acceptable temperatures not only during the extreme cold of the lunar night but also while addressing the power demands of autonomous exploration activities during daytime operations. Simultaneously, the structural design must withstand the vibration loads experienced during rocket launch. The design process is challenged by the conflicting requirements between the structural and thermal subsystems, further compounded by the mission’s mass requirement of 20 kg. An initial rover design has been developed in alignment with these requirements and the overall mission scenario. This paper presents a structural and thermal assessment of the preliminary rover design concept under mission-relevant load conditions. The analyses identify critical design weaknesses, including major parasitic thermal pathways and structurally vulnerable components. Although the current design does not yet meet the imposed requirements, the findings provide essential insights into critical areas that show potential for improvement. These results are expected to guide future iterations towards achieving a feasible and robust thermal and structural design. Full article

The paper at hand evaluates the necessity of depicting topographic features like boulders on the lunar environment in thermal analyses for a size of up to 6.5 m in diameter. The question regarding the thermal influence becomes relevant when analysing a technical system within the lunar environment. This influence on the thermal behaviour of a test object is investigated in sensitivity studies. It is shown that the local surroundings can significantly alter a system’s net heat flux and can lead to overheating or critically cooling down instead of theoretically surviving when not considering local topographic features. Especially for small and lightweight systems ≤20 kg, like micro rovers, the effect of the surrounding on the system’s temperature becomes critical due to the low thermal capacity. Thus, it is a substantial aspect to be accounted for during the design phase as well as in mission operation. Full article