Mars Research Articles

RSU-Net: An Attention U-Net for Martian Rock Segmentation

Since rocks may collide with the rover or wear tires during the exploration mission of the Mars probe, and may contain rich geological information, identifying rocks in the scene is crucial for the navigation and obstacle avoidance of the Mars probe. Additionally, since the communication between the Mars rover and the earth is often intermittent and delayed during missions, it needs a certain degree of autonomy. Deep learning technologies such as semantic segmentation and target detection can meet this requirement to a certain extent, which facilitates the enhancement of safety and efficiency for the Mars rover. Rock segmentation is to divide the pixels of the rock from the image. However, the texture of the rock is often close to the texture of the surrounding sand, and some parts may be covered, so it is difficult to identify it correctly. To this end, this paper proposed RSU-Net (Rock Segmentation U-Net) and RSU-Net-L, which combine the SENet attention mechanism, and the latter achieves higher computational efficiency and inference speed by compressing the number of channels on the basis of the former. In addition, this paper established a dataset, MarsRock, for Mars rock segmentation to help the Mars rover for visual navigation. Its images come from “Tianwen-1”, which contains 1194 images, and each image has a corresponding rock label. And our experiments on the MarsRock dataset show that RSU-Net can achieve 99.07% accuracy and 67.71% F1-score. RSU-Net-L can achieve 98.99% accuracy and 66.67% F1-score while diminishing the number of parameter count by 43.7% and the number of FLOPs by 43.6%, while the FPS can reach 12.01 on a single RTX6000-24GB GPU.

Numerical Investigation of Gas Models for Retropropulsion Flows for Future Mars Missions

Supersonic retropropulsion is a key technology for next-generation rockets and necessary to land large payloads for human-scale missions. The recent decade has demonstrated the capability to land rockets on Earth as well as the reuse of said rockets to reduce cost. This capability thus far has relied on flight tests. For future missions to Mars, testing requires many compromises, as flight tests are not possible on Earth. Computational fluid dynamics (CFD) simulations are critical to the design and analysis of extraplanetary retropropulsion configurations. This work investigates a single-engine configuration that was previously tested in a wind tunnel using an air medium. The configuration is scaled to Martian conditions. Various gas modeling approaches are employed, including pure CO2, pseudo-species, and a chemical mechanism to model the afterburning of the engine plumes in the Martian atmosphere. The scale-resolving CFD simulations are compared to the simulation and experimental data of the air configuration. The lower-fidelity gas modeling simulations are also compared against the higher-fidelity chemical mechanism simulations to examine the impact of gas models on plume flowfields and forces and moments that are of interest to vehicle design.

Situation Awareness of Mars helicopter based on YOLOv7

Situation awareness on Mars is indispensable for various downstream applications such as navigation and path planning, mapping and scientific discover. However, current Mars rover platform suffered from the absence of global information, leading to mission reduction and the failure of global planning. Compared to the rover, Mars helicopter is a new type of attempt for Mars exploration, which can provide a wide range view of scenes to well support the above missions. To this end, in this paper we proposed a novel learning-based situation awareness model for Mars helicopter. We modified the Yolov7 model by embedding a new channel attention on its head to improve the accuracy of detection. Besides, we designed a Tiny-Scale Detection Module (TSDM) to capture small or hidden rocks in complex Martian surface. To achieve further refinement and validate our proposal, we built an open-source synthetic dataset in air view. After extensive experiments, our model achieved excellent outperforms than the baseline model in our Mars dataset.

Investigating Microbial Biosignatures in Aeolian Environments Using Micro-X-Ray: Simulation of PIXL Instrument Analyses at Jezero Crater Onboard the Perseverance Mars 2020 Rover.

Assessing the past habitability of Mars and searching for evidence of ancient life at Jezero crater via the Perseverance rover are the key objectives of NASA's Mars 2020 mission. Onboard the rover, PIXL (Planetary Instrument for X-ray Lithochemistry) is one of the best suited instruments to search for microbial biosignatures due to its ability to characterize chemical composition of fine scale textures in geological targets using a nondestructive technique. PIXL is also the first micro-X-ray fluorescence (XRF) spectrometer onboard a Mars rover. Here, we present guidelines for identifying and investigating a microbial biosignature in an aeolian environment using PIXL-analogous micro-XRF (μXRF) analyses. We collected samples from a modern wet aeolian environment at Padre Island, Texas, that contain buried microbial mats, and we analyzed them using μXRF techniques analogous to how PIXL is being operated on Mars. We show via μXRF technique and microscope images the geochemical and textural variations from the surface to ∼40 cm depth. Microbial mats are associated with heavy-mineral lags and show specific textural and geochemical characteristics that make them a distinct biosignature for this environment. Upon burial, they acquire a diffuse texture due to the expansion and contraction of gas-filled voids, and they present a geochemical signature rich in iron and titanium, which is due to the trapping of heavy minerals. We show that these intrinsic characteristics can be detected via μXRF analyses, and that they are distinct from buried abiotic facies such as cross-stratification and adhesion ripple laminations. We also designed and conducted an interactive survey using the Padre Island μXRF data to explore how different users chose to investigate a biosignature-bearing dataset via PIXL-like sampling strategies. We show that investigating biosignatures via PIXL-like analyses is heavily influenced by technical constraints (e.g., the XRF measurement characteristics) and by the variety of approaches chosen by different scientists. Lessons learned for accurately identifying and characterizing this biosignature in the context of rover-mission constraints include defining relative priorities among measurements, favoring a multidisciplinary approach to the decision-making process of XRF measurements selection, and considering abiotic results to support or discard a biosignature interpretation. Our results provide guidelines for PIXL analyses of potential biosignature on Mars.

A Conceptual Modeling Approach for Performance of Magnetohydrodynamic Drag During Planetary Entry

Future higher-mass Mars missions present numerous engineering challenges and will require significant technological development, particularly of the entry, descent, and landing systems. One such development concept utilizes magnetohydrodynamic interaction with the plasma created during hypersonic planetary entry for energy generation, drag augmentation, and heat-flux mitigation. In this study, a performance estimation methodology for magnetohydrodynamic drag augmentation during Mars entry compatible with conceptual design is developed. A demonstrative investigation utilizing the developed methodology is then conducted, and simulated trajectory results are presented for various entry vehicles and magnetic field strengths. The study results show potential for significant magnetohydrodynamic drag augmentation during hypersonic entry at Mars, with calculated effective ballistic coefficient- reduction factors of up to 4, across entry vehicles ranging in mass from 70 MT to 4 MT. These results show that magnetohydrodynamic drag augmentation can have comparable impact to significant aeroshell diameter increases and also suggest that it could prove an effective form of drag-augmentation control authority by varying the applied magnetic field.

Nano-interface engineering of NiFe2O4/MoS2/MWCNTs heterostructure catalyst as cathodes in the Long-Life reversible Li-CO2 Mars batteries

Lithium-CO2 batteries, a potential next-generation negative emission technology, are advanced energy storage devices with considerable interest in carbon neutrality for developing a sustainable environment. Additional challenges arise from the slow kinetics with poor reversibility in cycling performance and high overpotential of these batteries, limiting the further development of this technology toward large-scale implementation. Herein, we construct a NiFe2O4/MoS2/MWCNTs heterostructure nanomaterial catalyst as a cathode for Li-CO2 batteries function in the simulated Martian atmosphere (Li-CO2 Mars). The Li-CO2 Mars batteries with the proposed cathode exhibit excellent efficiency with a high discharge capacity of 26533.5 mAh g−1, a discharge plateau at ∼ 2.68 V, and high stability over 195 and 115 cycles with a limited capacity of 500 and 1000 mAh g−1, respectively. Computational studies demonstrate that improved CO2 adsorption with favorable discharge product growth using the heterostructure catalyst promotes the exceptional performance of the Li-CO2 Mars batteries consistent with the ex-situ experimental studies. The outcome of this study offers a novel approach to the design and construction of efficient multifunctional electrocatalysts, which can be used to develop sustainable and clean energy systems for both Earth and Mars missions.

Assessing the feasibility of laser induced breakdown spectroscopy for detecting nitrogen in martian surface sediments

Despite the detection of fixed nitrogen in meteorites and directly on Mars' surface, the abundance and distribution of nitrogen sequestered in the martian crust remains unknown. Given that nitrogen is a bioessential element that is required for the synthesis of amino acids, nucleic acids, and other organic molecules vital for life, this gap in knowledge is one of the most important challenges in constraining martian habitability. Laser-induced breakdown spectroscopy (LIBS) has the capability to detect N in natural rock samples and is available as a stand-off survey instrument on multiple currently active Mars rovers, creating an immediate opportunity to map the stratigraphic distribution of N within diverse depositional settings. However, little has been published regarding the detection of N with LIBS.To lay a foundation for N detection on Mars using LIBS, we synthesized a comprehensive suite of samples with variable amounts of nitrogen (as nitrate or ammonium) in either a Mars regolith simulant or a clay matrix. We present baseline spectra of N emission in Mars-relevant matrices and identify spectral interferences. Our results indicate that 17 diagnostic N emission lines are reliably detectable from mineral-bound N against a basaltic background, but only four lines exhibit sufficient sensitivity to be detected across a range of N concentrations and within all tested matrices. To elucidate optimized strategies for quantification, we present an iterative series of PLS models. We find that prediction accuracy is improved by restricting the compositional range of the training set, normalizing the data, subtracting baseline continuum emission, and simultaneously modeling the emission behaviour of multiple diagnostic N lines at once. We observe that the prediction uncertainty increases (worsens) from 8.4% to 29.9% if models are used to predict N in samples with a dissimilar matrix than those used during training, suggesting poor generalizability outside the training range. Consequently, future work should focus on developing a larger, more diverse training set that encompasses the range of N concentrations and phases expected to be encountered on Mars, which may be used to train generalizable models. Overall, this work demonstrates that LIBS is a promising tool for determining the abundance of N sequestered in martian surface materials and lays a foundation for future development.

Estimating Modal Mineralogy using Raman Spectroscopy: Multivariate Analysis Models and Raman Cross-Section Proxies

Abstract Raman spectroscopy is a powerful technique in the context of planetary exploration because it provides mineral identification, chemistry, and abundance information. For Raman spectrometers with large spot sizes, multiple mineral phases can be investigated via the collection of a single Raman spectrum. There is a lack of methodology for quantifying mineral species in mixtures due to independent signal strengths of different materials in Raman spectra. Two techniques are presented in this work for the quantification of common rock-forming minerals: partial least squares multivariate analysis and a novel approach called Raman cross-section proxies (numerical metrics associated with specific Raman features). This paper targets 20 mineral species relevant to the mineralogy of the planet Mars. Mineral end-member samples and 187 binary mineral-mineral mixtures (mixture of two distinct minerals) are used for multivariate modeling. Eighteen diamond-mineral mixtures are used to derive Raman cross-section proxies. Mineral abundance proportions are predicted for the binary mineral-mineral mixtures with known mineralogical content to evaluate the efficacy of the two quantitative methods. Technique performance is mineral-dependent. The root-mean-square error for unseen predictions (RMSE-P) using Raman cross-section proxies ranges from ±3.2-17.0 volume%. For the multivariate models, the cross-validated root-mean-square error (RMSE-CV) ranges from ±8.8 to 26.2 volume%. Although these error estimates are not directly comparable, they provide the most accurate error estimate currently available. Different scenarios may favor the use of one or the other of the two quantitative methods. This work provides fundamental groundwork that can be applied to common rock-forming minerals on terrestrial planets including Mars. Quantification of mineral abundances aids in answering critical geologic questions related to ancient primary and altered rocks as well as planetary processes and conditions.

Igneous Diversity of the Early Martian Crust

Mars missions and Martian meteorites revealed how complex the Martian crust is. The occurrence of both alkaline and sub-alkaline igneous rocks of Noachian age (>3.7 Ga) in Gale crater indicates diverse magmatic processes, with sub-alkaline rocks likely formed through the partial melting of hydrous mafic rocks, as commonly observed on Earth. The orbital discovery of excavated evolved igneous rocks scattered in Noachian terrains raise questions about the petrology of the ancient Martian crust, long thought to be basaltic. A possibly evolved crust beneath a mafic cover is supported by geophysical and seismic measurements from the Insight lander that indicate the bulk crust has a lower density than expected if it were homogeneously basaltic. If localized magmatic processes could form evolved terrains, the detection of abundant intermediate to felsic Noachian crustal exposures through remote sensing suggest regional- to global-scale processes that produced evolved crustal component(s) that are now buried below mafic materials. Due to the lack of centimetric to millimetric textural imaging and compositional measurements, the petrology of such crust is ambiguous. Future orbiter, rover, and aerial missions should focus on Noachian exposed regions exhibiting evolved crustal characteristics to unfold the petrology of the Martian crust and its formation.

Unveiling New Feminist Insights into the Inspiring Narrative of Women Pioneering India’s Accomplished Mars Mission in the Film Mission Mangal

The present research article delves into the transformative journey of women in society, with a particular focus on their education and emancipation, as depicted through the lens of cinema. In recent years, women have evolved from traditional roles to multifaceted individuals who actively shape their destinies. This transformation encompasses their education, as they gain access to knowledge and learning, and their emancipation, as they assert their rights and seek opportunities for personal and professional growth. Furthermore, this study explores the representation of these transformations in films, examining how cinema is a potent tool for educating and empowering women. “There are various works that deal with feminism through writings and movies which bring out the nature of women in a way that every woman can relate and reflect it with their daily lives.” (Shalini & Alamelu 2018) It investigates the portrayal of women’s lives and their journey towards self-realization and sheds light on the societal dynamics and challenges they encounter. Through cinematic narratives, women’s stories gain the potential to inspire and mobilize positive change, challenge existing norms and promote gender equality. The present study employs content analysis as the methodological approach, and this study seeks to provide a comprehensive analysis of the representation of women in “Mission Mangal” from a feminist viewpoint, revealing fresh insights into the portrayal of women’s roles and contributions in India’s Mars Mission exploration story.

Enhanced Interactive Rendering for Rovers of Lunar Polar Region and Martian Surface

Appropriate environmental sensing methods and visualization representations are crucial foundations for the in situ exploration of planets. In this paper, we developed specialized visualization methods to facilitate the rover’s interaction and decision-making processes, as well as to address the path-planning and obstacle-avoidance requirements for lunar polar region exploration and Mars exploration. To achieve this goal, we utilize simulated lunar polar regions and Martian environments. Among them, the lunar rover operating in the permanently shadowed region (PSR) of the simulated crater primarily utilizes light detection and ranging (LiDAR) for environmental sensing; then, we reconstruct a mesh using the Poisson surface reconstruction method. After that, the lunar rover’s traveling environment is represented as a red-green-blue (RGB) image, a slope coloration image, and a theoretical water content coloration image, based on different interaction needs and scientific objectives. For the rocky environment where the Mars rover is traveling, this paper enhances the display of the rocks on the Martian surface. It does so by utilizing depth information of the rock instances to highlight their significance for the rover’s path-planning and obstacle-avoidance decisions. Such an environmental sensing and enhanced visualization approach facilitates rover path-planning and remote–interactive operations, thereby enabling further exploration activities in the lunar PSR and Mars, in addition to facilitating the study and communication of specific planetary science objectives, and the production and display of basemaps and thematic maps.

Development and Analysis of Additively Manufactured Non-Pneumatic Tires for Mars Rover

Mars rovers are developed using the most sophisticated technology. Competitions such as the University Rover Challenge (URC), European Rover Challenge (ERC), and Anatolian Rover Challenge (ARC) encourage students to become acquainted and experienced with cutting-edge technology. This paper focuses on the development and analysis of a modified version of a non-pneumatic tire (NPT) for the MIST Mars rover “Phoenix 2.0.” Recent studies show that NPT has a good potential to replace conventional tires. To optimize the tire design for the rover, many design aspects are considered. The additive manufacturing process is used to fabricate the tire model to ensure the proper geometrical shape and usage of material. Later, a static structural analysis is conducted to investigate the stress and deformation of the tire that it may experience during rover operation. The developed deformation and stress in this analysis are well protected by the honeycomb structures that are optimized from many design attempts. The result shows a positive indication of meeting the desired criteria that eventually results in the fabrication of the tire and participation in the ARC competition. This research will inspire others to contribute to the advancement of NPT in various circumstances where pneumatic tires perform inadequately.

Retrieval of Ar, N2, O, and CO in the Martian Thermosphere Using Dayglow Limb Observations by EMM EMUS

AbstractThe Emirates Ultraviolet Spectrometer (EMUS) onboard the Emirates Mars Mission (EMM) Hope probe images Mars at wavelengths extending from approximately 100 to 170 nm. EMUS observations began in February 2021 and cover over a full Mars year. We report the first limb scan observations at Mars of ultraviolet emissions Ar I 106.6 nm, N I 120 nm, and carbon monoxide (CO) Fourth Positive Group (A − X) band system excited by electron impact on CO. We use EMUS limb scan observations to retrieve number density profiles of argon, molecular nitrogen, atomic oxygen, and CO in the upper atmosphere of Mars from 130 to 160 km. CO is a sensitive tracer of the thermal profile and winds in Mars' middle atmosphere and the chemistry that balances CO2 in the atmosphere of Mars. EMUS insertion orbit special observations demonstrate that far ultraviolet limb measurements of the Martian thermosphere can be spectroscopically analyzed with a robust retrieval algorithm to further quantify variations of CO composition in the Martian upper atmosphere.

Incipient Dissolution of Emplaced Forsterite and Fayalite Records the Effects of Climate, Mineral Composition, and Crystallographic Orientation

To investigate the effects of environment, composition, and crystal orientation on incipient surface alteration of forsterite and fayalite in a natural environment, polycrystalline forsterite and fayalite samples were emplaced in Mg/Fe-rich and Al-poor ultramafic soils under subarctic (Tablelands in Newfoundland, Canada; 3.9 ⁰C and ∼120 cm precipitation/year), Mediterranean (Klamath Mountains, California;≤12.8 ⁰C and ∼101-118 cm precipitation/year), and desert (Pickhandle Gulch, Nevada; ∼14.1 ⁰C and ∼14.4 cm/year) climates for one year. Incipient alteration after one year was examined using scanning electron microscopy, atomic force microscopy, electron backscatter diffraction, X-ray photoelectron spectroscopy, and visible and near-infrared reflectance spectroscopy.Alteration features on forsterite surfaces included flat-bottomed pits with steeply dipping walls likely developing on grain faces and representing surface retreat of individual grains and lining features likely developing along grain boundaries. Mg-leached surface layers formed under acidic to slightly alkaline conditions while Mg-enrichment was observed under alkaline conditions. Flat bottomed pit formation preferentially occurs on surfaces within 30° of perpendicular to the b-axis (on the [010] plane) of the olivine crystal lattice. Depth of flat-bottomed pits on forsterite surfaces follows the order Klamath Mountains > Tablelands >> Pickhandle Gulch, reflecting the importance of environmental conditions. Warm, wet, and relatively acidic conditions enhanced forsterite dissolution over cold, wet, and slightly alkaline conditions, with minimal alteration observed under hot but arid and alkaline conditions. Greater surface roughness on flat-bottomed pit floors on Klamath Mountain forsterite surfaces are consistent with less-saturated soil-pore water reaction conditions.In contrast, fayalite disks buried in the Klamath Mountains show no evidence for etch-pit formation despite the warm, wet, and slightly acidic conditions. Elevated Fe/Si ratios from X-ray photoelectron spectroscopy measurements and evidence of M-OH bonds in visual and near infrared spectra are consistent with formation of a Fe-enriched hydroxylated layer limiting fayalite surface area available for water-rock interaction and retarding fayalite dissolution during aqueous alteration under oxidizing conditions. These results differ from previous laboratory experiments that show enhanced dissolution of fayalite relative to forsterite, showing the effect of natural, oxic, unsaturated weathering zones. These results will be helpful for interpreting observations of this widely studied mineral, including from the planet Mars.

Biomimetic lizard robot for adapting to Martian surface terrain

The exploration of the planet Mars still is a top priority in planetary science. The Mars surface is extensively covered with soil-like material. Current wheeled rovers on Mars have been occasionally experiencing immobilization instances in unexpectedly weak terrains. The development of Mars rovers adaptable to these terrains is instrumental in improving exploration efficiency. Inspired by locomotion of the desert lizard, this paper illustrates a biomimetic quadruped robot with structures of flexible active spine and toes. By accounting for spine lateral flexion and its coordination with four leg movements, three gaits of tripod, trot and turning are designed. The motions corresponding to the three gaits are conceptually and numerically analyzed. On the granular terrains analog to Martian surface, the gasping forces by the active toes are estimated. Then traversing tests for the robot to move on Martian soil surface analog with the three gaits were investigated. Moreover, the traversing characteristics for Martian rocky and slope surface analog are analyzed. Results show that the robot can traverse Martian soil surface analog with maximum forward speed 28.13 m s−1 turning speed 1.94° s−1 and obstacle height 74.85 mm. The maximum angle for climbing Martian soil slope analog is 28°, corresponding slippery rate 76.8%. It is predicted that this robot can adapt to Martian granular rough terrain with gentle slopes.

Numerical investigation on cooling performance and control effect of a novel evaporation-driven cooling unit for Mars extravehicular space suit application

The special environment of Mars brings new challenges to the thermal control of spacecraft on Mars missions. The outstanding advantages of water evaporation cooling technology make it promising for use in the thermal control system of the Mars spacecraft. This paper proposes a novel concept of evaporation cooling hardware that integrates heat collection, heat transfer and heat rejection, namely evaporation-driven cooling unit. The evaporation-driven cooling unit has a simple structure, high evaporation efficiency and the potential to simplify the system topology. Furthermore, an expert hierarchical coordination control strategy applied to the Mars extravehicular space suit cooling loop with an evaporation-driven cooling unit as its heat sink is proposed. The dynamics model of this cooling loop is also constructed using the lumped parameter method. The numerical results have shown that the expert hierarchical coordination control strategy can achieve precise temperature control and reduce the water consumption of the system. The average water consumption rate during extravehicular activity is 0.6975 kg/h when the mean heat load is 572 W (including member metabolic heat and electronic waste heat). Compared to the open-loop case with the same input heat load, a typical extravehicular activity lasting 8 h will save about 11.5 g water if the expert hierarchical coordination control is applied. The proposed evaporation-driven cooling unit will provide more choices for heat rejection of extravehicular space suits. It is expected that the evaporation-driven cooling unit and expert hierarchical coordination control have potential applications in thermal control systems for other space vehicles in near-Earth orbit, on the surface of the Moon and Mars.

Multiphysics and multi-scale design and analysis of nuclear thermal propulsion pellet bed reactor based on spherical cermet fuel element

Due to the advantages of high thrust and high specific impulse, nuclear thermal propulsion (NTP) is a preferred near-term rocket engine technology for future Mars missions. This article introduces the reactor design based on spherical cermet fuel element, with the aim of studying the feasibility of applying this new fuel in NTP system. First, design requirements are determined based on the unique features of NTP. In terms of neutronics, the effect of rocket launch accidents and fuel loss caused by high-temperature hydrogen are considered. Thermal hydraulics refer to the requirements of NASA's Mars Design Reference Architecture 5.0 (DRA 5.0) for impulse, thrust, and thrust to weight ratio. Second, based on the requirements above, the optimal reactor configuration parameters are obtained with the goal of maximizing the thrust to weight ratio: reactor radius 51.1 cm, height 106 cm, aspect ratio 1.04, reflector 13 cm, and reactor mass 3940 kg. Finally, the performances of the optimal reactor design are analyzed. The neutron spectrum shows a characteristic of fast neutron spectrum, and fuel loss analysis shows that the core can withstand a fuel mass loss of about 4 wt%. In addition, the core axial and radial power distribution are calculated, with an overall power peak factor of 1.26. The thermal hydraulic calculation provides a range of core operating conditions that satisfy the design requirements of DRA 5.0 and temperature, with power of 620 ∼ 950 MW and flow rate of 16 ∼ 24 kg/s. Compared with the ANL200/2000 reactor using prismatic cermet, it has the advantage of higher specific impulse. The main disadvantage is the large pressure drop, which prevents it from being applied to the scenarios of high power and high thrust. Therefore, for NTP reactor using spherical cermet elements, it should be applied to low to medium power scenarios.

The Data Compression Method and FPGA Implementation in the Mars Rover Subsurface-Penetrating Radar on the Tianwen-1 Mission

Since Mars is far away from Earth, the propagation delay between Mars and Earth is very large. To ensure the effective use of the link transmission bandwidth, China’s first Mars exploration mission has put forward a demand for data compression for all scientific payloads. The on-board mature algorithms for data compression are mainly focused on optical images and microwave imaging radar applications. No articles have been published on data compression methods that are applied to subsurface-penetrating radar. Based on the background of this application, this paper proposes a logarithmic lossy compression algorithm which can meet the mission requirements for high compression ratios of 4:1 and 2.5:1. Its compression error is less than that of the block adaptive quantization (BAQ) algorithm. The algorithm is not only easy to implement on field-programmable gate array (FPGA) platforms, but also offers simple ground decompression and fast imaging. The experimental results show that high compression ratios of 4:1 and 2.5:1 can be realized, even if the data in and between traces do not have a strong correlation. And its relative error is less than 2%, which is a new type of high-efficiency data compression method that can be implemented on-board to meet with the demand of subsurface penetrating radar.

Spring Less Suspension using Rocker Bogie Mechanism

The rocker bogie mechanism is a type of suspension system commonly used in robotic vehicles, particularly in space exploration rovers like NASA’s Mars rovers. Unlike traditional spring-based suspensions, the rocker bogie mechanism relies on a system of pivoting joints and linkages to maintain stability and traction over uneven terrain. This mechanism allows the vehicle to traverse rough surfaces by distributing weight and adjusting wheel positions to accommodate obstacles. Its abstract nature lies in its ability to provide stability and mobility without relying on springs, making it well-suited for navigating challenging environments such as rocky terrain or steep slopes. Overall, the rocker bogie suspension system is well-suited for applications where stability, mobility, and reliability are paramount, making it a preferred choice for planetary exploration missions and other off-road vehicles operating in rugged terrain

Coarse‐Grained Ripples Investigated by the Opportunity Rover on Meridiani Planum, Mars

AbstractAeolian coarse‐grained ripples have been found in all regions investigated by Mars rovers: Meridiani Planum, Gusev crater, Gale crater, and Jezero crater. Therefore, it can be assumed that coarse‐grained ripples are one of the most common landforms on Mars. Studying their formation and evolution gives us the opportunity to determine past and current wind patterns. They are also crucial for understanding the formation and evolution of larger aeolian bedforms. Of all locations studied in situ on Mars, coarse‐grained ripples in extensive (∼100 km2) ripple fields were found only on Meridiani Planum. As coarse‐grained ripples on Mars are not well characterized in the literature, in this work, the morphometry, morphology, spatial distribution, and orientation of coarse‐grained ripples investigated along the 45 km long traverse of the Opportunity rover were analyzed. The obtained results allowed for a more precise definition of coarse‐grained ripples and for distinguishing three classes of coarse‐grained ripples on Meridiani Planum: small, medium, and large. The coarse‐grained ripple activity on Meridiani Planum is now limited due to low material supply, and the relatively strong induration of the ripple surfaces. Even though most of the coarse‐grained ripples on Meridiani Planum were formed thousands of years ago, some smaller coarse‐grained ripples were formed by modern winds.