Pressurized Rover Research Articles

Shielding factors for a fission-powered mars exploration rover

Background: With the advances in compact fission power systems and Stirling converters, the efficiency and portability of electrical energy production systems has increased substantially thanks to NASA’s Kilopower project. These 1-10 kWe-class reactors are compact enough to be transportable by pressurized rovers, allowing an extended human reach across the surface of Mars to produce scientific data at a rate that greatly surpasses the rate of robotic rover data collection. If rovers were to harness fission power while mobile, it is possible for near-limitless range. This capability could allow one crew on Mars for under a “Conjunction” class mission as outlined in NASA’s Mars Design Reference Architecture (DRA) 5.0 to visit many geological sites of interest instead of requiring additional landings to explore distant features of the Martian surface. This study explored the parameters that affected the mass of the shielding required to protect the crew against a fission reactor embedded in the chassis of a pressurized rover. Methods: An analytical approach was devised to estimate the required mass of a hypothetical solid tungsten shield under various conditions. Results: Power levels below 3.4 kWe were found to be impractical for rover applications. Between 3.4 kWe and 10 kWe would be able to recharge the rover without returning to base camp. The increase in shielding mass from a 3.4 kWe reactor and a 10 kWe reactor was 6%. The reduction between a 10 kWe reactor at 3 m and 6 m was 7%. Varying the shield thickness in accordance with astronaut activities resulted in a 19% reduction. Powering the reactor off before exiting the vehicle resulted in an additional 65% reduction. Conclusions: Knowledge of the crew activities and locations had the greatest impact on the required shielding mass and the mission activities should be well-understood before finalizing a shield design.

(Keynote) Electrochemical Devices for Lunar Exploration - JAXA's Concept

Japan has decided to participate in the space exploration program "ALTEMIS program" proposed by US. One of the manned mission, Lunar surface exploration using rover (vehicle), is also involved in this program and Japan has started to develop it with JAXA and several companies and planned to be operational by the end of the decade, probably in 2029. The ultimate goal of the project is to help humanity live on the moon by 2040, and eventually on Mars. These plans are summarized in Fig. 1.This project surely supports the resources exploration on the moon as in-situ Resources Utilization(ISRU). The Lunar Cruiser, which alludes to Toyota’s Land Cruiser <https://hypebeast.com/tags/Toyota-Land-Cruiser> SUV, is essentially a fuel-cell-powered mobile laboratory that features living quarters, workstations, and cutting-edge scientific instruments. The pressurized rover is expected to have a “lunar-surface cruising range of more than 10,000 km.” Now, other automobile companies like Honda and Nissan might collaborate with all Japan projects.They have since then been creating virtual reality visualizations, conducting simulations, telecommunication systems for automatic operation and building full-scale models with photovoltaic power generation, advanced battery, and fuel cell. This presentation mainly focuses the energy and electrical system design. Figure 1

Dual rover human habitation field study

For the last 3 years, the National Aeronautics and Space Administration (NASA) has been testing a pressurized rover prototype in the deserts of Arizona to obtain human-in-the-loop performance data. This year's field trial consisted of operating two rovers simultaneously while embarking on two 7-day flight-like exploration missions. During the 2010 Desert Research and Technology Studies (DRATS) at Black Point Lava Flow and SP Mountain in Arizona, NASA human factors investigators, in cooperation with other engineers and scientists, collected data on both the daily living and working within and around the Space Exploration Vehicle (SEV). Both objective and subjective data were collected using standard human factors metrics. Over 305h of crew habitability data were recorded during the field trial with 65 elements of habitation examined. Acceptability of the vehicles over the course of the missions was considered satisfactory by the majority of the crews. As with previous testing, habitation was considered acceptable by the crews, but some issues concerning stowage, Waste Containment System (WCS) volume, and sleep curtains need to be considered for redesign for the next generation vehicle.

NASA Desert RATS 2010: Preliminary results for science operations conducted in the San Francisco Volcanic Field, Arizona

The National Aeronautics and Space Administration (NASA) is working with international partners to develop the space architectures and mission plans necessary for human spaceflight beyond Earth orbit. The Apollo missions to the Moon demonstrated conclusively that surface mobility is a key asset that improves the efficiency of human explorers on a planetary surface. NASA's Desert Research and Technology Studies (Desert RATS), a multi-year series of tests of hardware and operations carried out annually in the high desert of Arizona, has tested a crewed pressurized rover concept referred to as the Space Exploration Vehicle (SEV). During NASA's Desert RATS 2010, four 2-person crews driving two SEVs collectively conducted 12 days of field exploration in the San Francisco Volcanic Field in northern Arizona. They collected 461 samples, with a total mass of 161.2kg, on 70 simulated extravehicular activities (EVAs). Each SEV crew traveled over 60km during their field explorations. This paper illustrates where the actual field sites, or ‘science stations’, were located, provides a brief description of the types of samples collected at each station, and highlights some of the more interesting sites. Most of the geologic samples collected at Desert RATS 2010 were well documented at the site of collection, and upon delivery to the Johnson Space Center the samples were given a preliminary examination. The samples are available for further study by interested researchers developing scientific instruments for use on the surfaces of the Moon and Mars, or for geological investigations of the San Francisco Volcanic Field.

Determining Window Placement and Configuration for the Small Pressurized Rover (SPR)

A natural component to driving any type of vehicle, whether Earth-based or space-based, is visibility. In its simplest form, visibility is a measure of the distance at which an object can be seen. The National Aeronautics and Space Administration (NASA) have human factors guidelines for the Space Shuttle and the International Space Station (ISS) windows, in terms of ergonomics and safety. However, there is little research with respect to lunar vehicles. The goal of the current study was to obtain preliminary human-in-the-loop data on window placement and configuration for the small pressurized rover (SPR). Nine participants evaluated multiple areas along the vehicle's front “nose”, while actively maneuvering through several lunar driving simulations. Subjective data was collected on areas of necessity, frequency of views, and placement/configuration of windows. Results indicated a desire for large field-of-view windows spanning the front of the vehicle with slightly reduced window areas for the lower front, lower corners, and side views.

A Comparison of the Unpressurized Rover and Small Pressurized Rover during a Desert Field Evaluation

To effectively explore the lunar surface, astronauts will need a transportation vehicle which can traverse all types of terrain. Currently, the National Aeronautics and Space Administration's (NASA) is investigating two lunar rover configurations to meet such a requirement. Under the Lunar Electric Rover (LER) project, a comparison study between the unpressurized rover (UPR) and the small pressurized rover (SPR) was conducted at the Black Point Lava Flow in Arizona. The objective of the study was to obtain human-in-the-loop performance data on the vehicles with respect to human-machine interfaces, vehicle impacts on crew productivity, and scientific observations. Four male participants took part in four, one-day field tests using the exact same terrain and scientific sites for an accurate comparison between vehicle configurations. Subjective data was collected using several human factors performance measures. Results indicate either vehicle configuration was generally acceptable for a lunar mission; however, the SPR configuration was preferred over the UPR configuration priminarly for the SPR's ability to cause less fatigue and enabling greater crew productivity.

Determining Window Placement and Configuration for the Small Pressurized Rover (SPR)

A natural component to driving any type of vehicle, whether Earth-based or space-based, is visibility. In its simplest form, visibility is a measure of the distance at which an object can be seen. The National Aeronautics and Space Administration (NASA) have human factors guidelines for the Space Shuttle and the International Space Station (ISS) windows, in terms of ergonomics and safety. However, there is little research with respect to lunar vehicles. The goal of the current study was to obtain preliminary human-in-the-loop data on window placement and configuration for the small pressurized rover (SPR). Nine participants evaluated multiple areas along the vehicle's front “nose”, while actively maneuvering through several lunar driving simulations. Subjective data was collected on areas of necessity, frequency of views, and placement/configuration of windows. Results indicated a desire for large field-of-view windows spanning the front of the vehicle with slightly reduced window areas for the lower front, lower corners, and side views.

First Mars outpost power systems

Research into potential power systems for the First Mars Outpost (FMO) was performed. The author examined a representative mission architecture which was developed by NASA to determine power system requirements. Power system options including nuclear, isotope, photovoltaic (PV), chemical heat engine, and regenerative fuel cell (RFC) concepts were identified for potential Mars surface applications. A top-level characterization study was conducted to determine power system mass and area for each application. It is seen that PV systems are generally not suited for Mars surface applications due to the large surface area required and higher mass than a closed Brayton cycle SP100 reactor system. A reactor is currently being considered by NASA Lewis Research Center to provide power for base architectures including an ISRU (in situ resource utilization). An oxygen/methane powered heat engine would provide 40 kWe of emergency power for the habitat. A dynamic isotope power system (DIPS) is the current choice for a long-duration pressurized rover due to the excessive size of a PV/RFC system and higher mass of a heat engine system. DIPS has advantages for other low power systems due to its neatly immediate availability and flexibility (night or day power; no recharging required). >