Enhancement of Spatial Orientation Capability of Astronauts on the Lunar Surface

1. Original aims of project

The overall goal of this project was to develop a Lunar Astronaut Spatial Orientation and Information System (LASOIS) able to reduce spatial disorientation risks during future manned lunar landing missions. The detailed objectives were to: 1) Investigate methods for removal and/or alleviation of astronaut disorientation in a lunar surface operations setting by using integrated information technology along with psychological and cognitive research on spatial orientation and navigation; 2) Develop the LASOIS system; and 3) Train astronauts to enhance their LASOIS-supported spatial orientation capabilities in a simulated lunar environment. Supported by LASOIS, astronauts engaged in lunar surface operations will be capable of overcoming disorientation caused by microgravity and the altered visual environment through spatial information provided by the Earth-based control center after data collection by a coordinated group of lunar orbital, descent, and ground-based sensors. The spatial-orientation strategies, technology, and training program here developed will allow astronauts to successfully complete complex mission scenarios where spatial operations and efficient interactions and communications are required among the Earth-based control center, lander(s), lunar vehicle(s), outposts, and astronauts. This capability is critical for future lunar operations, which are expected to cover an extensive region.

2. Key findings of the project

The following summarizes the key findings, research activities, and results over the three years of the project:

1. Investigation of the typical scenarios and constraints of EVA (Extra Vehicular Activity) operations experienced by astronauts during previous lunar missions to provide a baseline for the design of LASOIS;
2. Investigation of different astronaut locomotion patterns (including walking, jogging, and hopping) as observed on the lunar surface during Apollo mission surface operations to develop new astronaut spatial orientation capabilities through LASOIS;
3. Design and development of LASOIS prototype. In LASOIS prototype Version 3.0, we miniaturized the hardware system using a palm-sized computer and display, stabilized the communication system by replacing wireless data transfer with a secure cable system, and improved sensor integration strategies in the developed software for real-time operation and improved performance. LASOIS prototypes were tested in multiple lunar-like field sites, simulated lunar EVA scenarios, and differing step patterns. The field experiment in the third year successfully supported a 6.1 km traverse with only a 2.42% relative disclosure error based on an experiment simulating the Apollo 14 traverse.
4. Development of an additional star tracker technology to be used as a navigation solution in emergencies to improve the flexibility and robustness of the navigation system; and
5. Execution of additional research activities including a study of lunar surface beacon systems for astronaut localization, investigation of display modes most suitable for terrestrial environments for navigation aids (plan view, bird's-eye view, wingman view, pilot view), and training of subjects on how to use LASOIS.

3. Impact of the findings on the objectives of the proposal

According to the proposed schedule, the above-mentioned achievements have fulfilled the designated tasks for this project. We studied lunar EVA scenarios and astronaut locomotion patterns based on past Apollo missions to investigate the lunar environment and potential factors that contribute to astronaut disorientation. A LASOIS prototype was designed and developed to provide technical assistance to alleviate astronaut disorientation during EVA traverses. We designed and conducted field tests in multiple lunar-like environments based on lunar EVA scenario criteria such as terrain type, surface land cover, traverse distance, and step patterns, using test results to improve the prototype in both hardware and software efficiency. The final system has been miniaturized into a light-weight system with real-time operational control through the arm-mounted display unit. LASOIS has proven to be able to support a 6 km simulated EVA with only a 2.42% relative disclosure error. We have trained subjects to operate the system. We have tested various combinations of display modes based on psychological and psychophysical research techniques into spatial orientation and navigation to determine the best setting to enhance the spatial orientation capabilities of astronauts on the lunar surface. In addition, we developed a star tracker system to be used as an alternative localization system in case of emergency situations during lunar surface exploration.