1. Original aims of project
The overall goal of this project is to develop a Lunar Astronaut Spatial Orientation and Information System (LASOIS) that will reduce spatial disorientation risks during future manned lunar landing missions. The detailed objectives are:
1.1 To investigate methods for removal and/or alleviation of astronaut disorientation in a lunar surface operations setting by using integrated information technology, and psychological and cognitive research on spatial orientation and navigation.
1.2 To develop the LASOIS system.
1.3 To train astronauts to enhance their spatial orientation capability in a LASOIS-supported simulated lunar environment. Supported by LASOIS, astronauts will be capable of overcoming disorientation in lunar surface operations caused by microgravity and the altered visual environment through spatial information provided by the Earth control center and collected by a coordinated group of sensors from lunar orbit, descending path, and ground. The developed spatial orientation strategy, system and training will allow astronauts to have a systematic preparation for 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 lunar operations that will have an extensive traversing region (around 100km).
2. Key findings of the project
2.1 Based on the integrated sensor network established in the first year, we improved the approaches for processing and integrating spatial data collected by the integrated sensor network, and approaches for turning the vast amount of data from the integrated sensor network into necessary spatial-orientation information usable by lunar astronauts.
2.1.1 Further development and systematical evaluation of an Extended Kalman Filter (EKF) to integrate measurements from IMU, step sensor, and stereo cameras, the closure error of a loop traverse of more than one kilometer can be less than 4% of the traverse length (500 m) now.
2.1.2 Improvements of a Kanade-Lucas-Tomasi algorithm for astronaut navigation from video tracking, and explorations about how to utilize various spatial constraints for improving the computational efficiency of this algorithm. An algorithm can run in real-time mode now.
2.1.3 Development of a Star Tracker technology as a navigation solution in emergency to improve the flexibility and robustness of the navigation system. Preliminary finding is that the localization accuracy of this approach is 30 km, but the angle accuracy is about 1 degree.
2.1.4 Development of an approach for matching orbital and ground imagery based DEMs for initial localization of astronauts. The localization accuracy was 12m on Moses Lake data.
2.2 Design and development of LASOIS prototype 2.
2.2.1 Improving the precision, robustness and mobility of LASOIS through incorporating a tactical IMU, the redesign of the astronaut boot and on-suit package. Extensive field experiments show that LASOIS 2 can support long walks of more than 2 km.
2.2.2 Investigation on different on-suit sensor (IMU, step sensor, and stereo cameras) configurations for best navigation capability through extensive experiments.
2.2.3 A set of tests of the LASOIS 2 were performed at OSU. For example, a trajectory was derived using a tactical IMU and a step sensor. Comparing the derived trajectory to a trajectory determined using GPS, a disclosure of 4% was obtained (20 m over 500 m).
2.2.4 Two field tests for LASOIS 2 were conducted at NASA Plum Brook station on March 10, 2010, and at Black Point Lava Flow, Arizona, from June 10th to June 14th. We analyzed and summarized these experiments results as research reports for guiding further developments of the LASOIS prototype system.
2.3 Other research activities.
2.3.1 Study on lunar surface beacon systems for astronaut localization;
2.3.2 Investigations on display formats most frequently used in terrestrial environments for navigation aids (plan view, bird's eye view, wingman view, pilot view).
2.3.3 Training of subjects on how to use LASOIS 2, evaluating displays that the subject will wear when navigating the environment.
3. Impact of the findings on the objectives of the proposal
According to the proposed master schedule, the above mentioned achievements have fulfilled the designated tasks for the second year of this project. We conducted further tests and improvements of the developed technologies for spatial data processing, integration, and spatial information derivation and visualization. These improvements reduce the computational complexity, and improve the precision, reliability and robustness of the system to achieve real-time high-quality navigation information delivery. LASOIS 2 has been developed and tested. A spatial database containing data collected on all LASOIS test sites is being constructed including high-resolution satellite and ground imagery, videos, measurements from multi-sensory data, and ground truth measured by GPS and field survey. This database will be available to other NSBRI funded scientists and NASA researchers. All these results and experiences achieved in the second year will significantly contribute to the further research and development of LASOIS.
4. Proposed research plan for the coming year
4.1 Improvement of LASOIS 2 by integrating additional sensors (beacons) and considering different astronaut locomotion patterns in a micro-gravity environment.
4.2 Development of LASOIS 3 with real-time navigation capability, integrated on-suit navigation package, and robust data integration software for supporting 5 km long traverses.
4.3 Test LASOIS 3 in NASA or NSBRI led field analog testing campaign. 4.4 Explore and evaluate visualization approaches for effective delivery of the navigation information to astronauts on a small display. |