MicroGravity Environments (Case Study)

Educational Need
In conversation with Professor Dava Newman in June, 2008, a fascinating story emerged. A female astronaut in the International Space Station got stuck. Because she was smaller than the other astronauts, her arms and legs were too short to reach the internal handholds and she was trapped, suspended in the Space Station’s weightless atmosphere. How to propel herself back to safe territory?

A similar problem could present itself in free space. If an astronaut lost power in her body jets, how could she maneuver herself back to the Station? Keep in mind that movement in space is non-intuitive and none of the inherited instincts that humans rely on would help. In micro-gravity there are six possible variables for propulsion comprised of 3 three degrees and 3 axes. One can do motions, translations and rotations about any of the three axes but it is not readily apparent what are the fastest and most efficient combinations.

Project Implementation
Prof Newman engaged her freshmen students in solving this puzzle. In specific, they needed to find out what physical movements an astronaut should make in micro-gravity in order to re-orient her body. They would also need to identify the principles of physics used to accomplish this. Several barriers prevented the students from tackling this challenge. Most importantly, the mathematical computations involved were far beyond the capabilities of incoming undergraduates. Therefore, Newman’s task was to present a learning opportunity which used practical applications of physics principles without requiring in-depth knowledge of calculus and engineering. Newman: “If the students could see the problem in an animation or visualization, we thought that would really motivate their learning.” Furthermore, a visualization would illustrate enough of the relevant variables so that students could … “understand and manipulate the physics without needing to know the underlying mathematics.” How do you represent a problem such as this visually? One obvious approach was through virtual reality. If an astronaut “avatar” (an on-screen robot) could be created that responded accurately to the laws of micro-gravity situations, the equations of motion could be demonstrated in real time. Professor Newman turned to Violeta Ivanova of OEIT for assistance.

Working with Ph.D. candidate Leia Stirling (who contributed the mathematical programming), Ivanova created the coding and authoring in X3D (the standard XML modeling language for 3D) to enable a visualization of astronaut motion in micro-gravity environments.

Within a few months, Ivanova’s on-screen animation was far enough along for Professor Newman to use as a demonstration during her lectures. The equations of motion and the principles of astronaut performance were crystallized in those few moments of animation. Imagine a visual representation of an astronaut in the next generation space suit, stylishly tight-fitting to allow greater freedom of movement, on the screen in front of you, a black background with a few reference points (but no hand-holds), and your keyboard and mouse determining how the astronaut will move.

Newman: “I’m trying to take some of their fundamental learning and knowledge and apply it to astronaut motion…in order to contextualize the physics that they would be interested in... and it’s explicitly the pedagogy that I’m going for in order to motivate further learning. In a few years, hopefully by the time they are seniors, they will understand the full-blown equation.“

Why is it important to understand the physics behind astronaut motion? In experiments involving actual astronauts in the space shuttle, Newman’s research group found a significant difference between astronauts who had received a tutorial on the theory behind micro-gravity motion and those who had not. The tutored group, like the non-tutored group, took the same number of tries to get to the target location. However, the tutored group was subsequently able to repeat the movement, while the non-tutored group could not. Reinforcing theory with practice resulted in quicker learning.

Next Steps
Prof Newman's next step will be to take the visualized animation of robot motion – the virtual reality representation – and evolve it into an actual simulator. Students will have access to the software and can experiment with selecting appropriate motions and velocities that will move the virtual astronaut as intended. Newman also wants to create a live, interactive simulation that allows students to experiment with different movements and see the often unexpected and undesirable results. Students will be able to make mistakes, learn from their mistakes, and also learn the physics principles. Ivanova, of OEIT, continues in collaboration with Professor Newman to complete the simulation phase of this project.