The Crazy Lune - Simulation

			The Crazy Lune

Simulation

The simulation videos below display the results of our location algorithm for different paths the Astronaut takes. The length of the simulations is for the Astronaut's walk up to 2 Km.

The following is an outline of what each component of the simulation means:

Left Plot: Path of Astronaut in xy plane.
- Black dotted: path taken by Astronaut
- Blue x: actual position of Astronaut
- Magenta o: estimated position
- Red/black x: actual Tag position
- Black o: estimated Tag position
- red circle: range in which tags can be read
Right Plots:
Plots of x,y,z coordinate (blue) and its estimate (black) over time

Random Path

The above video displays the results of the algorithm when the Astronaut takes a random (or pseudo-random) path in x,y and z direction. This is one of the unpredictable scenarios, as all tags (and the lander) are aligned in a random path and therefore the dilution of precision varies. In this case too, the algorithm did a pretty good job and for a distance of 2 km it achieved an average estimate error under 10m.

Random Return Path

The above video displays the results of the algorithm when the Astronaut takes a random (or pseudo-random) path in x,y and z direction. He starts out in 2km distance to the lander and an already taken path with tags. This video demonstrates, how the algorithm bevahes under presence of already known information. One can see that the poisition estimate error is not anymore growing but getting smaller on the way back heading to the lander.

Linear Path

The above video displays the results of the algorithm when the Astronaut takes a linear path in x,y and z direction. This is the worst case, as all tags (and the lander) are lined up and therefore the dilution of precision is maximal. Even in this case, the algorithm did a pretty good job and for a distance of 2 km it achieved an average estimate error under 10m. In this simulation it is good to see how the tag position estimation gets improved over time.

Tuesday, December 8, 2009