Steels' Martian Rovers

Update: There is now a new version of the rovers app which includes a plan editor and better simulator.

Below is a (buggy) simulation of Steels' martian rover experiment (without obstacles) which demonstrates that the subsumption architecture is a good way of quickly generating pretty looking simulations. The reset condition is when the simulation crashes, says a lot really....

What is it doing

Each black dot represents a martian rover which is trying collect rock samples on an unknown planet.
The blue dots represent interesting rocks which the rovers might want to sample
The yellow dot in the center represents the lander from which the rovers are launched, The lander transmits a radio beacon which the rovers can pick up and determine a bearing to. .
The red dots represent radioactive grains which may be picked up or dropped by the rovers

Each of the rovers follows a simple set of rules as follows:

#	Condition	Action
1	holding sample, at base	drop sample
2	holding sample, not at base	drop radioactive grain,move toward beacon
3	not holding sample, detect sample on ground	Pick up sample,move toward beacon
4	not holding sample, detect radioactive grain on ground	Pick up grain, move away from beacon
5	not holding sample, don't detect radioactive grain	Move in random direction

The conditions are evaluated in order and if a condition is met then the given action is applied.