Simulation: Rendezvous without Coordinates

Jingjin Yu      Steven M. Lavalle      Daniel Liberzon

The University of Illinois at Urbana-Champaign

Supported in part by the DARPA SToMP program (DSO HR0011-07-1-0002)

[TAC submission]

To play around:

  • Input the number of agents,
  • Click on either the 'make rendezvous' or the 'make diverging' button,
  • Click on the 'launch simulation' button, watch, and enjoy!

Please note that the above semi-automated process set the parameters loosely. If you have read the paper and want to explore more, here are the brief meaning of the parameters (although 'time step' is counted in seconds, it is only relative; 'UI update delay' is in actual seconds):
  • number of agents: Total number of agents in the system initially.
  • initial range: Length, in units, of the bounding square of the simulation window.
  • line speed: Line speed, in units, of all the agents that are moving.
  • angular velocity: Angular velocity when an agent is turning.
  • threshold angle: Half of the vehicle windshield span.
  • time step: Time step between system updates. The unit is (virtual) seconds of the agent system. Each update calculate where an agent should be based on its last control input and update whether it should be turning).
  • steps per UI update: Number of time steps between screen updates.
  • UI update delay: To avoid occupying CPU and also make simulation more watchable, this is the time in actual seconds between each UI update (as well as system updates).
  • merge radius: Minimum distance, in units, between two agents when an agent can merge with its target. By default this is set to be very small (0.01) to prevent merging so that the behavior of the whole system can be better observed. Making it larger (0.5) will cause merging to happen earlier.
  • full/cyclic: Cycle plus branches or cycle only. For the "full" choice, reassignment and changing target to closer agent are always performed when the conditions are satisfied (therefore the "make rendezvous" and "make diverging" buttons do not apply to this case). Note that, having a reasonably large merging radius is also necessary to guarantee reassignment. Very small (for example, the default value) merging radius can potentially lead to several clusters of agents as stable configuration.
  • function: The function to be used for plotting.
Closing the browser will close all simulation windows.