CSCE 221 Culture Assignment 4
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Localization of multiple unknown transient radio sources using multiple paired mobile robots with limited sensing ranges
Chang-Young Kim, Dezhen Song, Yiliang Xu
Hostile sensor network search and destroy
Localization:
- triangulation
- time of arrival
- Radio frequency localization (received signal strength)
Problems we have with Hostile networks (vs. freindly) Signal source anonymity Short transmission duration Dynamic transmission patterns Unknown network size Perspective limit of robots
Constraints:
- LImited sensing range
- Variable transmission powers
Assumptions
- Centralized control
- Free 2D space
- Short and light network traffic
- Circular radiation pattern
- Stationary radio sources
Deriving probability of location
Sensor layer (should output probability), SPOG, and Motion planner
Three types of paired robots:
- Both receive signal
- one receives signal
- Neither receive signal (no information)
Product of information from different sources at different time causes probability to converge.
Pair distance must be far enough to triangulate source, but close enough to overlap a little
- PRWA triangulated fastest
Approximate Characterization of Multi-Robot Swam "shapes" in Sublinear Time
Lantau Liu, Klappi, et al.
Can an individual know the shape of the swarm?
- How long/wide is the network (geodesic diameter)?
- How many hops (geodesic distance) are necessary to get from one end to the other.
Problems:
- Distributed (everyone depends on everyone else)
- Local sensing and communication
- For a very large swarm size , becomes too expensive
Vocabulary: Sublinear: less than Path distance: sum of edge length along path
Boundary detection:
- outer edge of swarm (peripheral agents) Measuring angles between individual and surrounding robots (obtuse)
- inside swarm (inner agents)
- initiate root agent on periphery
- recognize and count peripheral agents
- Follow trace of 1st traversal
- Traverse inner agents
- ...
Send a message to the middle of the swarm, pass it along the most "tangent" angle between robots to other side; count number of "hops" made
This is sublinear since the peripheral agents initiate the message, and the inner agents only transmit the message
Simulation on dense (high degree) and sparse (low degree) uniform distribution of agents
Utilizing Roadmaps in Evacuation Planning
Sam Rodriguez
Complex reaction and many agents; Trying to get to an exit
Small to large map-based algorithms for simple office buildings
Similar to pursuit-evasion problem: communication, sharing, environment knowledge
Agents don't have to exactly follow the path. Path can be optimized and simplified.
Agents can be directors (avoid this exit, avoid this area, etc)