1. The Hive is Hungry: Exploring Bee Colony Search and Foraging Behavior through Simulation Peter Bailis, Peter Lifland Harvard Robobees 11 Dec 2009

2. Overview Bee Colony Foraging Simulator – Behavior model derived from Seeley – Several simplifying assumptions: 2D world, no real physics, etc. – Many modeled features: Bee waggle dance communication semantics, flight inaccuracy, etc. Focus on scouting, food source allocation

3. Benefits CS182 (AI w/ Professor Nagpal) Final Project Colony Team – Reasonably complete search algorithm simulator – Robust platform for testing—many knobs – Potentially adaptable to helicopter simulation Search strategy analysis – Several surprising results, despite relatively simple agent behavior

4. How do bees work? Bees “advertise” food sources they've found to other bees through a “waggle dance” performed in the hive. – This is similar to local beam search. – Better source == longer dance Approximately 10% of bees without an assigned food source scout for new food sources “Optimizes” for maximum food gathered per energy

5. Our Approach Build simulator in Python (appx. 800 lines) Test scout strategies (exact methods are not known) – Random walk, random points, random world traversal, spirals Test food heuristics – Real bees basically choose randomly from dancing bees – What if we perturb this? Closest food, Greatest quantity of food, Furthest food, Balance of quantity and distance?

6. Demo

7. Spirals

8. Random Walk

9. Distance-Food Selection Metric

10. Furthest Flower Selection Metric

11. Results, cont. ProbabilisticBest FlowerClosest FlowerFurthest Flower Dist-Quantity Metric Random Walk64.68%82.85%79.77%82.46%80.47% Spirals96.31%100.00%97.17%98.09%95.79% Traverse World71.63%71.52%80.72%75.44%74.72% Random Points96.50%95.76%92.65%87.38%99.91% ProbabilisticBest FlowerClosest FlowerFurthest Flower Dist-Quantity Metric Random Walk39.65%69.35%75.14%74.17%84.27% Spirals82.75%85.14%80.41%89.98%100.00% Traverse World87.11%95.45%93.98%94.99%93.50% Random Points82.99%88.91%84.72%89.97%88.80% Normal World Food Scarce World

12. Fin Open source: http://code.google.com/p/beesim

13. References robobees.seas.harvard.edu Seeley, Thomas D. Wisdom of the Hive: The Social Physiology of Honey Bee Colonies. Cambridge, Mass: Harvard UP, 1995. Print.