All Articles by Hai

7 Articles


Upon her return from a foraging flight a bee might behave quite strangely: she throws her body from side to side moving wildly over the comb surface. Others attend this performance and – after a little while – show up at her feeding site. The so called “waggle dance” informs nestmates about the existence and the location of valuable ressources like food and water – learn more about the waggle dance. Honeybees are the only species in the insect world showing an abstract – we might call it symbolic – communication.

More than 60 years after the discovery of the meaning of the dance many questions remain unanswered. How do the follower bees decode the dance? Which stimuli sent out by the dancer carry information and which are actually used by the receivers of the message?

Therefor, the research groups of Prof. Dr. Menzel (Institute of Neurobiology) and Prof. Dr. Rojas (Institute of Computer Science) are studying the dance communication in Apis mellifera bees by means of a robotic honeybee, aka the Project RoboBee.


Suppose a school of fishes suddenly turns. Who initated this turn? Was this leading fish acting first because of the topology of the swarm, him being closest to the cue? Or do individuals exist with a higher probability of leading? What properties do leaders have? Is it their looks, or their behavior that make the others follow?

Using a biomimetic fish robot we are able to test various hypotheses: we can make the Robofish thin or big, act risk-averse or adventurous, nervous or calm. Having full control over the hypothesis, experiments are perfectly reproduceable.

In the project RoboFish, as a joint project of Freie Universität Berlin (Rojas group) and Leibniz Institute of Freshwater Ecology (Krause group), we are developing a biomimetic fish swarm for the investigation of swarm intelligence in fish schools.


NeuroCopter is a joint project of the Biorobotics Lab and the Neuroinformatics group at Free University Berlin. Our goal is to control an autonomously flying robot with a brain simulation. We want to develop the neural control architecture for “high-level” tasks such as learning, memory and navigation. The design of this neural architecture will follow an insect model, the honey bee.

The robot will learn to navigate in previously unknown terrain by relying on sensory modalities of bees, i.e. measurements of stereoscopic optical flow, polarization of the sky, color and geometrical terrain features and odor detection. The central brain of the robot is equipped with a spiking neural network of deep architecture where learning is expressed locally by different forms of synaptic plasticity and metaplasticity, reinforced through external and internal rewards. The central network will compute behavioral decisions that drive low level motor plans.

The first version of the robot will rely on simulated neural circuitry; the final version will be equipped with neuromorphic electronics running a network of spiking neurons in hardware structures.


Bees have amazing cognitive capabilities. The scouts explore and learn the terrain and build up a highly detailed neuronal representation of the surrounding environment. Once back in the hive, locations are communicated to others by translating location information into body movements; a behavior known as waggle dance. In our experiments with a honeybee robot we noticed that some foragers seem to prefer certain nestmates in the process of decoding the dance. Do bees form stable “peer groups” throughout their lives? What determines that one bee becomes a “friend”?

In the past, answering those questions was very laborious. Biologists would sit in front of an observation hive, keeping track of single marked bees and take note with whom they dance. We are taking this analysis to the next level. We develop a system which allows tracking every single individual inside the hive. We use unique tags to mark each bee and develop a machine vision system to find every bee in the hive. We can then tell which bees are communicating one with whom and where and how long and so on. The analysis of the complete social network has never been done previously. We are happy to work with our partner Zuse Institut Berlin where all our data (~190 Terabyte) is stored and analyzed on supercomputers.

Tim Landgraf

In the near future, the capacity of man-made intelligent systems to communicate and collaborate will significantly change the way computing and control is organized. In biological systems, individual units often organize in groups, yielding various benefits for the individual. In social insects, many thousand individuals cooperatively exploit food sources, build or repair home structures, fend off enemies and accomplish a vast variety of tasks without central control. My group studies the mechanisms of collective intelligence in biological systems (mostly honeybees and guppies) via robots and machine learning methods. We also investigate how we can apply our findings in artificial systems to leverage the sensory, cognitive and motor capabilities of each individual for the group.