Now, I am sitting in this big Pavillion Ballroom waiting for Marco Dorigo to start his presentation. He is going to talk about “Self-Assembling in Swarm Robotics: The Swarm-bot Experiment”.
His group has built swarm-bots (s-bots). S-bot are small robots than can connect to each other and do things that a single robot cannot do.
The technological motivation for this work is: Robustness, Flexibility, Scalability
s-robot are 12cm.
Also I found out that Khepera is pronounced as Kepera.
The simulator they developed has different levels of abstraction as the model of the robot. One important problem for them was selecting the right level of complexity for the simulation of their robot.
To design robots’ controllers, they either hand-coded behavior-based system or evolved a neural network to do so. They did all designing in the simulator and then downloaded the result to the real robot.
The evolved a NN to do collective movement of a swarm of s-bots.
They used Perceptron and evolved their parameters using a simple ES method.
I missed (or maybe it is not mentioned) the observation space of the NN.
It seems that the resulted controller can work in different situations. For instance, it is scalable, can do coordinated movement with different initial formation of robots and etc.
Then they tried to evolve a controller for more complex tasks such as hole avoidance. They used a ground-hole detector for each robot and also a microphone to detect sounds. The action space is motion AND some sound. This sound can be used to communicate with other robots.
On going work:
-Functional shape formation
-Adaptive task allocation
-Evolution of recurrent neural nets for memory …
Finally, I asked about using ideas of learning (RL). He said that the main reason that they did not test it is the lack of resources (as each experiment takes a lot of time).
After the talk, I asked about the comparison of the reinforcement learning and evolutionary approach to design autonomous agents. He said that the main problem is that nobody is going to really compare different methods in the same robotic task because it is time-consuming (and people in the field are lazy (these are my words!)).
Well … I liked the talk. It was fun. More importantly, I really impressed by the results.
You may get more information the project’s website: Swarm-bots