Control >> Cooperative transport

Cooperative transport

The following sections are devoted to various problem instances of the family of cooperative transport tasks. All instances have in common that a single object (hereafter also called the prey) shall be moved by a group of s-bots which are initially put in the objects' vicinity. The cooperation of several s-bots is required to move the prey.

Along with the problem instance, we altered the s-bot's capabilities of interacting with its teammates and the environment. In the simplest case, the s-bots are restricted to interactions via the environment or via their physical embodiment, since they do not perceive each other. On the contrary, in the most complex case, s-bots make use of binary signalling to communicate their status.

For each task, we employ an artificial evolution in order to shape solutions for the s-bots' control. The degree of human intervention in the design process is varied substantially. It ranges from providing the system with a the high level objective of the robot group, up to providing a decomposition of the task and control.

Transport by a team of two minimalist robots We describe an experiment about the transport of prey by a team of two minimalist robots in an arbitrary direction. It is shown that even if the s-bots are not capable of perceiving each other, they can interact with the environment in order to achieve cooperation. Transport of objects of different shapes and sizes This is about the problem to transport prey of different shapes and dimensions towards a target location. The evolved controllers perform robust with respect to different prey, and allow the group to transport the prey towards a moving target. Transport by swarms of blind and non-blind s-bots We detail an experiment in which we attempt to control a group of s-bots of which some s-bots are given the opportunity to localise the target, while the others (called the blind ones) are not. Unless no robot is able to localise the target, blind s-bots can be controlled to contribute to the performance of the group. For the best evolved solution the performance scales well with group size, making it possible to transport heavier prey by larger swarms of robots.

Control >> Cooperative transport