The project consisted of five work packages, two of which were devoted to pursuing the project milestones and deliverables (WP1&WP2).
In work package WP1, theoretical approaches to entrainment, oscillator models and CPG architectures were compared. A new oscillator model was developed, based on the commonly used Matsuoka oscillator, but with added nonlinearity to promote flexibility. Multi-objective evolution was used to generate a diverse population of controllers that were interfaced with virtual quadrupeds. The phenomenon of spontaneous entrainment was studied by introducing rhythmic input to the network. Emergent properties of the CPG networks were analysed, with the result that sensitivity of gait frequency to input was predictive of entrainment ability. Complex inputs were also analysed using real musical excerpts, with the finding that pulse clarity partially predicted entrainment performance.
In work package WP2, a virtual hexapod was created from an open source design, with the controller using the same CPG modules as the quadruped in WP1. The controller evolution was repeated for these virtual hexapods. A morphology-agnostic algorithm was designed to learn new movement patterns during robot-to-robot interaction, and tested on a heterogeneous population of quadrupeds and hexapods. It was found that entrainment ability was mainly learner dependent, and that the learning scheme improved stability of movement compared to pure entrainment. A prototype of the hexapod design was also built and interfaced with an evolved controller, and was used to demonstrate entrainment to simple rhythms.
These results were detailed in two open-access peer-reviewed articles, two conference papers and two Erasmus project reports. The results were disseminated at three workshops in the host country and four international conferences and workshops.
