  For legged robots to perform agile, highly dynamic and contact-rich motions,
whole-body trajectories computation of under-actuated complex systems subject
to non-linear dynamics is required. In this work, we present hands-on
applications of Horizon, a novel open-source framework for trajectory
optimization tailored to robotic systems, that provides a collection of tools
to simplify dynamic motion generation. Horizon was tested on a broad range of
behaviours involving several robotic platforms: we introduce its building
blocks and describe the complete procedure to generate three complex motions
using its intuitive and straightforward API.
