The aim of this paper is to present the design of a novel omnidirectional Unmanned Aerial Vehicle (UAV) with seven uni-directional thrusters, called O 7 +. The paper formally defines the O + design for a generic number of propellers and presents its necessary conditions; then it illustrates a method to optimize the placement and orientation of the platform's propellers to achieve a balanced O + design. The paper then details the choice of the parameters of the O 7 + UAV, and highlights the required mechanical and electrical components. The resultant platform is tested in simulation, before being implemented as a prototype. The prototype is firstly static-bench tested to match its nominal and physical models, followed by hovering tests in multiple orientations. The presented prototype shows the ability to fly horizontally, upside down and at a tilted angle.