  Conventional quadrotors received great attention in trajectory design and
fault-tolerant control in these years. The direction of each thrust is
perpendicular to the body because of the geometrics in mechanical design.
Comparing with the conventional quadrotor, a novel quadrotor named
quad-tilt-rotor brings better freedom in manipulating the thrust vector.
Quad-tilt-rotor augments the additional degrees of freedom in the thrust,
providing the possibility of violating the normal direction of the thrust in
the conventional quadrotor. This provides the ability of greater agility in
control. This paper presents a novel design of a quad-tilt-rotor
(quad-cone-rotor) whose thrust can be assigned along the edge of a cone shape.
Besides the inheriting merits in agile from quad-tilt-rotor, the
quad-cone-rotor is expected to take fault-tolerant control in severe dynamic
failure (total loss in all thrusts). We simulate the control result in a UAV
simulator in SIMULINK, MATLAB.
