A full authority helicopter control design based on differential flatness is presented. The concept of outer flatness is deployed for the design. The position dynamics and attitude dynamics are treated as the outer and inner systems respectively. The proposed design is based on an approximate model which is differentially flat, and then modified for the exact model. Given a desired trajectory i...

In this paper the attitude tracking problem is solved for a flexible spacecraft in the case of measurements of the variables describing the attitude error. Such a control could be applied in failure situations for recovering a spacecraft, so increasing the fault tolerance of the spacecraft control system and the success of the mission. The result is a dynamic controller capable of reconstructin...

Nonlinear tracking control of unmanned underwater vehicles (UUVs) in 6 degrees of freedom (DOF) is discussed. The 4-parameter unit quaternion is used in a singularity-free representation of attitude. Several control laws based on a generalized Lyapunov function for the attitude dynamics are derived, including feedback from the vector quaternion, the Euler rotation vector and the Rodrigues param...

Typical quadrotor aerial robots used in research weigh less than 3 kg and carry payloads measured in hundreds of grams. Several obstacles in design and control must be overcome to cater for expected industry demands that push the boundaries of existing quadrotor performance. The X-4 Flyer, a 4 kg quadrotor with a 1 kg payload, is intended to be prototypical of useful commercial quadrotors. The ...

Although analytic solutions for the attitude motion of a rigid body are available, for several special cases, a comprehensive theory does not exist in the literature for the more complicated problems found in spacecraft dynamics. In the present paper, analytic solutions in complex form are derived for the attitude motion of a near symmetric rigid body under the influence of arbitrary, but const...

It is well-known that the multiple sliding surface control was developed to eliminate the problem of ‘‘explosion of complexity’’ inherent in the celebrated backstepping method. In this paper, we extend the multiple sliding surface control method further for systems in nonlinear block controllable form. As an application of the proposed control scheme, the robust attitude control law was synthes...

based on dynamic modeling, robust trajectory tracking control of attitude and position of a spherical mobile robot is proposed. in this paper, the spherical robot is composed of a spherical shell and three independent rotors which act as the inner driver mechanism. owing to rolling without slipping assumption, the robot is subjected to two nonholonomic constraints. the state space representatio...

To date, most quad-rotor aerial robots have been based on flying toys. Although such systems can be used as prototypes, they are not sufficiently robust to serve as experimental robotics platforms. We have developed the X-4 Flyer, a quad-rotor robot using custom-built chassis and avionics with off-the-shelf motors and batteries, to be a highly reliable experimental platform. The vehicle uses tu...