In this study, attitude control is proposed for helicopters with actuator dynamics. For the nominal helicopter dynamics, model-based control is firstly presented to keep the desired helicopter attitude. To handle the model uncertainty and the external disturbance, radial basis function neural networks are adopted in the attitude control design. Using neural network approximation and the backste...

the current study aimed to define some factors contributing to implicit attitude formation mainly in the social interaction context. an agent-based computer simulation of a society including autonomous agents and an attitude object was used to track the implicit attitude progress towards the object. the society could simulate the autonomic behaviors. we provided a complex adaptive system and ob...

Magnetometers are widely used for LEO small satellites attitude determination and control system. In order to estimate satellite dynamics and control attitude accurately, scale factor and bias of magnetometer must be estimated. In this study a linear Kalman filter (LKF) based algorithm for the estimation of magnetometer biases and scale factors is proposed. Proposed algorithms are simulated thr...

Neural networks are non-linear functional approximators, and natural candidates to be used in nonlinear systems control. Satellite nominal attitude control dynamics is an example of non-linear system where conventional control has been applied sucessfully since the early space age. However, conventional control like the PD (proportional and derivative of the error) can only guarantee robustness...

For autonomous helicopter flight, it is common to separate the flight control problem into an inner loop that controls attitude and an outer loop that controls the translational trajectory of the helicopter. In previous work, dynamic inversion and neural-network-based adaptation was used to increase performance of the attitude control system and the method of pseudocontrol hedging (PCH) was use...

In this paper we present a PID+ backstepping controller, as a solution to the problem of coordinated attitude control in spacecraft formations. The control scheme is based on quaternions and modified Rodriguez parameters as attitude representation of the relative attitude error. Utilizing the invertibility of the modified Rodriguez parameter kinematic differential equation, a globally exponenti...

-The attitude stabilization problem of a rigid spacecraft using control torques supplied by gas jet actuators about only two of its principal axes is considered. If the uncontrolled principal axis of the spacecraft is not an axis of symmetry, then the complete spacecraft dynamics are small time locally controllable. However, the spacecraft cannot be asymptotically stabilized to any equilibrium ...

The State-Dependant Riccati Equation method has been frequently used to design suboptimal controllers applied to nonlinear dynamic systems. Different methods for local stability analysis of SDRE controlled systems of order greater than two such as the attitude dynamics of a general rigid body have been extended in literature; however, it is still difficult to show global stability properties of...

The sparsely populated northern Sweden has been the main target area for regional policy efforts since the 1960s. A rich variety of regional policy measures have been launched over the years. However, despite this and a heavy expansion of welfare undertakings a significant depopulation has taken place. Also the first generation of EU Structural Funds show very weak structural impacts on develop...

Opinion dynamic models frequently assume an opinion to be a onedimensional concept and only sometimes vectors of opinions are considered. Contrary, psychological attitude theory considers an attitude to be a multidimensional concept, where each dimension is composed of beliefs and evaluative components. In this article we extend classic basic models of opinion dynamics such that they can captur...