A novel speed estimation approach with control system based on model reference adaptive control (MRAC) is presented for low cost brushless dc motor drives with low-resolution hall sensors. The back EMF is usually used to estimate speed. But the estimation result is not accurate enough at low speeds because of the divided voltage of stator resistors and too small back EMF. Moreover, the stator r...

In the design of six degrees freedom (6-DOF) flight simulation system, unmodeled dynamic, transient performance and steady-state system are generally concerned. Considering that model is highly nonlinear requires high response speed stability, this paper applies L1 adaptive controller to control platform. The has a low-pass filter in feedback loop avoid frequencies signals, required can be enha...

Over the past fifty years the size of computer applications, as gauged by any reasonable measure, has increased exponentially. In contrast, our cognitive capabilities for understanding have not changed. This discrepancy has forced us to look for more abstract representations of systems to reduce the number of elements we have to consider simultaneously in order to understand the system behavior...

Based on two successfully and widely used control techniques in many industrial applications under normal (fault-free) operation conditions, the Gain-Scheduled Proportional-Integral-Derivative (GS-PID) control and Model Reference Adaptive Control (MRAC) strategies have been extended, implemented, and experimentally tested on a quadrotor helicopter Unmanned Aerial Vehicle (UAV) testbed available...

The model reference adaptive control (MRAC) designed based on the fictitious reference iterative tuning (FRIT) approach in an on-line manner has recently been proposed. The FRIT method is an off-line control parameters tuning method so that the plant output could follow the prescribed reference model output from one-shot experimental input-output data with no need for help from plant model. The...

The main objective of adaptive control schemes is to produces reliable controllers under plant uncertainties, non-linearity and time varying parameters. Adaptation schemes are designed to cope with slow parameter changes; in addition, input signals are assumed to have frequency spectrum restricted to low frequency. In model reference adaptive control (MRAC) schemes, however, perfect model track...

In this paper, a novel Model Reference Adaptive Control (MRAC)-based hybrid control algorithm is presented for the trajectory tracking of a tri-rotor Unmanned Aerial Vehicle (UAV). The mathematical model of the tri-rotor is based on the Newton–Euler formula, whereas the MRAC-based hybrid controller consists of Fuzzy Proportional Integral Derivative (F-PID) and Fuzzy Proportional Derivative (F-P...

In one hand, the Model Reference Adaptive Control (MRAC) architecture has been widely used in linear adaptive control field. The control objective is to adjust the control signal in a stable manner so that the plant’s output asymptotically tracks the reference model’s output. The performance will depend on the choice of a suitable reference model and the derivation of an appropriate learning sc...

We introduce a colored coalescent process which recovers random colored genealogical trees. Here a colored genealogical tree has its vertices colored black or white. Moving backward along the colored genealogical tree, the color of vertices may change only when two vertice coalesce. The rule that governs the change of color involves a parameter x. When x = 1/2, the colored coalescent process ca...