Angular displacement

About: Angular displacement is a research topic. Over the lifetime, 5102 publications have been published within this topic receiving 46081 citations. The topic is also known as: rotational displacement.

Suboptimal controller design for flexible launch vehicle based on genetic algorithm: Selection of the weighting matrices Q and R

Abstract: In this study, a suboptimal controller for the pitch plane motion of a flexible launch vehicle is presented. Three sensors for measuring the motion, angular position sensor, angular rate sensor and accelerometer, are considered and assumed to be at given positions on a rocket described by a ninth-order state-space dynamical model, including three bending modes. The weighting matrices with respect to the suboptimal control method, which are used to synthesize a performance index, are selected by the genetic algorithm. Additionally, in order to improve the robust performance of the flexible launch vehicle, various uncertainty combinations are predetermined and considered in the process of the genetic search. The simulation results indicate that both the rigid body and flexible mode response are desirable, and the control performance including the robust performance is better than that of the suboptimal controller with manual selection of the weighting matrices.

Angle measurement system

Abstract: Some aspects of the present disclosure relate to techniques for measuring an angular position of a rotating shaft. As will be described in greater detail below, some angle measurement systems of the present disclosure include at least two magnets that cooperatively rotate at different rates according to a predetermined relationship (e.g., a predetermined gear ratio). Two or more magnetic field sensing elements, which are often stationary, measure the directionality of the resultant magnetic field at different positions for a particular angular shaft position. Based on the directionality measured by the magnetic field sensing elements, the techniques can determine an absolute angular position of the rotating shaft, which can be greater than three-hundred and sixty degrees.

Device for measuring the angle of rotation or of the angular position of a rotating object

Abstract: An optical interferometer used for measuring the rotational angle or the anglular position of a rotating object, in which a path deflection is caused by means of the rotation of a reflector, the rotational movement of which is coupled with that of the object to be measured and thus is synchronous with its rotation. Furthermore, a laser beam is introduced into the interferometer. The path deflection caused by the rotation of the retro-reflector creates in the introduced laser beam varying interferences of defined wave length, which are proportional to the rotational angle of the reflector and of the object to be measured which drives it. Furthermore, the angular resolution is inversely proportional to the wave length of the laser beam.

Modeling and controller design of twin rotor system/helicopter lab process developed at PIEAS

Abstract: This report presents the modeling and controller design for a twin rotor system (TRS). This is a two input two output nonlinear system, having strong cross coupling between the inputs and the outputs. The task is to control the angular position (the azimuth angle and the elevation angle) of the system. Nonlinear equations of azimuth and elevation angles are derived in state space using Euler-Lagrange equations. The model is then linearized and the controller is applied to control both the angular positions simultaneously. Rotor forces are calculated experimentally. A set of model parameters for the system is also provided at the end.

Electronic angular measurement device

Abstract: The invention relates to an angular measurement device comprising a variable reluctance magnetic circuit comprising a fixed portion (3) associated with a coil (2) and at least a moving element (4) attached to a part (5) rotating in front of the fixed portion, the angular position of which is to be detected, comprising: means (I) for integrating the voltage across the coil, means for measuring the instantaneous value of the integrated voltage (15), means for comparing this measure to a calibrating curve of the integrated voltage versus the angle.