REAL-TIME STRUCTURAL MEASUREMENT (RTSM) FOR CONTROL DEVICES

摘要

The present invention shows a solution to measure the relative displacements related to a structure in order to use the signal measured as feedback signal in real time for the structural monitor of the active and semi-active vibration. Said monitors reduce the structural movement caused by any source of natural or artificial vibration. The conventional measurement methods of the relative displacement are often not able to accurately measure the displacement in real time. The delay in the signal measured often has a negative effect on the feedback monitor device.;The invention consists in a pre-stressed axial element (1), installed between two different points of the structure (2) using a fixed connector (5) and a flexible one (6). As the structure (2) vibrates in response to an external “source”, a relative displacement is caused between two connecting points of the axial element, which can be measured based on the rotation φ of the flexible connector (5) of the axial element. In addition, at intermediate points of the axial element (1), the relative displacement between the structure (2) and the axial element (1) can be measured through sensors (3). With these measurements, the form of discrete displacement can be obtained in real time of the whole structure where the axial element (1) is installed.;In the event an axial element (4) is installed, where an upper mode passes through point zero, the modal displacement of this upper mode will not be measured. Assuming that the full displacement of the structure is associated with the first two modes, which is often a god approach in practice to earthquake-induced displacements, the modal displacement of these two modes can be measured independently in real time. A modal monitor through active or semi-active devices can improve the structural behavior in some cases.;In order to keep the disturbance level of the signal measured introduced by natural vibrations of the axial element (1) as low as possible, it is important that the fundamental frequencies of the axial elements (1) are significantly higher than the natural frequencies of the structure (2). For this goal to be achieved, using materials of the axial element is necessary, which have little density and can be highly pre-stressed, such as carbon fiber.

主权项

1. A system to measure in real-time dynamic displacements of structures relative to a reference, comprising:
one or more axial elements installed and pre-stressed between two connection points of a flexible structure having a base; and a rotation measuring sensor, as a laser sensor used to measure rotation between a reference of structure and the axial elements, wherein the reference corresponds to the undeformed structure and wherein the measuring sensor is placed at a fixed-to-the-base connection or alternatively at a fixed-to-the structure connection which forms the mentioned connection points of the axial elements to the structure, to obtain the relative displacement between the reference and the pre-stressed axial element, measured in perpendicular direction to the axial element, and obtained by multiplying the length of the axial element by the tangent function of the measured rotation φ between reference and the axial elements. wherein the relative displacement obtained can be used in controlling structural vibrations due to natural causes such as earthquakes, wind, sea waves, or human generated actions through machines, people movement, vehicles, explosions, or other sources.