Abstract:
The airport monitoring system (1) for monitoring an airport territory (5), comprises an airport territory surface and an optic sensor system (70, 72a,...,72e, 100). The airport territory surface has a traffic infrastructure to support conveyance elements of a vehicle (90), e.g. an aircraft or a service vehicle, therewith allowing movements of the vehicle over the airport territory surface. The optic sensor system (70, 72a,...,72e, 100), includes an interrogator module (100) and fiber optic sensors (72a,...,72e) coupled thereto. The fiber optic sensors are arranged below the airport territory surface and have a respective plurality of optic strain-sensor elements (722) with mutually different optical characteristics. The interrogator module (100) transmits optical interrogation signals into the fiber optic sensors and receives respective response optical signals that have been modulated by the fiber optic sensors based on their optical characteristics. The interrogator module (100) identifies changes in the optical characteristics of the received respective response optical signals resulting from strains induced in the optic strain-sensor elements as a result of pressure exerted by a conveyance element (92) of a vehicle (90) on the airport territory surface (51) near a fiber optic sensor.
Abstract:
The embankment monitoring system comprises an optic sensor chain (10) and an interrogator (20). The optic sensor chain (10) comprises a series of intrinsic fiber optic sensors (12) that are mutually spaced with respect to each other in a longitudinal direction of the optic sensor chain and at least one optic fiber (14) to optically connect the plurality of intrinsic fiber optic sensors to the interrogator. The interrogator is configured to issue an optic interrogation signal and the intrinsic fiber optic sensors are configured to respond to the optic interrogation signal with an optic measurement signal that is indicative for at least one physical parameter (Pi) sensed by the intrinsic fiber optic sensors. The interrogator is further configured to process the optic measurement signals of the intrinsic fiber optic sensors to estimate a depth (d) as a function of a position (p) along said optic sensor chain (10).
Abstract:
A sensor system (10) and method for monitoring a powertrain (20) having a drive shaft (1). The sensor system (10) comprises an optical fibre (2) with a strain sensitive element (3). According to one aspect, a connection structure (4) is configured to hold at least a part of the optical fibre (2) with the strain sensitive element (3) at a radial distance (R2-R1) remote from the drive shaft (1) for amplifying the strain (S2) on the strain sensitive element (3) with respect to the strain (S1) on the drive shaft (1). According to a further aspect, at least three respective lengths of one or more optical fibres follow parallel, e.g. helical, paths with respect to each other to distinguish different strain forces.
Abstract:
Bridge based weigh-in-motion system A weigh-in-motion system for sensing dynamic strain variations in a bridge, comprising a plurality of strain sensors and a plurality of fixtures arranged as a plurality of sensing nodes; wherein each sensing node comprises: a first one of the fixtures comprising a first connector part and a first base attachable to a first location on the bridge; a second one of the fixtures comprising a second connector part and a second base attachable to a second location on the bridge; wherein the first location and the second location are separated by a distance B and define therebetween a measurement section; and one of the strain sensors that spans between and is fixed to the first and second connector parts by rigid fixings, separated by a distance A and defining therebetween a sensing section, so as to thereby form a spring connection between the first and second connector parts, the spring connection being extended or compressed to enable the strain sensor to provide an output signal dependent on the relative position of the first and second connector parts.
Abstract:
The sensor module (1) comprises an assembly of a carrier (20) of an elastic material and at least a first and a second longitudinal optic fiber section (11a, lib) with a first and a second fiber optic sensor element (12a, 12b). The first and a second longitudinal optic fiber section (11a, lib) are mounted to the carrier in a first and a second mutually different directions (x, y) at a respective pair of mutually opposite ends (13al, 13a2; 13b 1, 13b2). The sensor module is configured to receive a load action on a first load receiving side and to be restrained on at least a second side such as to enable a deformation of the carrier (20) by the load action in said a first and a second mutually different directions (x, y). The sensor module facilitates a temperature compensated measurement of the load action.
Abstract:
A system for ocean bottom sensing for performing geological survey. Herein the system comprising a cable further comprising a cable jacket (9), at least one optical fiber (6), and a plurality of detectors enclosed by the cable jacket (9). The latter including at least a first and a second detector (1, 2), the at least first and second detector (1, 2) comprising at least one intrinsic fiber optic sensor (3x, 3y, 3z, 3h, 3g, 3t). The detectors are communicatively connected to the at least one optical fiber (6) for allowing interrogation of the intrinsic fiber optic sensors (3x, 3y, 3z, 3h, 3g, 3t) and the cable jacket (9) has substantially a same cross-sectional diameter (D) and same outer shape at the at least first and second detector (1,2) and in between said first and second detector (1,2).
Abstract:
The invention is directed at an optical sensor device, comprising a sensing element for receiving an input action, an optical fiber comprising an intrinsic fiber optic sensor, and a transmission structure arranged for exerting a sensing action on the optical fiber in response to the input action, wherein the optical fiber is connected to a reference body and to the transmission structure with first and second connecting parts, the first and second connecting parts being located on either side of the intrinsic fiber optic sensor, wherein the transmission structure comprises a bi-stable spring having a first and a second stable deflection position and inbetween a negative stiffness range around an unstable equilibrium position, and wherein the optical fiber is pre-stressed thereby acting as a spring having a first spring constant of positive value to counteract a spring action of the bi-stable spring.
Abstract:
A deformable frame (10) for a fiber optic accelerometer (100). The frame (10) is formed by an interconnected stack of modular plates (10m, 10t). Attachment sections (13, 14, 15) are provided for attachment to an external structure (20) whose acceleration (A) is to be measured. At least one inertial section (16) is configured to allow a relative inertial motion (M) of the frame's inertial mass with respect to the one or more accelerated attachment sections (13, 14, 15). Transmission arms (11, 12) are pivotably attached to respective bridge sections (17,18) between the inertial section (16) an attachment section (15) such that the relative inertial motion (M) of the inertial mass in a sensing direction (Y) causes a transverse motion (S) in each of the transmission arms (11, 12) for stretching and/or compressing an optical fiber (1) with an optical strain sensor (2) attached between respective fiber attachment points (11a, 12a) on said transmission arms (11,12).
Abstract:
The airport monitoring system (1) for monitoring an airport territory (5), comprises an airport territory surface and an optic sensor system (70, 72a,...,72e, 100). The airport territory surface has a traffic infrastructure to support conveyance elements of a vehicle (90), e.g. an aircraft or a service vehicle, therewith allowing movements of the vehicle over the airport territory surface. The optic sensor system (70, 72a,...,72e, 100), includes an interrogator module (100) and fiber optic sensors (72a,...,72e) coupled thereto. The fiber optic sensors are arranged below the airport territory surface and have a respective plurality of optic strain-sensor elements (722) with mutually different optical characteristics. The interrogator module (100) transmits optical interrogation signals into the fiber optic sensors and receives respective response optical signals that have been modulated by the fiber optic sensors based on their optical characteristics. The interrogator module (100) identifies changes in the optical characteristics of the received respective response optical signals resulting from strains induced in the optic strain-sensor elements as a result of pressure exerted by a conveyance element (92) of a vehicle (90) on the airport territory surface (51) near a fiber optic sensor.
Abstract:
The invention relates to an optical sensor device comprising a reference body and at least one sensing transducer. The sensing transducer is arranged for moving relative to the reference body in response to an input action. The device further comprises an optical fiber and one or more transmission arms. The optical fiber comprises an intrinsic fiber optic sensor and is connected with a first connecting part to a first transmission arm and with a second connecting part to an element exterior to the first transmission arm. The first and second connecting parts are on either side of the intrinsic fiber optic sensor. A base of the first transmission arm is connected at a first part with the reference body and with a second part with the sensing transducer. The optical fiber is connected at a location along the first transmission arm remote from the base.