Abstract: A system and methods for weak spot analysis. A mesh shape is preprocessed to approximate an input model for an object. The mesh shape is analyzed with modal analysis to identify weak regions. A method and system for determining weak spots in an object. The method and system uses an optimization problem which is solved to determine a pressure distribution on the object maximizing maximal principal stress by solving a set of optimization problems maximizing stress for each point of the object.

Abstract: Methods for monitoring components are provided. A component has an exterior surface. A method includes locating a centroid of a reference feature configured on the component, and measuring a first value of a characteristic of the reference feature relative to the centroid at a first time. The method further includes measuring a second value of the characteristic relative to the centroid at a second time after the first time, and comparing the first value and the second value.

Abstract: A method of fabricating a mechanical part of structure that is defined relative to a predictive search of the risks of crack initiation therein by using a method of calculation by finite elements. A coarse mesh (9) is taken into account, and the individual size of the meshes (20) and a critical distance (d) are defined jointly by an operator. The meshes (20) making up the mesh (9) are defined to be of identical mesh size, with the critical distance (d) being defined as the sum of an integer number of depth dimensions of said meshes (20). If the results of the calculation by finite elements diverge, then a calibration weighting function is advantageously applied that takes account of the size of the meshes (20) by taking account of the critical distance (d).

Abstract: A monitoring device for a repair patch that can be placed on or in a wall of an aircraft to repair a defect has a sensor device for detecting properties of the repair patch placed in the wall, an energy supply device for supplying energy at least to the sensor device, and a communication device so as to read out the sensor data. A repair kit that can be placed in or on a wall of an aircraft to repair defects comprises a repair patch for repairing a defect in or on a wall of an aircraft and also comprises a monitoring device. A method for monitoring a repair patch in or on a wall of an aircraft by means of a monitoring device comprises the steps of detecting a measurement phase on the basis of the amount of energy provided by the energy supply device, measuring load parameters in and/or on the repair patch during the measurement phase, and reading out the load parameters.

Abstract: A wheel testing system and method are provided that simulates realistically conditions likely to be encountered during operation of vehicle wheels, especially powered drive wheels and wheel-connected structures. The system may include an integral support frame designed to adjustably mount wheels or wheel-connected structures to be tested, a load motor drivingly connected to an inertial load, and an adjustable mounting sled configured to adjustably mount a test wheel or a wheel-connected structure with an hydraulic system actuatable to adjust the location of the test wheel relative to the inertial load to vary or fix the load on the test wheel desired. Speed of the test wheel can be varied or fixed by controlling the speed of the load motor. System measurement and data collection electronics measure a range of selected wheel parameters and gather data for transmission to a processor or non-transitory storage medium for processing and evaluation.

Abstract: A flight control system loading test apparatus includes a surface-mounted sector, a cam profile sector, a dummy weight, and a cable. The surface-mounted sector attaches to an aircraft flight control system body such that the surface-mounted sector pivots along with the body about a pivot axis. The cam profile sector is configured to rotate about a rotational axis among a plurality of loading positions. The cam profile sector includes a profile surface having a plurality of curves. Each curve follows a different radius emanating from a respective axis substantially parallel to the rotational axis of the cam profile sector. The cable contacts the cam profile sector along the profile surface. An applied hinge moment using the dummy weight varies as the cam profile sector rotates about the rotational axis.

Abstract: An overload detecting assembly comprising a lateral probe (18) which cooperates with a first load bearing member (10) as it moves towards a second load bearing member (11) and in turn deflects an indicator member (20) which may take a permanent set when a yield point is exceeded. Ready inspection of the indicator member reveals whether or not it has been bent. The indicator member may comprise a cantilevered beam (24) formed in a sleeve (20) coaxial with the load bearing members (10, 11). Alternatively, an extension (25) of the probe (18) may deflect laterally at a midpoint under overload conditions. Alternatively, the probe (18) may form an impression in an indicator member (30) under overload conditions.

Abstract: A diamond-shaped actuator for a flexible panel has an inter-digitated electrode (IDE) and a piezoelectric wafer portion positioned therebetween. The IDE and/or the wafer portion are diamond-shaped. Point sensors are positioned with respect to the actuator and measure vibration. The actuator generates and transmits a cancelling force to the panel in response to an output signal from a controller, which is calculated using a signal describing the vibration. A method for controlling vibration in a flexible panel includes connecting a diamond-shaped actuator to the flexible panel, and then connecting a point sensor to each actuator. Vibration is measured via the point sensor. The controller calculates a proportional output voltage signal from the measured vibration, and transmits the output signal to the actuator to substantially cancel the vibration in proximity to each actuator.

Abstract: A load cell extending in an axial direction having an outer surface includes a groove in the outer surface having a first flat wall, and a second flat wall; and a principal strain sensor positioned on the first flat wall to measure tension and compression in the axial direction.

Abstract: A method for estimating a loading criterion relating to the load experienced by a structural component of an aircraft, and assistance with detecting a so-called “hard” landing. The method includes measuring parameters of the aircraft and calculating at least one loading criterion for the loading of the structural component using at least one neural network receiving the parameters as input. Assistance with detecting a hard landing then includes determining of a time of impact of the aircraft on a landing strip from the measured parameters, then estimating a plurality of the parameters at the determined time of impact so as to calculate the at least one loading criterion relating to the loading of the structural component.

Abstract: A device for acquiring mechanical loads on mechanically loaded bodies is provided. The device exhibits a resonance-capable micro-bridge structure, an alternating voltage source with a variable frequency, an impedance measuring device for acquiring the impedance of the micro-bridge structure and an electronic unit for receiving determined impedance values and changing the frequency of the alternating voltage source. By exciting the micro-bridge structure and measuring its impedance, a conclusion can be drawn as to the expansion-dependent resonance frequency, which in return makes it possible to determine the expansion, and hence the mechanical load. Such a device is sufficiently accurate, and largely independent of outside influences.

Abstract: An overload detecting assembly comprises a first load bearing member (10) adapted to flex laterally in response to a load to be monitored, a second load bearing member (11) spaced from the first under normal load conditions and which is contacted and loaded by the first load bearing member (10) when it is loaded beyond a load limit. Preferably, the first load bearing member (10) has a yield point below the load limit and takes a permanent set once the yield point has been exceeded. A lateral probe (18) cooperates with the first load bearing member as it moves towards the second load bearing member and in turn deflects an indicator member (20) which takes a permanent set when a yield point is exceeded. Ready inspection of the indicator member then reveals whether or not it has been bent.

Abstract: The invention pertains to a planking panel (B) for a structural component (1) that is realized in the form of a sandwich component in its inner region (BI) that extends in a planar fashion and features a first skin section (11), a second skin section (12) and a core section (13) that is situated between these two skin sections, wherein the core section (13) connects the first and the second skin sections (11, 12) to one another in a planar fashion, with the invention being characterized in that a plurality of monitoring lines (14) is provided that extend over a planar section of the core section (13) to be monitored in order to detect damage in the core section (13) and respectively feature a first connection point (15) on a first end (14a) and a second connection point (16) on a second end (16a) in order to apply a monitoring signal (UK), wherein the monitoring lines (14) have a tear strength that lies in the range between 50% and 100% of the tear strength of the core section (13).

Abstract: Methods, devices, and systems relating to a sensing device are disclosed. A device may comprise a structure including a first surface and a second, opposite surface, wherein the structure comprises one or more segments. Further, the device may include a plurality of sensors disposed on the structure, wherein each segment of the one or more segments comprises a first sensor of the plurality of sensors coupled to the first surface and an associated second sensor of the plurality of sensors coupled to the second surface. Moreover, each sensor of the plurality of sensors may be configured to measure a strain exhibited on an adjacent surface of the structure at an associated segment of the one or more segments.

Abstract: A strain measurement device to assess the integrity of a structural repair to a surface comprises a detector, a processor, and a memory module coupled to the processor. The memory module comprises logic instructions stored in a computer readable medium which, when executed by the processor, configure the processor to use the detector to obtain a first strain measurement from an external strain indicator, use the detector to obtain a second strain measurement from the measurement sensor after at least one stress test is applied to the structural repair, and generate a signal when a difference between the first strain measurement and the second strain measurement exceeds a threshold.

Abstract: A method and an arrangement to determine an incidence of loading of an aircraft structure. A true reality of at least one aircraft structural section is superposed with the virtual reality of the aircraft structural section, and any deviation is established by means of a comparison of the two realities; this deviation is evaluated with reference to its consequences in terms of the structural mechanics involved.

Abstract: A monitoring device for a repair patch that can be placed on or in a wall of an aircraft to repair a defect has a sensor device for detecting properties of the repair patch placed in the wall, an energy supply device for supplying energy at least to the sensor device, and a communication device so as to read out the sensor data. A repair kit that can be placed in or on a wall of an aircraft to repair defects comprises a repair patch for repairing a defect in or on a wall of an aircraft and also comprises a monitoring device. A method for monitoring a repair patch in or on a wall of an aircraft by means of a monitoring device comprises the steps of detecting a measurement phase on the basis of the amount of energy provided by the energy supply device, measuring load parameters in and/or on the repair patch during the measurement phase, and reading out the load parameters.

Abstract: Gripping claws and pairs of arched angular profiles are arranged along the perimeter of a cylindrical surface segment so as to grip the edges of a fuselage panel, closing the opening of a pressurizable chamber.

Abstract: A method for steadying an aircraft using jack props, in which: a number and location of the props to be used is determined as a function of an area of operation, on the basis of a prop map; strain gauges arranged on the structure of the aircraft are used; predetermined props that are to be used are fitted; the strains measured by at least one strain gauge situated in the operating zone are checked; and the load applied by at least one prop positioned in the operating zone is regulated according to the strains measured by the gauge and so as to minimize the strains. A steadying device can implement the method.

Abstract: A process for testing the quality, in particular the stiffness and the phase, of an elastic joint for connecting two other parts while filtering vibrations transmitted between these two other parts, said elastic joint being meant to work in axial, radial or torsional direction, disposing or not disposing of one or more hydro-elastic chambers and of two cylindrical concentric support elements, the inner support element being located to a large extend inside the volume defined by the outer support element, the two support elements being connected by a set of components made of rubber or elastomer or, if applicable, of plastic and metallic parts, wherein said support elements are themselves respectively attached to the two other parts which the elastic joint connects, wherein a technique of testing by impact is applied within the timing of the production line of the elastic joint, i.e.

Abstract: A testing device for structural panels is characterized in that it includes passive apparatus in the form of a mount and interface apparatus between the mount and the panel to geometrically apply stresses representing the stresses caused by the parts surrounding the panel during a normal utilisation thereof.

Abstract: Pin bearing arrangement (10) for measuring loads in an aircraft landing gear (1), comprising a trailing arm (2), connected to at least one of the aircraft wheels (3), and a shock absorber (4), connected to the aircraft, whereby load (11) is transferred from the trailing arm (2) to the shock absorber (4), the trailing arm (2) being rotatable with respect to the shock absorber (4), the pin bearing arrangement (10) comprising at least one strain measuring element (12) attached to the pin bearing arrangement (10) in predetermined positions, these positions being selected such that the strain measuring element (12) gives at least a minimum detectable signal when the load (11) transferred is over a first threshold value, for any value of the angle (5) adopted by the trailing arm (2) with respect to the shock absorber (4).

Abstract: A reinforced panel (1) comprising: a composite skin (2); a plurality of stringers (3, 4) bonded to the skin; and one or more strain actuators (5), each positioned between an adjacent pair of stringers. A load is applied to the panel in the plane of the skin, and a local strain is applied to the skin by the strain actuators when the compressive load exceeds a predetermined threshold. This causes the skin to buckle and reduce interface stresses between the skin and the stringers.

Abstract: The method and apparatus for tracking a center of gravity (COG) of an air vehicle provides a precise calculation and updating of the COG by disposing a plurality of acceleration measuring devices on a circumference of one or more rings in a manner that establishes redundancy in acceleration measurement. A multivariable time-space adaptive technique is provided within a high speed digital signal processor (DSP) to calculate and update the position of the COG. The system provides the capability of executing a procedure that reduces dispersion in estimating angular velocities and lateral accelerations of a moving vehicle and corrects the vehicle's estimated angular velocities and lateral accelerations. In addition, a consistency check of the measured values from the acceleration measuring devices is performed to assist in fault detection and isolation of a faulty accelerometer in the system.

Abstract: A method for producing a missile nose cone is disclosed. The method consists of manufacturing a first missile nose cone from a first lot of polymeric material and determining a first rupture value. The method further consists of manufacturing a second missile nose cone from a second lot of polymeric material and determining a second rupture value of the second missile nose cone. Both first and second lots of material are mixed into a test batch with one another based on their associated rupture values. An evaluation missile nose cone is then manufactured from the test batch and a determination is made as to whether the evaluation missile nose cone has a desired rupture value. If a desired rupture value is not obtained, then the mixing and evaluation steps are repeated.

Abstract: Pin bearing arrangement (10) for measuring loads in an aircraft landing gear (1), comprising a trailing arm (2), connected to at least one of the aircraft wheels (3), and a shock absorber (4), connected to the aircraft, whereby load (11) is transferred from the trailing arm (2) to the shock absorber (4), the trailing arm (2) being rotatable with respect to the shock absorber (4), the pin bearing arrangement (10) comprising at least one strain measuring element (12) attached to the pin bearing arrangement (10) in predetermined positions, these positions being selected such that the strain measuring element (12) gives at least a minimum detectable signal when the load (11) transferred is over a first threshold value, for any value of the angle (5) adopted by the trailing arm (2) with respect to the shock absorber (4).

Abstract: Systems and methods for determining center of gravity for an aircraft. An example system includes one or more load measurement devices that generate one of nose gear or main gear weight information and a processing device that determines center of gravity of the aircraft based on previously received gross weight information and the generated nose or main gear weight information. The number of gear sets with load measurement devices is one less that the total number of gear sets having distinct longitudinal positions along a fuselage of the aircraft. The processing device further determines center of gravity based on temperature and/or pitch attitude information. The system includes a user interface that allows a user to enter the gross weight information that might be included in a flight manifest or a load and trim sheet and/or a communication component that receives the gross weight information from a ground-based system.

Abstract: The device includes two supports and a primary conductive strip. The primary conductive strip includes a neutral surface, a first side, and a second side. The primary conductive strip is connected one of directly and indirectly on the first side to the two supports such that the primary conductive strip is constrained in two dimensions and movable in one dimension. The device also includes a primary distributed feedback fiber laser. The primary distributed feedback fiber laser includes a fiber axis. The primary distributed feedback fiber laser is connected to the primary conductive strip along one of the first side and the second side such that there is a positive distance between the neutral surface of the primary conductive strip and the fiber axis of the primary distributed feedback fiber laser.

Abstract: A method and system for determining the reliability of a rotating component compares a normalized stress curve with a normalized strength curve. The resulting overlap corresponds with the reliability of the rotating component.

Abstract: Structural health monitoring apparatuses and methods are disclosed. One or more structural health sensors may be used to disconnect and/or connect one or more RFID chips to an antenna such that wireless communication with the one or more RFID chips (or the absence of wireless communication) through the antenna indicates the structural health status. Example structural health sensors may be moisture detecting or fracture detecting. A remote reader may be used to establish the wireless communication with the one or more RFID chips to determine the structural health. The sensors and RFID chips may be passive and powered through the wireless communication from the remote reader. Such apparatuses and methods may be applied to any large structures requiring regular inspection, such as aircraft, ships, automobiles or buildings.

Abstract: The present invention provides a device for test loading a fuselage barrel, in particular in the aviation and aerospace industry. The device comprises a first and a second pressure bulkhead for sealing the fuselage barrel at the end faces thereof in a pressure-tight manner. The device further comprises a support device which may be coupled to the first pressure bulkhead, on the one hand, and to the second pressure bulkhead, on the other hand, extending through the fuselage barrel. Moreover, the device comprises a loading device which may be coupled to the support device, on the one hand, and to a portion of the fuselage barrel, on the other hand, for introducing loads into the fuselage barrel.

Abstract: A structural health monitoring arrangement includes a component formed of fibre reinforced composite material with a plurality of electrical conducting fibres intrinsic to the composite defining electrical paths that run through the composite. The paths act as sensing paths running through the material and a detector watches for changes in electrical property indicative of a structural event. The paths may be configured as an open or a closed node grid whose electrical continuity is monitored directly or indirectly. Alternatively they may be fibres having a piezoresistive property and the changes in resistance may be monitored.

Abstract: The invention concerns a method of dimensioning and producing stiffened structural components (4) comprising at least one shell component (6) and at least one stiffening component (8) which can be connected thereto, in which the shell component (6) and the at least one stiffening component (8) is dimensioned on the assumption of intactness of the at least one stiffening component and having regard to a predetermined safety factor and/or a predetermined structural inspection interval in which a predetermined maximum crack progression in the shell component is not to be exceeded and/or the strength of the structural component is not to fall below a predetermined minimum residual strength, and in which the at least one stiffening element (8) of the structural component dimensioned by this method is equipped with at least one structural condition sensor (30) for detecting intactness; as well as the use of structural condition sensors in an aircraft, in particular a passenger aircraft.

Abstract: A transducer for use with a boundary-stiffened panel has an inter-digitated electrode (IDE) and a piezoelectric wafer portion positioned therebetween. The IDE and/or the wafer portion are triangular, with one edge or side aligned with a boundary edge of the panel. The transducer generates and transmits an output force to the panel in response to an input voltage signal from a sensor, which can be another transducer as described above or an accelerometer. A controller can generate an output force signal in response to the input voltage signal to help cancel the input voltage signal. A method of using the transducer minimizes vibration in the panel by connecting multiple transducers around a perimeter thereof. Motion is measured at different portions of the panel, and a voltage signal determined from the motion is transmitted to the transducers to generate an output force at least partially cancelling or damping the motion.

Abstract: A method and system for determining the reliability of a rotating component compares a normalized stress curve with a normalized strength curve. The resulting overlap corresponds with the reliability of the rotating component.

Abstract: A method of designing and manufacturing apparatus. The method comprises: creating a design space; analysing expected loads acting on the design space to calculate a first load path within the design space; analysing expected loads acting on the design space when the apparatus is in a damaged state to calculate a second load path within the design space; selecting a region of the second load path which falls outside the first load path; and creating a final design which includes: a primary structure falling within the first load path; and a damage indication feature falling within the selected region. The damage indication feature is designed to provide a visual indication when the load transmitted by the damage indication feature exceeds a threshold.

Abstract: A solution for monitoring a property of an object and/or an area using a Micro-ElectroMechanical Systems (MEMS)-based monitoring device is provided. In an embodiment of the invention, the MEMS-based monitoring device includes a MEMS-based sensing device for obtaining data based on a property of the object and/or area and a power generation device that generates power from an ambient condition of the monitoring device. In this manner, the monitoring device can operate independent of any outside power sources or other devices. Further, the monitoring device can include a transmitter that transmits a signal based on the property. The monitoring device can be used to monitor a moving component of a machine, and can be integrated with a health monitoring system of the machine using one or more relay devices.

Abstract: A deterministic non-destructive evaluation system for composite damage assessment and repair includes structure of interest, non-destructive evaluation data and strength test data obtained on the structure of interest, finite element analysis performed on a structural model modified by the non-destructive data and the strength test data, a strength-to-indication correlation based on the finite element analysis and deterministic non-destructive evaluation predictions and recommendations based on the strength-to-indication correlation.

Abstract: Apparatus for indicating loading in a structure having exceeded a predetermined threshold is disclosed in which deformation of a structural element is identified by the torque required to rotate a gauge assembly integrated in the structure.

Abstract: Gripping claws and pairs of arched angular profiles are arranged along the perimeter of a cylindrical surface segment so as to grip the edges of a fuselage panel, closing the opening of a pressurizable chamber.

Abstract: An integratable sensor for an airfoil of an aircraft such as an airplane and a helicopter comprises a sensor capsule, in whose inner chamber a measuring element for measuring an environmental parameter is situated. A capsule carrier is implemented to accommodate and removably attach the sensor capsule and is integratable in an airfoil of an airplane or a helicopter. Elastic contact elements are used for secure electrical connection of the sensor capsule to the capsule carrier. The sensor capsule is replaceable, while the capsule carrier is permanently integrated in the airfoil, in particular in a rotor blade. The measuring element is, for example, a pressure sensor.

Abstract: A reinforced panel (1) comprising: a composite skin (2); a plurality of stringers (3, 4) bonded to the skin; and one or more strain actuators (5), each positioned between an adjacent pair of stringers. A load is applied to the panel in the plane of the skin, and a local strain is applied to the skin by the strain actuators when the compressive load exceeds a predetermined threshold. This causes the skin to buckle and reduce interface stresses between the skin and the stringers.

Abstract: A flap simulator for an aircraft has a support with a handle. A first couple is on the support and is selectively engageable to a flap track for guiding an aircraft flap. A second couple is also on the support and is selectively engageable to a flap actuator for moving the aircraft flap along the flap track. The support may have an adjustment feature that allows a size of the second couple to be changed to accommodate the flap actuator. The support is apart from the aircraft flap.

Abstract: A device for detecting synchronous errors of high-lift surfaces such as landing flaps or slats on aircraft, having an optical conductor which is laid over at least two adjacent high-lift surfaces, a light source and an optical receiver which are allocated to different ends of the optical conductor, as well as an evaluation unit for determining a synchronous error of the high-lift surfaces on the basis of the light signal received from the optical receiver.

Abstract: A method of producing polymer/nanotube composites where the density and position of the nanotubes (11) within the composite ca be controlled. Carbon nanotubes (11) are grown from organometallic micropatterns. These periodic nanotube arrays are then incorporated into a polymer matrix (7) by deposing a curable polymer film on the as-grown tubes. This controlled method of producing free-standing nanotube/polymer composite films may be used to form nanosensor (3) which provide information regarding a physical condition of a material (20), such as an airplane chassis or wing, in contact with the nanosensor (3).

Abstract: The present invention provides a device for test loading a fuselage barrel, in particular in the aviation and aerospace industry. The device comprises a first and a second pressure bulkhead for sealing the fuselage barrel at the end faces thereof in a pressure-tight manner. The device further comprises a support device which may be coupled to the first pressure bulkhead, on the one hand, and to the second pressure bulkhead, on the other hand, extending through the fuselage barrel. Moreover, the device comprises a loading device which may be coupled to the support device, on the one hand, and to a portion of the fuselage barrel, on the other hand, for introducing loads into the fuselage barrel.

Abstract: In order to provide a turbine blade fatigue life evaluating method for quantitively evaluating the fatigue life of a turbine blade, the turbine blade is determined to be within its fatigue life if the creep elongation strain in the longitudinal direction of the turbine blade is less than 0.5% of an initial length, and is determined to exceed its fatigue life if the creep elongation strain is 0.5% or more than the initial length. A turbine blade creep elongation strain measuring apparatus 20 comprises a first fixed end 21, a second fixed end 22, and a dial gauge 24. A dimension in the longitudinal direction is stamped on the surface of a turbine blade.

Abstract: Apparatus for indicating loading in a structure having exceeded a predetermined threshold is disclosed in which deformation of a structural element is identified by the torque required to rotate a gauge assembly integrated in the structure.

Abstract: A method of detecting an event in a structure using a device having sensors and at least one actuator includes sending a signal from the at least one actuator encapsulated in the device, returning a reflected wave signal from the event to each of the sensors in the device, determining a respective duration of time for which the signal travels from the event to each of the sensors, and calculating a location of the event by using differences in the respective durations of time for which the signal travels from the event to each of the sensors to determine an angle and a distance at which the event is positioned.

Abstract: A test structure for dynamic seat tests comprises a load cell, a seat rail with a bar and a upper chord, a load transfer device, which comes into contact with opposite sides of the bar of the seat rail and is fixed to the load cell and an integrated floor plate which is fixed to the upper chord of the seat rail and to the load transfer device.