Abstract:
Apparatus (2) for sensing and measuring and/or shear components of a force at an interface between two surfaces, which apparatus (2) comprises: (i) at least one flexible means (4) for receiving the pressure and/or shear components of the force; and (ii) transducer means (6) for producing electrical signals consequent upon movement of the flexible means (4) in response to the pressure and/or shear components of the force, and the apparatus (2) being such that: (iii) the flexible means (4) comprises first and second electrode parts (18, 20) which are spaced apart by the flexible means (12); (iv) the first and second electrode parts (18, 20) move solely towards each other as a result of the pressure component of the force being applied to the flexible means (4); and (v) the first and second electrode parts (18, 20) move towards and parallel to each other as a result of the shear component of the force being applied to the flexible means (4).
Abstract:
A method of constructing a sensor includes depositing a first material in a predetermined arrangement to form a structure. The depositing results in at least one void occurring within the structure. The method further includes depositing a second material within the voids. The second material may have electrical properties that vary according to deformation of the second material. The method also includes providing electrical access to the second material to enable observation of the one or more electrical properties. A sensor includes a structure that has one or more voids distributed within the structure. The sensor also includes a material deposited within the one or more voids. The material may be characterized by one or more electrical properties such as piezoresistivity. The sensor includes a first contact electrically coupled to a first location on the material, and a second contact electrically coupled to a second location on the material.
Abstract:
A method of measuring biaxial stress in an object of a ferromagnetic material in which material in a region (10) in the vicinity of a surface of the object is subjected to a conditioning method by application of a conditioning magnetic field that is at least initially at a high field strength. Values of biaxial stress within the said region are measured with an electromagnetic measuring probe (14) in at least two different orientations, the electromagnetic measuring probe (14) using an alternating measuring magnetic field that is at a field strength well below saturation. The conditioning may subject the region (10) to a low frequency alternating magnetic field (38, 58) initially at a high field strength, and gradually reducing the strength to zero over a decay time period at least equal to the time for many cycles of the low frequency magnetic field. Conditioning the material enables the stress to then be measured more accurately, and enables ambiguities in biaxial stress to be resolved.
Abstract:
Exemplary systems and method are directed to a sensing device, and to a pressure sensing system and method. An exemplary method includes supplying electromagnetic energy to a transducer which is configured to reflect the electromagnetic energy at a ring frequency determined by an inductance of the transducer, wherein the inductance changes in response to compression of the inductive element. The ring frequency of electromagnetic energy reflected by the transducer is correlated to a pressure value.
Abstract:
A device (1) for measuring mechanical forces comprising a sensor (3) adapted to measure difference of stresses in two orthogonal measuring directions (5a-b). The device comprises at least one force receiving element (2a-b) adapted to receive the forces to be measured, and the sensor is adapted to measure the forces applied to the force receiving element. The device further comprises a transducer (4) of a tubular shape, adapted to transfer the forces from the force receiving element to the s e n s o r and to convert the forces received by the receiving element into forces suitable for the sensor, the force receiving element (2a-b) comprises a flange extending outward in a radial direction from the transducer (4), and the force receiving element (2a-b) and the sensor (3) are mounted at a distance (l) from each other along the longitudinal axis of the transducer.
Abstract:
A mechanical amplifier includes first and second amplifier mounting pads (110,120) and first and second sensor mounting pads (130, 140). At least one of the first and second amplifier mounting pads (110,12o) receives a load or displacement. The first and second sensor mounting pads (130, 140) connect to the first and second amplifier mounting pads (130, 140) via flexible connecting members. A sensor (150) may connect to the first and second sensor mounting pads to measure the amount of load or displacement.
Abstract:
The invention provides a pressure transducer comprising: a closed container (5) having a pair of opposed interior walls (6 and 7) between which is disposed a magnetostrictive element (1); means (9 and 10) to create a magnetic field within the element so as to energise it; and means (11) to detect the resonant frequency of the element, thereby to produce an output indicative of the pressure exerted on the transducer.
Abstract:
A magnetostrictive sensor structure, the coils of which can be easily wound by a robot without manual operations to reduce its production cost and improve product quality as well as measurement accuracy. Two imaginary lines (M) are drawn in directions at 45 DEG to the right and left with respect to the horizontal and vertical axes of a rectangular thin plate (52) made of a ferromagnetic material such as a permalloy, in such a manner that they pass the center of the plate. The four sides of the rectangular plate (52) are provided with cuts (53 and 54) within the respective sections defined by the two imaginary lines (M), and coils are wound on the paired bottoms (57) of the opposite cuts (53 and 54), so that an excitation coil (34) and an output coil (36) are formed.
Abstract:
A non-contact, current sensor includes a gapped magnetic core configured to circumscribe a current carrying conductor. A magnetostrictive element is mechanically coupled to the gapped magnetic core. Current flowing in the current carrying conductor induces a magnetic field in the magnetic core that flows through the magnetostrictive element. The gapped magnetic core is provided with mounting sections to which the magnetostrictive element is mechanically coupled. The mounting sections have a geometry that increases magnetic flux in the magnetostrictive element. A strain gauge is mechanically coupled to the magnetostrictive element to measure displacement in the element induced by the magnetic flux.
Abstract:
The invention relates to a transport rail system (1) capable of detecting a weight of a rail vehicle (2). The transport rail system (1) comprises one or more rails (3a, 3b) and one or more sensors (7) for measuring a magnetic property. At least one of the sensors (7) is adapted to measure a change of a magnetic property in order to determine a weight bearing on one or more of the rails (3a, 3b), the change of the magnetic property being caused by stress exerted on the rail (3a, 3b) by said weight. Said transport rail system (1) is characterized in that one or more of the sensors (7) are adapted to measure the change of a magnetic property of the rail (3a, 3b) itself and/or that one or more sensors (7) are adapted to measure the change of a magnetic property of a supporting structure (4a, 4b) of the rail (3a, 3b). The invention allows providing a transport rail system (1) at a lower price as the complexity of such a system may be lowered.