Abstract:
The present invention relates to high sensitivity elastic deflection sensors, more particularly related to capacitively coupled FET based elastic deflection sensors. A sub-threshold elastic deflection FET sensor for sensing pressure/force comprises an elastic member forming a moving gate of the sensor, fixed dielectric on substrate of the FET, and a fluid dielectric between the elastic member and the fixed dielectric, wherein alteration in the height of the fluid dielectric (TSENS) due to pressure/force on the elastic member varies the sensor gate capacitance.
Abstract:
The present invention is directed toward devices comprising carbon nanotubes that are capable of detecting displacement, impact, stress, and/or strain in materials, methods of making such devices, methods for sensing/detecting/monitoring displacement, impact, stress, and/or strain via carbon nanotubes, and various applications for such methods and devices. The devices and methods of the present invention all rely on mechanically-induced electronic perturbations within the carbon nanotubes to detect and quantify such stress/strain. Such detection and quantification can rely on techniques which include, but are not limited to, electrical conductivity/conductance and/or resistivity/resistance detection/measurements, thermal conductivity detection/measurements, electroluminescence detection/measurements, photoluminescence detection/measurements, and combinations thereof. All such techniques rely on an understanding of how such properties change in response to mechanical stress and/or strain.
Abstract:
PURPOSE:To reduce an error of measurement with a stress measuring device, by providing a plus/minus sensitivity correcting circuit to correct the level of the detection signal of a reception processing circuit and setting both tensile stress and compression stress at the same level. CONSTITUTION:An energizing circuit of energizing coils 31 and 32 of detection terminals consists of an oscillator 17 and a coil driver 18 and is energized by a 1kHz alternating current. A reception processing circuit which processes the induced voltage of detection coils 41 and 42 consists of a photocoupler 19, a diode driver 20, a phase controller 30, a comparator 31 and an integration circuit 32. An operator selects a set corresponding to the material of a measurement subject among sets 351-356 and sets a selector switch 34 to control a variable resistance VR of the controller 30 so as to obtain the maximum absolute value for display of a voltmeter MET. Then the foot tips of cores 1 and 2 are made touch onto the measuring point of the measurement subject, and the detection terminal is turned round the center shaft of the detection terminal. The display is read when the value of the meter MET shows the maximum and minimum values. The revolving angle obtained at that time point is read as the direction of the main stress.
Abstract:
PURPOSE:To unnecessitate a signal amplifier and a signal converter, by overlapping a plurality of pressurizing conductors on both surfaces of which electrodes are provided, and differentiating the conductive characteristics of the pressurizing conductors in correspondence with the magnitude of a force that is applied to the direction of the overlapped thickness. CONSTITUTION:A contactor (not shown in the Figure) is constituted by a pushing piece 2a and a compressing plate 2b. Five electrodes (41a and 41b), (42a, and 42b and 42c), (43a, and 43b and 43c), (44a, and 44b and 44c), and (45a and 45b) are formed by insulators 41a-45a and conductors 41b-45b. The areas of said five electrodes are gradually made small. When a force F is applied to the pushing piece 2a in the direction of an arrow, the force F is applied to the electrodes (41a and 41b) through the compressing plate 2b. The pressure per unit area applied to pressurizing conductors 3a-3d is determined by the areas of five electrodes, respectively. The pressurizing force F can be formed by said pressure, i.e. conductive or nonconductive state of the pressurizing conductors.
Abstract:
A pressure testing device for calculating a pressure in a flexible line comprises a housing unit, a force sensor mounted on the housing unit and a clamp assembly having a clamp mounted on the housing unit. The clamp is operable to compress the flexible line against the force sensor by a predetermined degree of deformation of the flexible line. The device includes a displacement sensor adapted to measure a displacement of the clamp. The device also includes a controller having a processor in communication with the force sensor and the displacement sensor, and a memory unit containing stored data. At the predetermined degree of deformation of the flexible line, the processor compares a first signal from the force sensor and a second signal from the displacement senor with the stored data to estimate the pressure within the flexible line.