Abstract:
The present invention refers to a method for the determination of the physical features of a tire, for example the deformations that it undergoes during the use. The method for the determination of the physical features of a tire, comprises at least a first belt (3,4) reinforced with a plurality of metallic wires, characterized by comprising the following phases: providing a signal between a first and a second metallic wire; determining the real part and the imaginary part of the impedance between said first metallic wire and said second metallic wire.
Abstract:
A device for detecting the pressure exerted at different points of a flexible and/or pliable object that may assume different shapes, comprises a plurality of capacitive pressure sensors and at least a system for biasing and reading the capacitance of the sensors. The requirements of flexibility or pliability are satisfied by capacitive pressure sensors constituted by two orthogonal sets of parallel or substantially parallel electrodes spaced, at least at each crossing between an electrode of one set and an electrode of the other set, by an elastically compressible dieletric, constituting an array of pressure sensing pixel capacitors. Further described is a method of trimming a sail for maximizing the net thrust on the windward face of the sail based on instrumentally reconstructing distribution maps of the pressure over the sail area in real time and with a certain frame rate.
Abstract:
A method for reading a capacitive sensor ( Fig. 1 ), constituted by an array of capacitors (C PIX_JK ) ordered in rows and columns functionally connected through row lines (R J ), each one electrically constituting a first plate in common to all the capacitors of a row, and through column lines (C K ), each one electrically constituting a second plate in common to all the capacitors of a column, the two sets of plates being orthogonal or quasi-orthogonal to each other, is provided. The method may be implemented by a circuit for biasing and reading capacitances that includes circuits for selecting a column line and a row line, a charge amplifier producing an output voltage representing the capacitance of the selected capacitor intercepted by the selected column and row lines, and comprises the steps of preliminarily resetting the output voltage of the charge amplifier, connecting to a reference voltage all the deselected row and column plates of the array and connecting an auxiliary capacitor and the selected capacitor to an inverting input of the amplifier and as feedback capacitor of said amplifier, respectively, or viceversa, applying a step voltage on the capacitor that is connected to the inverting input of the amplifier and reading at steady-state, the output voltage. An integrated reading system ( Fig. 2 ) for a capacitive sensor is also provided.
Abstract:
A plurality N of capacitance sensing cells are arranged in a row/column array top to cooperate with a fingertip and produce an output signal that controls the movement of a cursor/pointer across a display screen. The output of each individual sensing cell is connected to the corresponding individual node of a resistor array that has N nodes arranged in a similar row/column array. A centroid output of the resistor nodes in row configuration provides an output signal for control of cursor movement in a row direction. A centroid output of the resistor nodes in column configuration provides an output signal for control of cursor movement in an orthogonal column direction. A mass signal output of the row/column resistor mode array provides a switch on/off signal.
Abstract:
A distance sensor has a capacitive element in turn having a first capacitor plate which is positioned facing a second capacitor plate whose distance is to be measured. In the case of fingerprinting, the second capacitor plate is defined directly by the skin surface of the finger being printed. The sensor comprises an inverting amplifier, between the input and output of which the capacitive element is connected to form a negative feedback branch. By supplying an electric charge step to the input of the inverting amplifier, a voltage step directly proportional to the distance being measured is obtained at the output.