Abstract: A method for preparing a fully soft self-powered vibration sensor mainly uses a laser carbonization technology to prepare a two-dimensional porous carbon electrode with an origami structure, and then transfers the two-dimensional porous carbon electrode to a three-dimensional polydimethylsiloxane (PDMS) cavity through mold transfer; finally, a laser engraving technology is used to create microstructures on surfaces of the porous carbon electrode and a PDMS film. The sensor includes the PDMS film, a liquid metal droplet oscillator, a porous out-of-plane carbon electrode, and a 3D PDMS cavity assembled tightly from top to bottom.

Abstract: A personal communication device for processing financial information via a payment terminal, the payment terminal being configured to output a wireless signal is configured to receive the wireless signal of a payment terminal; determine whether the received wireless signal has a strength above a first signal threshold. If the received signal strength is above the first signal strength threshold, it emits a wireless request signal to cause the payment terminal to establish a communication channel with the personal communication device, wherein the request signal causes the payment terminal to establish only one communication channel, wherein the communication channel is only between the said personal communication device and the payment terminal.

Abstract: A method and system may track liquid consumption by a user from a liquid container using a flexible, network-connected, smart band. The smart band may detect orientations of the liquid container and identify sips taken by a user based on a pattern in the detected orientations. The smart band may also estimate a liquid consumption metric based on characteristics of the identified sips such as the duration of the sip. The identified sip as well as sip characteristics and the liquid consumption metric may be displayed on the smart band, and also may be transmitted to a server for storage and for display on another network-enabled device.

Abstract: A flexible electronic device includes a flexible electronic circuit and a flexible microfluidic sensor homogeneously integrated into the flexible circuit. The flexible sensor includes a flexible microfluidic structure, a first material, a second material, and an electrode arrangement. At least one of the first and second materials is a fluid. The structure defines at least one microfluidic chamber. The first and second materials are disposed in the chamber. The second material has a physical property and an electrical property different from the first material. The electrode arrangement includes at least one pair of electrodes spaced apart from each other with at least a portion of the at least one chamber located functionally directly therebetween such that at least one electronic property measured across the pair is based on a relationship between the second material and the electrode pair. The relationship is based on a physical condition of the microfluidic structure.

Abstract: An acceleration sensor includes an outer frame body, a heating element, a first temperature sensing element for temperature measurement and a second temperature sensing element for temperature measurement, and an operational amplifier. In the outer frame body, a fluid chamber capable of sealing a fluid inside thereof is formed. The heating element is formed on a circuit mounting surface which is a specific inner wall surface of a plurality of inner wall surfaces defining the fluid chamber. The first temperature sensing element and the second temperature sensing element are formed on the circuit mounting surface. The distance from the first temperature sensing element to the heating element is shorter than the distance from the second temperature sensing element to the heating element. The operational amplifier calculates a difference between a measurement result by the first temperature sensing element and a measurement result by the second temperature sensing element.

Abstract: Technologies are generally described for detecting acceleration by sensing a movement of a liquid contained in at least one liquid flow path arranged in a film-type material. An example device may be configured to detect acceleration based at least in part on an output signal from at least one strain sensor formed on at least one surface of a film layer. The film layer may include at least one liquid flow path containing a liquid and arranged in the film layer. The strain sensor may be formed on the at least one surface of the film layer in the vicinity of the least one liquid flow path, and may be configured to detect deformation on the at least one surface of the film layer.

Abstract: A device for increasing the magnetic flux density includes a semiconductor body and a first magnetic sensor integrated into the semiconductor body, whereby a housing section, which forms a cavity, is arranged above the sensor on the semiconductor surface and the cavity is filled with a ferromagnetic material and the material comprises a liquid.

Abstract: A sensor includes a housing and a mass, suspended in the housing. The motion of the mass emulates dynamic behavior of a brain of the wearer along a plurality of axes. At least one sensing element is coupled to generate sensor data based on the motion of the mass, in response to an impact to a protective helmet.

Abstract: A thermal convection type linear accelerometer includes a substrate and a first sensing device. The first sensing device includes two first temperature-sensing components and a first heater. The two first temperature-sensing components are disposed on the substrate. The first heater is disposed on the substrate. The first heater is located between the two first temperature-sensing components. The two first temperature-sensing components are higher than the first heater relative to the substrate.

Abstract: Technologies are generally described for detecting acceleration by sensing a movement of a liquid contained in at least one liquid flow path arranged in a film-type material. An example device may be configured to detect acceleration based at least in part on an output signal from at least one strain sensor formed on at least one surface of a film layer. The film layer may include at least one liquid flow path containing a liquid and arranged in the film layer. The strain sensor may be formed on the at least one surface of the film layer in the vicinity of the least one liquid flow path, and may be configured to detect deformation on the at least one surface of the film layer.

Abstract: A thermal convection type angular accelerometer includes an insulating substrate and an angular acceleration sensing device. The angular acceleration sensing device is disposed on the insulating substrate. The angular acceleration sensing device is configured to measure an angular acceleration of a rotation axis. The angular acceleration sensing device comprises a sensing group. The sensing group comprises two temperature sensing members and a heater disposed between the two temperature sensing members. The distance between two ends of the two temperature sensing members near the rotation axis is greater than the distance between the other two ends of the two temperature sensing members that are farther from the rotation axis.

Abstract: An inertial sensor (16) includes a differential thermocouple (13) including first (4A) and second (4B) metal traces, a poly trace (6) with a first end connected to a first end of the first metal trace to form a first (?) thermocouple junction and a second end connected to a first end of the second metal trace to form a second (+) thermocouple junction. A gas mass (10) located symmetrically with respect to the thermocouple junctions is heated by a heater (8). Acceleration or tilting of the sensor shifts the relative location of the gas mass relative to the thermocouple junctions, causing differential heating thereof and generation of a corresponding thermocouple output signal.

Abstract: One embodiment includes an accelerometer system. The accelerometer system can include a Far-Off Resonance Trap (FORT) control system configured to generate an optical trapping beam. The system can also include a FORT accelerometer detection system including a FORT that is configured to trap a cluster of atoms based on the optical trapping beam. The FORT accelerometer detection system can also include an interrogation system configured to determine motion of the cluster of atoms along at least one axis resulting from an external acceleration in the at least one axis based on a relative phase shift of an optical probe beam through the cluster of atoms. The system can further include an acceleration processor configured to calculate the external acceleration in the at least one axis based on the relative phase shift of the optical probe beam.

Abstract: Acceleration and/or tilt sensor having a ferromagnetic fluid that is located in a receptacle, and the receptacle constitutes a neutral position for the fluid, and the fluid is permanently magnetized, and a magnetic field detector arrangement is located at the receptacle to detect a displacement of the fluid, wherein a portion of the fluid can be displaced relative to the receptacle from the neutral position to an operating position by an external force while maintaining a continuous surface with the portion of the fluid remaining in the neutral position, and the fluid returns to the neutral position after removal of the external force.

Abstract: A thermal convection-type accelerometer includes a first insulating substrate, a circuit formed on the first insulating substrate, a first acceleration-sensing device coupled with the circuit, and a first supporting layer attached on the insulating substrate. The first acceleration-sensing device includes two temperature-sensing components and a heater disposed between the temperature-sensing components. The temperature-sensing components and the heater are directly formed on the first supporting layer.

Abstract: An accelerometer includes an enclosure and a flowable material disposed in the enclosure, A signal representing a shape of a surface of the flowable material in the enclosure is developed and a circuit is responsive to the signal for deriving an indication of acceleration.

Abstract: An RFID, Bluetooth as well as zigbee based thermal bubble type angular accelerometer includes a flexible substrate, a base layer, at least one cavity, and at least one sensing assembly. The base layer is formed on the flexible substrate. The at least one cavity is formed on the base layer. The at least one sensing assembly is suspended over the at least one cavity. The sensing assembly comprises a heater and two temperature sensing elements, wherein the two temperature sensing elements are substantially symmetrically disposed on opposite sides of the heater, and the heaters and the two temperature sensing elements extend in a radial direction.

Abstract: An RFID based thermal bubble type accelerometer includes a flexible substrate, an embedded system on chip (SOC) unit, an RFID antenna formed on the substrate and coupled to a modulation/demodulation module in the SOC unit, a cavity formed on the flexible substrate, and a plurality of sensing assemblies, including a heater and two temperature-sensing elements, disposed along the x-axis direction and suspended over the cavity. The two temperature-sensing elements, serially connected, are separately disposed at two opposite sides and at substantially equal distances from the heater. Two sets of sensing assemblies can be connected in differential Wheatstone bridge. The series-connecting points of the sensing assemblies are coupled to the SOC unit such that an x-axis acceleration can be obtained by a voltage difference between the connecting points. The x-axis acceleration can be sent by the RFID antenna to a reader after it is modulated and encoded by the modulation/demodulation module.

Abstract: To provide a small-sized liquid seal sensor that can enhance degrees of freedom in detection directions. A liquid seal sensor having a liquid seal part that seals a liquid therein, and a detecting part that detects changes in the liquid sealed in the liquid seal part has a configuration in which the detecting part detects changes in the liquid sealed in the liquid seal part, and thus when an acceleration is applied, the detecting part detects changes in the liquid sealed in the liquid seal part, whereby the sensitivity to accelerations can be enhanced in any directions.

Abstract: Microstructures can be formed as patterned layers on a substrate and then erecting the microstructures out of the plane of the substrate. The microstructures may be formed over circuits in the substrate. In some embodiments the patterned layer provides resiliently-flexible members such as cantilevers or springs that can be buckled to permit an edge defined by the patterned layer to engage a surface of the substrate. In some embodiments deformation of the resiliently-flexible members results the edge being forced against the substrate. Such microstructures may be applied in a wide range of applications including supporting optical elements, sensors, antennas or the like out of the plane of a substrate. Examples of accelerometer structures are described.

Abstract: This application is directed to a shock sensor mounted in an electronic device. The shock sensor includes both active and passive shock detection methods that allow a technician to determine whether the electronic device was subjected to a shock event that exceeded an impact threshold level. The shock sensor may include shock detection contacts that form an electrical circuit that remains open in the absence of a shock event that exceeds an impact threshold level. In response to a significant shock event, a movable component or substance of the shock sensor may move from a first position to a second position, thereby closing the electrical circuit formed by the shock detection contacts. The change in circuit may be detected and used to provide active indication of whether the electronic device has been subjected to a substantial shock event. In addition, the shock sensor may be observed to passively determine whether the electronic device has been subjected to a substantial shock event.

Abstract: The technical solution provided can be implemented with the help of two miniature vessels and even one miniature vessel filled with the flowing media. It is based on determining the pressures difference in particular points, wherein the pressures caused by the cross accelerations and other disturbance factors are considered to be equal, and the ones caused by the acceleration determined are considered to be different. The present solution enables one to determine the acceleration with higher accuracy even with big tilting (practically up to 360°) of the platform, in particular, on the body of a moving object, the acceleration whereof is determined.

Abstract: An accelerometer includes a pressure transducer; and a vibration-to-pressure converter (VPC). The VPC may include a housing mechanically coupled to an object to be measured, and a diaphragm sealing the housing to form a chamber, the chamber being fluidly coupled to the pressure transducer. A power generator and motor including the accelerometer are also presented.

Abstract: The present technical solution provided allows it to determine true meridian of any movable object. This solution is based on determining true meridian by zero value of linear acceleration induced created by changing the projection of the vector of linear velocity, caused by rotating any heavenly body, in particular, the terrestrial globe. The determination is implemented in compact variant only by the devices located on the movable object without any necessity of using induced radiations, quickly and accurately without any necessity of knowing the coordinates of location and the speed of movement irrespective of weather conditions, transverse accelerations, temperature changes and external magnetic fields influence.

Abstract: A closed-loop heater control circuit for use with integrated circuit thermal sensing devices, such as thermal accelerometers, is disclosed. The heater control circuit includes a switched-capacitor integrating circuit and a controller or modulator. The switched-capacitor integrating unit integrates a common-mode voltage signal from an instrument amplifier with respect to an analog common reference voltage. In operation, the switched-capacitor integrating unit is adapted so that the closed-loop is opened briefly at the beginning of every new cycle, e.g., using an enable signal, during fast start-up or power-down.

Abstract: The present technical solution for determining linear acceleration, the vector whereof is considered to be at a tangent to a trajectory of movement of a moving object, is based on determining new differences of accelerations. It is considered to be the basis for efficient, accurate, with the threshold of sensitivity equal to zero in small-size option solving the tasks of autonomous navigation, piloting, stabilization and etc. Said solution is irrespective of disturbance factors, in particular, cross-axis and centrifugal accelerations, vibrations, temperature and others, and can be used without any gyroscopes.

Abstract: Disclosed is an electrowetting device. The electrowetting device includes a conductive or polar liquid material, and an electrode applying voltage to the liquid material through a dielectric layer. In the electrowetting device, the dielectric layer is formed as an anodized portion made of a metal oxide formed by anodizing the electrode, and a voltage applying unit applying voltage between the electrode and the liquid material and a polar capacitor are placed between the electrode and the liquid material.

Abstract: An inertial measurement unit comprises a mounting plate with an opening therethrough, and a sensor assembly disposed in the opening of the mounting plate. Upper and lower support shells having shell flanges are attached to upper and lower surfaces of the mounting plate. The upper and lower support shells surround the sensor assembly. A plurality of gas bearing pads each extends through apertures in the upper and lower support shells. Upper and lower gas plenums have plenum flanges attached to the shell flanges of the upper and lower support shells, with the upper and lower gas plenums surrounding the upper and lower support shells. Pressure relief valves are coupled to the plenum flanges of the upper and lower gas plenums. The gas bearing pads and the sensor assembly are separated by a gap when pressurized gas is fed into the upper and lower gas plenums, thereby creating a gas bearing that allows the sensor assembly to be freely suspended and rotated in all directions.

Abstract: This invention relates to high precision, fluid-containing, transducer-based accelerometers that are capable of measuring acceleration, inclination, position and velocity by measuring the electronic response of a transducer to fluid flow caused by external acceleration or by free convection. The accelerometers of this invention are capable of varying the local density of the fluid, thereby creating a volume of fluid with a lower or higher density compared to the rest of the fluid in the accelerometer. The movement of this volume of lower or higher density fluid as a result of external acceleration is measured to determine the external acceleration.

Abstract: An acceleration sensor, which has realized such a high impact-resistance that a weight bottom surface of an acceleration sensor element does not directly collide with an inner bottom plate of a protection case made of ceramic, glass or silicon to avoid edges and corners of the weight bottom surface of the acceleration sensor element chipping, even when an excessive acceleration or impact is applied to the acceleration sensor. The acceleration sensor comprises the acceleration sensor element having in a center a weight that works as a pendulum when acceleration is applied, and the protection case housing the acceleration sensor element. The inner bottom plate of the protection case works as a regulation plate to prevent the weight from excessively swing downwards. An impact buffer material of a metal layer or a resin layer is provided on the weight bottom surface or the inner bottom plate of the protection case.

Abstract: A closed-loop heater control circuit for use with integrated circuit thermal sensing devices, such as thermal accelerometers, is disclosed. The heater control circuit includes a switched-capacitor integrating circuit and a controller or modulator. The switched-capacitor integrating unit integrates a common-mode voltage signal from an instrument amplifier with respect to an analog common reference voltage. In operation, the switched-capacitor integrating unit is adapted so that the closed-loop is opened briefly at the beginning of every new cycle, e.g., using an enable signal, during fast start-up or power-down.

Abstract: An apparatus includes: a fluid container; a fluid mixture disposed within the fluid container, the fluid mixture including at least two components having different relative dielectric constants or different relative permeabilities; an imparter for imparting an electrostatic or electromagnetic force across the fluid mixture to cause at least one of the components to be placed in motion; and a controller for controlling the electrostatic or electromagnetic force to counteract the effects of an applied acceleration. A method includes positioning a high dielectric or high permeability element suspended in a low dielectric or low permeability fluid contained between a pair of charged electrode plates or a magnetic gap; determining a change in capacitance or inductance of the apparatus; and determining from the capacitance change or inductance change a magnitude of the acceleration.

Abstract: To provide a small-sized liquid seal sensor that can enhance degrees of freedom in detection directions. A liquid seal sensor having a liquid seal part that seals a liquid therein, and a detecting part that detects changes in the liquid sealed in the liquid seal part has a configuration in which the detecting part detects changes in the liquid sealed in the liquid seal part, and thus when an acceleration is applied, the detecting part detects changes in the liquid sealed in the liquid seal part, whereby the sensitivity to accelerations can be enhanced in any directions.

Abstract: The invention relates to construction principles, operating and manufacturing methods for inertial sensors, i.e., sensors for rapidly detecting movement and acceleration in all degrees of freedom in space, and for separately detecting the position with respect to the perpendicular under the action of acceleration due to gravity. Use is made of the knowledge that to maintain a common convection zone of two or more sensor elements, the power fractions supplied to these elements vary with change in position, movement and acceleration.

Abstract: The acceleration measurement system has a first thermal cell optimized in sensitivity and a second thermal cell optimized in passband, which cells are connected to inputs of a servo-control loop including an amplifier presenting gain that varies as a function of input signal frequency.

Abstract: A thermal accelerometer comprising two detector strands having resistivity that is temperature sensitive, a detector member for detecting a temperature difference between the detector strands, a feedback member for establishing temperature equilibrium between the detector strands by supplying the detector strands with pulse feedback signals of variable width, a member for calculating acceleration, and a multiplexer member connected to the detector strands, to the detector member, and to the feedback member so as to perform the following in alternation: measuring the temperature difference between the detector strands; and providing the detector strands with the feedback signals, the widths of the pulse signals being determined by comparing a sawtooth signal with DC signals representative of the temperature difference between the detector strands.

Abstract: Single chip 3-axis thermal accelerometer devices include a substrate, at least one cavity etched in the substrate, a fluid disposed in the cavity, a bridge structure suspended over an opening of the cavity, and a plurality of heater elements and temperature sensing elements disposed on the bridge structure. The substrate has a substantially planar surface defined by X and Y coordinate axes, and the bridge structure is suspended over the opening of the cavity in the X-Y plane. In one embodiment, the bridge structure is configured to position at least two of the temperature sensing elements out of the X-Y plane. The heater and temperature sensing elements are disposed on the bridge structure in optimized arrangements for providing reduced temperature coefficients and for producing output voltages having reduced DC offset and drift.

Abstract: This invention relates to high precision, fluid-containing, transducer-based accelerometers that are capable of measuring acceleration, inclination, position and velocity by measuring the electronic response of a transducer to fluid flow caused by external acceleration or by free convection. The accelerometers of this invention are capable of varying the local density of the fluid, thereby creating a volume of fluid with a lower or higher density compared to the rest of the fluid in the accelerometer. The movement of this volume of lower or higher density fluid as a result of external acceleration is measured to determine the external acceleration.

Abstract: A thermal accelerometer device that allows up to three axes of acceleration sensing. The thermal accelerometer includes a substantially planar substrate, a cavity formed in the substrate, a heater element, and at least first and second temperature sensing elements. The heater element is suspended over the cavity, and the first and second temperature sensing elements are disposed along the X or Y axis in the substrate plane on opposite sides of and at equal distances from the heater element. The thermal accelerometer employs differential temperatures detected by the temperature sensing elements to provide indications of acceleration in the X or Y directions. Further, the thermal accelerometer employs a common mode temperature detected by the temperature sensing elements to provide an indication of acceleration along a Z axis perpendicular to the X and Y axes.

Abstract: A capacitance type liquid sensor is disclosed which detects a tilt angle and acceleration of an object using the fact that a liquid surface always keeps itself horizontal. Openings (13, 14) are formed in two sides of a hollow cylindrical closed container (6) made of an electrically insulating material, and the container has two parallel sides (2, 3). Plate-shaped main electrodes (4, 5) on at least one face of each of which silicon oxide film is formed are made to be in contact with the sides so as to close the openings, with the silicon oxide film being placed so as to face the inside of the container. A sealing agent (28) is interposed in a gap between the plate-shaped main electrodes and the sides. The container is filled with electrically conductive liquid (27) of an amount equal to substantially one-half of the inside volume of the container. An auxiliary electrode (8) brought into electrical contact with the conductive liquid is mounted in the container.

Abstract: A thermal accelerometer device that provides a compensation for sensitivity variations over temperature. The thermal accelerometer includes signal conditioning circuitry operative to receive analog signals representing a differential temperature is indicative of a sensed acceleration. The signal conditioning circuitry includes serially connected A-to-D and D-to-A converters, which implement a temperature dependent function and process the received signals to provide a compensation for sensitivity variations over a range of ambient temperature. To provide a ratiometric compensation for variations in power supply voltage, a buffered voltage proportional to the supply voltage is provided as a reference voltage to the D-to-A converter. The thermal accelerometer includes a self-test circuit for verifying the integrity of a heater, temperature sensors, and circuitry included within the device.

Abstract: The thermal accelerometer of the invention comprises an enclosure having disposed therein a central filament powered by alternating electric current of zero mean amplitude and having a frequency lying between first and second resonant modes of vibration of the central filament, the central filament lying between detector filaments adjacent to reaction filaments powered by alternating electric current of zero mean amplitude and having a frequency lying between the first and second resonant modes of vibration of the reaction filaments.

Abstract: A micro-accelerometer includes first and second closed cavities, into each of which an equal quantity of gas is introduced. A membrane partitions the symmetrical first and second cavities. Temperature sensors are provided within the first and second cavities, respectively, to measure the gas temperatures within the cavities. Difference of temperature is not caused so long as no acceleration affects the inner side of the cavities. However, if a linear acceleration is applied, the membrane is deformed in the direction of acceleration, whereby for example, the gas within the first temperature is compressed and its temperature increases, whereas the temperature of the second cavity decreases because the gas is expanded within the second cavity. The difference of gas temperatures between the first and second cavities is measured as a variation of electric power resistance by the temperature sensors and applied as a function of acceleration.

Abstract: A disc or like article (10, 115, 119) rotatable by drive means, such as a compact disc for use with a computer, includes indication means (12, 110, 120) which, when the disc is rotated at or above a predetermined angular velocity, provide an indication that rotation has occurred, which indication can be important if the disc contains confidential information. The indication device can be a tube formed with two enclosures separated by a breakable membrane (15, 16, 112, 122), a colored liquid/gel (17, 111 121) being in one enclosure and passing into the second enclosure, by breaking the membrane, when the disc is spun, thereby providing a visual indication thereafter of the spinning having occurred The invention also relates to such an indication means, per se, for after-fitting to a disc recorded on by spinning, and to a method of producing a disc with said indication means.

Abstract: The device for measuring horizontal acceleration consisting of two similar hermetically sealed vessels containing liquid and provided with the pressure sensors connected to the differential scheme. The determination of the accelerations is done in terms of these sensors signals difference, which measuring the pressure in particular points. In these very points the pressures created by the vertical acceleration are equal in terms of each other, the ones created by the horizontal acceleration are different.

Abstract: An integrated convective accelerometer device. The device includes a thermal acceleration sensor having a thermopile and a heater element; control circuitry for providing closed-loop control of the thermopile common-mode voltage; an instrumentation amplifier; clock generation circuitry; voltage reference circuitry; a temperature sensor; and, output amplifiers. The device can be operated in an absolute or ratiometric mode. Further, the device is formed in a silicon substrate using standard semiconductor processes and is packaged in a standard integrated circuit package.

Abstract: A thermal bubble type micro inertial sensor formed by micromachining technology includes a substrate, a heater arranged on the substrate, four temperature sensing members, a cap arranged above the substrate to cover and encapsulate the heater and the temperature sensing members, and a liquid filled into a chamber formed between the cap and the substrate. The temperature sensing members are symmetrical arranged at opposite sides of the heater and on the substrate, respectively, to sense the temperature difference beside the heater. The heater heats and partially vaporizes the liquid to form a thermal bubble in the liquid environment. Controlling the liquid characteristics and heater temperature may control the bubble size and enable the temperature sensing members to sense the temperature distribution variation. The sensor may serve as an inclinometer to sense the tilt, as well as an accelerometer to measure the acceleration.

Abstract: A sensor for detecting a rotational movement or an angular acceleration has at least one heating element and at least one sensor element and a fluid surrounding the heating element and the sensor element, the heating element producing in the fluid a convection flow zone through which an isothermal field is defined. The heating element and the sensor element are arranged with respect to an axis of rotation of the rotational movement or of the angular acceleration to be detected, in such a way that the sensor element is displaced relative to the isothermal field when a rotational movement or an angular acceleration takes place.

Abstract: An ionization contact potential difference gyroscope including a housing enclosing a first and second electrode with a gas, further including an ionization source capable of providing ions from the gas, and a contact potential difference measurement circuit that is capable of measuring an electrical signal related to the amount of ions striking at least one of the two surfaces. The measurement circuit of the present invention is capable of sensing the small amount of electrical current flowing as the electrons and ions strike one or both of the surfaces.

Abstract: An accelerometer has a substrate with a cavity therein, a heater extending over the cavity, and a pair of temperature sensitive elements each spaced apart from the heater a distance of 75-400 microns also extending over the cavity. On passing an electrical current through the heater a symmetrical temperature distribution is set up on both sides of the heater. On acceleration, this distribution moves and by measuring the temperature as sensed by the pair of temperature sensitive elements the acceleration that caused the shift can be calculated.