Abstract:
Described herein are ruggedized wafer level MEMS force dies composed of a platform and a silicon sensor. The silicon sensor employs multiple flexible sensing elements containing Piezoresistive strain gages and wire bonds.
Abstract:
A load suspension and weighing system for a removable reservoir unit of a portable dialysis machine includes a centrally located flexure assembly. The flexure assembly includes magnets and a number of flexure rings which allow for movement of the magnets about a fixed circuit board. Sensors in the circuit board sense changes in the magnetic field as the magnets move in relation to the circuit board. The magnetic field changes produce a voltage output which is used by a processor to generate weight calculations. The top of the flexure assembly is attached to the interior of the dialysis machine. The entirety of the reservoir unit is suspended by a first internal frame that is attached to the bottom of the flexure assembly. Having a single flexure assembly positioned above the reservoir unit provides more accurate weight measurements while also preventing damage to the assembly from water spillage.
Abstract:
Force plate (1) having a plate-shaped carrier (2) which, when arranged vertically, has an upper carrier section (3) at the top in the vertical direction and a lower carrier section (4) at the bottom in the vertical direction. A first end carrier section (5) is connected, on the one hand, to the upper carrier section (3) via a vertical rod (7) and, on the other hand, to the lower carrier section (4) via a horizontally oriented spring element (6). That end of the lower carrier section (4) which faces away from the first end carrier section (5) is connected to the upper carrier section (3) via a horizontal rod (8). A second end carrier section (15) connects the horizontal rod (8) to the lower carrier section (4) via a vertically arranged spring element (16).
Abstract:
A detection circuit for detecting changes in capacitance. The detection circuit includes a tuned ratio circuit and an alternating current (AC) source AC-coupled to the tuned ratio circuit. The tuned ratio circuit includes first and second tuned circuits that are tuned to, or close, to the frequency of the AC source. Output circuitry is coupled between the two tuned circuits. During use as a transducer, an active capacitive transducer is inductively coupled to the first tuned circuit. Changes in the capacitance of the active capacitive transducer cause changes in the tuning of the first tuned circuit. The output circuitry generates an output signal that is a function of the difference between the tunings of the first and second tuned circuits.
Abstract:
A flow velocity detector for detecting a flow velocity of a fluid flowing through a flow passage is provided, the flow velocity detector including a flow passage-forming section which defines the flow passage; a stress light-emitting section which is arranged at the flow passage-forming section to receive a stress having a magnitude depending on the flow velocity of the fluid and which emits a light of which amount corresponds to a change of the received stress; and a light-receiving sensor which receives the light emitted by the stress light-emitting section. The flow velocity of the fluid is detected based on an amount of the light received by the light-receiving sensor to generate a detection signal. Accordingly, the structure is simple and small-sized, and the flow velocity of the fluid can be detected at low cost.
Abstract:
A piezoelectric flexural sensing structure having increased sensitivity and decreased noise, without sacrifice of the sensor bandwidth. The structure is made up of a proof mass, a beam with a base and optionally having castellated bonding surfaces and two poled bonding mode PMN-PT crystal plates mounted on the beam.
Abstract:
The invention is a microfabricated silicon cantilever with a stiffness appropriate to resolve forces of interest in working with micro objects. Stiffnesses may range from about 10 piconewtons per micron of deflection, to about 1 millinewton per micron of deflection. There is a set of micro weights of appropriate masses that is used to calibrate the force gages. The weights are captive to a ring on a handle so that they are free to move, but will not get lost.
Abstract:
A force measuring device for seat weight determination in a motor vehicle, comprising a taking up element which has at least two bearing points spaced from one another and arranged so that one of the bearing points is loadable with a force to be measured perpendicularly relative to a longitudinal axis of the taking up element, means forming a first recess in the taking up element in a region between at least two bearing points, a rod-shaped element which extends in the longitudinal axis of the taking up element and is not loaded by bending forces, the rod-shaped element having a free end which deviates from the longitudinal axis of the taking up element when a force to be measured acts on the taking up element, and a measuring unit for detecting the deviation of the free end of the rod-shaped element, the measuring unit having a magnet and a magnetic field-sensitive sensor, the magnet and the magnetic field-sensitive sensor being arranged immovably relative to one another and the magnet is arranged close at a distance to a ferromagnetic material so that the distance from the magnet to a ferromagnetic material changes under a loading with the force to be measured.
Abstract:
A circuit board, which includes one or more sensors, is integrated in a fluid control device, such as a valve manifold and a base plate. The fluid control device selectively directs a fluid used to control pneumatic or hydraulic equipment. The sensors are used to measure physical characteristics of the fluid, such as flow rate, pressure, and temperature. A flow sensor includes a paddle and a support member. The paddle is disposed at least partially in an orifice and is displaced in response to fluid flow. The support member positions the paddle in the orifice and includes a plurality of strain gauges. The strain gauges are disposed on only one side of the support member and are mechanically stressed in response to the paddle being displaced by the fluid flow.
Abstract:
An ultrananocrystalline diamond (UNCD) element formed in a cantilever configuration is used in a highly sensitive, ultra-small sensor for measuring acceleration, shock, vibration and static pressure over a wide dynamic range. The cantilever UNCD element may be used in combination with a single anode, with measurements made either optically or by capacitance. In another embodiment, the cantilever UNCD element is disposed between two anodes, with DC voltages applied to the two anodes. With a small AC modulated voltage applied to the UNCD cantilever element and because of the symmetry of the applied voltage and the anode-cathode gap distance in the Fowler-Nordheim equation, any change in the anode voltage ratio V1/N2 required to maintain a specified current ratio precisely matches any displacement of the UNCD cantilever element from equilibrium. By measuring changes in the anode voltage ratio required to maintain a specified current ratio, the deflection of the UNCD cantilever can be precisely determined. By appropriately modulating the voltages applied between the UNCD cantilever and the two anodes, or limit electrodes, precise independent measurements of pressure, uniaxial acceleration, vibration and shock can be made. This invention also contemplates a method for fabricating the cantilever UNCD structure for the sensor.