Abstract: A drive location compensation system determines a deviation between an actual and nominal position of a drive location on a rotor relative to an attachment location on the rotor. The compensation system uses a balancing machine and a sensor that detects when one of the attachment locations passes a known position. Based on the output of the sensor and a known position of a drive spindle of the balancing machine that is coupled to the drive location on the rotor, a relation between the drive spindle and the attachment location is determined. This relationship is compared to a nominal relationship that is based on a calibration standard. The deviation is compensated for during the balancing or the rotor.

Abstract: A method and apparatus accurately measuring the amount of unbalance of a disc, based on the time to reach a target RPM (Rotation Per Minute) regardless of an assembly condition of a disc drive. The method includes: storing a plurality of reference disc unbalance values; measuring an RPM (Rotation Per Minute) of the disc; comparing the measured RPM with a target RPM; and when the measured RPM reaches the target RPM, detecting a reference disc unbalance value among the plurality of reference disc unbalance values based on an elapsed time to reach the target RPM. Accordingly, the amount of disc imbalance of the disc can be constantly measured regardless of an assembly condition of the disc drive and the computer.

Abstract: The machine determines, by first measurement sensor means (30), the axial position of at least one transverse balancing plane (P1, P2) in which the operator chooses to apply a respective balancing mass, and the radial position of points on the application surface (11a) corresponding with said balancing plane (P1, P2), while the machine monitors the angular position of the body (10); the body (10) is rotated and by suitable means the machine determines the imbalance means together with the data originating from the first and second sensor means, the value of each balancing mass and the position of its point of application on the application surface (11a) being determined.

Abstract: A method for determining the density of a fluid in a pipe. The method includes determining a first, second, and third reference reading of a pipe using a transmitter transducer, a receiver transducer, and a primary receiver transducer. The first reference reading is determined when the pipe is empty. The second reference reading is determined when the pipe contains a reference liquid of known sonic impedance. The third reference reading is determined when the pipe contains an unknown liquid. The liquid sonic propagation velocity of the unknown liquid is measured. The relationship of an impedance of the unknown liquid in relation to the impedance of the reference liquid is determined. Finally, the density of the unknown liquid is determined using the determined relationship of the unknown impedance to the known impedance of the reference liquid divided by the measured liquid sonic propagation velocity of the unknown liquid.

Abstract: An acceleration sensor includes a first resonator and a second resonator which resonate at independent frequencies and each of which includes a piezoelectric body and electrodes arranged on both main surfaces thereof, and a first base plate and a second base plate. A first unimorph type acceleration detection element includes the first resonator bonded to one surface of the first base plate, and a second unimorph type acceleration detection element includes the second resonator bonded to one surface of the second base plate. Each of the first and second unimorph type acceleration detection elements is fixed at one longitudinal end thereof or opposed longitudinal ends thereof such that the first resonator and the second resonator are diametrically opposed to each other or are arranged to face each other to allow the first resonator and the second resonator to independently deflect in response to the application of acceleration.

Abstract: A vibration sensor having a pressure sleeve in which the pressure sleeve may be mounted under pressure on a component causing vibration. To detect a vibration signal, e.g., in the case of a knock sensor, a sensory system is held by a seismic mass above it on the outside of the pressure sleeve via a screw connection on a contact face of the pressure sleeve under an axial prestress in the direction of the sensory system. The seismic mass has an inside thread and may be screwed onto the sensory system to produce the axial prestress in the direction of the sensory system. A seismic mass or the sensory system has at least two opposing grooves running radially opposite one another, so that the plastic may enter an interior space between the sensory system and the pressure sleeve during extrusion through these grooves.

Abstract: By applying a first value of voltage to a first side of a MEMS gyroscope and applying a second value of voltage to a second side of the MEMS gyroscope, the start time of the MEMS gyroscope may be improved. The first and second value of voltage may be provided by a bias power source, such as a battery or a super capacitor. The first value of voltage may be substantially equal in magnitude to and opposite in polarity to the second value of voltage. The bias power source may also be applied to drive electronics connected to the MEMS gyroscope. The bias power source may prevent amplifiers within the drive electronics from saturating during the start time.

Abstract: An apparatus for balancing wheels includes a chassis, a driven shaft extending from the chassis for rotating the wheel, a wheel mounting accessory operably mounted on the driven shaft for use in mounting the wheel, and an accessory storage device rotatably mounted on the chassis for storing the accessory when not in use.

Abstract: A method for locating gas leaks from underground gas pipelines in which a first acoustic sensor having a first signal output is positioned in ground disposed substantially above or at a distance from the underground gas pipeline. At least one second acoustic sensor having a second signal output is positioned in the ground at a plurality of locations substantially above the underground gas pipeline. The output signals from the acoustic sensors are measured for each location of the second acoustic sensor and the signals are adaptively filtered to remove common noise signal components. The statistical minima of these rms voltages are determined for both the first output signal and the adaptively filtered second output signals and the differences determined. The location of the second acoustic sensor corresponding to the largest positive said difference is the location closest to the leak site.

Abstract: An acceleration sensor includes a bimorph type acceleration detection element including a first resonator and a second resonator, each resonator formed of a piezoelectric body and having electrodes arranged on both main surfaces thereof, and an intermediate layer. The acceleration detection element is produced by bonding the first resonator and the second resonator with the intermediate layer interposed therebetween. The acceleration detection element is supported at one longitudinal end or opposed longitudinal ends thereof so that the first and second resonators are integrally deflected under acceleration. The intermediate layer is hard enough to transfer flexural stress in one of the first and second resonator to the other of the first and second resonators and the vibration of the one of the first and second resonators is attenuated when the vibration is transmitted from the one to the other of the first and second resonators.

Abstract: A damping gyrometer comprised of at least two and preferably four rotating paddles attached to a common central elevated low-friction pivot point via rising radial arms. A stand with a concave glass element provides a low-friction support as a pivot point seat for the pivot point. All elements of the apparatus are non-conductive. Once set into motion, the only force acting on the gyrometer are the pivot point friction and the damping effects of the medium in which it spins. A laser beam and photodetector (or alternatively a laser displacement sensor), along with customized software algorithms are used to measure the rotational rate and, hence, the deceleration rate of the apparatus which can then be used to determine properties of the medium in which it spins, including changes in density, pressure, and temperature. The measurement can also be directly related to the electron density in the case of weakly ionized gases.

Abstract: A resonant sensor comprises a support structure comprising two support points; a laminar resonator suspended between said two support points of said support structure and comprising a plurality of substantially parallel flexural members which are responsive to relative movement of said support points; means for exciting said resonator into a balanced mode of oscillation and means for sensing motion of said resonator. Said means for sensing motion of said resonator is or are spaced from, and linked to, said flexible area of said resonator by means of levers. Said support points are preferably adapted to move relative to each other in response to a difference in pressure, force or acceleration.

Abstract: The disease scoliosis is a rotational deformity of the spine and ribs, characterized by both lateral curvature and vertebral rotation. Idiopathic genetic scoliosis occurs about seven time more frequently in the female than in the male and accounts for about 80% of all cases of the disease. The deformity first appears in infants, juveniles or adolescents generally, and many school health programs in this country have screening programs for the early detection of the disease. On detection, the patient is referred to a specialist for treatment. Presently, however, over-referral of great numbers of children with very mild curvatures which do not require treatment is causing a large number of unnecessary x-rays and needless lost time and expense. The invention disclosed herein is a simple and convenient device for measuring the clinical deformity in patients with scoliosis which establishes objective criteria for screening and which can significantly reduce the number of over-referrals.

Abstract: An electronic device for measuring relative angular positional displacement and angular range of motion for body segments and articulating joints of the human skeleton is disclosed. The device has a hand-held interface unit which is placed against the body segment or joint to be tested. Mounted within the housing of the interface unit is a shaft with a pendulum at one end and an optical encoder at the other. As the body segment rotates or the joint articulates, the pendulum swings in the direction of gravity, causing the shaft to rotate. The optical encoder generates an electrical signal representative of the amount of rotation of the shaft. The generated signal is fed to a microprocessor which processes the information and can produce on a display the change in angular position relative to initial angular position or the angular range of motion of the body segment or articulating joint.

Abstract: A measuring probe for the invasive measurement of blood parameters such as pH, pO.sub.2 or pCO.sub.2 comprises one or more optical fibers in a tubing. These optical fibers end up in sensors which are surrounded by a sheath. An additional wire is guided both in the tubing and the sheath. At the proximal end of the probe, the wire is connected to locking means closing the sheath at its outer end, whereas, at the distal end thereof, the wire is fastened to the tubing or to a connector. Therefore, this wire ensures perfect strain relieving of the probe.

Abstract: A sensor for measuring fluid concentrations or the temperature of body. A fiber-optic catheter having a fluorometric sensor attached at a distal end is excited by a light source outside the body. The sensor fluoresces with an intensity or with a lifetime related to the concentration of the fluid or the temperature. The catheter has one light pipe for exciting the sensor and a second light pipe for generating a reference signal to calibrate signals from the fluorometric sensor. One embodiment has two sensors that fluoresce with different intensities and lifetimes to simultaneously give information about both the temperature and the fluid concentration.

Abstract: Optical probes for the invasive measurement of blood parameters consist of at last one sensor, each of these sensors having a diffusion zone with a selective membrane. The sensor or the sensors are surrounded by a stabilizing sheath. This sheath is to be fastened on sensor(s) by a glue. A silicone glue provides the feature that gas molecules can diffuse through it; therefore, blood gas sensors such as pO.sub.2 sensors or pCO.sub.2 sensors may be completely embedded in said glue. If a pH sensor is used, it must be placed in the top position of the horizontally lying sheath during manufacturing. The silicone glue then does not cover the diffusion zone of the pH sensor completely. Further, silicone glue provides additional elasticity which improves sensor characteristics.

Abstract: A device for analyzing fluorescent light signals consists of memory means for storing as a reference spectrum a spectrum obtained under predetermined conditions, and extraction means for extracting a predetermined component spectrum based on the results of a conversion of the reference spectrum using a specific wavelength of a measured spectrum obtained during actual measurement and a specific wavelength of the reference spectrum. The arrangement of the invention allows the spectrum of a specific component to be extracted accurately from measured spectra.

Abstract: A method of detecting pre-malignant lesions in the gastrointestinal tract comprises positioning an opitcal fiber in a patient's gastrointestinal tract and transmitting ultraviolet laser light through said optical fiber means to cause the tissue of the gastrointestinal tract illuminated by the laser to fluoresce in the near visible band of frequencies. The fluorescence spectrum is returned through the optical fiber to a spectrum analyzing means which analyzes the spectrum in the wavelength range of 350 to 700 nm to determine whether the tissue caused to fluoresce is pre-malignant. Tissue so diagnosed may be ablated by a high power laser using the same fiberoptic system.

Abstract: A transducer element particularly adapted for use in an apnea detection system is formed of resilient conductive material having an electrical impedance which varies in response to breathing movement of an infant. A control detects the varying impedance and generates an alarm signal whenever variations caused by breathing movements fall below a predetermined level.