258 results about "Rotational vibration" patented technology

A disk drive is disclosed comprising a disk, and a head actuated radially over the disk. A first linear acceleration signal is generated representing a first acceleration disturbance, a second linear acceleration signal is generated representing a second acceleration disturbance, and a third linear acceleration signal is generated representing a thermal popping disturbance. The first linear acceleration signal is combined with the third linear acceleration signal to generate a fourth linear acceleration signal representing a combined physical shock disturbance and thermal popping disturbance.

A method of reducing rotational vibration effects in a disk drive by sensing vibration in a sensor and generating corresponding sensor data; deriving a statistical sensor (SS) value based on the sensor data; deriving a statistical position error signal (SPES) value from servo sectors read by the head; comparing the SS value to a SS-threshold value; comparing SPES value to a SPES-threshold value; and generating a feed-forward command effort signal for reducing rotational vibration effects if the SS value exceeds the SS-threshold value and if SPES value exceeds the SPES-threshold value.

A method for reducing the effects of rotational vibration in a disk drive comprising generating a self-induced vibration in the disk drive, and sensing the self-induced vibration in the first and second sensors and generating a corresponding first and second sensor data. The method further comprises comparing the first and second sensor data to determine a gain-differential, and scaling at least one of the first and second sensor data to reduce the gain-differential between the first and second sensors.

Transducer (100, 200, 300, 500, 600) for converting mechanical vibrations to an electrical signal and/or for converting an electrical signal to mechanical vibration. Damping liquid (122, 222, 522, 622) damps the relative vibration of transducer components (110, 250, 252, 254, 510, 610). The damping liquid can be selected to optimize the sound quality of acoustic vibrations at the point of transduction. Also, a transducer with components that rotate relative to each other (304, 310, 504, 510, 604, 610). For example, a permanent magnet component may simultaneous vibrate rotationally and linearly with respect to an electric signal carrying coil. The characteristics of the rotational vibration may be adjusted to optimize sound quality of acoustic vibrations at the point of transduction.

A micro-electromechanical systems (MEMS) transducer (100, 700) is adapted to use lateral axis vibration to generate non-planar oscillations in a pair of teeter-totter sense mass structures (120/140, 720/730) in response to rotational movement of the transducer about the rotation axis (170, 770) with sense electrodes connected to add pickups (e.g., 102/107, 802/807) diagonally from the pair of sense mass structures to cancel out signals associated with rotation vibration.

A shaker movement permits an arbitrary path of motion in a shaker's shaking action. The shaker movement comprises independent control over the "X" and "Y" directions of the shaking actions by a pair of track assemblies, each track assembly comprising a pair of fixed rods and a pair of sliding rods that are interconnected with each other in a rectangular, grid-like pattern. Motion in both directions can be driven by a single motor utilizing independent pulley-and-belt systems or by two synchronized motors which are connected to a sliding rod of each track assembly. By altering the relative amplitude, phase angle, and frequency between the "X" and "Y" directions, the shaking action can follow a desired path. The shaker path can be varied from the traditional circular orbital motion or linear motion, to a new group of shaking patterns in which the direction of the shaking movement can reverse. The new patterns of shaker movement cause the liquid being shaken to be more thoroughly mixed, with less power input, and at a lower angular frequency than is practical with traditional paths of motion. This results in higher rates of gas transfer to and from the liquid, resulting in greater growth of a bacterial culture, and for higher rates of mass transfer at equivalent levels of energy input.

A power transmitting apparatus which can suppress the rotational vibrations by suppressing rotation of the pressure member relative to the clutch member is provided. The power transmitting apparatus can comprise a clutch housing rotatable together with an input member and a plurality of driving-side clutch discs mounted thereon; a clutch member with a plurality of driven-side clutch discs mounted thereon and interleaved with the driving-side clutch discs; and a pressure member axially movably relative to the clutch member to increase or release the press-contacting force acting on the driving-side clutch discs and the driven-side clutch discs. The power transmitting apparatus can further comprise one or more slide-suppressing members for applying sliding resistance to the pressure member when the pressure member is rotated relative to the clutch member.

A resonator micro-electronic gyro, preferably a micro-electromechanical system (MEMS) gym comprises a first and a second resonator mass (1, 2) suspended for rotational vibration. The two masses (1, 2) are flexibly connected by four mechanical coupling elements (4, 5, 6, 7) for anti-phase vibration. There is at least one positive and at least one negative sensing electrode (S11+, S11−, S21+, S21−) on each resonator mass (1, 2) for detecting an out-of-plane output movement of the masses (1, 2). A detection circuit is connected to be said positive and negative sensing electrodes and determines the output signal by differential detection of the signals on the basis of the following formula: Sx_out=({S21+}−M{S11+})−({S21−}−M{S11−}), wherein {S21+}, {S21−} sensing electrode signals of the positive and negative detection electrode of the second mass, respectively; {S11+}, {S11−} sensing electrode signals of the positive and negative detection electrode of the first mass, respectively, μ=compensation factor.

The invention discloses a rotational inertia measuring method including the steps of 1), rotationally mounting an object on two fulcrums 2), providing auxiliary supporting to the object by springs; 3), applying force to the object and then releasing the force to enable the object to do torsional vibration; 4), acquiring the natural frequency of the object; 5), setting additional standard mass blocks in sequence and then repeating the step 3) and the step 4) after each setting so as to acquire data; 6), performing linear regression analysis to the data to acquire the rotational inertia of the object. The invention further discloses a rotational inertial measuring device comprising the additional standard mass blocks, a vibration sensor, a data acquisition system and a supporting mechanism, wherein the data acquisition system is connected with the vibration sensor, and the supporting mechanism is used for supporting the object. As the object is rotationally mounted on the two fulcrums to do torsional vibration, the rotational inertia of the object can be acquired rapidly and accurately by means of existing vibration measurement process and the regression analysis. In addition, the object can be of non-symmetrical structure; the rotational inertia measuring method and the rotational inertia measuring device have wide application range.

A small-sized rotational vibration testing apparatus having a wide band of measuring frequencies and capable of directly driving a rotary table (1) to oscillate or vibrate in a rotational direction under the action of torque generated by a vibration applying mechanism. The rotary table (1) is rotatably mounted on a base (2), and a plurality of coil frames (14) each having a coil (13) attached thereto are mounted on a flange (1c) of the rotary table (1) at an equal circumferential pitch or interval about its axis of rotation. A plurality of magnetic circuits (12) are fixedly secured to the base (2) in such a manner that the center of each coil (13) is positioned at the center of an associated magnetic circuit (12).

The disclosure describes an absorption spectroscopy method for sensing hydrogen gas in a sample atmosphere and an associated hydrogen sensor. A light beam, having a wavelength corresponding to a vibrational transition of hydrogen molecules from a ground vibration state to any excited rotational vibration state via a quadrupole interaction, is introduced into an optical cavity adapted to receive a sample atmosphere to be tested for the presence of hydrogen gas. The light is introduced into the cavity in an off-axis alignment to systematically eliminate cavity resonances, while preserving the absorption signal amplifying properties of such cavities. Hydrogen absorption is measured is terms of cavity output, as in the ICOS technique.

A disk drive and a method for operating the disk drive compensates for rotational vibration (RV) by adaptively modifying the gains of two separate linear vibration sensors so the sensor gains are optimal under any given condition. The two sensors provide two signals S1, S2, respectively, to the disk drive's servo control processor that generates the control signal to the voice coil motor (VCM) actuator that controls the positioning of the read/write head. The processor uses S1, S2 and the head position error signal (PES) as inputs to run an adaptive RV feedforward (RVFF) algorithm. The adaptive RVFF algorithm takes the PES and sensor outputs S1 and S2 as inputs, mathematically determines the required correction to the sensor gain factors k1 and k2, respectively, and then adjusts the gain factors k1 and k2 accordingly. Each signal S1, S2 is then modified by its adjusted gain factor k1, k2, respectively. The difference in the modified S1, S2 signals is the RVFF signal that is summed with the control signal to generate the RV-compensated control signal to the VCM actuator.

One or more layers of constrained layer damping material is strategically placed within a data storage library having one or more sources of rotational vibration energy. Data storage devices, such as disk drives, are isolated from each other and from a drive tray by a first layer of constrained layer damping material. The drive trays are isolated from drive enclosure bays by a second layer of constrained layer damping material. A third layer of constrained layer damping material isolates each drive enclosure bay from the housing of the data storage library. The net effect is a significant reduction of the amount of rotational vibration energy arriving at each data storage device from other system components, such as a blower module. Additionally, the amount of rotational vibration energy arriving at each data storage device from other data storage devices is also reduced. By mounting the data storage devices to the drive trays in a single plane, the rigidity and mass of the drive tray is increased, reducing its susceptibility to external rotational vibration energy.

Higher-precision measurement is achieved by an optical inner surface measuring device configured to cause a probe to enter into the inner peripheral surface or deep hole of a target object, capture and observe reflection light from the inner surface in a three-dimensional manner, and measure the accuracy of the target object. In a structure including an optical fiber built into a tube, a light path conversion unit arranged at a leading end side of the optical fiber, and a motor configured to rotationally drive the light path conversion unit, a unit for measuring the amount of runout of a rotation shaft unit of the motor is provided. Shape data on the inner peripheral surface of a target object is obtained by calculating at a computer reflection light from the target object, and is modified by displacement amount data from a displacement measurement unit to realize high-precision measurement with no measurement error resulting from runout and rotational vibration of the rotation shaft of the motor.

A disk drive (HDD) subject to linear and rotational vibration, includes an independent sensing unit for sensing a rotational velocity component of the HDD rotational vibration in a predetermined frequency range.