Showing papers on "Angular displacement published in 1980"

A new method of measuring radio source parameters of a partially polarized distributed source from spacecraft observations

Abstract: An experimental system is analyzed which is designed to determine the angular and polarization properties of low frequency radio sources from measurements made on a spinning spacecraft. The system has been optimized to provide high accuracies for sources at high as well as low elevation angles. Theoretical expressions are derived for the response of this system to a partially polarized point source. Integrations are then carried out to get the system response to a uniform circular distributed source. Data processing techniques are derived so that computer simulations can be carried out to investigate the accuracy of this technique. It is shown that using 24 measurements of a partially polarized source (with Q = U = V = 0.5), taken in one spacecraft rotation, the resulting rms errors in angular position are less than one degree and the errors in determining the Stokes parameters are generally 1-10% for a wide range of source elevations.

Coordinate measurement and radar device using image scanner

Abstract: A system for measuring angles, including a lens or antenna for focusing the radiation from an object scene onto an image sensor which is shifted by a clock, thereby producing the real time imaging of the object scene wherein each element of the object scene is detected as a pulse, representing the element angular displacement from the lens, at the output of the image sensor. A system for measuring angles of objects relative to the centerline of a lens or antenna. A goniometer for measuring the bearing of objects. A system for measuring the vector speed of objects. A velocity meter for measuring the speed of objects. A system for tracking objects. A system for motion compensation. A search, track or track-while-scan detection system. Without the lens or antenna, a system for recording and reproducing halograms.

Triaxis laser alignment system and method

Abstract: A system and method of determining the angular displacement of one or more members is disclosed. A reference laser beam is diffracted, reflected and impacted upon a face of a display as a light pattern in which the pattern spacing is representative of a determinable angular displacement relative to a reference pattern.

Laser beam boresight system

Abstract: Boresighting of an outgoing first laser beam axis to an imaging sensor reference axis is described by aligning a second laser beam axis, which is in fixed relation to the first laser beam axis, to an electromagnetic source reference beam axis and detecting the angular displacement between the second laser beam and the reference beam axes. The sensor reference axis is in fixed relationship to the reference beam axis. Error signals are generated by the detector which are proportional to the angular displacement and are utilized to correct the angular displacement to align the second laser beam and the reference beam axes. When the first laser beam is boresighted to the sensor reference axis, the image of the reference beam source in the sensor display will represent the target object to which the outgoing first laser beam is directed.

Receiver and method for use with a four-arm spiral antenna

Abstract: A receiver for locating a source of RF radiation received by a four-arm spiral antenna having an angular measurement frame normal to the antenna axis, including a detection circuit for detecting signals received from each of the spiral arms in response to receipt of RF radiation by the antenna; a first comparison circuit for comparing signals detected from a first opposite pair of the spiral arms to produce a first signal that is proportional to a first function of the frequency of the received RF radiation and the angular displacement of the radiation source in the measurement frame; a second comparison circuit for comparing signals detected from the remaining opposite pair of the spiral arms to produce a second signal that is proportional to a second function of the frequency of the received RF radiation and the angular displacement of the radiation source in the measurement frame; and a processing circuit for processing the first and second signals to produce third and fourth signals that are proportional to the angular displacement and independent of the frequency of the received RF radiation.

Mechanized trowel for finishing concrete slabs

Abstract: A mechanized trowel including a center body of an elongated configuration supported for rotational displacement about its longitudinal axis and having a helical troweling blade extending along the surface thereof adapted to engage, spread and trowel a body of cement in its plastic state, a supporting rail extended in parallelism with the center body supporting the center body for linear displacement therealong, and a truck supporting the end of the rail for translational displacement about a further axis perpendicularly related to the longitudinal axis of the center body and passing through the end thereof opposite the truck, and reversible, electrically energizable motors connected in driving relation with the center body for imparting thereto rotational, linear and translational displacement.

Apparatus for detecting relative motion

Abstract: A linear or rotational displacement transducer of the reflective ortransmissivetype uses a CCD image array (61); or a linear array of photo-sensitive diodes as the detector. In one embodiment the CCD array is angled, with respect to the axis of relative motion, such that all but two of the m cells in the array span the width of a line pair element (62) in the encoding scale. In another embodiment optical means (65) are employed to image all but two of the m cells in the array onto the line pair element.

Process and apparatus for adjustment of the angular position of a part in rotational motion

Abstract: A method and apparatus for determining the angular position of a point in rotational motion which includes a disk coupled to rotate with the rotating part. The disk includes a plurality of alternating teeth and spaces located about its periphery. At least one of the teeth has been removed to form an absolute or reference mark. A transducer is located adjacent to the disk to produce an electrical signal representative of the passage of teeth and spaces past the transducer. The electrical signal is processed to produce one or more output signals representative of the instantaneous angular position of the rotating part. Accurate results are produced even when large variations in instantaneous speed of the rotating part occur.

Method and apparatus for the control of synchronous motors

Abstract: A method and apparatus of variable structure for controlling asynchronous motors. More particularly, methods and apparatus for control of flux, torque, angular acceleration, angular velocity, and/or angular position of the rotor of an asynchronous motor, supplied through a converter having switched elements.

Cam machine with acceleration control

Abstract: The invention provides apparatus and a method for use in machining cam profiles, and is suitable for use in grinding, milling, turning or otherwise forming cams. A workpiece, i.e. a cam blank, is rotated adjacent a machine tool (e.g. a grinding wheel) and is moved relative thereto laterally of its axis of rotation so that stock is removed from the workpiece to form a predetermined cam profile thereon. At the same time, the angular displacement of the workpiece relative to a datum is continuously monitored and the rotational speed of the workpiece is varied in dependence on its instantaneous angular displacement so that the stock can be removed at a substantially constant rate, preferably defined by a predetermined program corresponding to the particular cam profile to be machined on the workpiece.

Controlled positioning of a motor shaft

Abstract: A method for positioning the shaft of a motor which can be subject to a rotation force in either direction of rotation by application of drive current of a respective polarity, in order to bring the shaft to a target angular position by the action of a digital control and a position sensor associated with the motor shaft for emitting a displacement step signal in response to each movement of the the shaft through an incremental angle constituting a given fraction of one cycle of shaft rotation, which includes giving the displacement step signal the form of a signal cycle of sinus-like waveform in response to each incremental angle of shaft movement, deriving from the displacement step signal a shaft movement signal having a value represented by the sum of a component proportional to the displacement step signal and a component proportional to the time derivative thereof, and, after the motor shaft has reached a defined angular speed and at the moment when the shaft position is spaced from the target position by one-half of the incremental angle, initiating a control signal having a value which decreases with time, comparing the shaft movement signal with the control signal, and varying the polarity of motor drive current in dependence on the polarity of the comparison result.

Correction of random angular displacements of optical beams

Abstract: An analysis is made of the possibility of correction of random angular displacements of the energy center of gravity of an optical beam (traveling in a turbulent atmosphere) by tracking the random angular position of the center of gravity of the image of a reference beam. The reference beam may be provided by an auxiliary source or it may represent part of the reflected original beam. It is shown that variance of the residual random angular displacements of the center of gravity of a beam can be reduced, under certain conditions, to not more than 25% of the same variance in the absence of correction. In particular, it is found that the proposed correction method is sufficiently effective for apertures smaller than the external scale of the turbulence. The time constant of the loop for the compensation of random displacements should be less than the ratio of the initial beam size to the average wind velocity.

Tools for drilling, reaming and the like with simultaneous angular and linear oscillatory motions

Abstract: A dental contra-angle which supports a tool socket for combined motion consisting of two oscillatory movements simultaneously, one motion being a linear reciprocating motion parallel to the axis of rotation, and the other motion being an oscillatory motion around the axis of rotation. A tool receiving aperture opens through one end of the socket and extends along the axis toward the other end. A tool for treating a root canal, when installed in the socket, will be given a combined motion consisting simultaneously of a linear reciprocating motion in the axis of the root canal, and an angular oscillatory motion around the axis of the root canal. The resulting motion of such a tool is one of dipping with simultaneous partial rotation.

Method and apparatus for digitally analyzing dynamic unbalance of a rotating body

Abstract: Mechanical vibration of a rotating test body is translated into a periodic signal which represents a combined vector of the unbalance means of the rotating body and the mechanism that rotates it. The periodic signal is divided into two orthogonal vector components. The magnitude of the two vector components are converted into digital signals and applied to a computer. Unknown values of four constants are determined by a preliminary test having three successive stages. In the first and second stages the test body is rotated to register the digital signals; in the second state the angular position of the test body is displaced a predetermined amount with respect to its first stage position. In the third stage of the test, a trial dead weight of a known mass is mounted on the test body and rotated to register the digital signals. The computer operates on the registered digital signals to determine the four constants in accordance with a set of equations. After the preliminary test, the data registered in the first stage of the preliminary test is substituted into another set of equations using the four constants to determine the dynamic unblance mass and its angular location.

Target seeking device

Abstract: A target seeking device having a gyro rotor rotating about its axis with two degrees of freedom about a central point of rotation. The device includes a detector fixed with respect to the housing of the device, an optical system by which the field of view of the device is imaged in the plane of the detector, means for producing relative motion between the field of view image and the detector, a signal evaluating circuit, means for producing precession motion of the gyro rotor, and position sensors which respond to the angular position of the gyro rotor relative to the housing. A torquer is provided for receipt of scanning signals. The signals of the position sensors are applied to the torquer through a feedback loop. An evaluation circuit is provided for producing follow-up signals from the detector signals and the position sensor signals.

Mechanical-optoelectronic angle comparator for determination of the angular position of a weapon mounted by a combat vehicle relative to the line of sight

Abstract: A mechanical optoelectric angle comparator for determining the angular position relative to the line of sight of a weapon mounted on a combat vehicle having a sighting device including an objective mirror which pivots on a first axis that is parallel to the axis of rotation of the weapon, is provided with a mechanism for mechanically transmitting the angular position of the weapon.

An angular displacement transducer

Abstract: A miniature non-contacting displacement transducer i described, designed to measure the static and dynamic angular rotation of a shaft. The measurement techniques uses an infra-red light source, a specially constructed fibre-optic probe and a receiver. Amplitude measurements within a range of 0+or-180 degrees may be made for frequencies from 0 to 500 Hz. The transducer has continuous resolution, producing a voltage output related to instantaneous angular displacement.

Dynamically tuned gyroscopes

Abstract: Gyroscope apparatus includes a tubular rotor that is supported at opposite ends by bearings, such as a gas-lubricated bearing, for rotation about its axis. A gimbal ring encircles the rotor and is resiliently supported with the rotor, for angular displacement about an axis at right angles to the rotor axis, by a pair of flexure pivots located intermediate the ends of the rotor. An inertia ring is mounted concentrically with the gimbal ring by another pair of flexure pivots for angular displacement about an axis at right angles to the rotor axis and the axis of displacement of the gimbal ring. The major part of each flexure pivot is contained within the radial thickness of the gimbal ring. Displacement of the inertia ring is sensed by pick-offs the outputs of which are used to control the restoring torque applied by torquers located outwardly of the pick-offs.

Rotary actuator with selectable response characteristics

Abstract: A rotary actuator is disclosed useful in controlling throttle settings on internal combustion engines. The angular displacement of the actuator shaft (18) is a function of the current applied to the actuator. In the disclosed embodiment the relationship between current and angular displacement has three distinct regions: increasing displacement, linear displacement and decreasing displacement with respect to applied current. These regions are matched to the engine characteristics to produce a desired response from the engine. The actuator consists of a rotor (24) biased by a coil spring (40) to a first position and displaceable to a plurality of intermediate positions by magnetic actuation from pole pieces (32) associated with current carrying coils (30). The arrangement and configuration ofthe rotor and pole pieces produce the desired three region response characteristic.

Rotational speed governor

Abstract: An improved rotational speed governor characterized by a non-linear response to speed changes, includes a control arm, the angular position of which changes in response to the rotational speed of the governor, the control arm carrying a weight held to a fixed position with respect to the control arm at speeds less than a first predetermined speed and displaced from said control arm by centrifugal force at speeds greater than that predetermined speed to effect a non-linear pivotal displacement response to the control arm.

Device for automatic measurement for engagement pitch of the thread on screw-like work pieces

Abstract: The device for measuring the engagement lead of the thread of a screw-like work piece, such as a hob, for example, includes a spindle for rotating the work piece about an axis, a measuring slider movable transversely to the axis and terminated with a feeler which is in sliding contact with a flank of the thread of the work piece whereby the path of movement of the measuring slider is angularly adjustable, a sliding carriage supporting either the measuring slider or the work piece to impart a relative axial displacement therebetween, a tachometer generator coupled to the axially movable sliding carriage to generate a signal proportional to the speed of the axial displacement, a sinusoidal potentiometer mechanically coupled to the measuring slider and to an angle measuring and adjusting device to adjust the angular position corresponding to the base lead angle of the thread of the work piece, the output of the tachometer generator being connected via the sine potentiometer to the electromotor for dirving the measuring slider so that the transverse feed of the latter is proportional to its relative axial displacement whereby the deviations from the preset lead angle are continuously recorded.

A system for controlling the angular position of a rotary member.

Abstract: A gun turret (11) at a weapons station is controllable about an azimuth axis. A weapon (12) is carried in the turret and is controllable in the turret about an elevation axis. The moments of inertia of the turret and weapon about the azimuth axis and of the weapon about the elevation axis are relatively high, in order to reposition the turret (11) or weapon (12) automatically when displaced from a desired position by a spurious torque such as that produced upon recoil of the weapon (12), the system provides for elevation and azimuth control through elevation and azimuth drive trains having reflected drive train inertias which are at least two orders of magnitude smaller than the inertia of the turret and weapon about the azimuth axis and at least one order of magnitude smaller than the inertia of the weapon about the elevation axis. The system senses spurious torque by using a deflector (27, 28) to monitor the velocity of the turret (11) and weapon (12), integrates the velocity signals and feeds them back in superimposition on any command signal to control a drive (26, 26 min ) applied to the drive trains.

Thread-rolling tool

Abstract: A thread-rolling tool having a body provided with thread rollers uniformly disposed along the circumference thereof, the axes of the rollers being in angular position relative to the axis of rotation of the body and at an angle equal to the lead angle of the helical line of the thread being rolled. The body includes groove-forming rollers having a pitch equal to that of the thread rollers and being disposed at an angle relative to the axis of rotation of the body and at an angle relative to the latter. The top portions of the thread of the groove-forming roller being disposed with an axial displacement relative to the top portions of the thread of a preceding thread roller, when viewed in the projection on a plane normal to the axis of rotation of the body 1, the amount of said displacement being: (P/2)-(Pβ/360°) where P is a pitch of the thread being rolled. β is an angle between the axes of rotation of the groove-forming and preceding thread rollers if viewed in the projection on a plane normal to the axis of rotation of the body.

Compensating for multiple shaft angular velocity inequality - by using electronic pulse detectors passing torque signals to control unit producing difference signal

Abstract: A method of measuring and compensating revolution rate and angular position differences of two or more shafts is esp. for propeller drive shaft control of multiple screw ships. It enables regulation shaft revolution rates to the same value and compensation of mechanical oscillations simply and reliably. Electronic pulse detectors prod. measurement values which are fed to an electronic measurement and control device. The difference signal derived from the detector outputs is used to adjust the torque applied to the shafts for a given drive system power output by varying the propeller blade incidence angle. The torque may alternatively be controlled by varying the power supply generator power, the load of an electrical drive motor, the slip of an electrical slip coupling, or the effectiveness of an eddy current brake where fixed propellers are employed.

Estimation of cloud motion from satellite pictures

Abstract: Estimation of lateral and rotational cloud displacement from satellite images is introduced based on various degrees of image abstraction. By using the luminance information, the maximum of the inger product surface of two images serves as a lateral displacement estimator. The peak detectability can be improved by prefiltering with a non-causal inverse filter. If the luminance is fit to a bivariate normal distribution, cloud motion and rotation is estimated from tracing the ellipses of equal density. Finally, the contour of clouds is Fourier transformed. The resulting coefficients reveal information about lateral and rotational displacement as well as size changes.

Compact optical pulse generator for revolution rate monitoring - has reflectors performing reverse reflection at given angular positions

Abstract: An optical pulse generator for monitoring revolution rates of parts rotating about axes, esp. in confined spaces as in cassette tape recorders, is extremely compact. A reflector attached to the rotating part periodically reflects light from a source to a sensor as the part rotates. The light sensitive detector (8) has a reception axis parallel to the light source (7) transmission axis. The reflector element (9) is arranged and shaped so that it reflects light back parallel to the direction of incidence for a given angular position. This is achieved by using reflector elements of parabolic section in the plane contg. the incident and reflected light paths. Alternatively, the section is hyperbolic or circular, or two mutally perpendicular plane reflector surfaces per element may be used.

Optical scanner with variable scan line angle

Abstract: A photographic recorder includes an optical scanner unit positioned to scan transverse lines across a photographic film driven slowly in a linear direction. The optical scanner unit is mounted for angular displacement, so that the scan-line across the film can be set to any angle in a range of about ±45 degrees relative to a line at right angles to the direction of motion of the film.

Measuring unit for car frame corrector for automobile

Abstract: PURPOSE:To obtain a car frame measuring unit which can be processed with a computer, by imaging horizontal projective plane under measured car body, taking the position of measuring reference of car at design on it as coordinate, giving the projection material on the coordinate and measured reference position, and measuring the tilt angle with a sensor. CONSTITUTION:A projection plane angle bar with hole 3 and the projection plane scale 4 are provided to above and benath the car 1' supported horizontally. Further, a thread 5, and projection rod 6 are fitted between a magnet 7 with hole and the car 1' to measure the inclination of the thread 5 and rod 6, i.e., distortion of the car 1'. The angular displacement sensor is used for the measurement of inclination. This measuring value is input to the computer consisting of a transducer 11, input signal matching unit 12, A/D converter 14, calculator for correction processing amount 16, and printer 18. Thus, the corrected pressure can automatically be indicated from the amount of distortion and the result after the correction of the distortion can be printed out.

Measuring method for displacement of target mark

Abstract: PURPOSE:To make it possible to measure the dynamic displacement and dynamic angular displacement of the trage mark of a moving body under no influence of shading without setting a slice level, by using a pickup tube available for random deflection. CONSTITUTION:Mark M with a difference in lightness of 90 deg. on the mark center traveling together with a moving body is provided and a pickup tube available for random deflection such as an image detector tube is used to scan on a random position near the center of mark M in a circular shape. From respective mean values of rectification values of synchronism between a carrier superposed on horizontal and vertical polarization voltages and the alternating-current component of a video signal and between the secondary carrier of a frequency twice the carrier and the alternating current component of the video signal, a shift value between the center of a circular scan and the mark, namely, coordinate values and gradient are calculated. Consequently, attention is paid only upon the phase relation between the video signal and carrier, so that the measurement can be attained under no influence of shading without setting a sliced level.

Directionally variable vibration generator

Abstract: A vibration generator for a reversible vibratory feeder or similar device that requires a change in the direction of a generally linear vibratory drive force comprises at least a pair of contra-rotating shafts (6,7) carrying eccentric weights (9, 10) in which one of the weights (10) is journalled on its shaft (7) so that it may shift from one angular position relative to its shaft to another according to the direction of rotation of the shafts.