1355 results about "Constant velocity" patented technology

A method is disclosed for determining fundamental-frequency repeatable runout (1FRRO) coefficients in a disk drive. The disk drive includes a transducer head, a rotating magnetic disk having a plurality of concentric data tracks defined by embedded servo wedges that provide position information, and an actuator coupled to the head. In the method, the head is caused to move in a substantially constant velocity motion across a selected portion of the tracks of the rotating magnetic disk in response to a control signal. The position information is read from the embedded servo wedges as the head moves across of the selected portion of the tracks. The 1FRRO coefficients are determined based on the position information read as the head moved in a substantially constant velocity motion across the selected portion of the tracks.

The invention relates to mobile tracking of vehicle targets in the communication and transportation field. A self-adapting interactive multiple model mobile target tracking method comprises the following steps of establishing mixed initialized input. including a covariance matrix of a mixed initial condition and a mixed initial state. of each model; establishing constant velocity (CV) and constant acceleration (CA) motion models; updating: calculating covariance matrix and innovation of an error according to a Kalman filter formulation; constructing a likelihood function of a target motion module by utilizing the innovation of a Kalman filter result, and calculating a Markov state transition probability matrix; carrying out estimation output after being fused by utilizing the Markov state transition probability matrix as weight of switch among each motion model. According to the self-adapting interacting multiple model mobile target tracking method disclosed by the invention, the problem that the error is increased or the tracking is failed caused by non-matching of a filter model and a target motion model due to the motion of a target in the traditional interactive multiple model algorithm is solved; the self-adapting interacting multiple model mobile target tracking method has the advantages of low calculation complexity and good tracking effect, and can be applied to target tracking of motor vehicles in the communication and transportation field.

A boot arrangement is provided for use with a constant velocity joint and shaft assembly including a shaft, a first joint part slidably engageable with the shaft, and a second joint part cooperable with the first joint part to transmit torque therebetween. The boot arrangement includes a sleeve adapted to slidably engage the shaft and having first and second ends. The second end of the sleeve is adapted to be connected to the first joint part. The arrangement further includes a boot having a first end adapted to be connected to the sleeve proximate the first end of the sleeve, and a second end adapted to be operatively connected to the second joint part.

A propeller shaft assembly (10) comprising a constant velocity universal joint (12) including a hollow shaft (20) and a connecting shaft (18) is provided. The hollow shaft (20) includes an aft open area (34) and is connected to an outer joint part (23) that has outer ball tracks (32). The connecting shaft (18) is connected to an inner joint part (25) that has inner ball tracks (46). A ball cage (26) that has a plurality of balls (28) is included. A standard plunge (22) that has an aft plunge portion (54) is also included. The aft plunge portion (54) and the aft open area (34) having inner diameters that are greater then or equal to an inner diameter D.sub.1 of the outer joint part (23). A first stop (55) limits the ball movement of travel in the aft direction. The first stop (55) is forcibly dispensable such that the connecting shaft (18) may release the first stop (55) and intrude significantly within the aft open area (34) which is outside a normal operating range (24).

A spherical inner surface 5 of the outer race 1 and track grooves in the outer race 1 are each defined by a post-hardening cut surface. A spherical outer surface 6 of the inner race 2 and track grooves in the inner race 2 are also each defined by a post-hardening cut surface. A retainer 4 has a spherical outer surface 10, a spherical inner surface 11 and inner surfaces of the pockets 9, all of which are defined by a post-hardening cut surface. Respective surfaces of the retainer 4, the outer race 1 and the inner race 2 which contact with each other are formed with a surface treatment layer for reducing a frictional resistance.

Embodiments of the systems and methods disclosed herein utilize a brushless DC motor (BLDCM) to drive a single-stage or a multi-stage pump in a pumping system for real time, smooth motion, and extremely precise and repeatable position control over fluid movements and dispense amounts, useful in semiconductor manufacturing. The BLDCM may employ a position sensor for real time position feedback to a processor executing a custom field-oriented control scheme. Embodiments of the invention can reduce heat generation without undesirably compromising the precise position control of the dispense pump by increasing and decreasing, via a custom control scheme, the operating frequency of the BLDCM according to the criticality of the underlying function(s). The control scheme can run the BLDCM at very low speeds while maintaining a constant velocity, which enables the pumping system to operate in a wide range of speeds with minimal variation, substantially increasing dispense performance and operation capabilities.

The hydraulic linear actuator system of the present invention includes a pump that is configured to rotate in a single direction at a substantially constant velocity. Both the direction and flow rate of fluid through the system is controlled by adjusting the positional relationship between the stator and the rotor of the pump. This positional relationship is adjustable between a forward flow state, a non-flow state and a reverse flow state. The hydraulic linear actuator is responsive to the flow of fluid through the system so as to be displaced in a first direction by the forward flow state of the pump and in a second direction by the reverse flow state of the pump.

A system and method for improving installation of a prosthesis, particularly an acetabular cup. The system and method may include implementation of a constant velocity relative motion between a prosthesis and an installation site. For example, an installation system may be fixed relative to the installation site, with the prosthesis fixed into an initial position. The prosthesis is moved at constant speed (i.e., with minimal if any acceleration or applied impulses) relative to the installation site. That is, one or both of the prosthesis or the installation site may be in motion. Resistive forces to installation of a prosthesis may thus be reduced by maintaining the prosthesis constantly in motion relative to the installation site. Securing a processing/implanting tool directly to the installation site may offer advantages.

A mud pump is provided with two cylinders for pumping mud in connection with water well drilling, and two sets of hydraulic oil cylinders with pistons connected to and driving the pistons of the mud pump by piston rod connecting plates. A flow divider located downstream from a hydraulic oil power supply pump applies hydraulic power evenly to two sets of mud pump driving cylinders, but the flow divider accommodates re-routing of hydraulic oil to one driving cylinder during a directional valve shift for the other driving cylinder. Rod position sensing switches coupled to an electro-hydraulic control system coordinates the action of the sets of pump driving cylinders and thereby of the mud pumping cylinders, to control and phase the mud driving pistons produce a steady mud pump output simulating the effect of constant velocity pistons.

To increase inspection throughput, the field of view of an infrared camera can be moved over the sample at a constant velocity. Throughout this moving, a modulation can be provided to the sample and infrared images can be captured using the infrared camera. Moving the field of view, providing the modulation, and capturing the infrared images can be synchronized. The infrared images can be filtered to generate the time delay lock-in thermography, thereby providing defect identification. This filtering can account for the number of pixels of the infrared camera in a scanning direction. For the case of optical modulation, a dark field region can be provided for the field of view throughout the moving, thereby providing an improved signal-to-noise ratio during filtering. Localized defects can be repaired by a laser integrated into the detection system or marked by ink for later repair in the production line.

A system and method for obtaining biometric imagery such as iris imagery from large capture volumes is disclosed wherein a substantially rotationally symmetric mirror such as a cone or sphere is rotated at a constant velocity about a central axis.

A method is disclosed for enhancing estimation of parameters for an aircraft simulator having a simulation model and covariance matrix. According to embodiments of the invention the method comprising providing a first estimation of predetermined parameters of the aircraft's maneuvers performance, performing maneuvers with the aircraft, collecting actual flight data over a time representing the maneuvers of the aircraft, dividing the actual flight data into segments with quasi-constant velocity, feeding recorded flight control data of each segment into the simulation model, comparing output from the simulation model with actual flight data to determine an error vector and updating the covariance matrix and the estimation of the desired parameters using the error vector.

The invention relates to a test table for a five-function test of a driving shaft assembly of a constant velocity universal joint. The test table comprises a rack, a fixing end and a slippage end, wherein the fixing end and the slippage end are located on the rack; the fixing end comprises a guide rail and a sliding block, a swinging bedplate, a linear displacement driving assembly, a sliding bedplate, a torque rotating speed sensor, a spindle supporting base, a spindle, a clamp, a swinging and driving assembly, a spindle driving assembly, a linear displacement sensor and the like; the slippage end comprises a swinging bedplate, a clamp, a rotating shaft, a supporting base, a pull pressure sensor, a rear sliding board, a front sliding board, a guide rail and a sliding block, a swinging and driving assembly, a linear displacement sensor and the like; and the rack comprises a guide rail and a sliding block, a linear displacement sensor, a linear displacement driving assembly and the like. With regard to the driving shaft assemblies of the constant velocity universal joint with the different structures and sizes of the working pieces, the test table can test working pieces with various specifications and structures by replacing the clamps, and adjusting the position of the clamp at the fixing end and the position of the clamp at the slippage end, and the size of a rotary center distance.

The invention provides a secondary surveillance radar track extraction method for multimode polling and S-mold roll-calling interrogation. By using the method, false targets under an interference environment can be effectively removed and the accuracy and the real-time performance of the S-mode query are improved. The method is realized through the technical scheme that plot combination is conducted to S-mode plot data which is searched from the same sector of a secondary surveillance radar interrogator, the mean value and the variance of the plot data are calculated, and a real track is initiated after time-space registration; the combined plot data is divided according to the sector characteristic of radar and an associated sector window is created to enter a plot and track processing flow; firstly de-biased measurement conversion is conducted to the associated plot data, a CV (Constant Velocity) model, a CA (Constant Acceleration) model and a current statistical model are combined into a target multi-model, and the interactive input state estimation vector and the variance of each filter under an interactive effect are calculated; interference targets are removed by adopting interference target removing strategies; and unnecessary target files are removed through track management, tracking is ended and a correct target track extraction result of the secondary surveillance radar is given.

The invention discloses a rigid-body mode integration test method for an automobile power assembly and a suspension system. By adopting a constant-velocity amplitude sinusoidal scanning excitation signal as an excitation source of a four-channel vibration table, the method not only can test the translation rigid body modes along X, Y and Z directions and the rotation rigid body modes around the X, Y and Z directions of the power assembly relatively well, but also can test the homonymous jump mode and incongruous jump mode of the suspension system relatively well.