1020 results about "Differentiator" patented technology

A method and system for achieving stability while reallocating resources in a logically partitioned environment. The present invention comprises Performance Enhancement Program (PEP), Classification Program (CP), System Analysis Program (SAP), and System Evaluation Program (SEP). PEP allows a user to enter several performance parameters. CP classifies each of the virtual systems in the managed system based on their workload. SAP analyses the managed system to determine the configuration of the managed system. Managed systems configurations are classified according to the reciprocity of resource allocation and the overall symmetry of the managed systems. SEP evaluates the configuration of the managed system and recommends alterations for improved performance of the managed system. The managed system will be optimized when the functional differentiator (FD) of the virtual systems is small enough to allow reallocation of resources without an unacceptable sacrifice in managed system stability.

A high-frequency power supply system includes an anomaly detector 3 which detects an anomaly occurring in a circuit on the side of a load L as from an outputting end A of a high-frequency power source 1. The anomaly detector 3 includes a first detector 21 which detects a voltage value Vf of a high-frequency forward wave, a second detector 22 which detects a voltage value Vr of a high-frequency reflected wave, a reflection coefficient calculator 23 and a differentiator 24 which calculate a reflection coefficient differential value dΓ/dt from the forward wave voltage value Vf and the reflected wave voltage value Vr, and an anomaly determiner 25 which determines of an occurrence of an anomaly based on the reflection coefficient differential value dΓ/dt. When the anomaly detector 3 outputs an anomaly detection signal to the high-frequency power source 1, high-frequency power source 1 stops its power output operation.

A transporter that includes a platform for supporting a load and at least one primary ground-contacting element. The transporter includes an actuator for applying torque to the at least one primary ground-contacting element for propelling the transporter with respect to a surface. The transporter also includes a controller for controlling the actuator, the controller includes an input for receiving specification by a user of a desired direction of travel based on a position of a member with respect to a fiducial axis, a differentiator for calculating a rate of change of the position of the member with respect to the fiducial axis, and a processor for generating a yaw command signal based at least on the position of the member and the rate of change of the position of the member which is weighted based on the level of experience of the user.

This invention introduces an oral-dental anatomy modeling method and an implant treatment planning system based on a full anatomy model (FAM). Dental Implant Treatment Planning systems place implants on 2D slices of DICOM files, and sometimes on 3D models of bones and remaining teeth. Because the final look and feel of implants and restorations depend on how well they go along with the remaining teeth and soft tissues, treatment planning without tissue model presents safety and aesthetics risks. A FAM consists of models for bones, teeth, soft tissues and nerves. They are created from CT and optical scans, and assembled together with model registration techniques. The tissue model is the real differentiator. A treatment planning system uses FAM as a unique reference throughout the workflow. Its implant placement, restoration preview and surgical guide design are all based on FAM.

The invention relates to a PMSM servo system control method based on fuzzy and active disturbance rejection control. A position signal is given by a differential tracker to arrange a transition process so that the contradiction between rapidness and overshoot of a system is solved, and uncertainty, friction torques and external disturbance due to modeling errors of the system are observed via an expansion state observer; according to the error between the differentials generated by the differential tracker and state variation generated by the expansion state observer, a fuzzy inference rule is obtained with application of experimental experience of technical staff, so that a fuzzy rule control table of an error proportion coefficient, a differential coefficient and an integration coefficient is established; accurate control amount is obtained after de-fuzzification, so that parameter self-adaptive adjustment of a nonlinear error feedback control law is realized; and compensation amounts of the nonlinear error feedback control law and the expansion state observer to the total disturbance forms the control amount, thereby realizing optimal control for an controlled object. The method of the invention improves both tracking precision and disturbance rejection capability of the system.

A method and a language processing and knowledge building system (LPKBS) for processing textual data, receives textual data and a language object; segments the textual data into sentences and each sentence into words; generates a list of one or more natural language phrase objects (NLPOs) for each word by identifying vocabulary classes and vocabulary class features for each word based on vocabulary class feature differentiators; creates sentence phrase lists, each including a combination of one NLPO selected per word from each list of NLPOs; groups two or more NLPOs in each sentence phrase list based on word to word association rules, the vocabulary classes, the vocabulary class features, and a position of each NLPO; replaces each such group of NLPOs with a consolidated NLPO; maps each segmented sentence to a sentence type; identifies a semantic item for each mapped NLPO; and identifies and stores associated attributes and relations.

The invention discloses a method and a device for controlling speed of a permanent-magnet synchronous motor. The method includes that an active-disturbance-rejection control technology is adopted for a speed ring, speed setting and a speed detection value are taken as input of a first-order active-disturbance-rejection controller, a tracking differentiator reasonably arranges a transition process, an extended state observer observes an actual value of rotating speed of the motor, estimates total disturbance of a system and acquires output of the speed ring through a nonlinear state error feedback control ratio, a load torque observer is designed through detection values of a current and the speed, and observed load torque through output of a feedforward controller and the active-disturbance-rejection controller is taken as reference input of a quadrature-axis current. The method carries forward characteristics of overshoot freeness, high disturbance rejection capacity, good robustness and the like of the permanent-magnet synchronous motor in speed control in the active-disturbance-rejection control technology, and compensation is performed on the problem of load disturbance, so that the problem of fluctuation of the rotating speed under the circumstance of load disturbance is improved.

The invention relates to a quadrotor unmanned plane control method based on a fuzzy expansion state observer and an adaptive sliding formwork. The method comprises steps that a quadrotor unmanned plane system model is established, and a system state and controller parameters are initiated; a tracking differentiator is designed; a non-linear expansion state observer is designed; fuzzy rules are established; a parameter adaptive law is designed; an adaptive sliding formwork controller is designed. According to the method, the expansion state observer is designed to estimate indetermination of a system model and external disturbance; a pole assignment method is utilized to determine an initial value of an expansion state observer parameter; the fuzzy rules are introduced to realize online setting for the expansion state observer parameter; the parameter adaptive law is designed to acquire ideal controller gain; the adaptive sliding formwork controller is designed, rapid stabilization of a system tracking error and convergence to a zero point are guaranteed, and rapid and stable position tracking and pose adjustment of the quadrotor unmanned plane are realized. The method is advantaged in that system performance is improved, and rapid and stable system position tracking and pose adjustment are realized.

In a coaxial two-wheeled vehicle, an attitude controller (84) calculates motor torque Tgyr for maintaining a base so that it has a target angle from deviation between base angle command θref serving as attitude command and current base angle θ₀ calculated by using a gyro sensor (13) and an acceleration sensor (14). On the other hand, at a position proportional controller (86R), a differentiator (88R) and a velocity proportional controller (89R), there is performed PD control with respect to deviation between rotation position command Prefr of a motor rotor (92R) for right wheel and current rotation position θr of a motor rotor (92R). A current control amplifier (91R) generates motor current on the basis of added value of motor torque which is the control result and estimated load torque T₁ calculated by using pressure sensors to drive the motor rotor (92R).

The invention relates to a flexible satellite locus linearization attitude control method based on a disturbance observer. The invention aims at solving problems that a single locus linearization control method is poor in capability of inhibiting interference, is poorer in robustness, and does not consider external interference and the impact from flexible accessories. The method comprises the steps: employing Euler angles for describing attitudes of a spacecraft, employing an idea of equivalent disturbance, and building a flexible spacecraft dynamics and kinetics equation; solving the pseudo-inverse of a controlled object under the condition of neglecting equivalent disturbance, designing a quasi-differentiator of a specific type, and obtaining the nominal control of an expected locus; and designing a linear time varying adjuster through proportion-integration control. The method gives consideration to the influence of equivalent disturbance, designs the disturbance observer, and guarantees the asymptotic convergence of a tracking error of a flexible spacecraft. The method improves the anti-interference capability of a system, and improves the robustness of the system. The method is used in the attitude control field of flexible satellites.

The invention discloses a structure and a design method of an improved active-disturbance-rejection position controller for a direct current (DC) motor; the DC motor is taken as a controlled object, and an output position signal is taken as a controlled variable; the controller mainly consists of four parts, i.e., a tracking differentiator, a nonlinear state error feedback part, an extended state observer and a disturbance compensation part. The improved active-disturbance-rejection position controller is mainly used to improve a fal function in a nonlinear function in the extended state observer, and the fal function is used to determine the tracking performance of the extended state observer and the controller; the concrete improvement measure is adding a linear feedback area into non-linear feedback; therefore, the problem that in the traditional method, timely control cannot be realized when the system error is too large and the gain is too low can be solved on the basis of guaranteeing system stability. By comparing simulation lines obtained before and after the improvement for the controller, the structure and the design method which are provided by the invention are proved to accelerate the output signal response speed under the condition that the position error of the DC motor is larger, thus improving the integral control performance of a system.

A hybrid method for dental implant treatment planning and a corresponding approach to make a surgical guide. After digital treatment planning is performed with CT scan data, a master model is created, which embodies the patient anatomy and entire treatment plan. Jaw bone, tooth surfaces, soft tissues and nerves are all contained by the master model. The plan details including implant sizes and positions, surgical guide drill options, as well as the choice of a surgical kit, are all conveyed by the master model. Meanwhile, models of specially designed “implant inserts (or replicas)” are also generated, which have one end that fits into the implant holes on the master model and another end to make the surgical guide. The master model and inserts are manufactured with rapid prototyping technology. A surgical guide is later on made from them with conventional lab processes. A main characteristic of this approach is that the master model and the inserts are the physical embodiment of a virtual treatment plan. With them, the surgeons can continue the treatment planning for operations like tooth extractions and bone modifications before making the surgical guides. Therefore the treatment planning workflow is a combination of digital treatment planning and a physical model based planning, in other words, a hybrid approach. A differentiator in this invention is the generation of a closed solid model of the soft tissue, as part of the master model, from the scan data. This approach can be applied to create both bone-borne and tissue-borne surgical guides with low cost process, which is a big advantage over other approaches.

A system and method is disclosed that provides a digital self-adjusting power supply for semiconductor digital circuits. The power supply provides a substantially constant minimum supply voltage with regard to process corner, junction temperature, external voltage source, load variation, and operating frequency. The system comprises a slack time detector, a voltage adjuster, and a digital pulse width modulation (PWM) modulator. The system supplies a minimum required voltage without the used of a band gap or reference voltage. A finite state machine is also used to minimize oscillations introduced by start-up, load transients, frequency changes, and the like, thereby eliminating the need for a proportional integrator differentiator (PID) circuit.

Pre-distortion, whose magnitude—and preferably phase—are frequency-dependent, is applied to an input signal in order to reduce spurious emissions resulting from subsequent amplification of the signal. In preferred embodiments, the pre-distortion technique of the present invention is implemented in combination with the (frequency-independent) magnitude and phase pre-distortion technique described in U.S. patent application Ser. No. 09/395,490 (“the '490 application”), where the frequency-dependent pre-distortion corresponds to amplifier distortion that has a magnitude that is proportional to the frequency offset from the carrier frequency and a phase shift of ±90° on either side of the carrier frequency. Since these characteristics match those of a differentiator, a thorough correction of this part of the amplifier's distortion can be achieved using a differentiating filter. Embodiments of the present invention may be implemented in the baseband domain. Implementations may also be based on look-up tables that are adaptively updated to ensure optimal performance over time.

A tri-rotor attitude control method based on an auto-disturbance rejection controller (ADRC) includes determining a mathematic model of a tri-rotor aircraft, determining input-output variables suitable for the model, tracking differentiator design, building an expansion state observer, and selecting a non-linear error feedback rate. A core control panel based on Atmega 2560 serves as an execution module, the motor is powered through a drive circuit, and the PWM wave can be adjusted according to the rotating speed of the motor. An inertial navigation module is formed by a tri-shaft gyroscope sensor, an accelerometer, a GPS and a digital compass, and a power supply module provides appropriate voltage to power each module through a power distribution module. For a tri-rotor aircraft model, parameters of all modules are adjusted to achieve excellent effects for auto-disturbance rejection control method. Module design and parameter adjustment of all modules allow three rotors to retain an excellent flying state through an auto-disturbance rejection control system.

The invention relates to an active-disturbance-rejection trajectory linearization control method suitable for hypersonic velocity maneuvering flight. The active-disturbance-rejection trajectory linearization control method regards a part different from a nominal model as a general disturbance, establishes a hypersonic aircraft attitude and angular velocity dynamic model with multi-source complex uncertainty and strict feedback form, designs attitude ring and angular velocity ring model auxiliary expansion state observers, adopts a non-linear tracking differentiator to arrange a transition process for a given guidance command and generate a nominal command of an attitude ring, designs an active-disturbance-rejection trajectory linearization attitude ring controller containing a feedforward tracking control law, a feedback stabilization control and a disturbance compensation term, and designs an active-disturbance-rejection trajectory linearization angular velocity ring controller containing a feedforward tracking control law, a feedback stabilization control and a disturbance compensation term. The active-disturbance-rejection trajectory linearization control method achieves high-precision anti-disturbance control under the given conditions of large-margin guidance command and control constraint, and has high adaptability for multi-source disturbance large-scale perturbation in hypersonic velocity long-span maneuvering flight.

A demodulation circuit for an Amplitude Shift Keyed (ASK) modulated signal includes an envelope detector, an alternating voltage amplifier, a differentiator circuit, and a comparator having a hysteresis connected in series. The envelope detector produces an envelope signal from the received ASK signal. The amplifier blocks the DC component of the envelope signal and amplifies AC components of the envelope signal to obtain a steeper slope of the rising and falling edges. The differentiator circuit then processes the transition edges to provide a differentiated signal having positive and negative electrical pulses. The comparator converts the pulses into a binary data stream which corresponds to the transmitted data stream. The combination of the differentiated signal and comparator having a hysteresis enables better stability and sensitivity of the ASK demodulation circuit.

The invention discloses an airplane angular rate signal reconstruction method based on unscented kalman filter. The method comprises the following steps of: (1), denoising an attitude angle measurement signal containing measurement noise through a nonlinear tracking differentiator to obtain a differential signal of an attitude angle, and constructing a virtual measurement equation; (2), constructing a state equation of a system on the basis of natural characteristics of an airplane and according to tri-axial angular rate signals and torque characteristics of the airplane; and (3), reconstructing an angular rate signal of the system by selecting the unscented kalman filter technology as the processing manner because both the state equation and the measurement equation are nonlinear and the estimation precision can be influenced by traditional operation for linearizing a nonlinear equation.