34results about How to "Reduced dynamic performance" patented technology

A positioning device for positioning an object table relative to a reference frame with a drive unit including a first part connectable to the reference frame and a second part for holding the object table is described. The drive unit is constructed to displace the object table in a first direction by generating a force in the first direction on the second part, and a torque acting on the second part about an axis substantially perpendicular to the first direction such that the resulting force of the force and the torque is directed substantially through the center of gravity of the assembly including the object table and the second part.

The invention discloses a feedforward decoupling control method based on a three-phase two-arm tri-level active power quality compensator. For the purpose of realizing reactive compensation, negative sequence compensation and harmonic compensation, one two-input and two-output coupling system is decoupled into two independent single-input single-output systems, thus quickly tracking current and improving reliability of the system; and a corresponding PWM (pulse width modulation) method is adopted to drive a switching tube to acquire an expected current. The feedforward decoupling deadbeat control method based on the three-phase two-arm tri-level active power quality compensator can be used to realize complete compensation and inhibition of the negative sequence and harmonic waves of the systems.

An apparatus for power demand distribution in a fuel cell vehicle includes: a battery management system calculating an allowable battery power that a battery can supply; a power demand distribution controller configured to derive a vehicle demand power including a drive motor demand power required by the drive motor, and determine a value corresponding to a vehicle demand power minus the allowable battery power being scaled down or the drive motor demand power, as a fuel cell demand output; and a fuel cell controller configured to drive the air compressor feeding the air to the fuel cell to enable a fuel cell to generate the fuel cell demand output calculated by the power demand distribution controller.

A two-dimensional force feedback type electro-hydraulic servo valve based on two freedom degrees of a valve element comprises an inclined wing type torque motor and a hydraulic amplifying mechanism. An armature of the inclined wing type torque motor is composed of a horizontally-arranged center shaft and two side wing faces, the two side wing faces and the left pole shoe surfaces and the right pole shoe surfaces of an upper yoke and a lower yoke represent the 180-degree array characteristic with a vertical axis as a center axis, the two side wing faces are inserted between the pole shoe surfaces of the upper yoke and the lower yoke in parallel, and four work air gaps identical in height are formed. The inclined wing type torque motor is connected to one end of a valve body, and the center axis of the armature and the center axis of the valve element are located on the same straight line.

The invention discloses an analog-digital converter circuit adopting the partial multiplex technique of a multistage amplifier. The analog-digital converter consists of a flash structure and at least one combination flow stage. The flash structure is taken as the last stage of the flow stages, and the combination flow stage comprises a first flow stage and a second flow stage, wherein, the first flow stage consists of a first stage sub-amplifier A1, a second stage sub-amplifier A2, and a third stage sub-amplifier A3 in series sequentially; the second flow stage consists of a second stage sub-amplifier A2, a third stage sub-amplifier A3, and a fourth stage sub-amplifier A4 in series sequentially; and the second stage sub-amplifier A2 and the third stage sub-amplifier A3 are shared by the first flow stage and the second flow stage. By adopting the analog-digital converter circuit, the consumption of an amplifier and a system thereof is cut, and the design complexity and the dynamic performance are reduced.

The invention discloses an indoor positioning and navigation method based on BIM and computer vision technologies. The method comprises steps of generating an indoor navigation network path based on aBIM (Building Information Model), setting a customized attribute of an internal space entity of a building to generate an IFC file, and analyzing and extracting a geometric space component and the topological relation thereof through the IFC file to generate a geometric topological network model; achieving indoor positioning based on the computer vision technology, carrying out preliminary positioning through an image recognition method, and then achieving positioning calculation by applying a projection imaging principle in combination with the preset prior information; connecting a positioning point with the geometric topology network model, obtaining a user interest point, and generating a shortest path. The method is advantaged in that low-cost, dynamic and visual indoor positioning navigation can be realized.

The invention aims to provide a vector control asynchronous motor speed adjusting method combining pole changing with frequency changing and provides a pole-changing asynchronous motor speed adjusting system which comprises a pole-changing asynchronous motor, a frequency-changing power source, a pole-changing control circuit and a control system. The frequency-changing power source powers the pole-changing asynchronous motor through the pole-changing control circuit which is controlled by the control system, the control system actually measures rotating speed of the pole-changing asynchronous motor, and a connecting mode of stator windings of the pole-changing asynchronous motor is YY / Y connection. When voltage of the motor increases to a rated value along with frequency (the rated value corresponds to rotating speed (i)n( / i)> / =(i)n( / i)1N), a pole-changing operation is performed on the pole-changing asynchronous motor, and reconstruction (i)U( / i) / (i)f( / i) is performed according to new motor parameters after pole changing and current rotating speed to enable a constant-torque speed adjusting range of a system to be expanded under new parameter conditions, so that the objective of expanding a constant-torque speed adjusting range of the motor without increasing voltage of the power source and number of inversion circuit semiconductor switch devices is achieved.

The invention relates to a method for machining identical workpieces (14) by means of a numerically controlled workpiece machining device (10), comprising the following steps: machining a workpiece (14) by prescribing a target tool path (34) for a tool (12) of the workpiece machining device (10); controlling a working distance (22) of the tool (12) from the workpiece (14) at a defined target distance such that the tool (12) is displaced along the target tool path (34) on a distance-controlled actual tool path (36) when machining the workpiece; optimizing the target tool path (34) for a further workpiece (14) using the distance-controlled actual tool path (36) of the machined workpiece (14) and machining the further workpiece (14) as prescribed by the optimized target tool path (34'); and / or evaluating a workpiece quality of the machined workpiece (14) using the distance-controlled target tool path (36).

The invention relates to an air bearing, in particular to a pressure-sharing cavity air thrust bearing which comprises at least one air floatation sliding block; a supporting surface of each air floatation sliding block is provided with at least one pyramid pressure-sharing cavity; the supporting surface is opposite to a substrate; the conical bottom surface of the pyramid pressure-sharing cavityis flush with the supporting surface; the peak of the pyramid pressure-sharing cavity is provided with an orifice; the orifice is communicated with an air supply pipeline which is arranged in the airfloatation sliding block; and the air supply pipeline is communicated with an external pressurizing air source. According to the invention, a diverging pyramid pressure-sharing cavity is adopted so that the high-pressure air more easily flows out along a parallel streamline when the high-pressure air flows in a bearing clearance through the orifice, the bearing vibration phenomenon educed by vortex close to the orifice is restrained, and the harm of micro vibration on the static and dynamic performance of the whole moving system is reduced.

The invention discloses a heat-resistant and aging-resistant chloroprene rubber tube. The chloroprene rubber tube comprises chloroprene rubber, chlorinated butyl rubber, poly-octene rubber, polyisoprene rubber, polyether urethane, zinc oxide, bis(2,4-dichlorobenzoyl) peroxide, 2,5-dimethyl-2,5-di(tert-butylperoxy) hexane, stearic acid, nano calcium carbonate, hollow glass microspheres, nano montmorillonite, basic sodium and aluminum carbonate, a silane coupling agent, an anti-aging agent DFC-34, an anti-aging agent A, dipentaerythritol diphosphite, hexaphenoxy cyclotriphosphazene, vinyl silicone oil, an accelerant, zinc diricinoleate, aluminum dihydrogen phosphate and 1,3-bis(citraconimidomethyl)benzene. The heat-resistant and aging-resistant chloroprene rubber tube has high strength, good heat resistance and aging resistance and excellent storage stability, and products of the chloroprene rubber tube can meet use requirements in various fields and have long service life.

The invention discloses a high-precision array analog-to-digital convertor applicable to a CMOS image sensor, and belongs to the technical field of design of analog circuits. The high-precision array analog-to-digital convertor comprises a sampling holding circuit, a comparator, a digital-to-analog convertor, a successive approximation register and a digital error correction circuit; a full differential structure is adopted in the analog-to-digital convertor; input signals are output to a capacitor array top plate through the sampling holding circuit, and simultaneously, input into the input end of the comparator; the output end of the comparator is connected with the successive approximation register; and the successive approximation register controls and stores a capacitor array according to a comparator result, and outputs the capacitor array to the digital error correction circuit, so that finally binary output is obtained. By means of the high-precision array analog-to-digital convertor disclosed by the invention, the capacitor array is divided into three sections of capacitor arrays, wherein each section of capacitor array is designed by adoption of a non-binary redundant capacitor architecture; the high-precision array analog-to-digital convertor has a certain tolerance for comparative errors due to incomplete establishment of circuits, jitter and noise of reference voltage and the metastable state of a dynamic comparator; the dynamic comparator is also adopted; quiescent current does not exist; and thus, the power consumption of the whole circuit is effectively reduced.

The invention discloses a current ripple compensation circuit and method adopting a wide bandgap device and a silicon-based device, and belongs to the technical field of power electronics. The methodcomprises the following steps: a silicon-based device is taken as a power main circuit of a switching tube to realize high-power conversion; a wide bandgap device is used as a compensation branch of the switching tube to realize current ripple compensation; the high-power converter main circuit works in a low-frequency state; the current ripple compensation branch works in a high-frequency state;the power main circuit and the compensation branch circuit are connected in parallel. And the high-frequency compensation branch compensates the current ripple of the low-frequency main circuit, and the error between the voltage feedback value and the reference value passes through the voltage controller Gvc to obtain a reference current value Iref. The compensation circuit achieves the compensation of the high-frequency branch for the current ripples of the low-frequency branch while giving play to the advantages of a silicon-based device and a wide bandgap device, and reduces the total costand the conduction loss of a switching tube.

The present invention provides a cam curve design method based on the k-order harmonic function, and belongs to the technical field of cam design, in order to solve the problem that the mechanism is fluctuate and cannot be applicable to the high speed occasion due to that some characteristic parameter curves among the existing harmonic cam curves are close to infinity at the end point. The methodcomprises: obtaining key point data determined by the cam for realizing the function; making the key point data to be dimensionless to obtain the dimensionless time T and the dimensionless displacement S; writing a cam curve fitting program to obtain a first cam curve expression based on the k-order harmonic function, and adding the first cam curve expression to a local control point; and after the solution, transforming the first cam curve expression to obtain a second cam curve expression, combining the first two expressions to obtain a final cam curve expression, determining the order of k,adding the final cam curve expression to the local control point, and obtaining an optimized cam curve. The method provided by the present invention is used in the design of cam curves.

The invention relates to an access method for 5G system. The method shares on the user side the ID by the soft SIM card, and the user device can dynamically modify the ID number of the SIM card; all user devices sharing the ID will have the same ID, and then access the network based on the non-orthogonal multiple access unlicensed transmission scheme; while on the network side, the method reducesthe signaling burden of control side of the user access network through the unlicensed orthogonal access mode, and allocates the same data bearer to all user devices of the same ID on the core networkside at the same time; and when a large number of devices access at the same time, the signaling load burden of the access network and the core network control side can be effectively reduced, the resource utilization efficiency in the network device can be improved, and the user can normally access for data transmission.

The invention discloses a harmonic current suppression method and device of a flexible direct current converter and a storage medium. The harmonic current suppression method of the flexible direct current converter comprises the steps of obtaining the number of harmonic waves to be suppressed and the amplitude and phase of background harmonic waves in power grid voltage; performing phase delay on the background harmonic waves to generate a harmonic wave adjusting quantity; connecting a harmonic wave trap in series with a current inner loop control output end of the flexible direct current converter to obtain a modulation wave processed by the harmonic wave trap; and superposing the harmonic wave adjusting quantity on the modulation wave processed by the harmonic wave trap so as to suppress the harmonic current of the flexible direct current converter. According to the embodiment of the invention, an original control ring structure does not need to be changed, the calculation amount is small, and the harmonic current can be suppressed under the condition that the influence on the dynamic performance and the steady-state characteristic of the flexible direct-current converter is reduced.

In a method for shifting the point of machining (112) of a work piece where machining is being done to the work piece by a tool (108) of a machine tool (100, 300), a. the tool (108) is moved using at least one tool axis; b. the tool (110) is moved using a work piece axis during work piece machining such that the point of machining (112) comes to a work space (yeff xeff) of the tool (108) and / or the point of machining (112) comes to an area near the machine body; wherein c. a more dynamic movement is carried out by the tool axis(es) than by the work piece axis.

The invention discloses a supercompact combined navigation positioning system and method. The supercompact combined navigation positioning system comprises a master controller, a coprocessor, a communication module, a display screen module, an INS measurement unit, a satellite RF signal processor and a high-accuracy antenna, wherein the master controller is used for building a combined navigationfilter and giving out a command, the coprocessor is used for building a vector tracing ring circuit, acquiring and processing GNSS data and transmitting the GNSS data to the master controller, the INSmeasurement unit is used for responding the command given out from the master controller and acquiring data of a gyro, an accelerometer and a dip angle sensor which are arranged in advance, the satellite RF signal processor is used for acquiring a satellite signal and then transmitting the satellite signal to the coprocessor after amplification, filtering and frequency conversion, and the communication module is used for achieving data communication between the master controller and a management center. INS and GNSS information are highly fused by a supercompact combination mode, the cohesiveness and the interference-resistant capability of the combined navigation system are improved, so that the positioning accuracy is further improved.

The invention belongs to the technical field of machine designing and manufacturing and particularly relates to a parallel type macro-micro high-precision movement platform. The parallel type macro-micro high-precision movement platform is characterized in that a first linear driving system and a second linear driving system are parallel to each other and are symmetrically fixed to the front side and the rear side of the plane of a base (1) respectively; a terminal platform (2) is in a Y shape, and the three top ends of the terminal platform are connected with one ends of three identical branched chains respectively; the other end of the first branched chain and the other end of the second branched chain are hinged to a first linear feeding platform (17); the other end of the third branched chain is hinged to a second linear feeding platform (35); the two linear feeding platforms are connected with linear guide rails of the systems of the two linear feeding platforms respectively through guide rail sliding blocks; linear grating rulers are parallel to the linear guide rails; a plane grating (54) is fixedly installed on the base (1); flexible hinge units are embedded into the branches chains; a pressure sensor is fixedly installed at the tail end of a piezoelectric ceramic actuator. According to the parallel type macro-micro high-precision movement platform, a flexible unit design mode of input decoupling is adopted, and the parallel type macro-micro high-precision movement platform has the characteristics of being high in movement precision and high in resolution ratio.

The invention is directed to a suction device for suction and transport of yarn (1) for a service robot for a yarn manufacturing textile machine. The suction device comprises a suction tube (0), provided with a front opening (02) and a rear opening (01) that are fluidically interconnected with each other by an inner conduit (03). A suction mouth (00) is arranged at the front opening (02) and a first vacuum ejector (3) is fluidically connected to the inner conduit (03). The first vacuum ejector (3) is adapted to generate a pressure gradient between the suction mouth (00) and the rear opening (01) for conveying an air flow through the suction mouth (00) via the suction conduit (000) to the inner conduit (03). At least one yarn twist retaining element (9) is arranged in the inner conduit (03) between the suction mouth (00) and the first vacuum ejector (3).

The invention relates to a half-bearing, a material, a device and a method for a steel backing / carbon fiber knitted fabric self-lubricating lining. According to the invention, the half-bearing for the steel backing lining is made by arranging a polymer self-lubricating composite material lining (1) reinforced by a layer of knit carbon fiber on the inner surface of the steel backing (2); the half-bearing lining material adopts epoxy resin as substrate and carbon fiber knitted fabric as a reinforced body, short carbon fiber is added as a secondary reinforced body, and various modification, filling and self-lubricating ingredients are added. Carbon fiber knitted fabric is used as the reinforced body for the half-bearing to increase the shear strength, the impact strength and the compression strength of the lining material; the advantages of high bearing capacity, good impact resistance, low friction coefficient, good dynamic performance and wear resistance are obtained; the mold pressing forming technology is simplified, and the operation difficulty is reduced; steel is used to replace copper to save expensive metal; lead is not used, so that the environment is protected; the inner surface of the half-bearing is made through net shape forming, so that the geometric dimension is high in stability; the recycling and reusing are convenient.

The invention relates to an access method in a 5G system. On the user side, a soft SIM card is used to share an ID, and the user equipment can dynamically modify the ID number of the SIM card. All user equipment sharing the ID will have the same ID, and then based on The non-orthogonal multiple access authorization-free transmission scheme accesses the network; on the network side, through the authorization-free orthogonal access method, the signaling burden on the control plane of the user access network is reduced, and at the same time, on the core network side, all users with the same ID The user equipment is assigned the same data bearer; when a large number of equipment are connected at the same time, it can effectively reduce the signaling load burden on the control plane of the access network and the core network, improve the resource utilization efficiency of the network equipment, and ensure the normal access of users for data transmission .

A two-degree-of-freedom motion decoupling flexible hinge mechanism, the mechanism includes a flexible hinge base and a drive branch, wherein the flexible hinge base includes a flexible hinge branch and a rigid connector, and the rigid connector includes a terminal located in the middle part of the flexible hinge base The rigid output platform and the upper, lower, left, and right rigid platforms respectively located on the upper, lower, left, and right parts of the flexible hinge base; the upper, lower, left, and right rigid platforms respectively pass through the flexible hinge branch chain and the terminal rigid output platform connected, and the upper, lower, left, and right rigid platforms are respectively connected to the rigid base of the flexible hinge base through flexible hinge branches. The two-degree-of-freedom motion decoupling flexible hinge mechanism of the present invention can realize the decoupling between the terminal's all-directional motion and force, thereby helping to improve the motion accuracy of the two-degree-of-freedom motion decoupling flexible hinge mechanism.

The invention discloses a high-precision array analog-to-digital converter applied to a CMOS image sensor, which belongs to the technical field of analog circuit design and includes a sample-and-hold circuit, a comparator, a digital-to-analog converter, a successive approximation register, and a digital error correction circuit; The analog-to-digital converter described above adopts a fully differential structure. The input signal is output to the top board of the capacitor array through a sample-and-hold circuit and connected to the input terminal of the comparator. The output terminal of the comparator is connected to the successive approximation register. The successive approximation register controls the capacitor array according to the result of the comparator And store it, and output it to the digital error correction circuit to get the final binary output. In the present invention, the capacitor array is divided into three capacitor arrays, wherein each capacitor array adopts a non-binary redundant capacitor architecture design, and the incomplete establishment of the circuit, the jitter and noise of the reference voltage and the metastable state of the dynamic comparator are caused There is a degree of tolerance for comparison errors. A dynamic comparator is also used without quiescent current, which effectively reduces the power consumption of the overall circuit.

The invention discloses a feed-forward decoupling control method of a three-phase two-arm three-level active power quality compensator. In order to realize reactive power, negative sequence and harmonic compensation, a two-input and two-output coupling The system is decoupled into two independent single-input and single-output systems to realize fast tracking of the current and improve the reliability of the system, and then drive the switching tube to obtain the desired current by using the corresponding PWM modulation method. The feed-forward decoupling deadbeat control method of the three-phase two-arm three-level active power quality compensator can realize the complete compensation and suppression of the system negative sequence and harmonics.

The invention relates to an air bearing, in particular to a pressure-sharing cavity air thrust bearing which comprises at least one air floatation sliding block; a supporting surface of each air floatation sliding block is provided with at least one pyramid pressure-sharing cavity; the supporting surface is opposite to a substrate; the conical bottom surface of the pyramid pressure-sharing cavityis flush with the supporting surface; the peak of the pyramid pressure-sharing cavity is provided with an orifice; the orifice is communicated with an air supply pipeline which is arranged in the airfloatation sliding block; and the air supply pipeline is communicated with an external pressurizing air source. According to the invention, a diverging pyramid pressure-sharing cavity is adopted so that the high-pressure air more easily flows out along a parallel streamline when the high-pressure air flows in a bearing clearance through the orifice, the bearing vibration phenomenon educed by vortex close to the orifice is restrained, and the harm of micro vibration on the static and dynamic performance of the whole moving system is reduced.

The invention relates to a method for controlling a multicylinder internal combustion engine. The cylinders are synchronised for adjusting the torques of the individual cylinders, said torques forming the total torque of the internal combustion engine. The cylinder synchronisation is checked for efficiency. At least one error signal that indicates a failure is generated when the cylinder synchronisation fails.

The invention discloses an analog-digital converter circuit adopting the partial multiplex technique of a multistage amplifier. The analog-digital converter consists of a flash structure and at least one combination flow stage. The flash structure is taken as the last stage of the flow stages, and the combination flow stage comprises a first flow stage and a second flow stage, wherein, the first flow stage consists of a first stage sub-amplifier A1, a second stage sub-amplifier A2, and a third stage sub-amplifier A3 in series sequentially; the second flow stage consists of a second stage sub-amplifier A2, a third stage sub-amplifier A3, and a fourth stage sub-amplifier A4 in series sequentially; and the second stage sub-amplifier A2 and the third stage sub-amplifier A3 are shared by the first flow stage and the second flow stage. By adopting the analog-digital converter circuit, the consumption of an amplifier and a system thereof is cut, and the design complexity and the dynamic performance are reduced.