43 results about "Virtual displacement" patented technology

A non-wearable Personal Emergency Response System (PERS) architecture is provided, implementing RF interferometry using synthetic aperture antenna arrays to derive ultra-wideband echo signals which are analyzed and then processed by a two-stage human state classifier and abnormal states pattern recognition. Systems and methods transmit ultra-wide band radio frequency signals at, and receive echo signals from, the environment, process the received echo signals to derive a spatial distribution of echo sources in the environment using spatial parameters of the at least one transmitting and / or receiving antennas, and estimate postures human(s) in the environment by analyzing the spatial distribution with respect to echo intensity. The antennas may be arranged in several linear baselines, implement virtual displacements, and may be set into multiple communicating sub-arrays. The decision process is carried out based on the instantaneous human state (local decision) followed by abnormal states patterns recognition (global decision).

A non-wearable Personal Emergency Response System (PERS) architecture is provided, implementing RF interferometry using synthetic aperture antenna arrays to derive ultra-wideband echo signals which are analyzed and then processed by a two-stage human state classifier and abnormal states pattern recognition. Systems and methods transmit ultra-wide band radio frequency signals at, and receive echo signals from, the environment, process the received echo signals to yield a range-bin-based slow signal that is spatially characterized over a plurality of spatial range bins, and estimate respiration parameter(s) of the human(s) by analyzing the slow signal. The antennas may be arranged in several linear baselines, implement virtual displacements, and may be set into multiple communicating sub-arrays. A classifier uses respiration and other derived features to classify the state of the human(s). A decision process is carried out based on the instantaneous human state (local decision) followed by abnormal states patterns recognition (global decision).

The invention provides an inverse problem design method of a pseudo S1 flow surface of an axial-flow compressor. The method comprises the steps of selecting an axial-flow compressor blade; calculatingcoordinates of upper and lower molded lines, and constructing the pseudo S1 flow surface to obtain flow field flow conditions and flow parameter distribution; obtaining a new load distribution curvethrough a parameterization method; calculating the virtual moving speed and the corresponding virtual displacement of an arc surface in the pseudo S1 flow surface; updating grid calculation domain boundaries and internal grid node coordinates; carrying out at least five pseudo S1 flow surface inverse problem designs with multiple design sections on the compressor blade; calculating the inverse problem to obtain the blade profile geometry of each design section meeting the target load; generating a new full-blade-height compressor blade geometry through geometric stacking; and verifying the aerodynamic performance of the new compressor blade through full three-dimensional viscous positive problem calculation. According to the inverse problem design method of the pseudo S1 flow surface of the axial-flow compressor, the load distribution of the pseudo S1 flow surface is given autonomously, the inverse problem modification design is carried out on the initial blade, and finally the new blade geometric configuration meeting the target load distribution is obtained.

The invention discloses a road surface riding quality identification method based on an inverse virtual excitation method. The road surface riding quality identification method comprises the steps ofestablishing a 1 / 2 vehicle 6-DOF system model, obtaining a frequency response function matrix [H(f)] of the system, and based on a matrix inverse transformation method, solving for a generalized inverse matrix [H(f)]+ of the frequency response function matrix of the system; obtaining an unsprung mass and centroid vertical acceleration of a front axle and an unsprung mass and centroid vertical acceleration of a rear axle, obtaining a vehicle body centroid vertical acceleration and a vehicle body pitch acceleration, and constructing a vertical displacement response vector {z-tilde(t)} of the system using a fast Fourier transform method; according to the generalized inverse matrix [H(f)]+ and the virtual displacement response vector {z-tilde(t)}, solving for an effective road surface virtualexcitation vector {qe-tilde(t)}, and according to a time domain transfer function H(f)qe~qr of tire containment characteristics, solving for an actual road surface virtual excitation vector {qr-tilde(t)}; and according to the actual road surface virtual excitation vector {qr-tilde(t)}, solving for an international roughness index (IRI) of the spatial frequency to further obtain the road surface riding quality index (RQI). The method is simple to operate and high in efficiency.

A control method for a speed servo system, comprising the following steps: Obtain the target speed of the current speed control iteration cycle, denoted as S1; calculate the virtual displacement in the current speed control iteration cycle according to the S1, and obtain the virtual displacement and the moment The controlled object feedbacks the position difference, and records the difference as A1; calculates the target current according to A1, and the target current acts on the controlled object after being processed; obtains the target speed of the next speed control iteration cycle, and records is S2; calculate the virtual displacement in the next speed control iteration cycle according to S2, obtain the difference between the virtual displacement and the feedback position of the controlled object at this moment, and record the difference as A2; calculate the target according to A2 Current, the target current acts on the controlled object after being processed. On the premise of ensuring the control accuracy, the response speed of the position control function is improved, and the dynamic performance of the position control function is improved.

The invention discloses a method for correcting influence of thermal current on the related measuring precision of a digital image. A circular identification point array before and after that influence of thermal current is stabilized is identified, a 3D-DIC algorithm is used to solve displacement of a test piece sprayed with speckled along directions x, y and z, a parameter matrix in which the influence of thermal current causes a virtual displacement field of circular identification points is used to correct the displacement along the directions x, y and z, and thus, a more accurate surfacedisplacement field of the tested piece under influence of the thermal current is obtained. According to the method, a measuring device is simple, realization is easy, use is convenient and effective,the relative cost is lower, the influence of the thermal current on system imaging is reduced effectively, and the influence of thermal current on related measurement precision of the digital image can be corrected effectively.

The invention discloses a cable buckling modeling method. The modeling method comprises the steps of performing node division on an original whole cable core wire according to a change property of a geometric shape; decomposing the cable core wire into small units; constructing a corresponding stiffness matrix; and establishing a balance relationship by adopting a virtual displacement principle. Any point P is obtained in the cable core wire, and a tiny parallelepiped is cut, wherein the edge lengths in x, y and z directions are dx, dy and dz respectively. Firstly, a straight line for connecting the centers of the front and back surfaces of the hexahedron is taken as a moment axis; a balance equation sigma Mee'=0 of moments is listed out; and two similar equations are obtained according to the rest of two balance equations sigma Fy=0 and sigma Fz=0. According to the modeling method, a buckling stress generated during excessive cutting of cable wire cores with different lengths based on ANSYS finite element software is simulated, an influence law of core wire length on casing stress is analyzed, a simulation result shows that the casing stress is remarkably reduced with increment of the cable wire core length, and a reasonable casing height is given. A theoretical basis is provided for reasonable design and installation of a cable terminal of a ring main unit.