57 results about "Rigid model" patented technology

The invention discloses a parametric modeling method of a rigid-flexible coupled model. The method includes the steps of 1, establishing a rigid component model, 2, establishing an APDL macro file of a flexible body model, 3, establishing a rigid-flexible coupled system parametric graphical user interface, 4, inputting flexible body parameters in the interface and reading, altering and updating the APDL macro file, 5, executing the updated APDL macro file to build the flexible body model, 6, inputting rigid body model parameters, reconstructing a rigid body model, importing a flexible body modal neutral file and generating a command file containing a rigid-flexible coupled dynamics simulation model, 7, importing the command file, loading a virtual prototype model, conducting dynamics simulation analysis and outputting a simulation result and 8, outputting the optimum simulation data and storing a data file according to the simulation result. According to the rigid-flexible coupled model parametric modeling method, automatic creation of the parametric modeling of a flexible body and the rigid-flexible coupled model can be achieved, manual intervention is not needed in the whole process, the problem that it is difficult to parameterize the flexible body in the engineering practice is solved, the modeling efficiency is improved, and the method has very good engineering application value.

A method and apparatus for determining acquisition geometry of an imaging system from a set of calibration matrices for an arbitrary position of the system, a projection matrix makes a point in a 2D image correspond to a point of an object in a space. This matrix is produced for any unspecified position of the system from knowledge of a limited number of pre-computed calibration matrices. For instance, a projection matrix may be computed by interpolating coefficients of calibration matrices and/or applying a transformation with a rigid model defined comprehensively or locally to a particular calibration matrix.

A three-dimensional wind-resistant design method for a power transmission tower includes the steps: carrying out a rigid model balance force measurement wind tunnel test by means of increasing and decreasing components of cross arms, and measuring shape coefficients of a power transmission tower body with the overlong cross arms and all direction wind angles of the cross arms; and obtaining wind load cross-power spectrums, based on a base response force spectrum, of a downwind direction, an across-wind direction and a reversing direction of each node by means of a height sectioning estimation method of power transmission tower node wind load spectrums, and obtaining three-dimensional equivalent node wind load directly used for power transmission tower wind-resistant design by the aid of a load-response correlation method based on the node wind load cross-power spectrums. The three-dimensional wind-resistant design method for the power transmission tower takes the influence of different wind direction angles on the shape coefficients into consideration, truly measures shape coefficient values of the overlong cross arms serving as special components, breaks through normative limitations, and takes full account of characteristics of the power transmission tower with the overlong cross arms, wind induced response of the power transmission tower in the downwind direction is calculated, and simultaneously wind induced response of the power transmission tower in the across-wind direction and the reversing direction is calculated, so that safety, economy and reliability in design of the power transmission tower with the overlong cross arms are guaranteed.

A design method of an aeroelastic model for a long-span transmission tower-line system is disclosed. On the basis of boundary layer wind tunnel test data of a rigid model, a finite element model is utilized to calculate that relaxed Froude number similarity criterion of transmission towers, the influence of the elastic stiffness of a transmission line and two kinds of variable proportion transmission line models upon wind-induced response is changed, an aeroelastic model with long span is designed. The influence of material nonlinearity and gradient wind height of concrete filled steel tube onwind-induced response is further analyzed by the finite element model. The method has the advantages that the aeroelastic model of long span can be reasonably designed by increasing the elastic stiffness of the transmission line and adopting an accurate line length similarity ratio; consideration of the material nonlinearity of concrete-filled steel tubes has little effect on wind-induced response at design wind speed, and the wind-induced response decreases when considering the gradient wind height.

The invention discloses a swing aeroelastic model and a shock-test wind tunnel test method thereby and belongs to the technical field of structural wind-resistant design and test for building engineering. The swing aeroelastic model comprises a high-rise building rigid model, a rigid support rod and a support. The high-rise building rigid model is disposed at the upper end of the rigid support rod which is disposed vertically and is located above the support. The swing aeroelastic model further comprises a torsional vibration layer, an X-axial vibration layer and a Y-axial vibration layer, which are horizontally disposed on the support. The rigid support rod is connected with and penetrates through the vibration layers. The shock-test wind tunnel test method by the swing aeroelastic model includes the steps of firstly, setting the swing aeroelastic model; secondly, respectively regulating rigidity of springs and mass of mass blocks in the torsional vibration layer, the X-axial vibration layer and the Y-axial vibration layer according to test requirements so as to meet the test requirements; and thirdly, setting the swing aeroelastic model meeting the test requirements in a wind field, and performing wind tunnel test. Axial vibrations are not coupled, and more accurate test results can be obtained.

The invention discloses an elastic correction method of an airplane lifting resistance aerodynamic characteristics, which is characterized by comprising the following steps of: step 1, obtaining lifting force of a rigid wing; step 2, obtaining a lifting force correction formula; step 3, obtaining the resistance of the rigid wing; step 4, obtaining a resistance correction formula; and step 5, obtaining a correction parameter according to wings of different airplanes, and correcting the lifting force and the resistance of an airplane. According to the elastic correction method, the provided correction formulas are simple and clear to express by taking that the lifting force correction formula and the resistance correction formula of the airplane are finally provided as an aim, so that the elastic correction method is suitable for the airplane with a large span-chord ratio wing to carry out numerical value pneumatic calculation on a rigid model and elastic correction on lifting force and resistance properties characteristics after a wind tunnel test, and has higher correction precision on the airplane with the large span-chord ratio wing.

The invention discloses a vibrating table testing method suitable for rock and soil slopes and a model box, and belongs to the field of experimental equipment. The vibrating table testing method comprises the following steps: determining the type of a to-be-tested model slope, and assembling the model box according to the type; building a slope die body corresponding to the type by utilizing the assembled model box; standing the built slope die body in the model box for 1 to 2 days; installing the model box with the slope die body by utilizing a vibrating table, and loading a corresponding seismic waveform. The model box is formed by assembling a base, an enclosure structure, a trapezoidal framework, horizontal stiffening ribs, a longitudinal stiffening rib, a hollow square pipe and a wall body. According to the model box disclosed by the invention, the functions of a laminar shear model box and a rigid model box can be respectively realized by regulating the tightness of the hollow square pipe arranged at the rear side of the model box, the model box can be respectively applied to vibrating table testing of soil and rock slopes, the side wall body is transparent, the slope die body can be conveniently manufactured, the damage situation of a test can be observed, and meanwhile, the model box has the characteristics that disassembling and assembling can be freely carried out, and the operation is flexible.

The invention discloses a helicopter rotor airframe coupling system model and application thereof, which are used for analyzing the dynamic stability judgment of articulated, hingeless and bearingless rotor helicopter systems and belong to the technical field of the design of a helicopter. In the invention, an equivalent paddle rigid model with an equivalent hinge overhanging beam or a 15-degree-of-freedom beam element model is used as a rotor paddle; a rigid model with the pitching and rolling degrees of freedom or a 15-degree-of-freedom beam element model is used as an airframe structure; and the aerodynamic force of the section of the paddle is calculated by utilizing the lifting line theory. A paddle motion equation, an airframe motion equation and an aerodynamic force model equation are subjected to simultaneous processing to form a motion equation set so as to obtain a motion equation of a helicopter rotor airframe coupling system; and the motion equation is solved to obtain the dynamic stability of the helicopter system. The helicopter rotor airframe coupling system model disclosed by the invention has higher reliability; and the dynamic stability of the helicopter system can be accurately analyzed by adopting a time domain analysis method.

The invention relates to a multi-rigid-block-body multistage multi-position extension-retraction deformation physical simulation experiment method, which comprises the following steps of obtaining thestratum information and construction condition of a research region; clearly defining the existing construction distribution features of a substrate; performing systematic interpretation on the faultby using earthquake data; analyzing the geometrical and kinematics features of the fault according to the fault fine interpretation results; judging the current stage stress field direction; compiling a construction development history balance profile; clearly defining the fault activity stage number and the intensity; designing an experiment model at equal proportion by determining the proportion of the practical region and the experiment model; determining the shape and the placement features of a rigid model according to the substrate fracture form and features; selecting proper experimentmaterials; determining the material laying thicknesses; loading an experiment power device; performing staged deformation; laying an experiment material; and recording experiment process data and experiment results to obtain the experiment conclusion. The method provided by the invention is used for studying multistage deformation superimposed basin structures, and the simulation results are wellanastomotic with the practical deformation features.

The embodiment of the invention discloses an elastic gust response wind tunnel test device, which comprises wings, an adapter piece, a wing connecting piece and a test supporting piece, and is characterized in that the test supporting piece comprises a guide rail, supporting bases arranged at the two ends of the guide rail respectively, and a sliding assembly nested on the guide rail. The wings comprise a left wing and a right wing which are symmetrically arranged; the adapter piece comprises a left wing adapting piece and a right wing adapting piece; the left wing is arranged at one side of the wing connecting piece through the left wing adapting piece, and the right wing is arranged at the other side of the wing connecting piece through the right wing adapting piece, the wing connectingpieces and the adapting pieces are connected to the outer portion of the sliding assembly in a sleeving mode; and the wings are driven to move through sliding of the sliding assembly in the axial direction of the guide rail. According to the embodiment of the invention, the problems that an existing gust response model in a rigid model form cannot simulate the elasticity condition in a gust response test, the model support mode is single, and gust response tests under various boundary conditions cannot be met are solved.

The invention provides a large-amplitude vertical and torsional coupling free vibration test device for bridges in a natural wind field. The large-amplitude vertical and torsional coupling free vibration test device comprises a rigid model, lightweight high-strength strings, linear tension springs, a rigid bracket, spring protecting tubes, a turntable, a rigid stand column, a motor, gravity blocksand a rigid thin round rod. By utilizing the large-amplitude vertical and torsional coupling free vibration test device, a bridge rigidity model free vibration test can be effectively conducted in the natural wind field without large wind tunnel equipment, and the size of a test model is not limited by the size of a wind tunnel, thus a large-scale model test can be realized. Compared with the traditional wind tunnel testing method, the large-amplitude vertical and torsional coupling free vibration test device can greatly reduce the geometric nonlinearity in the case of large amplitude vibrations, can solve the problem of excessive blocking rate in the large amplitude vibration wind tunnel test, thereby being suitable for studying large amplitude vibrations; and by utilizing the turntable,the wind deflection angle of the model can be adjusted very easily, further the wind resistance of the bridges at different wind deflection angles can be studied comprehensively and conveniently, andthe large-amplitude vertical and torsional coupling free vibration test device is more convenient than the traditional wind tunnel test.

The invention discloses a blocked analysis method for a large-size machine tool structural member. The method comprises the steps of establishing a combining surface rigid model based on a three-dimensional fractal contact theory, and identifying a normal stiffness and lateral stiffness; performing parameter modeling of the large-size structural member (crossbeam) based on a definite element method, and integrating the identified normal stiffness and the lateral stiffness into a large-size structural member three-dimensional model; and utilizing a parameter blocked designing method and a particle swarm optimization method, optimizing the dynamic performance of the large-size structural member (crossbeam), and designing the optimized large-size structural member (crossbeam) three-dimensional model by means of an optimization result. A re-manufacturing factor is taken into a designing period so that the structural member not only can satisfy function and performance requirement of a product and furthermore facilitates manufacturing, transportation, assembling and re-manufacturing. The blocked analysis method for the large-size machine tool structural member is deeply understood, thereby better guiding designing and application of the large-size machine tool structural member.

The invention provides an image feature matching method and system based on local linear migration and rigid model. Correct matching is established by removing wrong matching from initial matched dot pairs. The method comprises: a model corresponding to geometric transformation between to-be-matched images is established for rigid geometric transformation between the to-be-matched images, a model corresponding to posterior probability with matched dot pairs in a correct matching mode is established, and model parameters are resolved and obtained based on a nearest neighbor matching dot, a least square method, and an optimization method; and the posterior probability with initial matched dot pairs in a correct matching mode is calculated and correctness of the initial matched dot pairs is determined according to a threshold value. According to the method, model establishment is carried out under the circumstance that rigid transformation exists between the to-be-matched images, so that the matching error rate is substantially reduced; and even when lots of wrong matching exits in initial matching, the good robustness is still kept.

An experimental setup for bridge deck large-amplitude vertical-torsional coupled free vibration in wind tunnel test, which belongs to the technical field of wind tunnel test apparatus. The experimental setup includes the rigid model, the rigid circular rods, the lightweight rigid circular sprockets, the chains, the linear tensile vertical springs, the bearings, the sliders, and the guides. For the new setup, large-amplitude vertical-torsional coupled free vibration of a rigid deck model that failed in conventional testing device can be adapted by the vertical deformation of the springs without any lateral tilt. As a result, the possible nonlinear mechanical stiffness due to the springs tilt in conventional testing device is excluded. In addition, owing to the low rolling friction and damping between the sprockets and the chains, the mechanical damping ratio of the system are quite low and stable for very large-amplitude vibrations.

The invention relates to a pseudo-static anti-seismic test device and method for a long tunnel structure. The pseudo-static anti-seismic test device comprises a counter-force structure, a loading structure and a cubic rigid model box, the counter-force structure comprises a counter-force pedestal and a counter-force wall, and the counter-force wall is of an L-shaped structure and is annularly arranged around the counter-force pedestal; a cubic rigid model box is placed on the surface of the counter-force pedestal, and a surrounding rock similar material for test simulation and a long tunnel structure model are placed in the cubic rigid model box; the loading structure comprises four hydraulic actuators which are vertically arranged, the upper actuator is connected with the second layer of the model box, the lower actuator is connected with the first layer of the model box, and the inertia force distribution mode of the structure is simulated through different applied forces during loading; according to the invention, the size effect influence caused by a vibration table reduced scale model can be reduced, large-scale tunnel structure model test analysis is realized, the earthquake action is simulated through force-displacement hybrid control, and the earthquake dynamic response of a long and large tunnel is better simulated.

The invention discloses an adaptive sparse coding fusion non-rigid three-dimensional model classification algorithm with a wide application range, and the algorithm comprises the steps: firstly extracting the average geodesic line features, thermonuclear features and shape diameter function features of a non-rigid model, so as to construct complementary multi-feature shape description; secondly, generating feature vectors of AGD-BoF, HKS-BoF and SDF-BoF through a bag-of-features model, creating three feature dictionaries through random samples, and generating a heterogeneous multi-feature weight matrix through training; and finally, realizing effective classification of the non-rigid model by using a Sotfmax classification algorithm through adaptive fusion of the feature weight matrix andsparse optimization coding. The method is higher in recognition accuracy, is higher in robustness, and is wide in application range.

The present invention relates to a method for manufacturing a crossbeam for a heddle frame of a loom allowing to make, at low cost and without waste, a lightweight and very rigid crossbeam, whose heddle-support rod is positioned on the support section in an accurate position that is completely linear, controlled and capable of being reproduced. This manufacturing method is characterized in that one uses a rigid model that has at least one rectilinear groove having a width substantially equal to that of the heddle-support rod; one positions the non-rigid heddle-support rod in the groove to make it rectilinear; one lays a glue line on the junction zone; one positions a rigid support section that is not necessarily rectilinear in a predetermined manner on the model and on the heddle-support rod by flattening the glue line, and one maintains the support section and the heddle-support rod integral with the model, at least while the glue is setting.

An embodiment of the invention discloses a rigid memory substitution simplification special effect processing system, a rigid memory substitution simplification special effect processing method, equipment and a computer software program product. The rigid memory substitution simplification special effect processing method includes acquiring topological structures of preset rigid models; dividing the rigid models into a plurality of rigid fragment models on the basis of the topological structures; simplifying the rigid fragment models on the basis of center-of-mass coordinates; simulating simplified rigid fragment model data by the aid of solvers. According to the technical scheme, the rigid memory substitution simplification special effect processing system, the rigid memory substitution simplification special effect processing method, the equipment and the computer software program product in the embodiment of the invention have the advantages that the models are differentiated on thebasis of the topological structures for the problems of high memory and hardware resource consumption, long manufacturing time and high cost when the complicated three-dimensional models are processed in traditional modes, partial fragment model point-surface data are transformed into point data, accordingly, thousands of amounts of computation can be exponentially reduced, the solution performance can be optimized, resource occupation can be reduced, and the time and the cost can be saved.

The invention discloses a dynamic constraint combined human body inertia parameter identification method. The human body is simplified into a multi-segment rigid model composed of multiple segments ofrigid bodies, and a dynamic equation of the multi-segment rigid model is established; and human body motion sampling data is collected via a motion capturing system and a ground counterforce detection system, a first-step identification human body inertia parameter is obtained via a first simplified mechanical equation, a second-step identification human body inertia parameter is obtained by introducing a basic physical constraint, and a third-step identification human body inertia parameter is obtained via a second simplified mechanical equation, and finally, the inertia parameter whose second-order norm is minimal is selected as a human body inertia parameter identification optimization result. Multiple constraints are introduced, so that a calculation process of human body inertia parameter identification is clear and can be programmed easily; the dynamic equation is simplified to measure the joint moment directly, a joint moment estimated value constraint is introduced for optimization, and the accuracy of an inertia parameter identification result is improved.