30 results about "Velocity equation" patented technology

The invention discloses a method for predicting carbonate formation pore pressure by using log information. The method for predicting the carbonate formation pore pressure by using the log information is based on the effective stress theorem; and by establishing a framework longitudinal wave velocity and pore fluid longitudinal wave velocity equation, a carbonate formation pore pressure equation is established, so that the carbonate formation pore pressure is detected according to the measured log information, scientific evidences are provided for determining safety drilling fluid density during drilling design, and carbonate formation underground complex accidents in the construction process are effectively prevented.

The invention relates to a flight icing numerical value simulation method of a helicopter rotor wing. The flight icing numerical value simulation method is mainly characterized by comprising the following steps that: a vorticity compensation force algorithm is added into a momentum equation and an energy equation in a single fluid model used for vortex movement used for simulating air-super cold water drop two-phase flows under a rotating coordinate system in rotor wing trail traces, and a centrifugal force and geostrophic force algorithm is added into a super cold water drop sliding velocity equation; a water film movement and icing model of the centrifugal force and the geostrophic force is considered; and the algorithms and the models are used for carrying out the flight icing numerical value simulation flow process of the helicopter rotor wing, wherein the model of single fluid two-phase flowing used for simulating the simulating air-super cold water drop movement is realized by a partial differential equation group for describing the movement of air and air-super cold water drop binary mixtures in a rotor wing tail trace flow field, and a two-phase flow slipping speed model. The condition that the quality and energy changes are generated in water films and ice layers because of the rotary movement of the rotor wing is considered in the model of the water film movement and icing process on the rotor wing surface, and the icing shape of the rotor wing surface is obtained.

The invention relates to a dynamic mesh numerical solution method based on a modified fluid motion equation, and belongs to the technical field of optimization methods. The method comprises the following steps: introducing an original non-linear convective term inside a concept deconstruction equation of convection speed into a speed equation on the basis of a classic cauchy equation of motion; deriving a linear modified fluid motion equation so as to establish a dynamic mesh numerical iteration solver special for the modified fluid motion equation under a finite volume discretization method. The linear characteristic of the dynamic mesh numerical iteration solver achieves obvious advantage on solving the problem of an internal flow field of a rotary machine, namely the speed item coefficient a of an equation to be solved does not participate in the cyclical iteration process of a PISO algorithm any longer, the equation can be solved by only utilizing a dynamic mesh equation based on the convection speed w, flux change caused by mesh motion can be directly obtained through the convection speed, and thus a numerical calculation process becomes an iteration solution process of a simple speed item U and a pressure item p. The dynamic mesh numerical solution method disclosed by the invention has the characteristics of high operation efficiency, short calculating time and low operation cost aiming at the design calculation of the internal flow field of the rotary machine.

The invention discloses a velocity estimation and friction identification method of a four-wheel turning/driving vehicle. The velocity estimation and friction identification method comprises the steps that firstly, a vehicle body coordinate system O-XY is established; secondly, a vehicle kinetic equation is established; thirdly, a wheel kinetic equation is established; fourthly, a wheel velocity equation is established; fifthly, a wheel slip rate equation is established; sixthly, the longitudinal force and lateral force of a wheel are obtained; seventhly, a friction model is parameterized; eighthly, a kinematical equation describing the relation of the vehicle velocity, the yaw velocity and the acceleration is established; ninthly, an observer is designed under the situation that detectable signals z comprise the longitudinal acceleration ax, the lateral acceleration ay, the yaw velocity r, the wheel angular velocity wj and the steering wheel rotation angle delta i; tenthly, persistent excitation conditions are defined. According to the velocity estimation and friction identification method, the nonlinearity self-adaptation observer for estimating the vehicle longitudinal velocity and the lateral velocity is established, the tire road surface friction parameters are established in real time according to the change of road surface conditions, and the velocity is estimated more accurately.

The invention discloses a movement planning method for a mechanical arm. The method comprises the following steps: A, measuring the actual position of the tail end of the mechanical arm and the expected initial position of the tail end of the mechanical arm when the mechanical arm is in an initial state, and calculating the position error of the tail end of the mechanical arm; and B, constructinga Cartesian velocity equation of the mechanical arm, and solving the joint velocity of the mechanical arm by means of pseudo-inverse Jacobian matrix combined with the Cartesian velocity equation of the mechanical arm. The method disclosed by the invention can save the calculated amount greatly, is accurate in calculating result, and can improve the executing precision of the mechanical arm effectively.

The invention relates to an enzymatic activity test method using combining integration and initial velocity method, which is characterized in that the classical initial velocity is measured when the concentration of initial substrate is 70% higher than that of the preset substrate, and the classical initial velocity is still within linearity range; when the substrate consumption proportion in 80% record period is higher than the lower limit required in integration, the fitting reaction curve of integral velocity equation is used to determine the maximum reaction velocity using reaction time as independent variable, then the maximum reaction velocity is calculated as the initial velocity with preset substrate concentration is 93%; meanwhile, the slope of classical initial velocity and computation initial velocity to the enzyme amount reaction curve; when the substrate consumption proportion of the coupling enzyme reaction system in 80% record period is higher than the lower limit required in integration, the fitting enzyme reaction curve is used to determine the initial velocity using corresponding numerical integral velocity equation, otherwise the classical initial velocity is directly measured; total time for the optimization monitoring reaction guarantees the combination of the two methods.

The invention discloses a vertical deviation measuring method based on static correction. The vertical deviation measuring method comprises the steps that an attitude, position and velocity equation,and a measuring equation of a combined system vertical deviation observation model are established; a static correction vertical deviation observation model is established; whether a carrier is in uniform motion or not is determined, and if the carrier is in uniform motion, then a position difference and a measured value of course angle correction are used as the measuring equation to correct a vertical deviation equation; otherwise, a velocity, the position difference, and the measured value of course angle correction are used as observations to correct the vertical deviation equation; and inertia system output state variables are statically corrected based on the corrected static correction vertical deviation observation model. According to the vertical deviation measuring method based on static correction, velocity information and position information are used as the observations, in the meantime, zero angle correction observations are added to limit a course angle error, constant zero offset of an angular velocity sensor is updated to reduce the course angle drift, and the problems that southern attitude error compensation during the combined system vertical deviation measuringis not satisfied and the course angle error increases with time are solved.

The method for quantitative determination of biochemical substance by means of predetermining background and making enzyme analysis includes the following steps: adding buffer solution and tool enzyme in the sample solution to be determined, measuring the change of light absorption with reaction time, and utilizing integral velocity equation to fit and analyze the negative curve of light adsorption consumed by substrate to predetermine background instead of directly detemining background. It can directly determine body fluid sample, and it has no meed of diluting said sample, and its determination accuracy is high.

The invention discloses a PML absorption boundary based three-dimensional sound wave numerical simulation method. The method mainly comprises the following steps of S1, applying regular grids in an internal computation region, and defining wave field pressure only on regular grid integer nodes; applying staggered grids in a PML absorption region, defining wave field pressure on staggered grid integer nodes, and defining particle velocity components and medium density on staggered grid half nodes; S2, updating wave field pressure values through a second-order hyperbolic partial differential wave equation in the internal computation region; calculating particle velocity components and wave field pressure values through a first-order stress velocity-equation in the PML absorption region. By the aid of the method, the memory requiring amount is reduced, the simulative model scale is expanded, and the PML boundary processing is simple. The method is particularly applicable to seismic wave numerical simulation or reverse-time migration in the oil-gas exploration field.

A methodology for generating a motion profile for an axis of a motor in a mailing apparatus, the linear or angular motion of the motor axis imparting a motion to a sheet or envelope being conveyed by the mailing apparatus. The methodology includes four processes for generating a segment of a motion profile, depending on whether, for the segment, absolute positional synchronism (of the motor axis to be controlled relative to another motor axis) is needed, or whether a so-called quick step is needed, i.e. a change in velocity corresponding to acceleration that varies during the step. The processes include: forward integration, given the jerk (acceleration per unit time) and starting acceleration as well as initial values of position and velocity; non-parabolic displacement mapping (sometimes called electronic gearing) relating the motion of the axis to be controlled to the motion of another axis where the function expressing the mapping is not parabolic in the commanded or actual position of the other axis; integration based on a velocity equation that is parabolic in time; and a parabolic displacement mapping, i.e. a displacement mapping using a function that is parabolic in the actual or commanded position of a reference axis.

The invention provides an earthquake forward modeling method applicable to non-uniform motion water bodies. The method comprises the steps that firstly, data, observation systems and hypocenter parameters related to seawater and strata are acquired; secondly, starting from the mass conservation equation, the Euler equation and the adiabatic state equation, through an asymptotic method and a suitable assumption based on the seawater practical conditions, a first-order stress-velocity equation suitable for the non-uniform motion water bodies is derived; thirdly, a reasonable boundary condition is given; finally, a control equation and the boundary condition are discretized through high-precision finite difference, and the propagation process of seismic waves in the seawater and seabed elastic media is simulated. According to the method, the influences of the density, sound velocity and flow velocity in the seawater on propagation of the seismic waves are comprehensively considered, the propagation condition of the seismic waves in a complex marine environment can be truly reflected, and the method has high application value in marine oil-gas exploration, especially deepwater oil-gas exploration in the complex marine environment.

The invention relates to a kinematics and dynamics solving iterative algorithm of an underactuated mechanism with a flexible kinematic pair. The algorithm includes the following steps: 1) establishing a coordinate system of the mechanism; 2) defining mechanism parameters, establishing a kinematic model and a dynamic model of the underactuated mechanism, and obtaining a kinematic position equation, a kinematic speed equation, a kinematic accelerated velocity equation and a dynamic equation of the mechanism; 3) giving initial condition of each component and a motion law of an original dynamic object, solving the kinematic equations and the dynamic equation of the mechanism at the time of t0, and obtaining the motion law of each component and the driving force of the original dynamic object at t0; 4) solving the kinematic equations and the dynamic equation of the mechanism at the time of tj, and obtaining the motion law of each component and the driving force of the original dynamic object at tj; 5) repeating the step 4 for n times so as to obtain the motion law of all components of the mechanism and the driving force of the original dynamic object in a whole motion cycle, drawing point by point by MATLAB, and obtaining motion raw curve of each component and a driving force change curve of the original dynamic object.

The invention discloses a high-precision precise positioning motion planning method, which comprises the following steps of: parameterizing a motion planning curve, and constructing a speed equation under the condition that the upper limit of speed is Vm and the upper limit of acceleration is am, K is a coefficient related to Vm, and tau is a coefficient related to am; and when the planned distance is x and the speed at the ta moment is x, solving according to the equation set, and if the speed is smaller than Vm, obtaining a high-precision precise positioning motion planning curve according to the equation. The high-precision precise positioning motion planning method provided by the invention can effectively improve the problem of time delay, has the characteristic of asymmetric acceleration and deceleration, and is simple in operation equation and small in calculation amount.

A system, method, and apparatus is described for providing a reduced or moderated gravity environment in a terrestrial payload. The system includes the evaluation of terrain to support an appropriately shaped vehicle guide, the construction of a vehicle guide, the provision of a high-speed vehicle and a control system adapted to control a motion of the vehicle across the vehicle guide with a specific velocity profile so as to produce a moderated gravity environment.

The invention relates to a land-based system, a method and a facility to provide a low-gravity or gravity-modulation environment. The system comprises a structure for estimating topography and imitation, and a vehicle guider for supporting verticality, and provides a vehicle and control system to control the movement of the vehicle; and the vehicle is moved along the guider according to a specific velocity equation so as to generate a selected environment for modulating the gravity.

The invention provides a method and device for determining the target speed of S-shaped speed planning, which belongs to the technical field of numerical control machining. The method comprises steps of acquiring cutter motion parameters, determining a target speed equation about the target speed according to the cutter motion parameters, solving the target speed equation by adopting a Lagrange interpolation method to obtain a target speed, and controlling the cutter to move according to the target speed. According to the method, a plurality of target function equations related to the target speed are obtained by analyzing the numerical relationship of each motion parameter under different values, and a method for solving the target function parameters by using the Lagrange interpolation method is provided for the target speed equation with the high-order term, the problem caused by complexity when a numerical value method represented by a bisection method and a Newton method is used for solving target function parameters is solved to a great extent, the real-time performance of the S-shaped speed planning process is improved, and the requirement for the hardware computing power of a numerical control machine tool is lowered.