32 results about "Stability Model" patented technology

The invention discloses a method for determining the safe drilling fluid density of a coal bed based on a structural element analysis model. The method has the advantages of coal bed cleat and fracture development, big rock brittleness, low strength and obvious anisotropy and discontinuity. The borehole wall instability characteristics of the method are different from those of the common sandstone stratum. The phenomenon that the traditional borehole wall stability model based on the mechanics of continuous media is difficult to be successful for solving coal bed instability problems can be eliminated. In the method, the coal bed is composed of discrete blocks. A coal briquette which has the biggest possibility of generating spallation between surface cleats is analyzed to carry out force analysis. A structural element model of collapse pressure is built by the stressed balance condition among pressure stress, shearing strength and shaft pressure. A coefficient c is introduced to judge the stable relationship of borehole pressure and borehole wall so as to judge the range of the safe drilling fluid density.

The invention belongs to the field of milling processing, and specifically discloses a processing trajectory optimization method based on parameterized milling force and stability constraints. Including: considering the tool axis runout and tool attitude changes, constructing the tool cutting force model, and at the same time building the milling stability model; taking the stability model as a constraint, according to the tool cutting force model to obtain the control hard point in different tool attitudes and feeds The cutting force value of the tool under the direction, and use this to classify the angle parameters of the tool attitude, so as to construct the angle parameter classification model of the non-control hard point on the parametric surface; according to the digital angle parameter classification table of a control hard point corresponding to An ideal tool path is induced by the optimal tool pose of ; with the residual height as a constraint, all tool paths on the parametric surface are obtained. The method of the invention can plan a tool path with relatively small cutting force, which is beneficial to improving the surface quality of the workpiece, processing efficiency, tool durability and the like.

The invention discloses a method for synergistic control of speed of mixed traffic in a merge area based on stability analysis, specifically: with "1+ N "The form constitutes a vehicle cluster, "1" represents an intelligent self-driving vehicle CAV," N "Represents the following multiple artificial vehicles HV; build an intra-cluster stability analysis model, and analyze the intra-cluster stability conditions; under the premise of satisfying the intra-cluster stability conditions, build an inter-cluster stability model, and analyze the inter-cluster stability conditions; based on Cluster and inter-cluster stability conditions, build cluster synergy speed control model, under satisfying cluster and inter-cluster stability conditions, guide the incoming cluster to enter the confluence area smoothly by controlling the CAV speed. The present invention takes the expressway confluence area as research Object, the speed cooperative control model is built on the premise of stability, which improves the accuracy, effectively reduces the risk of traffic flow, improves the dynamic space occupancy rate and reduces exhaust emissions.

The invention discloses a quartz flexure accelerometer parameter stability modeling method, namely a parameter stability modeling method for a quartz flexure accelerometer based on a random point degradation model. The method comprises the steps that first, the degradation model containing random change points is established; second, a likelihood function of observation data is estimated; third, a deficient number is separated from the observation data; and fourth, parameter estimation is performed through an EM algorithm. Through the steps, the degradation model is established through product main performance parameters, test cost and test time are saved for products with high construction cost, high reliability and long service life, and the method has practical significance; an accelerometer parameter stability model is established and the random change points are estimated mainly targeting the problem of poor parameter repeatability of the quartz flexure accelerometer to make sure accelerometer parameters gets into a stable profile cycle number, and the method has huge practical significance in practical engineering application.