10 results about "Rational polynomial" patented technology

The application discloses a stable domain constraint trajectory planning and control method for a modular distributed electric drive heavy load vehicle, comprising the following steps: constructing a nonlinear dynamics model of the modular distributed electric drive heavy load vehicle, fitting a tire lateral force model through a rational polynomial, and establishing a vehicle system state space expression based on the rational polynomial form; adopting a sum of squares planning method to estimate the stable domain of the vehicle under different vehicle speeds, road adhesion coefficients and front, middle and rear wheel turning angles, and analyzing the influence of each state quantity on the shape and boundary of the stable domain; embedding the stable domain constraint into a trajectory planning layer based on a quintic polynomial to generate an obstacle avoidance trajectory meeting the dynamics stability; designing a multi-axle proportional steering strategy based on a steady state assumption, and combining a nonlinear model predictive controller to realize trajectory tracking control, so that the stability and control feasibility of the vehicle in a high-speed dynamic obstacle avoidance process are ensured. Through construction of a high-speed dynamic obstacle avoidance simulation scene, the effectiveness, stability and control feasibility of the stable domain constraint trajectory planning and control framework are verified.

The application discloses a kind of remote sensing image processing systems based on computer vision, belong to remote sensing image processing technical field, comprising: multi-source data space-time registration and parameter analysis module;Surface illumination prior construction module;Variational energy functional construction module;Partial differential equation iterative solution module and geoscience threshold classification module.In the application, rational polynomial model is used to complete the orthorectification and spatial registration of multi-source remote sensing image and elevation data, combined with the surface normal vector matrix and the sunlight direction vector at the imaging moment, the physical illumination prior that fits the real ground imaging environment is constructed, the direct light, the diffuse reflection component and the terrain sheltered shadow area are distinguished;Then construct multi-constraint optimization target through logarithmic domain variational energy functional, adopt alternating direction multiplier method to solve iteratively, accurately strip illumination field and real ground reflectivity.

This invention provides a method, apparatus, and device for joint calibration of optical satellite constellations, applicable to the field of satellite data processing technology. The method includes: performing small-side-swing imaging on multiple global geometric calibration fields to establish a rigorous geometric positioning model and generate initial rational polynomial parameters; selecting a reference region for dense matching to obtain dense matching points and calculating the payload's internal azimuth parameters and initial external azimuth elements; performing sparse matching on other regions to obtain sparse matching points; and establishing a joint calibration model based on the dense and sparse matching points, obtaining the optimal external calibration parameters through weighted calculation. This invention, by jointly utilizing data from multiple global calibration fields and uniformly calculating the geometric parameters of satellites within a constellation, effectively overcomes the local overfitting problem caused by a single calibration field, significantly improving the consistency of geometric positioning accuracy of satellites within a constellation globally.

The present application provides a kind of longitude cross positive and negative 180 degrees satellite data geometric processing method, device and equipment, it is related to satellite data processing technical field.The geometric processing method includes: obtaining the initial longitude range corresponding to satellite data, in the case where initial longitude range crosses positive and negative 180 degrees, initial longitude range is corrected, and the modified longitude range is obtained;The elevation data corresponding to the modified longitude range is spliced across 180 degrees meridian, and the spliced elevation data is obtained;Based on the space grid of spliced elevation data, the grid point longitude value of space grid is corrected, and the rational polynomial function model is established according to the grid point longitude value after modification;Based on rational polynomial function model and spliced elevation data, generate the product after geometric correction.

The application provides an optical constellation joint calibration method, device and equipment, which can be applied to the technical field of satellite data processing. The method comprises the following steps: imaging a plurality of global geometric calibration fields with a small side swing angle, establishing a strict geometric positioning model and generating initial rational polynomial parameters; selecting a reference area for dense matching to obtain dense matching points and solve load inner orientation parameters and initial outer orientation elements; performing sparse matching on other areas to obtain sparse matching points; and establishing a joint calibration model based on the dense matching points and the sparse matching points, and obtaining optimal outer calibration parameters through weighted solving. The application jointly uses data of a plurality of global calibration fields, uniformly solves geometric parameters of satellites in a constellation, effectively overcomes a local overfitting problem caused by a single calibration field, and significantly improves the geometric positioning accuracy consistency of the satellites in the constellation in a global range.

The application discloses a method and system for expanding a vehicle stability domain estimated by a sum-of-squares programming algorithm, and belongs to the technical field of computers, and comprises the following steps: a rational polynomial-based whole vehicle polynomial model is constructed by combining a two-degree-of-freedom dynamics model of a vehicle and a rational polynomial nonlinear tire model; a vehicle stability region is estimated by a sum-of-squares programming algorithm based on the whole vehicle polynomial model, and a stability region boundary curve is obtained; the stability region boundary curve is subjected to discrete processing, and an initial point set is obtained; a convex hull of a stability domain expansion is obtained by trajectory inversion according to the stability region boundary curve and the initial point set; and the convex hull of the stability domain expansion is taken as an expanded stability region. The application can realize maximum estimation of a stability domain boundary, greatly improve the conservativeness of the stability domain, make the judgment of vehicle stability more accurate, and be favorable to improving the reliability of vehicle stability control.

This invention discloses a computer vision-based remote sensing image processing system, belonging to the field of remote sensing image processing technology. It includes: a multi-source data spatiotemporal registration and parameter analysis module; a land surface illumination prior construction module; a variational energy functional construction module; a partial differential equation iterative solution module; and a geoscientific threshold classification module. In this invention, a rational polynomial model is used to complete orthorectification and spatial registration of multi-source remote sensing images and elevation data. Combining the land surface normal vector matrix and the solar illumination direction vector at the imaging time, a physical illumination prior that fits the real terrain imaging environment is constructed, distinguishing between direct illumination, diffuse reflection components, and terrain-occluded shadow areas. Then, a multi-constraint optimization objective is constructed through a logarithmic domain variational energy functional, and the alternating direction multiplier method is used for iterative solution to accurately separate the illumination field from the real land surface reflectivity.

The invention discloses a remote sensing image block adjustment method based on a quadratic polynomial model. The method comprises the following steps: constructing a compensation model of block adjustment according to a quadratic polynomial; determining image space normalized coordinates according to the object space coordinates and a rational polynomial model; determining image space theoretical coordinates according to the image space normalization coordinates and the image normalization parameters; constructing an error model according to the compensation model, the image space theoretical coordinates and the image space measurement coordinates; and solving the error model by adopting a least square method to obtain a value of a compensation model coefficient. The quadratic polynomial model is used as the block adjustment compensation model, the compensation model can compensate for high-order distortion, and the block adjustment precision is improved. The invention further discloses a device for implementing the method, electronic equipment and a computer readable storage medium.

The present application belongs to the technical field of optical remote sensing, and discloses a method and system for atmospheric refraction correction of an optical satellite geometric model. First, satellite position information and atmospheric refractive index information are obtained, then the position information of light reaching the ground after atmospheric refraction correction is calculated according to the original rational polynomial model, satellite position information and atmospheric refractive index information, after that, the virtual three-dimensional grid points are re-established in combination with the position information of light reaching the ground after atmospheric refraction correction, and the coefficients of the rational polynomial model after atmospheric refraction correction are solved, finally, the coefficients of the rational polynomial model after atmospheric refraction correction are applied to the original rational polynomial model to obtain the rational polynomial model after atmospheric refraction correction. The present application can use the rational polynomial model after atmospheric refraction correction to perform geometric positioning of optical satellite images. The present application takes into account the influencing factors of atmospheric refraction, and can effectively improve the geometric positioning accuracy of optical satellite images.