Papers by Keyword: Data Points

Abstract: The inside profile curves data points of vole’s clawed toes had been analyzed. The least squares fitting method was used to analyze the inside profile curves data points for fitting mathematical model and fitted curves were expressed by polynomial equations. According to the curvature of fitted curves, the geometrical characteristics of the fitted curves were summed up. The variation curvature of inside profile curve from the second clawed toe was similar to the third and fourth. They both had two maximum vales and two minimum vales, and the larger maximum vales were at the tiptoes, the smaller maximum vales were at the end of toes’ babies. The fifth clawed toe had only one maximum vale and two minimum vales. And one of the minimum vales was at the tiptoe, another was at the end of toe’s baby. The maximum vale was in the center of the fifth clawed toe’s body. This concluded that the geometrical characteristics of inside profile curves were very important for vole’s digging ability. This provided design reference of energy-saving and high efficient for structure design of soil contact surface of tillage components.

Abstract: In the field of reverse engineering, data quality assessment is a very important work in the detection, the result of data quality assessment will directly or indirectly affect the detection and the following manufacturing process quality. Data quality assessment can be used in the camera calibration, the model and model reconstruction comparison, and so on. In this paper, on the basis of the existing method of calculating each point error, and multipurpose use of average and standard error and some other concepts of mathematical statistics, and then improve a novel and simple calculating error method. This method is applicable to many groups of one-to-one ideal data and the measured data comparison, and it can be more intuitive to reflect the error of overall data, as well as the error distribution, and it can be more efficient to determine the measured data is reasonable or not. In this paper, the data point quality which is collected in the reverse engineering is assessed, and it can see that the method which is proposed in this article has some advantages in the data point quality assessment field.

Abstract: The algorithm to obtain intersecting lines from section and equidistance surface is one method of resolving the problem of obtaining NC machining procedure from points cloud data. As far as cutter paths obtained by section method are concerned, if intersecting lines using tangent plane and processed curved surface are obtained directly, it will be a quite complicated process and lead to divergent iteration operation because of inconsiderate design algorithm, and therefore it leads to the failure of obtaining intersecting lines. So the method of obtaining intersecting lines from section and equidistance surface is adopted. And this paper put forward and has realized one new algorithm. The calculation is simple and the algorithm is stable. It avoids the interference of cutting tool paths.