Papers by Keyword: Corner

Abstract: When milling corners in high speed, it will lead the mutation of cutting force that affects the processing quality and processing efficiency. In order to study the influence of milling parameters on milling force in the corner. Firstly, an orthogonal experimental of corner is designed to study the influence of various cutting parameters on cutting force. Axial cutting depth, radial depth, spindle speed and feed speed, as the major influence factors, impact on cutting force in corner milling. Then, a cutting force model of corner is established based on a method of orthogonal experiment linear regression. The significance test of regression equation and regression coefficient shows that cutting force model is accurate. The cutting force model is used to predict the cutting force, and then select the appropriate cutting parameters.

Abstract: This paper studies a problem which is the rapid acquisition feature information of moving targets in a video sequence. Selecting the harris algorithm as a feature extraction algorithm, but harris algorithm has a problem of running slowly .Opting 3 * 3 window as the detection window, analyzing the similarity between the window capacity pixel and central pixel, then using the difference to measure this similarity of pixels, when the difference is greater than the set threshold value, we thought they are different, otherwise they are similar.After that characteristics of regional screening was completed. The target areas were divided into feature areas and non-feature regions, but we only calculated the response functions of characteristic areas. The algorithm^’s executing efficiency improved.

Abstract: High speed machining of the corner of hardened steel mould has a great influence to the entire product performance of the mould. In this paper, with the single factor experiments, the influence of feed per tooth, cutting speed and angle of the corner to the cutting forces, the vibration value and the surface roughness were analyzed. And the cutting parameters were optimized. The cutting forces, vibration value and surface roughness value of the corner of the mould reached the minimum value when the cutting speed was 80 m/min and the feed per tooth was 0.006 mm/z in the experiment. The surface quality of corner with angle of 90^o was better than the corner with angle of 60^o and 120^o with various milling parameters.

Abstract: Corner machining accuracy has always been one of the important properties of WEDM. In this paper, the reasons for the corner error of the WEDM were discussed. Then the mathematical deflection model of the electrode wire was established. By experimental measurements, the kerf width and the deflection of the electrode wire were obtained. Then the corner control strategy of the WEDM was proposed. Through experiment of the Comparison of corner error between control strategy with corner control and the one without corner control, it shows that the processing accuracy was improved effectively.

Abstract: Starting from the goal to overcome the limitation of the single type algorithm of iris recognition. In this paper, a two-step iris recognition algorithm is proposed based on feature extraction on corner and Gabor transform .First of all, it uses the corner feature of iris texture to recognize for achieving the purpose of removal of alien and confirm the vast majority of similar samples rapidly; if it unabes to determine the category in the first step, the result of the first step is used as the initial angle in normalized phase, and then it carries out iris feature extraction and recognition based on Gabor transform. The experimental results show that this results the speed and performance in the recognition improved significantly than the traditional algorithm of single feature recognition.

Abstract: The behavior of pedestrians around the corner of a room or a corridor is one of the most important features in pedestrian evacuating dynamics. In order to study this in detail, an existing potential field model is modified to capture the pedestrian dynamic around corner by introducing a local density parameter. The local density parameter of a cell is defined as the pedestrian occupancy of the surrounding eight neighbors. Simulations are carried out to study pedestrian evacuation in rooms with corners formed by internal obstacles and walls. The simulation results show that the new model can reproduce the empirical pedestrian dynamics around corner. Pedestrians prefer to walk to lower pedestrian density area although the route may be a little longer. It is also shown that the total evacuation time could be reduced for the evacuation corridor is fully utilized.

Abstract: As the offshore drilling expands to deep water, the influences of bottom ball joint corner and lateral force on drilling security become increasingly significant. During the force analysis, the environmental factors (e.g. wind, sea-flow force, sea ice, etc.) are usually taken into account. Besides, the engineering factors considered in research are top tension ratio and drilling vessel drift. In this paper, a finite element model is established by ANSYS to imitate the force condition of marine riser, so as to analyze the influence laws of top tension ratio and drilling vessel drift rate on marine riser stability (i.e. the corner and lateral force on bottom ball joint ) in Beaufort force scale 3 and 8 windy conditions. The results show that the lateral force increases with the drilling vessel drift rate and top tension ratio accordingly by linear mode. For the same tension increasing extent, the greater the drilling vessel drifts, the more increasing range the lateral force appears. The corner on bottom ball joint has a linear relation with the drilling vessel drift rate similarly. However, the corner on the bottom ball joint demonstrates a non-linear decreasing method as “fast followed by slow” due to the increasing top tension ratio. The research plays a role in the security assurance of sub-sea wellhead in deep-water drilling operation.

Abstract: Matching feature points is an important step in image registration. For high- dimensional feature vector, the process of matching is very time-consuming, especially matching the vast amount of points. In the premise of ensuring the registration, filtering the candidate vectors to reduce the number of feature vectors, can effectively reduce the time matching the vectors. This paper presents a matching algorithm based on filtering the feature points on their characteristics of the corner feature. The matching method can effectively improve the matching speed, and can guarantee registration accuracy as well.

Abstract: Pocket corner in the high-speed milling (HSM) often occur under-cut, over-cut, vibration and other phenomena. This not only reduces tool life, seriously affected the work-piece machining accuracy and processing efficiency. In the paper, the impact of cutting speed on cutting forces is studied in the pocket corner based on the high-speed milling experiments. The results show that cutting force increased slightly with the increase in cutting speed, and that cutting force no significant change with the increase in radial depth of cut.

Abstract: In milling pocket corner, there maybe residual material left at sharp corners when stepover is extremely large in contour-parallel toolpath. This paper describes an improved pocket toolpath by inserting biarc transitions segments in contour-parallel toolpath. When reaching the sharp corner, the cutter moves along the biarc transitions toolpath so that the corner material is removed. The efficient toolpath is continuous for clearing residual material at sharp corner. Milling test has been conducted to demonstrate and verify the significance of the proposed method.