scholarly journals Mathematical Approach in Complex Surfaces Toolpaths

Mathematics ◽  
2021 ◽  
Vol 9 (12) ◽  
pp. 1360
Author(s):  
Florin Popișter ◽  
Daniela Popescu ◽  
Ancuţa Păcurar ◽  
Răzvan Păcurar
Keyword(s):  
Point Cloud ◽  
Point Clouds ◽  
3D Scanning ◽  
Numerical Control ◽  
Mathematical Approach ◽  
End Mill ◽  
Complex Surfaces ◽  
Ball End Mill ◽  
Scanning Process ◽  
Control Machine

This paper represents the focus on developing efficient algorithms that reduce the operations required to be employed in order to obtain complex surfaces milling finishing toolpaths for the three axis NC (Numerical Control) machine within the reverse engineering chain of processes. Direct machining is the process of generating efficient toolpaths directly from the digitized data, meaning the point cloud. The entire research is focused on determining the mathematical calculus able to interpret the data collected through the contact/noncontact 3D scanning process. In this direction, two algorithms were developed to generate ball-end mill finishing toolpaths for freeform surfaces using ordered/unordered point clouds. Practical work that validates author’s employed algorithms of obtaining finishing milling toolpaths uses the point cloud stored from the 3D scanning process in matrix found in ASCII files, which makes data interpreting easy.

On the Flexible Abrasive Tool for Nanofinishing of Complex Surfaces

2019 ◽  
Vol 18 (01) ◽  
pp. 157-166 ◽  
Author(s):  
Mithun Sarkar ◽  
V. K. Jain ◽  
Ajay Sidpara
Keyword(s):  
Surface Roughness ◽  
Corrosion Inhibitor ◽  
Abrasive Tool ◽  
End Mill ◽  
Complex Surfaces ◽  
Ball End Mill ◽  
Workpiece Surface ◽  
Abrasive Particles ◽  
Processing Step ◽  
Finishing Tool

Nanofinishing of complex surfaces is an important but costly processing step for many products for performing their functions satisfactorily. This paper deals with the development of a flexible abrasive tool for nanofinishing of complex surfaces. A flexible finishing tool similar to the ball end mill is developed by curing Polydimethylsiloxane (PDMS). A bowl-shaped copper workpiece is finished to nanometer surface roughness value. Different sizes of abrasive particles are used to reduce surface roughness value of the workpiece. A corrosion inhibitor is mixed with the abrasive slurry to protect the finished copper workpiece surface. A final surface roughness value of 50[Formula: see text]nm has been achieved with a variation up to 70[Formula: see text]nm on different locations of the bowl-shaped workpiece.

Converting Point Cloud to Revolved Solids

2013 ◽  
Vol 371 ◽  
pp. 468-472
Author(s):  
Mircea Viorel Drăgoi ◽  
Slobodan Navalušić
Keyword(s):  
Reverse Engineering ◽  
Cross Section ◽  
Software Package ◽  
Point Cloud ◽  
3D Model ◽  
Point Clouds ◽  
3D Scanning ◽  
Main Drawback ◽  
Mass Properties

3D scanning is one of the basic methods to gather data for reverse engineering. The main drawback of 3D scanning is that its output - the point cloud - can never be used directly to define surfaces or solids useful to reconstruct the electronic 3D model of the scanned part.The paper presents a piece of software designed in VisualLISP for AutoCAD, software that acts as a point cloud to 3D primitives converter. The novelty consists of the method used to find the parameters of the primitive that best fits to the point cloud: the mass properties of regions are used to find the center of a cones cross section. Parts have been scanned and the point clouds processed. The results obtained prove the correctness of the algorithm and of the method applied. A piece of software that processes the point cloud in order to find the 3D primitive that it fits the best has been developed. The output is the 3D primitive that successfully and accurate replaces the point cloud. Some adjacent tools were designed, so the entire software package becomes a useful tool for the reverse engineering user. The ways the researches can be continued and developed are foreseen, as well

Application of the 'Iterative Closest Point' Algorithm for Determination of Rotation Axis of a Turntable

2013 ◽  
Vol 199 ◽  
pp. 273-278
Author(s):  
Ireneusz Wróbel
Keyword(s):  
Reverse Engineering ◽  
Point Cloud ◽  
Rotation Axis ◽  
Rapid Development ◽  
Point Clouds ◽  
Iterative Closest Point ◽  
Mechanical Parts ◽  
Scanning Process ◽  
Iterative Closest Point Algorithm

Reverse engineering [ is a field of technology which has been under rapid development for several recent years. Optic scanners are basic devices used as reverse engineering tools. Point cloud describes the shape of a scanned object. Automatic turntable is a device which enables a scanning process from different viewing angles. In the paper, the algorithm is described which has been used for determination of rotation axis of a turntable. The obtained axis constitutes the base for an aggregation of particular point clouds into single resultant common cloud describing the shape of the scanned object. Usability of this algorithm for precise scanning of mechanical parts was validated, precision of shape replication was also evaluated.

A Novel CNC Grinding Method for Relief Surface Based on a CAM System

2011 ◽  
Vol 295-297 ◽  
pp. 2521-2525 ◽  
Author(s):  
Xiao Feng Yue ◽  
Fei Tang ◽  
Shu Zhe Li ◽  
Zhan Hua You ◽  
Xiao Hao Wang
Keyword(s):  
Coordinate System ◽  
Numerical Control ◽  
Grinding Wheel ◽  
End Mill ◽  
Ball End Mill ◽  
Relief Surface ◽  
Cnc Grinding ◽  
Relief Angle ◽  
Five Axis ◽  
Mill Machining

A novel algorithm for the ball-end mill relief using a five-axis computer numerical control (CNC) grinding machine and the simulation of the ball-end mill based on a CAM system is presented in this paper. In this study, In order to obtain an accurate normal relief angle, which is one of the key factors affecting tool cutting performance, a tool coordinate system based on the required relief angle and the cutting edge was established. Then, by the proposed tool coordinate system, an algorithm to determine the position between the grinding wheel and the tool is proposed, and then the relevant formulations are deduced. The coordinates of grinding point when the step of relief surface is grinded are calculated.Using the input data of a ball-end mill geometry, wheels geometry, wheel setting and machine setting, the NC code for machining will be generated. Then the code will be used as input to simulate the ball-end mill machining in 3 Dimension before real machining. The algorithm of ball-end mill relief can be authenticated by the 3D simulation system.

scholarly journals Representative Construction Engineering Drawings Combining SLAM and Ground-Based LiDAR

2021 ◽  
Vol 2112 (1) ◽  
pp. 012017
Author(s):  
Chutian Gao ◽  
Ming Guo ◽  
Zexin Fu ◽  
Dengke Li ◽  
Xian Ren ◽  
...  
Keyword(s):  
Point Cloud ◽  
Point Clouds ◽  
3D Scanning ◽  
Single Type ◽  
Point Cloud Data ◽  
Cloud Data ◽  
Outdoor Scenes ◽  
Engineering Drawings ◽  
Ground Based Lidar ◽  
Indoor And Outdoor

Abstract Obtaining architectural engineering drawings is a crucial aspect of upgrading and repairing structures. Traditional elevation measuring is ineffective and results in a poor rate of restoration. The current building elevation measurement solutions based on 3D scanning technology all obtain building 3D point cloud data from a single type of laser scanner. These two methods can’t get both indoor and outdoor scenes at the same time. This paper presents a scanning strategy that combines SLAM with Ground-based LiDAR to solve this problem. The point cloud data for the building’s indoor and outdoor scenes are obtained independently, and the Ground-based LiDAR point cloud data is registered locally using the iterative closest point(ICP) algorithm. The SLAM point clouds and the Ground-based LiDAR point clouds are then registered as a whole to develop an overall model of the building using point constrained error equations. For various reasons, the building can be trimmed into a planar point cloud model depending on the application. Finally, engineering drawings for the construction of the building can be drawn. The method’s viability was demonstrated by using it in a 3D scanning project of a scenic site in Beijing. This technology improves model information interpretability, scanning efficiency, and provides powerful data assistance for building rehabilitation and repair. It is extremely important in the disciplines of urban planning, rehabilitation, and historic preservation. After performing a more optimal preprocessing, more than 90% classification accuracy was achieved across 18 low-power consumer devices for scenarios in which the in-band features-to-noise ratio (FNR) was very poor.

scholarly journals Curvature Adaptive 3D Scanning Transformation Calculation

2018 ◽  
Vol 62 (4) ◽  
pp. 107-116
Author(s):  
Adrián Mezei ◽  
Tibor Kovács
Keyword(s):  
Real Time ◽  
Point Cloud ◽  
Three Dimensional ◽  
Point Clouds ◽  
3D Scanning ◽  
Laser Line ◽  
3D Scanner ◽  
Three Dimensional Objects ◽  
Laser Scanners ◽  
Set Up

Three-dimensional objects can be scanned by 3D laser scanners that use active triangulation. These scanners create three-dimensional point clouds from the scanned objects. The laser line is identified in the images, which are captured at given transformations by the camera, and the point cloud can be calculated from these. The hardest challenge is to construct these transformations so that most of the surface can be captured. The result of a scanning may have missing parts because either not the best transformations were used or because some parts of the object cannot be scanned. Based on the results of the previous scans, a better transformation plan can be created, with which the next scan can be performed. In this paper, a method is proposed for transforming a special 3D scanner into a position from where the scanned point can be seen from an ideal angle. A method is described for estimating this transformation in real-time, so these can be calculated for every point of a previous scan to set up a next improved scan.

Modeling and Simulation of Milling Force in Virtual Numerical Control Milling Process

2008 ◽  
Vol 392-394 ◽  
pp. 697-702
Author(s):  
Xiu Lin Sui ◽  
Jia Tai Zhang ◽  
Jiang Hua Ge ◽  
Ya Ping Wang ◽  
H. Yuan
Keyword(s):  
Modeling And Simulation ◽  
Chip Thickness ◽  
Milling Process ◽  
Cutting Edge ◽  
Numerical Control ◽  
Force Model ◽  
End Mill ◽  
Ball End Mill ◽  
Milling Force ◽  
Milling Force Model

A parameter equation based on cutting edge of ball-end mill is set up by analyzing the parameters of ball-end mill influence the milling force in virtual NC milling process. The relationship among elemental cutting force, instantaneous radial chip thickness and cutting edge length is analyzed, and the dynamic milling force of ball-end mill at arbitrary feed direction is established. The milling force parameter model by quadratic regression equation in different cutting conditions is built. Through experiments in NC machining center and using orthogonal combination and principal components analysis, the regression coefficients are calculated. The correctness of milling force model is testified by experiments. All these can provide theoretical basis for physics modeling and simulation of virtual numerical control milling.

Registration and Fusion of UAV LiDAR System Sequence Images and Laser Point Clouds

2020 ◽  
Author(s):  
Jiayong Yu ◽  
Longchen Ma ◽  
Maoyi Tian, ◽  
Xiushan Lu
Keyword(s):  
Point Cloud ◽  
Image Data ◽  
Point Clouds ◽  
Optical Image ◽  
Point Cloud Data ◽  
Feature Points ◽  
Lidar System ◽  
Registration Accuracy ◽  
Cloud Data ◽  
Intensity Image

The unmanned aerial vehicle (UAV)-mounted mobile LiDAR system (ULS) is widely used for geomatics owing to its efficient data acquisition and convenient operation. However, due to limited carrying capacity of a UAV, sensors integrated in the ULS should be small and lightweight, which results in decrease in the density of the collected scanning points. This affects registration between image data and point cloud data. To address this issue, the authors propose a method for registering and fusing ULS sequence images and laser point clouds, wherein they convert the problem of registering point cloud data and image data into a problem of matching feature points between the two images. First, a point cloud is selected to produce an intensity image. Subsequently, the corresponding feature points of the intensity image and the optical image are matched, and exterior orientation parameters are solved using a collinear equation based on image position and orientation. Finally, the sequence images are fused with the laser point cloud, based on the Global Navigation Satellite System (GNSS) time index of the optical image, to generate a true color point cloud. The experimental results show the higher registration accuracy and fusion speed of the proposed method, thereby demonstrating its accuracy and effectiveness.

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