Machine simulation of additive manufacturing tool path

The application of new additive technologies is based on models STL models of prototypes that will be build. This paper discusses two additive technologies: Fused Deposition Modeling – FDM and Laser Metal Directed Energy Deposition – Laser DED in terms of program preparation and its verification by simulation of material addition, i.e. machine simulation for these procedures. The paper presents the programming and program verification using machine simulation of additive manufacturing tool path in CAD/CAM and Vericut environment. A procedure for configuring and preparing of a virtual machine for several additive process simulations has been proposed. Simulation is a key technology for program verification. Machine simulation and digital twin are the primary simulation–based approaches in the context of the Industry 4.0. The paper analyzes the available programming software for generating G code from the STL file as well as the possibility of simulating the virtual machine when working according to the generated program

Simulation based parameterization for process monitoring of machining operations

Process monitoring can prevent machine and tool failure in metal-cutting. A successful process monitoring of cutting processes depends on reliable monitoring limits for the process. In industrial applications these limits have to be generated in a learning phase during a ramp-up process. In order to enable process monitoring for single batch production without a learning phase, this paper describes a simulation based approach for generating reference data to set process limits. As a foundation for calculation of monitoring limits a position-based process simulation has to be established. In a first step an approach of modeling material removal is evaluated to check whether it fits the application for parameterizing the process monitoring. In this context the potentials of a process simulation for calculating process limits are clarified. Additionally the quality of data generated by this kind of simulation is discussed. In a second step a method is described to implement machine properties by a virtual machine tool within a simulation of material removal. For that purpose a method to use actual data of axis position and tool within the simulation of material removal is necessary. With these data a way-based simulation of material removal can generate reference parameters for monitoring limits instead of using data from a learning phase during the ramp-up process. By using position data of a virtual machine tool a reliable source for the actual position of all axes enables the position-based simulation to perform material removal in a more accurate way

Modeling of 3D swept volumes using sde/sede methods and its application to five-axis nc machining

This research falls in two important areas in solid modeling and manufacturing automation: (1) swept-volume modeling; (2) computer-based NC (Numerically controled) machining simulation and verification. The swept volume is defined as the volume swept by an object undergoing an arbitrary motion. Modeling of 3D swept volumes includes the boundary computation and representation of a swept volume generated by a general object undergoing general motion in three dimensional space. The Sweep Differential Equation (SDE) and Sweep Envelope Differential Equation (SEDE) methods are two of the important swept volume modeling methods employed in this dissertation. They exploit differential equations to obtain the boundary points of a swept volume generated by a moving object. The application of SDE/SEDE methods is addressed to computer-based NC simulation and verification. Comparison of the SDE/SEDE approach with other swept volume modeling methods is conducted too. It has been shown that the SDE and SEDE methods have great benefits in calculating and representing general swept volumes and the research has substantially advanced existing manufacturing technologies. The main contributions of the research are: (1) The SDE method has been extended to three dimensional space to represent cutter swept volumes generated by moving five-axis NC milling tools. A SDE sweep generator, which can represent and analyze three-dimensional swept volumes generated by flat-end and ball-end tools for a typical five-axis NC milling machine graphically, has been developed. In the SDE sweep generator, a machine control data based interpolation method is uniquely used to describe the interpolation motion equation of a five-axis NC milling tool. (2) The SEDE method is derived for a more efficient swept volume calculation. A SEDE-based algorithm for the numerical boundary computation of swept volume is described and combined with some novel smooth approximation formulas in order to calculate the swept volume generated by a general 7-parameter APT (Automatic Programming Tool) tool for a large class of sweeps that includes the motions encountered in five-axis NC milling processes. The SEDE approach for the most part reduces the computation to the determination of SEDE trajectories at the initial grazing points (the main part of the boundary of a swept volume) of the tool, and therefore appears to reduce computational cost as well as providing a natural connectivity for most points on the swept volume boundary. (3) An SEDE-based program has been integrated with Deneb Robotics\u27s Virtual NC commercial software. The SEDE module is used to replace Virtual NC\u27s convex hull sweep algorithm for a more accurate geometrical tool swept volume representation. By using the Boolean subtractor and verifier in Virtual NC, material removal of five-axis NC milling process is simulated and analyzed in an interactive machining environment. Furthermore, the SDE/SEDE approach has been integrated with a five-axis NC milling CAD/CAM system at NJIT to perform part design, tool path generation, Cutter Location (CL) and NC code simulation and verification, and actual machining on a FADAL VMC-20 five-axis NC milling machine. Several examples including machining of a turbine impeller are given to illustrate the effectiveness of this integration approach

Digital Availability of Product Information for Collaborative Engineering of Spacecraft

In this paper, we introduce a system to collect product information from manufacturers and make it available in tools that are used for concurrent design of spacecraft. The planning of a spacecraft needs experts from different disciplines, like propulsion, power, and thermal. Since these different disciplines rely on each other there is a high need for communication between them, which is often realized by a Model-Based Systems Engineering (MBSE) process and corresponding tools. We show by comparison that the product information provided by manufacturers often does not match the information needed by MBSE tools on a syntactic or semantic level. The information from manufacturers is also currently not available in machine-readable formats. Afterwards, we present a prototype of a system that makes product information from manufacturers directly available in MBSE tools, in a machine-readable way.Comment: accepted at CDVE201

A novel haptic model and environment for maxillofacial surgical operation planning and manipulation

This paper presents a practical method and a new haptic model to support manipulations of bones and their segments during the planning of a surgical operation in a virtual environment using a haptic interface. To perform an effective dental surgery it is important to have all the operation related information of the patient available beforehand in order to plan the operation and avoid any complications. A haptic interface with a virtual and accurate patient model to support the planning of bone cuts is therefore critical, useful and necessary for the surgeons. The system proposed uses DICOM images taken from a digital tomography scanner and creates a mesh model of the filtered skull, from which the jaw bone can be isolated for further use. A novel solution for cutting the bones has been developed and it uses the haptic tool to determine and define the bone-cutting plane in the bone, and this new approach creates three new meshes of the original model. Using this approach the computational power is optimized and a real time feedback can be achieved during all bone manipulations. During the movement of the mesh cutting, a novel friction profile is predefined in the haptical system to simulate the force feedback feel of different densities in the bone

Design of New Dispersants Using Machine Learning and Visual Analytics

Artificial intelligence (AI) is an emerging technology that is revolutionizing the discovery of new materials. One key application of AI is virtual screening of chemical libraries, which enables the accelerated discovery of materials with desired properties. In this study, we developed computational models to predict the dispersancy efficiency of oil and lubricant additives, a critical property in their design that can be estimated through a quantity named blotter spot. We propose a comprehensive approach that combines machine learning techniques with visual analytics strategies in an interactive tool that supports domain experts’ decision-making. We evaluated the proposed models quantitatively and illustrated their benefits through a case study. Specifically, we analyzed a series of virtual polyisobutylene succinimide (PIBSI) molecules derived from a known reference substrate. Our best-performing probabilistic model was Bayesian Additive Regression Trees (BART), which achieved a mean absolute error of (Formula presented.) and a root mean square error of (Formula presented.), as estimated through 5-fold cross-validation. To facilitate future research, we have made the dataset, including the potential dispersants used for modeling, publicly available. Our approach can help accelerate the discovery of new oil and lubricant additives, and our interactive tool can aid domain experts in making informed decisions based on blotter spot and other key propertie