An Investigation on High-Resolution Temperature Measurement in Precision Fly-Cutting

The loads acting on a workpiece during machining processes determine the modification of the surface of the final workpiece and, thus, its functional properties. In this work, a method that uses thermocouples to measure the temperature in precision fly-cutting machining with high spatial and temporal resolution is presented. Experiments were conducted for various materials and machining parameters. We compare experimental measurement data with results from modern and advanced machining process simulation and find a good match between experimental and simulation results. Therefore, the simulation is validated by experimental data and can be used to calculate realistic internal loads of machining processes.

Error Investigation for Free Form Surfaces in Bezier Techniques

Surface modeling utilizing Bezier technique is one of the more important tool in computer aided geometric design (CAD). The aim of this work is to design and implement multi-patches Bezier free-form surface. The technique has an effective contribution in technology domains and in ships, aircrafts, and cars industry, moreover for its wide utilization in making the molds. This work is includes the synthesis of these patches in a method that is allow the participation of these control point for the merge of the patches, and the confluence of patches at similar degree sides due to degree variation per patch. The model has been implemented to represent the surface. The interior data of the desired surfaces designed by MATLAB software have been transformed to UG-NX8 software to get the machining process simulation and G-code programs for the model, as well as a virtual machining process has been simulated to show the machining pitfalls, using CIMCO edit software. The sample has been machined using 3-axis vertical CNC machine. Finally, the sample has been measured using (CMM inspection) and it’s found that the average of error (0.144 mm).

Machining Process Simulation to Find NC Program and Cutting Time

To produce the bulk products in metal industry, tool path and cutting time are necessary to predict the amount of product that can be produced within a certain time (throughout the tool life). The ways used so far are to sacrifice some of the product as an experimental material. Using such a method will cause many losses, including much time to machining product by trial and error will cause the waste materials. To solve problem above, this paper described solution to get the accuracy of tool path and cutting time. The solution offered is to use software to simulate the machining process, so that losses due to time and wasted materials can be resolved.

Cutter-workpiece engagement determination for general milling using triangle mesh modeling

Cutter-workpiece engagement (CWE) is the instantaneous contact geometry between the cutter and the in-process workpiece during machining. It plays an important role in machining process simulation and directly affects the calculation of the predicted cutting forces and torques. The difficulty and challenge of CWE determination come from the complexity due to the changing geometry of in-process workpiece and the curved tool path of cutter movement, especially for multi-axis milling. This paper presents a new method to determine the CWE for general milling processes. To fulfill the requirement of generality, which means for any cutter type, any in-process workpiece shape, and any tool path even with self-intersections, all the associated geometries are to be modeled as triangle meshes. The involved triangle-to-triangle intersection calculations are carried out by an effective method in order to realize the multiple subtraction Boolean operations between the tool and the workpiece mesh models and to determine the CWE. The presented method has been validated by a series of case studies of increasing machining complexity to demonstrate its applicability to general milling processes. Highlights A new method to determine cutter-workpiece engagement geometry in milling. Applicable to general milling processes: all cutter types, in-process workpiece shapes and tool paths containing even self-intersections. Results validated by a series of case studies of increasing machining complexity.

Research on Technologies of Augmented Reality for CNC Machining Process Simulation

Based on Virtual Numerical Control machining system (VNC), a new method of Augmented Numerical Control machining system (ANC) which aims at the realization of NC machining process simulation in real machining environment is put forward. The System inputs continuous video images of real NC processing environment through camera to identify and locate the major machining and positioning parts of real machine in the image stream. And the virtual parts of VNC will be matched to the corresponding real ones of real machining system to achieve the registration of ANC. The NC system drives the virtual machining models for processing through a real machine. On the other hand, the actual running information of CNC machine are imported into the ANC system to drive some models of process variables such as cutting force, material removal rate, chip shape, tool temperature, cutting tool wear. ANC provides the platform to integrate the geometry and physical simulation based on actual information from real CNC machining environment.

Application Analysis of Virtual Simulation Technology in NC Machining

With the help of the computer simulation technology, the virtual machining simulation system of NC machine tool was built based on the integrated simulation module of the UG NX software. Through setting the NC machine parameter of the virtual machining system, the machining process simulation of the typical parts in virtual environment was completed, which implements the collision and interference checking in the process of NC machining and verifies the correctness of NC programs. Finally, the simulation results prove that the assembly modeling method of virtual simulation system for the NC machining is feasible, and the simulation of machining process can effectively determine the mutual interference problem of the machining system, which lays the foundation for effectively preventing the collision accident.