Molecular dynamics (MD) simulation and finite element (FE) method are two popular numerical techniques for the simulation of machining processes. The two methods have their own strengths and limitations. The MD simulation can cover the phenomena occurring at nanometric scale lengths but limited by the computational cost and capacity, while FE method is suitable for modelling the meso to macro scale machining and for simulating macro parameters such as the temperature in a cutting zone, the stress/strain distribution and cutting forces, etc. With the successful application of multiscale simulations in many research fields, the application to simulate machining processes is emerging particularly in relation to the machined surface generation and integrity formation, i.e. the machined surface roughness, residual stress, microhardness, microstructure and fatigue.Based on the Quasicontinuum (QC) method, the multiscale simulation of nanometric cutting has been proposed. Cutting simulations are performed on single crystal aluminium to investigate the chip formation, generation and propagation of the material dislocation during the cutting process. In addition, the effect of the tool rake angle on cutting force and internal stress under the workpiece surface is investigated. The cutting force and internal stress in the workpiece material decrease with the increase of the rake angle. Finally, to ease and speed up multiscale modelling and simulation steps, a computing efficient MATLAB-based program has been developed, which facilitates the geometrical cutting modelling, simulation conditions, implementation of simulation and results analysis within a unified integrated virtual simulation environment.

Molecular dynamics (MD) simulation and finite element (FE) method have been successfully applied in the simulation of the machining process, but the two methods have their own limitations. For example, the MD simulation can only explain the phenomena occurring at nanometric scale because of the computational cost and nanoscale, while the FE method is suited to model meso-macroscale machining and to simulate macro parameters such as the temperature in cutting zone, the stress/strain distribution, and cutting forces. With the successful application of multiscale simulation in many research fields, the multiscale simulation of the machining process is becoming possible in relation to the machined surface generation including the surface roughness, residual stress, microhardness, microstructure, and fatigue. Based on the quasicontinuum (QC) method, this paper presents the multiscale simulation of nanometric cutting of crystal copper to demonstrate that a combined MD—FE technique can be applied to a multiscale simulation of the machining process. The study shows that the multiscale simulation is feasible, not withstanding that there is still more work needing to be done to make the multiscale simulation more practical.

Advanced virtual coordinate-measuring machines (CMMs) (AVCMMs) have recently been developed at Brunel University, which provide vivid graphical representation and powerful simulation of CMM operations, together with Monte-Carlo-based uncertainty evaluation. In an integrated virtual environment, the user can plan an inspection strategy for a given task, carry out virtual measurements, and evaluate the uncertainty associated with the measurement results, all without the need of using a physical machine. The obtained estimate of uncertainty can serve as a rapid feedback for the user to optimize the inspection plan in the AVCMM before actual measurements or as an evaluation of the measurement results performed. This paper details the methodology, design, and implementation of the AVCMM system, including CMM modeling, probe contact and collision detection, error modeling and simulation, and uncertainty evaluation. This paper further reports experimental results for the testing of the AVCMM.

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