Thermal error reduction based on thermodynamics structure optimization method for an ultra-precision machine tool

Zha

J Braz. Soc. Mech. Sci. Eng.

2020

Based on the hardness inspiration of the tortoise structure, this study analyzes the innovative application of the parts of ultra-precision machine tools. Aiming at the problems of machining accuracy, efficiency, and machine cost of ultra-precision machine tools, an innovative design and analysis of chuck of ultra-precision machine tools based on carbon fiber-reinforced polymer and its application to turtle shell structure is proposed. Firstly, the G-element model of carbon fiber composites is deduced and analyzed by layered experiments. Secondly, the original parts of ultra-precision machine tool are simulated and analyzed, and the main sixth-order modal of carbon fiber turtle shell structure is deduced. Finally, the structural parameters of carbon fiber composite "turtle shell" were applied to the surface of chuck claw of ultra-precision machine tool, and the results were compared and analyzed. The results show that the maximum displacements of the chuck are all located at the front of the chuck and the maximum displacements and stresses of the chuck are smaller than those of the original chuck. The maximum stress is the most obvious, the difference is about 240.27 MPa, and the first-order mode increases by 23.4% compared with the original mode. The overall relative mass was reduced by 61.2%.

“…Finally, the sixth-order main modes of the chuck mechanical system of the high-speed precision grinder are obtained:{A (1) }, {A (2) }, {A (3) }, {A (4) }, {A (5) } 和 A (6) 。…”

Section: Analysis Of Structural Components Of Turtle Shellmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Study on chuck performance of ultra-precision machine tool based on CFRP pair bionic structure

Zha

J Braz. Soc. Mech. Sci. Eng.

2020

“…Based on the multi-body system theory, Liu et al [9] established a machining error model for a three-axis ultraprecision lathe to study the influence of geometric errors of machine tool configuration. Sun et al also developed a thermodynamics-based structure optimization method to decrease the thermal displacements during machining process [10]. Additionally, Nagayama and Yan used a white light interferometer to measure the tool contour error and compensated it in generated tool paths [11].…”

Section: Introductionmentioning

confidence: 99%

An Efficient Ultraprecision Machining System Automating Setting Operations of Roughly Machined Workpiece

Nakamoto

Takeuchi

2021

JMMP

Ultraprecision machining is required in many advanced fields. To create precise parts for realizing their high performance, the whole machining process is usually conducted on the same ultraprecision machine tool to avoid setting errors by reducing setting operations. However, feed rate is relatively slow and machining efficiency is not so high compared to ordinary machine tools. Thus, the study aims to develop an efficient ultraprecision machining system including an industrial robot to avoid manual setting and to automate the setting operations. In this system, ultraprecision machining is conducted for the workpiece having a shape near the target shape, which is beforehand prepared by ordinary machine tools and is located on the machine table by means of an industrial robot. Since the setting errors of the roughly machined workpiece deteriorate machining accuracy, the differences from the ideal position and attitude are detected with a contact type of on-machine measurement device. Numerical control (NC) data is finally modified to compensate the identified workpiece setting errors to machine the target shape on an ultraprecision machine tool. From the experimental results, it is confirmed that the proposed system has the possibility to reduce time required in ultraprecision machining to create precise parts with high efficiency.

J Braz. Soc. Mech. Sci. Eng.

“…The methods of constructing a thermal error model of a machine tool spindle system mainly include analytic modeling and empirical modeling [12]. Analytical modeling was used to analyze a machine tool spindle structure based on the heat conductivity theory, resolve the temperature field through a heat conductivity analytic equation and obtain the thermal deformation via the mechanical principle [14][15][16]. However, the component boundary conditions were complex, resulting in analytic model difficulties and unsuitability for engineering applications.…”

Section: Introductionmentioning

confidence: 99%

Thermal error modeling of CNC milling machining spindle based on an adaptive chaos particle swarm optimization algorithm

Yue

Guo

et al. 2020

The thermal error of machine tool spindle system has become an important factor affecting machining accuracy. Measurement experiments of a 3-axis vertical milling machine spindle system were conducted to assess temperature fields and thermal errors. The fuzzy clustering and gray correlation algorithms were adopted to cluster the temperature measuring points and identify the temperature-sensitive points. Based on the adaptive chaos particle swarm optimization algorithm, thermal error models were established in the axial and radial directions for the spindle system, and the compensation effects were evaluated by the workpiece machining accuracy. The results showed that the number of temperature measuring points was reduced from 12 to 6. The residual range of measured and predicted thermal error values in the axial direction was 6.17-4.19 μm, and the modeling accuracy was 95.53%. The radial residual ranges were − 2.75-3.05 μm and − 2.10-2.15 μm, and the modeling accuracies were 90.74% and 91.10%, respectively. The model compensation effect was demonstrated remarkably in the verification experiments. The thermal error models showed high prediction precision, could improve machining accuracy and had strong engineering application value.