A novel force-based two-dimensional tool centre error identification method in single-point diamond turning

Although Single Point Diamond Turning (SPDT) can do pretty well in optical surfacing of large scale KDP crystal, both the surface accuracy and integrity are considerably high; meanwhile as the defects of micro-waveness and stress are inevitable, the laser-induced damage threshold of KDP optical elements after SPDT still cannot be satisfied. Because of the characters of deliquescent and water-soluble, the process of computer controlled Micro-nano deliquescence is attempted to remove the residual micro-waveness on KDP surface after SPDT. Based on the assumption of Preston and the characters of Micro-nano deliquescence, the model of material removal ratio is suggested, the dwell time for ascertained KDP surface is solved, the processing of computer controlled Micro-nano deliquescence is simulated and the processed surface condition on theory is obtained. Besides, the influences of different parameters on the surfacing efficiency and accuracy are analyzed. Finally, three polishing tracks are comparatively analyzed. The simulation results are quite important in guiding the experimental polishing of large scale KDP by computer controlled Micro-nano deliquescence

Download Full-text

Brittle-Ductile Transition and Nano-Surface Generation in Single-Point Diamond Turning of Single-Crystal Germanium

SSRN Electronic Journal ◽

10.2139/ssrn.3963571 ◽

2021 ◽

Author(s):

Guoqing Zhang ◽

Yanbing Chen ◽

Junhong Han ◽

Jianpeng Wang

Keyword(s):

Single Crystal ◽

Single Point ◽

Diamond Turning ◽

Surface Generation ◽

Brittle Ductile Transition

Download Full-text

A Conformable Two-Dimensional Resistance Temperature Detector for Measuring Average Skin Temperature

Journal of Medical Devices ◽

10.1115/1.4051442 ◽

2021 ◽

Author(s):

Laura Namisnak ◽

Sepideh Khoshnevis ◽

Kenneth R. Diller

Keyword(s):

Surface Temperature ◽

Skin Temperature ◽

Infrared Thermography ◽

Single Point ◽

Wearable Sensors ◽

Two Dimensional ◽

Nonuniform Temperature ◽

Resistance Temperature Detector ◽

Temperature Detector ◽

Average Skin

Abstract Various medical procedures are accomplished by manipulating skin temperature in a nonuniform pattern. Skin temperature monitoring is essential to assess conformance to protocol specifications and to prevent thermal injury. Existing solutions for skin temperature monitoring include single point sensors, such as thermocouples, and two-dimensional methods of sensing surface temperature, such as infrared thermography, and wearable technology. Single point sensors cannot detect the average temperature and consequently their measurements cannot be representative of average surface temperature in a nonuniform temperature field. Infrared thermography requires optical access, and wearable sensors may require complex manufacturing processes and impede the heat exchange with a source by introducing a layer of insulation. Our solution is a two-dimensional resistance temperature detector (2D RTD) created by knitting copper magnet wire into custom shapes. The 2D RTDs were calibrated, compared to one-dimensional sensors and wearable sensors, and analyzed for hysteresis, repeatability, and surface area conformation. Resistance and temperature were correlated with an R2 of 0.99. The 2D RTD proved to be a superior device for measuring average skin temperature exposed to a nonuniform temperature boundary in the absence of optical access such as when a full body thermal control garment is worn.

Download Full-text

Tool interference at workpiece centre in single-point diamond turning

International Journal of Mechanical Sciences ◽

10.1016/j.ijmecsci.2018.10.057 ◽

2019 ◽

Vol 151 ◽

pp. 1-12 ◽

Cited By ~ 5

Author(s):

Guoqing Zhang ◽

Yuqi Dai ◽

Suet To ◽

Xiaoyu Wu ◽

Yan Lou

Keyword(s):

Single Point ◽

Diamond Turning ◽

Tool Interference

Download Full-text

Rapid Measurement and Identification Method for the Geometric Errors of CNC Machine Tools

Applied Sciences ◽

10.3390/app9132701 ◽

2019 ◽

Vol 9 (13) ◽

pp. 2701 ◽

Cited By ~ 3

Author(s):

Li ◽

Yang ◽

Gao ◽

Su ◽

Wei ◽

...

Keyword(s):

Error Compensation ◽

Machine Tools ◽

Degrees Of Freedom ◽

Cnc Machine Tools ◽

Geometric Errors ◽

Two Dimensional ◽

Cnc Machine ◽

Angle Sensor ◽

Identification Method ◽

Measuring Machine

Error compensation technology offers a significant means for improving the geometric accuracy of CNC machine tools (MTs) as well as extending their service life. Measurement and identification are important prerequisites for error compensation. In this study, a measurement system, mainly composed of a self-developed micro-angle sensor and an L-shape standard piece, is proposed. Meanwhile, a stepwise identification method, based on an integrated error model, is established. In one measurement, four degrees-of-freedom errors, including two-dimensional displacement and two-dimensional angle of a linear guideway, can be obtained. Furthermore, in accordance with the stepwise identification method, the L-shape standard piece is placed in three different planes, so that the measurement and identification of all 21 geometric errors can be implemented. An experiment is carried out on a coordinate measuring machine (CMM) to verify the system. The residual error of the angle error, translation error and squareness error are 1.5″, 2 μm and 3.37″, respectively, and these are compared to the values detected by a Renishaw laser interferometer.

Download Full-text