Manufacturing Technology Today

R. Madhusudhan Rao ¹, R. Deepa ¹, V. Kavitha ¹, S. Usha ¹

Affiliations
1 Central Manufacturing Technology Institute (CMTI), Tumkur Road, Bengaluru, IN

Abstract

Structured Light Scanning (SLS) systems have become popular for their reliability and accuracy. In this work, Fringe Projection based SLS system has been developed. Usage of Multi-level Quality Guided Phase unwrapping algorithm for recovering the true phase map is presented; System calibration, along with the process of recovering depth from phase is explained. Finally measurement results are presented to reaffirm the fact that phase shifting technique along with quality guided spatial unwrapping can be used for fast, full field 3D-Scanning.

Keywords

Fringe Projection, 3-D Shape, Fringe Analysis, Unwrapping, Phase-Shifting.

Full Text

     

S. Usha ¹, P. V. Shashikumar ¹, G. C. Mohan Kumar ², S. Srikantharao ²

Affiliations
1 Central Manufacturing Technology Institute, Tumkur Road, Bangalore, IN
2 NITK, Suratkal, Mangalore, IN

Abstract

Semiconductor device fabrication process is the most sophisticated and complex manufacturing process. Advances in the manufacturing processes has brought down the feature size of gate to as low as 22 nm. Hence there is a great demand for process control of feature dimension below the resolution limit of visible wavelength microscopy. Lot of research has been focused on increasing the resolution of the metrology tools. We have adopted a novel optical technique that shows nanoscale measurement sensitivity using conventional optical microscopes. Here through-focus images are acquired at different focus positions. These focused and defocused images are used to build an intensity map whose signature reflects the target pattern. This technique is used to identify relative nanoscale change in dimension between two targets by finding the change in the signature of the intensity map.

Keywords

Through Focus Imaging, Focus Metric, Through Focus Signature, CD Metrology, Nano Metrology, Diffraction Limit.

Full Text

     

S. Usha ¹, P. V. Shashi Kumar ¹

Affiliations
1 Central Manufacturing Technology Institute, Bangalore, IN

Abstract

Conventional coordinate measuring machine posses problem for handling delicate components. Optical profile projectors require enormous time for manual cursor positioning to make measurements. A separate setup is called for inspecting the surface finish (microscope). These issues are addressed by a single setup using vision techniques for both precision measurements as well as to identify surface defects. This paper discusses about machine vision technique for metrology requirement and explain how ‘Vision for Metrology’ differs in terms of sensor requirement, lighting techniques, calibration methods and algorithm from a conventional vision system used for feature identification, recognition etc.

Keywords

Vision Metrology, Non-Contact Measurement.

Full Text

     

S. Usha ¹

Affiliations
1 Central Manufacturing Technology Institute, Bangalore, IN

Abstract

This last part of the series presents an overview of the commercially available existing optical 3D measurement systems.

Full Text

     

S. Usha ¹

Affiliations
1 Central Manufacturing Technology Institute, Bangalore, IN

Abstract

This part of the series presents on overview of the commercially available existing optical 3D measurement systems.

Full Text

     

S. Usha ¹

Affiliations
1 Central Manufacturing Technology Institute, Bangalore, IN

Abstract

This part of the series on Recent Trends in Machine Vision' deals with the performance assessment issues and techniques comprising calibration, sensors, occlusion, obscuration and softwares.

Full Text

     

S. Usha ¹

Affiliations
1 Central Manufacturing Technology Institute, Bangalore, IN

Abstract

This part of the series on Recent Trends in Machine Vision' in 'What is new in Technology' deals with the technological developments in 3D measurements in vision field such as BIRIS range sensor, micro projectors, digital micromirror devices, and their working principles in difficult environments.

Full Text

     

S. Usha ¹

Affiliations
1 Central Manufacturing Technology Institute, Bangalore, IN

Abstract

This part of the series on Recent Trends in Machine Vision' in 'What is new in Technology' deals with the Moire technique and laser radar 3-D imaging method or the speckle pattern sampling method in measurement applications, their advantages and limitations.

Full Text

     

S. Usha ¹

Affiliations
1 Central Manufacturing Technology Institute, Bangalore, IN

Abstract

This fourth part o f our special series on Recent Trends in Machine Vision' in 'What is new in Technology' deals with the structured light technique comprising laser interference method and fringe projection method and their resolution.

Full Text

     

S. Usha ¹

Affiliations
1 Central Manufacturing Technology Institute, Bangalore, IN

Abstract

This third part of our special series on Recent Trends in Machine Vision' in the 'What is new in Technology' talks about the principles of optical active triangulation & limitations of the approach and solutions.

Full Text

     

S. Usha ¹

Affiliations
1 Central Manufacturing Technology Institute, Bangalore, IN

Abstract

The machine vision technology has matured significantly over the past few years. It is emerging as a superior alternative to human labor in process and quality control and is extremely sought after to create lean and flexible manufacturing systems. With its ability to deliver high accuracy while ensuring throughput on the production line, vision systems also serve as efficient quality control tools. Emerging trends in the field of sensors, embedded systems, illumination methods, and camera and laser technology are expected to contribute immensely to the future growth of machine vision systems.

Full Text

     

S. Usha ¹

Affiliations
1 Central Manufacturing Technology Institute, Bangalore, IN

Abstract

This part of the series on 'Recent Trends in Machine Vision' in 'What is New in Technology' describes different measurements such as Interferometry, Stereophotogrammetry and Loser Tracking System.

Full Text

     

S. Usha ¹

Affiliations
1 Central Manufacturing Technology Institute, Bangalore, IN

Abstract

This second part of our special series on Recent Trends in Machine Vision’ in the ‘What is new in Technology’ talks about the active and passive vision measurement techniques.

Full Text

     

S. Usha ¹, R. V Patil ¹, B. Ramakumar ¹

Affiliations
1 Central Manufacturing Technology Institute, Bangalore-560022, IN

Abstract

Linear hydraulic actuators for critical applications, have to undergo very stringent qualification tests, to establish their suitability for the designed task. Endurance test is one of the important tests conducted on linear actuators, as a part of design qualification. The endurance test requirements are very stringent, and hence conducting the test manually is very tedious and time consuming. The paper describes a PC based Virtual instrumentation and controller developed for one such application.

Full Text

     

C. P. Mariadassou ¹, S. Usha ¹, D. R. Raghavendra ¹

Affiliations
1 Central Manufacturing Technology Institute, Bangalore-560022, IN

Abstract

Automatic Visual Inspection (AVI) is the process of using computer vision techniques for inspection. Due to increasing automation it is of late gaining widespread acceptance in the manufacturing industry. The crucial components of an AVI system are: (a) the camera, (b) the frame grabber, (c) the processor, (d) the vision processing software, (e) the lighting and (f) the interface between the AVI and the external system. While most of the components such as the camera, the frame grabber, processor and even the-interface software can be decided a priori the lighting and the vision software have to be determined on site. In this paper we shall be considering the problem of generating the vision software.

Full Text

     

M. K. Mayuresh ¹, S. Harsha ¹, S. Usha ¹

Affiliations
1 Central Manufacturing Technology Institute, Bengaluru, IN

Abstract

This article presents the development of thin-film temperature sensor with two different types of packaging techniques on silicon wafer. Platinum (Pt) thin film sensing element is designed and fabricated by MicroElectro-Mechanical Systems (MEMS) technology, based on photolithography, e-beam evaporation and liftoff techniques on silicon substrate for machine tools applications. SiO2 and Ti are used as insulation and adhesion layers respectively. The thickness of SiO2, Ti and Pt are in nanometers and coated using e-beam evaporation system. The electrical connections were established using Nickel (Ni) coated Copper (Cu) leads. Temperature sensor was extensively characterized using thermal cycling chamber and Fluke calibrator. We have observed 99.975% linearity and ± 0.50C accuracy for temperature range of -25 to 1800C. The temperature coefficient of resistance (TCR) or Alpha (α) was found to be 0.002335 / 0C after repetitive thermal cycling experiment. The sensor is packaged with two different techniques, epoxy packaging and stainless steel (SS) probe package. Two types of epoxies were used, one is electrically and thermally conductive and the other one is ceramic epoxy for isolation and protection. The response time of the sensor with epoxy packaging and SS packaging are 0.4 Sec and 3 Sec respectively. The response time of SS probe can be further reduced by using thin tubes.

Keywords

MEMS, Sensors, Temperature Sensor, Thin-Film, Platinum.

Full Text