Informatics Publishing Limited

V. Vidyaa ¹, Gladys Sheba Chandrakumari ², S. Hosimin Thilagar ³, M. Kanthababu ², R. Balasubramanian ⁴, V. K. Suri ⁴

Affiliations
1 Dept. of Mechanical Engg., Jawahar Engg. College, Chennai, IN
2 Dept. of Manufacturing Engg., Anna University, Chennai, IN
3 Dept. of Electrical and Electronics Engg., Anna University, Chennai, IN
4 Precision Engg. Division, Bhabha Atomic Research Center, Mumbai, IN

Abstract

Grippers are used to pick, hold and place macro/micro-components, which are widely used in the field of assembly. In this work, for the first time an electro-thermal gripper (collet) is designed and analysed using two thermal actuator structures with reverse currents in order to reduce the out-of-plane actuation for holding micro-components in a narrow range of sizes between 100 μm to 1000 μm. The electro-thermal gripper is designed and analyzed using Comsol Multiphysics Design and Analysis Software. The materials considered for the electro-thermal gripper are alluminium and steel. From the analysis, it is observed that in the case of alluminium electro-thermal gripper at 0.1 V, the in-plane displacement is found to be 22 μm and the out-of-plane displacement is found to be 0.1 μm. In the case of steel electro-thermal gripper at 0.1V, the in-plane displacement is found to be 0.1 μm and out-of-plane displacement is found to be 0.00005 μm. It is observed that alluminium results in better displacement compared to steel.

Keywords

Microgripper, Electro-Thermal Gripper, Microactuator, Comsol Multiphysics.

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M Prakash , P. Hariharan , M. Kanthababu

Abstract

Recent scenario and technology moving rapidly towards the development of micro- devices in the millimeter to sub-millimeter range. Micro manufacturing plays an important role in recent development and application of miniaturized products. One of the tool based micro manufacturing process known as microendmilling has become an established process for manufacturing micro components in metal and metal alloys.  For the complicated contouring applications, manual part programming becomes cumbersome and is prone to errors. In this work an attempt has been made to overcome these problems by use of specially designed software. This software automatically generates CNC part programs, when the part geometry is defined. It reduces the time consumed by the operator to enter the program manually and also eliminate the programming errors. This software automate the computer numerical control (CNC) programming for micro-endmilling machine to perform point to point operation, straight cut operation and contouring operation. The development of this technique leads to reduce the cost of fabrication for the most of the microstructures and at the same time reduces the product time to market. Optimized tool path for pocket milling operation are also identified as parallel plane method based on surface roughness and machining time.

Keywords

Computer Numerical Control (CNC), Micro-endmilling, Part Programme, Tool Path, Surface Roughness

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V. Mohankumar ¹, M. Kanthababu ¹

Affiliations
1 Department of Manufacturing Engineering, College of Engineering, Guindy, Anna University, Chennai, IN

Abstract

In the present investigations, an attempt is made to study the Abrasive waterjet Machining (AWJM) aspects of Metal Matrix Composites (MMCs) consist of aluminium alloy (Al 7075) reinforced with boron carbide (B₄C) in various proportion such as 5%, 10% and 15% by weight for achieving maximum depth of cut. Experiments were conducted on the trapezoidal shaped specimens in the unreinforced Al 7075 and MMCs by varying the input process parameters such as abrasive mesh sizes, abrasive flow rate, waterjet pressure and traverse rate. The experiments were carried out based on Response Surface Methodology (RSM) using Box Behnken method. The results were analyzed using response graphs. From the analysis, it is observed low abrasive mesh size, high abrasive flow rate, high waterjet pressure and low traverse rate are resulted in higher DOC in the unreinforced Al 7075 as well as MMCs.

Keywords

Abrasive Waterjet Machining, Metal Matrix Composites, Aluminium Alloy 7075, Boron Carbide, Response Surface Methodology.

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