Mathematical approach for optimal machining fixture layout and clamping forces

Abstract

Machining fixtures are used to locate and constrain a workpiece during machining operation. An ideal fixture design exhibits minimal moment while machining. The purpose of this work is to design an optimum fixture layout in order to reduce the maximum elastic deformation of the workpiece by reducing the moment caused by the clamping and machining forces acting on the workpiece while machining. This can be achieved by selecting the optimal locations of fixturing elements such as locators and clamps. The objective equations are formed based on equilibrium conditions and are solved for minimum value of clamping force condition for various fixture layouts. The required equations are formulated based on the equilibrium conditions of forces, moments and stick/slip conditions. Then these equations are solved for several fixture layouts and the corresponding clamping force sets are found. Thus the clamping forces satisfying constraints, along with its respective layout are solved for deformation values using ANSYS software. Layout providing minimum deformation value is selected as the optimal one.

Keywords:

• Fixture layout
• clamping force
• finite element analysis
• harmonic analysis

Additional information

Notes on contributors

S Selvakumar

S.Selvakumar serves as Assistant Professor in Mechanical Engineering Department at Kongu Engineering College, Erode, India. He holds Master of Engineering in Computer Aided Design from Periyar University and Bachelor degree in Mechanical Engineering from University of Madras. He is a member of the Indian Society of Technical Education. His research interests are in the areas of fixture design and optimisation.

K P Arulshri

Dr K. P. Arulshri is a Professor in Mechanical Engineering. He holds a PhD degree in Smart Materials, Master of Engineering in Engineering Design and Bachelor degree in Mechanical Engineering. He currently serves as Principal in KPR Institute of Engineering and Technology, Coimbatore, India. His research interests are in the areas of smart materials and optimisation.

K P Padmanaban

Dr K. P. Padmanaban is a Professor in Mechanical Engineering. He holds a PhD degree in Optimum Fixture Design and currently serves as Principal in SBM College of Engineering and Technology, Dindigul, India. He has published more than 15 research papers in international journals, and about 20 research papers in the national and international conferences. His research interests are in the areas of fixture design and optimisation.

K S K Sasikumar

K. S. K. Sasikumar serves as Assistant Professor in Mechanical Engineering Department at Kongu Engineering College, Erode, India. He holds a Master of Engineering in Engineering Design and Bachelor of Engineering in Mechanical Engineering from the Bharathiyar University. His research interests are in the areas of vibration and vibration absorbers.