Sajid Ullah Butt
Sajid completed his Undergraduate degree from NWFP University of Engineering and Technology, Peshawar, Pakistan and Masters of Science from Arts et Metiers, ParisTech, Metz, France. He joined us on September 11, 2022 and is currently working as a visiting professor in our team.
My Work
Research interests:
Advanced Manufacturing, Optimization, Analytical modeling.
Research Summary:
High-level research area
Improve the machined part quality by predicting and rectifying the positioning errors that may be caused due to clamping and machining forces
Specific problems and challenges
When the part is located and clamped on the machine for machining, its location varies from the original position due to external (machining and clamping) forces. The deformation depends upon the magnitude of forces and moments as well as the elasticity of the clamps, locators, and workpieces. If we are able to calculate the displacement, it can be rectified.
Proposed solution
A Lagrangian formulation-based analytical model predicted the workpiece's positioning error (displacement) under the application of external forces.
Methodology
An analytical model was developed which, by assuming all locators, clamps, and workpieces (at contact with locators and clamps) to be elastic, calculated the potential energy of all the elastic members and work done by all the external forces. All the deformations were calculated in terms of the virtual displacement of the workpiece. Lagrangian formulation gave the required unknowns i.e. displacement of the workpiece under external load.
To simulate the machining process, the single-point load was replaced with multi-point loads, and using GA the optimized location of all six locators was calculated based on the minimum displacement of the workpiece at each loading point. The results were verified using ANSYS.
Results and deliverables so far
The new location showed better positioning and lesser displacement under the load.