Cloud-based Design and Manufacturing (CBDM) has emerged as an enabler for product realization by integrating various service-based models. However, the existing framework does not thoroughly support the innovation ecosystem from concept to product realization by formally addressing economic challenges and human skillset requirements. Our work considers the augmentation of the Design-as-a-Service (DaaS) model into the existing CBDM framework for enabling systematic product innovations. The DaaS model proposes to connect skilled human resources with enterprises interested in transforming an idea into a product or solution through the CBDM framework. The model presents an approach for integrating human resources with various CBDM elements and end-users through a service-based model. It is established that the DaaS has the potential for rapid and economical product discovery and can be readily accessible to SMEs or independent individuals.
Contrived Tool Wear Methodology
The stochastic nature of the tool wear makes it difficult to model and requires a significant number of cutting tests and machining of a large volume of material that incurs high cost and time. To avoid such time-consuming and cost-intensive cutting tests, the methodology is developed to generate tool wear artificially using a grinding process. The tools are worn by taking several passes over a grinding wheel in a controlled environment. The performance of contrived and naturally worn tools is compared by analyzing various parameters such as process force, wear topography and chip formation, which shows a good agreement. Also, it is realized that the contrived wear method enables a consistent starting point while studying any wear stage of the worn-out tool, thereby decoupling the stochastic nature of tool wear.
Evolution of Tool Wear in Machining of Inconel 718
In recent years, machine vision techniques are becoming predominant for various manufacturing applications, such as identifying machine setup abnormalities, tool status monitoring, and machined surface analysis. An image recognition-based method is developed to measure the flank wear width/area during trochoidal milling of Inconel 718. The proposed method is implemented as an automated computational program, and a series of experiments are performed to analyze the progression of the tool flank wear area over the volume of material removed. The developed image processing method is able to evaluate the flank wear width/area accurately and efficiently.
The concept of stochastic machining aims to introduce stochastic nature to the toolpath. The toolpath strategy involves random movement of the tool over the surface. It is hypothesized that the random motion of the tool avoids resonance by continuously varying the direction of cutting force and thereby reduces chatter. Also, the tool often passes over already machined regions of the workpiece and enables rapid dissipation of heat. The stochastic toolpath strategy devised herein is applied to generate toolpath for 3-axis ball-end milling of 2-Dimensional (2D) and free form surfaces.
Machining of Thin-walled Components
Predictive Framework for Estimation of Geometric Tolerance
A computational framework is realized to estimate static tool and workpiece deflection-induced geometric tolerances during end milling of thin-walled straight and constant curvature or circular components. The framework requires systematic integration of several computational models to predict cutting forces, estimate coordinates representing distorted machined surface due to the tool and workpiece deflections, and a mechanism to transform distorted coordinates into geometric tolerances for straight and circular thin-walled components.
Control of Geometric Tolerances
The rigidity of the thin-walled component varies considerably with the change of workpiece curvature and reduces as machining progresses due to material removal. This variation leads to a violation of geometric tolerances envisaged by the designer. The research work devised a Rigidity Regulation Approach (RRA) to obtain the semifinished geometry at the end of roughing operation. The finish cutting sequence is performed subsequently on the geometry for achieving optimal geometric tolerances.