Çağatay Taylan TAN 030070119 2nd week

FINITE ELEMENT ANALYSIS

Finite element analysis is one of the powerful techniques for not only design but also for manufacturing applications. Therefore, FEA has an important role in CIM.
Traditional approach to design analysis involves the application of classical or analytical
techniques. This approach has the following limitations:
i. Stresses and strains are obtained only at macro level. This may result in
inappropriate deployment of materials. Micro level information is necessary to
optimally allocate material to heavily stressed parts.
ii. Adequate information will not be available on critically stressed parts of the
components.
iii. It may be necessary to make several simplifications and assumptions to design
complex components and systems, if design analysis is carried out in the
conventional manner.
iv. Manual design is time consuming and prone to errors.
v. Design optimization is tedious and time consuming.
FEA is a convenient tool to analyze simple as well as complex structures. The use of
finite element analysis is not restricted to mechanical engineering systems alone. FEA finds
extensive application in electrical engineering, electronics engineering, micro electro mechanical systems, biomedical engineering etc. In manufacturing, FEA is used in simulation and optimization of manufacturing processes like casting, machining, plastic molding, forging, metal forming, heat treatment, welding etc. Structural, dynamic, thermal, magnetic potential and fluid flow problems can be handled with ease and accuracy using FEA.

(CAD/CAM/CIM 3.edition, P. Radhakrishnan, S. Subrahmanyan, V. Raju, p.189)

DATABASE (about CAD systems)

Many components either are standard components that are mass produced according to given design specifications ( such as bolts and gears) or are identical to parts used in previous designs.Modern CAD systems thus have built-in database-management system that allows designers to locate ,view ,and adopt parts from a stock part library.These parts can be modeled parametically to allow cost-effective updating of geometry.Some databases are available commercially with extensive parts libraries; many vendors make their part libraries available on the world wide web.

(Kalpakjian S., Schmid S.R.,Manufacturing engineering and technology, 5th Edition, p 1203)


CONTINUOUS SYSTEM

The product is assembled while moving at a constant speed on pallets or similar workpiece carriers.The parts to be assembled are brought to the product by various workheads, and their movements are synchronized with the continuous movement of the product.Typical applications of this system are in bottling and packaging plants although the method also has been used on mass-production lines for automobiles and appliances.

(Kalpakjian S., Schmid S.R.,Manufacturing engineering and technology, 5th Edition, p 1182)


ROBOTIC ASSEMBLY

Design guidelines for robotic assembly include the following additional considerations.
- Parts should be designed so that they can be gripped and manipulated by the same gripper ( end effector) of the robot.Such a design avoids the need for different grippers.Parts should be made available to the gripper in the proper orientation.
-Assembly that involves threaded fasteners ( bolts , nuts and screws) may be difficult for robots.One exception is the use of self threading screws for sheer metal, plastics, and wooden parts.Also, note that robots easily can handle snap fits, rivers, welds and adhasives.
The development of compliant end effectors and dexterous manipulators has made robotic assembly even more attractive.

(Kalpakjian S., Schmid S.R.,Manufacturing engineering and technology, 5th Edition, p 1185)