Off-line programming provides an essential link between CAD and CAM. The development of off-line programming
systems should result in greater use of robots and accelerate the implementation of flexible manufacturing systems (FMS). It also offers an alternative for complex automated production lines and should allow rapid response to changing product:process issues.
Off-line programming is, by definition, the technique of generating a robot program without using a real machine. It presents several advantages over the on-line method, some of which are described below:
* Programs are prepared without interruptions of robot operation, resulting in reduction of robot down time, which means flexibility and an increase in productivity.
* Removal of the programmer from the potentially dangerous environment, as most of the program development is executed away from the robot. Thus, the time during which the programmer is at risk from aberrant robot behaviour is reduced.
* There is a greater possibility for optimisation of the workspace layout and the planning of robot
tasks.
* New programs can include previously developed routines.
* Program changes can be incorporated quickly by substituting only the necessary part of the program.
* Signals from sensors can be incorporated into programs.
* Information from the environment (i.e. computerintegrated-manufacturing system; CAD:CAM systems can be incorporated into programs.
* It permits verification of the robot behaviour through graphical simulation and allows for the correction of any error in the program.
(G.C. Carvalho, M.L. Siqueira, S.C. Absi-Alfar, Off-line programming of flexible welding manufacturing cells, Journal of Materials Processing Technology 78 (1998), pp.24–28)
Total Quality Process Control (TQPC)
TQPC uses the quality methods developed by the quailty leaders to develop a system where the best quality methods are used for control of design, develpoment, and manufacturing processes. A well organized and documented total quality process control system must meet the following objevtives:
1. Positive customer orientation
2. Well defined and specific quality policies and objectives
3. Departments and personnel priented to achieving these objectives and carrying out the policies
4. Specific vendor control policies
5. Complate and identified part and process quality requirements
6. Full documentation of work instructions for operator use
7. Trained personnel with motivated and strong quality knowledge
8. Proactive preventative problem analysis program
9. Continuous real-time process control with closed-loop, self-adjusting control of process parameters, if not, operators capable for control
10. Periodic audits of process systems for compliance to specifications
(M. Joseph Gordon, Jr.,M. Joseph Gordon, Total Quality Process Control for Injection Molding, pp.15-29)
Clad Metal
A clad metal is one made of two dissimilar metals that have been pemanently bonded into a rolled
sheet or product. Ter process is not electroplating, and it uses no cement or binder. The dissimilar
metals are simply pressed together between the wringerlike rolls of a cladding machine. By
applying just the right pressure at just the right temperature for just the length of time, the process
bonds the metals together molecularly, and no amount of tension can pull them apart.
(G. H. Walts, Journal of Popular Science March (1949), pp.154-155)
Metal Disintegration Machining
In the metal disintegration machining process a constant voltage supply and a vibrating head
generate the machining pulses. Discharges take place when the electrode is close enough to
the workpiece before they make physical contact. Electronics in MDM are very simple compared
to EDM but the degree of control of MRR, SF and EW is lower. Resulting surface finish is rough.
This cut needed four operations to be finished. The cut made with the proposed EDM system, achieved the specified tolerance and the task of the operator was simply process surveillance.
(R. Casanueva, F. J. Azcondo, S. Bracho, Journal of Materials Processing Technology 149 (2004), pp.172–177)
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