Automation in manufacturing

Boucher, T. O. (1996), Computer Automation in Manufacturing An Introduction, Chapman Htill,... 

The addition of computers and automation in manufacturing in the last decades of the twentieth century significantly boosted production and improved product quality. These improvements made things such as your video game possible, not to mention clothing, costume jewelry, contact lenses, and life-saving medical equipment. 

The primary advantages of automation in manufacturing include lower costs for the consumer and better quality products (Figure 18-12). Automation allows a company to produce more products in less time and with fewer mistakes. In the past, parts or products that were not made correctly were a large expense for a company. These parts often became scrap waste. 

Ultrasonic head forming and welding is a fast assembly technique. It is a very rapid operation of about 2 seconds or less and lends itself to full automation. In this process high-frequency vibrations and pressure are applied to the products to be joined, heat is generated at the plastic causing it to flow, and, when the vibrations cease, the melt solidifies. The heart of the ultrasonic system is the horn, which is made of a metal that can be carefully tuned to the frequency of the system. The manufacture of the horn and its shape is normally developed by the manufacturer of the equipment. The results from this operation are not only economical, but also most satisfactory from a quality control standpoint. 

Continuous analysis offers another very useful possibility of completely automated chemical control, especially in manufacturing processes, but also in analytical processes such as separational flow techniques where the analytical measurement proper acts as a sensor, usually called the detector. As long as a physical or physico-chemical constant yields a sufficiently accurate and specific... 

In 1976, Radiometer61 presented for the first time a microprocessor-controlled titration system. Since then, the microprocessor has been used preferentially and as a fully integrated part (in line) in electroanalytical instruments as a replacement for the on-line microcomputer used before. Bos62 gave a comprehensive description of the set-up and newer developments with microprocessors in relation to microcomputers and indicated what they can do in laboratory automation. Many manufacturers are now offering versatile microprocessor-controlled titrators such as the Mettler DL 40 and DL 40 RC MemoTitrators, the Metrohm E 636 Titroprocessor and the Radiometer MTS 800 multi-titration system. Since Mettler were the first to introduce microprocessor-controlled titrators with their Model DK 25, which could be extended to a fully automated series analysis via the ST 80/ST 801 sample transport and lift together with the CT 21/CT211 identification system, we shall pay most attention to the new Mettler MemoTitrators, followed by additional remarks on the Metrohm and Radiometer apparatus. 

Any decision to establish automated or robotic systems must carefully consider prerequisites such as the annual numbers of samples to be processed to achieve an acceptable cost-to-benefit ratio. Late phase development stability studies may benefit from fully automated systems based on the enormous numbers of samples to be analyzed for each stability time point. The use of automated systems in manufacturing quality control is now required due to the sheer number of samples to be... 

Broth fills should be earried out under conditions that are representative of those during normal operation. A deviation from routine processes should only be in the direction of presenting a higher rather than a lower challenge to the proeess. Due to the level of automation of BPS teehnology, it is extremely diffieult to take extra care in order to reduee the ehanee of container contamination during a broth fill, and results are therefore not as operator dependent as other less automated aseptie manufacturing processes. 

In the past, laboratories have justified the initial investment in dedicated automation on the basis of the large number of identical, repetitive operations carried out. Fixed or dedicated automation is utihzed for large quantities of standard procedures, such as those found in manufacturing environments or in clinical laboratories. Fixed automation follows a predetermined sequence of steps to perform a defined procedure although efficient, it can only perform one repetitive procedure. Robotics, however, can provide flexible automation to meet the changing needs typical of quality control and research laboratories. Flexible automation is programmed by individual users to perform multiple procedures, and can be quickly reprogrammed to accommodate new or revised procedures. In these situations, a careful assessment of the software overhead must be made before a decision to purchase is made. 

The instructions embedded in computer program(s) either provide information on what the operators are supposed to do, or information on how the equipment or processes are intended to function. For example, for manufacturing operations, the batch production and control records may provide procedures, controls, instructions, specifications, and precautions to be followed when using computer systems. These programs may also contain control data for product formulation, batch size, yields, and automated in-process sampling/testing procedures. 

Speed of Analysis. The speed with which many immunochemical analyses can be completed illustrates a major advantage of immunochemical procedures. Immunochemical assays are most time and cost effective when the sample load is large. Parker (4) estimated that a single technician could perform 100-5000 radioimmunoassays per day with little or no assay automation in comparison to 20-40 GLC assays (3). Numerous inexpensive systems are available to decrease analysis time. These systems may include solid phase separation techniques, automatic dispensers, test tube racks which will fit directly into a centrifuge and/or scintillation counter, and data handling systems. Alternatively, there are fully automated systems based on RIA or ELISA which require very little operator attention and which handle 25-240 samples/hr. Gochman and Bowie (81) have outlined the basis of operation and summarized the features of automated RIA systems and extensive literature is available from the manufacturers. 

Applied substrates require homogeneous and planar surfaces. Planar supports allow accurate scanning and imaging, which rely on a uniform detection distance between the microarray surface and the optical device. Planar solid support materials tend to be impermeable to liquids, allowing for a small feature size and keeping the hybridization volume to a minimum. Flat substrates are amenable to automated manufacture, providing an accurate distance from photo masks, pins, ink-jet nozzles and other manufacturing implements. The flatness affords automation, an increased precision in manufacture, and detection and impermeability. Table 1 shows frequently used support materials... 

Robert Fretz joined F. Hoffmann-Fa Roche more than 30 years ago as a chemical engineer. He is presently responsible for Process Automation in all chemical and galenical manufacturing sites and leads the corporate Mamrfacturing Execution systems program. Mr. Fretz has broad international experience in all levels of control/automation projects from instrumentation to the enterprise level. Many of these projects included computerized system validation. He co-authored the Hoffmann-Fa Roche corporate guideline on Process Automation Qualification. 

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