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Chapter 17 
AUTOMATED ASSEMBLY SYSTEMS 
REVIEW QUESTIONS 
17.1 Name three of the four conditions under which automated assembly technology should be considered. 
Answer: The four conditions named in the text are (1) high product demand, so that millions of units are 
produced, (2) stable product design, because design changes require tooling changes in the assembly system, (3) 
the assembly consists of no more than a limited number of components, say around a dozen or fewer, and (4) the 
product is designed for automated assembly. 
17.2 What are the four automated assembly system configurations listed in the text? 
Answer: The four configurations are (a) in-line assembly machine, (b) dial-type assembly machine, (c) carousel 
assembly system, and (d) single-station assembly machine. 
17.3 What are the typical hardware components of a workstation parts delivery system? 
Answer: The typical components are (1) hopper, (2) parts feeder, (3) selector and/or orientor, (4) feed track, and 
(5) escapement and placement device. 
17.4 What is a programmable parts feeder? 
Answer: As defined in the text, a programmable parts feeder is a feeder that is capable of feeding components of 
varying geometries with only a few minutes required to make the adjustments (change the program) for the 
differences. 
17.5 Name six typical products that are made by automated assembly. 
Answer: The products identified in the text are alarm clocks, audio tape cassettes, ball bearings, ball point 
pens, cigarette lighters, computer disks, electrical plugs and sockets, fuel injectors, gear boxes, light bulbs, locks, 
mechanical pens and pencils, printed circuit board assemblies, pumps for household appliances, small electric 
motors, spark plugs, video tape cassettes, and wrist watches. 
17.6 Considering the assembly machine as a game of chance, what are the three possible events that might occur when 
the feed mechanism attempts to feed the next component to the assembly workhead at a given workstation in a 
multi-station system? 
Answer: The three possible events are (1) the component is defective and causes a station jam, (2) the 
component is defective but does not cause a station jam, and (3) the component is not defective. 
17.7 Name some of the important performance measures for an automated assembly system. 
Answer: The performance measures considered in the text include yield (proportion of assemblies produced with 
no defective components), production rate, proportion uptime (a.k.a. line efficiency), and unit cost per assembly. 
17.8 Why is the production rate inherently lower on a single-station assembly system than on a multi-station assembly 
system? 
Answer: Because all of the work elements are performed sequentially at one station in the single station system, 
whereas the elements are performed simultaneously at multiple workstations in a multi-station system. 
17.9 What are two reasons for the existence of partially automated production lines? 
Answer: The two reasons given in the text are (1) automation is introduced gradually on an existing manual line 
and (2) certain manual operations are too difficult or too costly to automate. 
17.10 What are the effects of poor quality parts, as represented by the fraction defect rate, on the performance of an 
automated assembly system? 
Answer: The two effects given in the text are (1) jams at stations that stop the entire assembly system to 
adversely affect production rate, uptime proportion, and cost per unit produced; or (2) assembly of defective 
parts in the product to adversely affect yield of good assemblies and product cost. 
17.11 Why are storage buffers used on partially automated production lines? 
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Answer: Storage buffers are used on partially automated production lines to isolate the manual stations from the 
breakdowns of the automated stations. Thus, workers do not have to stop working when an automated station 
breaks down.