METHODS ENGINEERING:GATHERING / ORGANIZING INFORMATION
GATHERING / ORGANIZING INFORMATION
This section will discuss What to study (Pareto), videotaping jobs, searching for solutions, between- operations analysis, and within-operation analysis.
3.1. What to Study (Pareto)
Engineering time is a valuable resource; don’t waste time on unimportant problems. To check quickly whether a project is worth considering, calculate (1) savings / year if material cost is cut 10% and (2) savings / year if labor cost is cut 10%.
The concept of the ‘‘insignificant many and the mighty few’’ (Pareto distribution) is shown in Figure 7. Cause (x-axis) and effect ( y-axis) are not related linearly. The key concept is that the bulk of the problem (opportunity) is concentrated in a few items. Pareto diagrams are a special form of a histogram of frequency counts; the key is that the categories are put into order with the largest first and smallest last; then a cumulative curve is plotted. Therefore, using the Pareto concept, if your design concerns crime, it should concentrate on the few individuals who cause most of the crimes; if it is to improve quality, it should concentrate on the few components that cause most of the problems. See Table 13. Fight the giants!
3.2. Videotaping Jobs
Videotaping is useful for task analysis and for training. Some tips are:
• Have spare batteries and a battery charger. A charger may take eight hours to recharge a battery.
• Use a camera feature that continuously displays the date on the screen; this establishes without question when the scene was shot. You may wish also to photo a card with the operator’s name.
• Plan the location of camera and subject ahead of time. Use a tripod. Multiple views are best. Use some combination of a front view, a side view, a back view, ‘‘stepladder’’ views (a partial- plan view), overall views, and closeup views. Begin a scene with a full view (far shot, wide- angle view) and then zoom as desired.
• If possible, videotape multiple operators doing the same task. This permits comparisons of methods. Small differences can be detected on tape because the tape can be frozen and / or repeated. For example, how are items oriented? Is the sequence of steps the same? Does one operator deviate joints more or less than other operators?
• If the view is perpendicular to the operator front or side, the projected view can be frozen and angles determined on the screen using a protractor. These angles can then be used as input to computer models.
• Take lots of cycles for your stock tape. Each scene should have several cycles. You can always edit, but it is expensive to go back and shoot more tape.
• For analysis of time, there are three alternatives:
1. Put a digital clock in the scene.
2. Use a camera–VCR system with a timecode feature, which will allow you to quickly locate any time on the tape.
3. Count the number of frames (VHS has 30 frames / sec [0.033 sec / frame]).
• During taping, use audio only as a notepad. For management presentations and training, dub in a voice reading a script.
• The VCR should have both a freeze-frame and single-frame advance.
• For task analysis, have the operator as well as the engineer view the tape. The operator can point out to the engineer what is being done and why—perhaps with audio dubbing. The tape also can show the operator some problems and how other operators do the task.
• For a training or management presentation video, you will need to cut and paste your stock tape. For the script, divide a column of paper into two columns labeled audio and visual. In the audio column, enter the words to be read. In the visual column, enter the tape counter reading (start and stop) of the stock videotape. For your final tape, you also will use text shots created in the studio (title page, points you want to emphasize, conclusions, etc.), studio shots of you, and shots of still photos. Then create the final product by blending all the pieces. Perhaps you can even add music!
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