NSF/ASEE WORKSHOP ON CREATIVE AND STRUCTURED DESIGN METHODS
Exercise 3: Evaluation - ELECTRIC DRILLS
An electric drill is to be selected for domestic use. Data for three candidate drills are given in the table below.
(a) Use this table to prepare a set of approximately ten assessment criteria and rank these requirements in order of importance by preparing an Objectives Tree.
(b) Make a quantitative evaluation of the three drills using an Evaluation Chart.
(c) Discuss the strengths and weaknesses of the evaluation procedure used in part (b). Make any suggestions you can for overcoming these weaknesses.
|DRILL A||DRILL B||DRILL C|
|Output power, W||240||315||365|
|Max speed, rpm||3100||2600||2600|
|Variable speed control||No||Yes||Yes|
|Feedback on speed control||No||Yes||Yes|
|Chuck capacity, mm||1-10||2.5-15||1.5-13|
|Flex length, m||1.3||2.5||1.4|
|Widest hole in wood, mm||19||25||30|
|Widest hole in steel. mm||7||10||13|
|Performance, drilling steel||Average||Very Good||Good|
|Ease of handling||Poor||Good||Average|
Note: All three drills meet all electrical safety standards.
Papers due to Paul Clayton on 10/9/99