E2_6_10

Option EHuman Factors Design : 

Option EHuman Factors Design Human Factors Design E.2.6 - E.2.10

E.2.6 Outline the use of the concept of “methods of extremes” to limit sample sizes : 

E.2.6 Outline the use of the concept of “methods of extremes” to limit sample sizes Designing for extremes This accommodates all the population identified Takes into consideration the largest percentile population E.g. When determining head clearance in an automobile

Slide 3: 

Designing for extremes And the smallest percentile population E.g. When determining the distance between the seat and the pedals of an automobile

E.2.7 Define population stereotypes : 

E.2.7 Define population stereotypes Population stereotypes are the long-term habits and well-ingrained knowledge that we have about the world (Kantowitz & Sorkin, 1983)

Slide 5: 

Population stereotypes are features of designs represented by socially-accepted symbols which indicate the function of the design. For example, notice the tap shown below. The dial has a blue dot.  Typically, blue represents "cold" while red stands for "hot".  This allows the user to distinguish between the two features of the design. The tap does not distinguish between "hot" and "cold".  Instead, it relies on the users familiarity with the design.

Task - Quiz : 

Task - Quiz Here is a population stereotype quiz, just answer the following questions: In order to turn a machine on, the worker should push the toggle switch upwards or downwards? If an arrow indicator is right of center on a display, in what direction should the worker turn the dial/knob in order to bring the arrow to the center mark? Clockwise or Counter Clockwise? "Pressure High", working with a fire crew, the hoseman yells, "Pressure High". What should be done to the water pressure? Lower the pressure or raise the pressure? If you had to assign the letters A, B, C, D to the four quadrants of a circle, only one letter per quadrant, in what order would you label the quadrants?

E.2.8 Describe the relevance of the use of population stereotypes in the design of controls for products : 

E.2.8 Describe the relevance of the use of population stereotypes in the design of controls for products Why is it important that population stereotypes are considered in the design of products and in particular controls? Mechanical products Anticlockwise = OFF Clockwise = ON Water & Gas Anticlockwise = ON Clockwise = OFF

E.2.9 Discuss the problems of displacing population stereotypes in the design of controls for products : 

E.2.9 Discuss the problems of displacing population stereotypes in the design of controls for products Left hand drive Right hand drive Riding a bike in a different Country, on the “other” side of the road/track. What happens when you turn a corner? When your tired? Stressed?

E.2.10 Discuss how the use of converging technology in product design may lead to confusing control layout : 

E.2.10 Discuss how the use of converging technology in product design may lead to confusing control layout This picture shows the locks on our front door. To unlock the dead bolt lock (top), you turn the key to the right. To unlock the door knob lock (below), you turn the key to the left! That's pretty confusing! Michael J. Darnell http://www.baddesigns.com/deadblt.html for this example and the following slide

Slide 10: 

To turn the water on, you simply raise the lever up to the ON position. As long as the lever remains in the ON position, the water flows continuously. The photo in the center shows the lever in the up or ON position. I saw several people who had obviously never used a tap like this and who didn't know how to operate it. They pumped the lever rapidly up and down as if it were the handle of an "old fashioned" water pump. At the top of each stroke, the water would turn on and enough would come out to make them think they were operating the tap correctly. Needless to say, it required a lot of time and energy to fill their water container. Even though the tap looked like a hand-operated pump, it didn't work like one. The animation on the right shows the lever being pumped rapidly up and down. Zion National Park in southern Utah. There are water taps in various locations throughout the campground. On each water tap a lever, which looks like an "old fashioned" pump handle, is used to turn the water on and off. The photo at left shows a tap with the lever in the down or OFF position.

Task : 

Task Why may the operation of the controls of a combined electric cooker and gas cooker like the one shown above be confusing to the user? What possible safety hazards are there in this product?

Slide 12: 

Slide 8 - Quiz Results Most people will move toggle up to turn on Most people will move dial CCW General convention is that "Pressure high" means raise the pressure ABDC: 33% ABCD: 33% DACB: 33% Ref:http://www.rehabedge.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=25;t=001558;p=1

Links : 

Links http://www.rehabedge.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=25;t=001558;p=1 http://www.webword.com/moving/population.html http://www.baddesigns.com