CS 5540 HCI Assignment 1 Affordance and Mapping

CS 5540 HCI Assignment 1 Affordance and Mapping Brett Mc. Rae 9/17/2021 CS 5540 1

Definitions (your words) • Affordance: an object has affordance if by looking at it you can tell what it does and how to operate it • Mapping: an object is said to demonstrate good mapping if the right ways to interact with it were used in the right way 9/17/2021 CS 5540 2

Good and Poor Examples Affordance Mapping Good Poor 9/17/2021 CS 5540 3

Ex 1: Good Affordance • This was an engineering project of my brother's. He has not demonstrated it to me before, but because of its good affordance I could figure everything out that I needed to know. Because it has wheels I knew it was a car. The mousetrap is obviously the source of power. The tower is to hold up the string. You wind the string around the axle. 9/17/2021 CS 5540 4

Ex 2: Poor Affordance • Chair handle -- Nobody can figure out how to make this chair go up and down. There is a lever but it only moves forward and backward and turns a little bit, but this doesn't change the seat height. One user of this chair found that if you get off the chair and hit the handle with a lot of force, the seat will go up (getting it to go back down is another question). I figured out after a few weeks how it works: the handle moves forward and backward (why? ) but only when it's exactly centered (achieved through trial and error - and don't turn it!) will it move up and then you can raise and lower the seat. 9/17/2021 CS 5540 5

Ex 3: Good Mapping • Stereo Panel -- The switches for on/off, bass on/off and am/fm/tape/aux are all "real" switches and are vertical. Up is on, down is off. The volume is changed via a knob with ridges, and it is the largest thing on the dial, since volume changing is a common action with this device. The tuning is adjusted with a left/right wheel and maps well to the tuning display which is right next to it. The equalizer adjustments are all vertical sliders and are in order of frequency from lowest to highest. The only thing that doesn't map well is the balance which is a vertical slider instead of a horizontal one. 9/17/2021 CS 5540 6

Ex 4: Poor Mapping • Front door deadbolt -- Having to use a key to unlock the door from the inside only makes sense if you're trying to lock someone in. Maybe it's 'more secure', but anyone with this kind of lock would have a copy of the key made and leave it in the door, thus making it equivalent to a deadbolt with a knob. But when someone is in a hurry and can't find their keys, they will take the key out of the door, lock it and leave, and probably forget to return the key. Then when a visitor comes, the person inside will have to yell through the door, "I can't open it!" 9/17/2021 CS 5540 7

9/17/2021 CS 5540 8

9/17/2021 CS 5540 9

End of Assignment 1 9/17/2021 CS 5540 10