input devices

Question 1

input devices

Answer 1

sense physical properties of the interaction with a suer and translate them into user interface events and parameters

Question 2

what are the 4 types of input

Answer 2

text
spacial e.g. pointing
directly mapped control e.g. function keys
media capture; audio visual scannable codes

Question 3

what are the 5 properties that can be sensed with input devices

Answer 3

linear/rotary; e.g. slider vs knob
position/force
absolute/relative e.g. up/down vs scrolling
1dimensional or more
discrete/continuous

Question 4

what are the states in the 3 state model of pointing devices

Answer 4

0; out of range
1; tracking
2; dragging

Question 5

what are the 3 types of controllers

Answer 5

isotonic
isomorphic
elastic

Question 6

isotonic controller

Answer 6

free moving and senses displacement
mouse

Question 7

isomorphic controller

Answer 7

non moving and senses force
ibm trackpad

Question 8

elastic controller

Answer 8

increasing resistance and can sense displacement and/or force
thumbsticks on controller

Question 9

direct control (cd relationship)

Answer 9

motor space = display space
the input is tracked directly onto the ui
touchscreen

Question 10

indirect control (cd relationship)

Answer 10

motor space != display space
device is represented by a cursor

Question 11

what are the 2 orders of control

Answer 11

position 0 order
rate 1st order

Question 12

position order (0 order control)

Answer 12

input mapped to position by how much the controller moves
e.g. isotonic controller

Question 13

rate control (first order control)

Answer 13

input mapped to speed of cursor
better at sensing force
isomorphic controllers

Question 14

cd gain formula

Answer 14

v display/ v control

Question 15

what is the cd gain for direct control

Answer 15

no gain as 1:1

Question 16

cd gain > 1

Answer 16

cursor faster than input

Question 17

cd gain < 1

Answer 17

cursor moves slower than input

Question 18

transfer function

Answer 18

mapping of the input from motorspace to display space
and can implement dynamic cd gain

Question 19

trade off of touchscreen

Answer 19

fast but inaccurate

Question 20

trade off of mouse

Answer 20

best with speed and accuracy

Question 21

trade off of trackpad

Answer 21

inefficient but close the the keyboard

Question 22

trade off of pointing stick

Answer 22

inefficient for very small movements but can keep hands on the home row

Question 23

input modes

Answer 23

the same input device can have a different effect

Question 24

mode errors

Answer 24

when the user is not aware of the current mode