1. Principles of response selection
2. Discrete control
3. Position control
4. Verbal and symbolic input
5. Voice input
6. Continuous control
7. Remote control

DECISION COMPLEXITY Speed response is dependent on the number of possible actions. Design complexity advantage: Hick-Hyman law

EXPECTATIONS Repsons expectancy. We carry out actions faster and more accuratley if they are expected

COMPATIBILITY Stimulus-respons compatibility. Movement and location. Att ska ngt öka så är kontrollen utformad så att jag ökar/höjer den

SPEED-ACCURACY TRADEOFF Positive correlation between repsonsetime and error rate. Faster → more errors. Error critical → longer responstime

FEEDBACK Let us know that something has happened. Sound is a good feedback indicator. So is light and color change. Best when it´s instant. Över 100ms för mkt

(on/off, yes/no)

Physical ”toggle” ngt som förändras mellan 2 (ell fler) positioner. Redundancy gain

Size matter small keys/buttons are problematic

Confusion/labeling

The need to move something from position X to position Y

Movement time time to reach control device/or move cursor to target

• Fitt´s Law: Indexing of difficulty. Om jag ökar avstånd eller minskar storleken blir uppgiften svårare.

Device Characters

• Direct position control: Touch screen, light pen
• Indirect position control: Mouse, Touch pad
• Indirect velocity control: joystick, piltangenterna

  Isotonic: free movement
  Isometric: ngt får fart o riktning i ex. spel 
  Isomentric springload: finner en neutral position

• Voice control

Any kind of lag in the system. VIKTIGT: Feedback mkt viktigt. Lag, mkt dumt. GAIN: change cursor/change position. Människor är väldigt förändringsbenägna

Task Performance

• Mouse: en av de mest flexibla o justerbara. Men behöver viss plats.
• Cursor Keys: poor for long distances

Workspace ⇒ Greater gain, greater displaysize.

• Vertical displyas, greater cost of movement.
• Physical environment

Numerical data entry

• Voice good but limited
• Linear array are poor (typ nummerlinjen längst upp på datorn)
• Numerical keypads: 123 bäst. 789 nästan lika bra

Linguistic data entry

• Qwerty
• Chord board

Benefits

• Information rich and natural
• Dual tasking

Costs

• Confusion and limited vocabulary
• Acoustic quality
• Compatibility issues

”the Tracking Loop”

2 felkällor: 
- command input
- disturbance input: vind, vibrationer -> brus alltså

THE INPUT Bandwith: the frequency in which corrections need to be made

CONTROL ORDER

1. Position control (0-order): Best choice when accuracy is important
2. Velocity control (first-order): Joystick, steeringwheel
3. Acceleration control (second-order) Raketers styrning. Big, sluggish, unstable. Byggs aldrig in i systemen. Förebygg med predictive mechanisms

TIME DELAYS AND TRANSPORTATION LAGS Rendering ex. Resurskrävande och inte helt direkt

• GAIN bygg in för att göra system smidigare
• STABILITY 3 orsaker till instabilitet
  1. Lag
  2. Gain to high
  3. Impatience
• OPEN LOOP

Not responding to error only goal. Know where the target is. How the system reacts to control. Highly skilled.

telerobotics

Working in hazardous environments Or with hazardous material

Need flexibility

• Visual info (?) hard with deepth perception
• Time delays, time feedback
• Ofta går det att bygga bort delays med hårdvara och bandbredd

Proprioceptive feedback – fysisk feedback?

Modelling Mars-sonderna tex finns både som fysisk modell och som datormodell för att testa olika saker innan själva Mars-sonden utför den faktiska uppgiften.