Human Control of Systems Chap 10

Human Control of Systems ► Compatibility   ► Tracking   ► Supervisory Control  

Compatibility  Degree to which relationships are consistent with human expectations  Compatibility   learning , error , RT , Compatibility   satisfaction   相容性有各種不同程度；有可能互相矛盾 ► Spatial Compatibility ► Movement Compatibility

Compatibility − Spatial ► Physical Similarity of Displays and Controls  Signal panels & Response panels Fig 10-1 Fig 10-1 Fig 10-1  Function keys: monitor – keyboard Fig 10-2 Fig 10-2 Fig 10-2 ► Physical Arrangement of Displays and Controls  Control-burner arrangements of stove Fig 10-3 Tab 10-1 Fig 10-3Tab 10-1 Fig 10-3Tab 10-1  Performance≠ Chosen ( II ＞ III ) ( III ＞ II ) ( II ＞ III ) ( III ＞ II )  Sensor lines  error=0, but RT > offset (I) Fig 10-4 Fig 10-4 Fig 10-4

Compatibility ► Movement Compatibility  Rotary Controls and Rotary Displays in the Same Plane  Rotary Controls and Linear Displays in the Same Plane  Movement of Displays and Controls in Different Planes  Movement Relationships of Rotary Vehicular Controls  Movement Relationships of Power Switches  Orientation of the Operator and Movement Relationships  Discussion

Compatibility − Movement ► Rotary Controls and Rotary Displays in the Same Plane  Fixed Scale Clockwise turn of Control  Clockwise turn of Display (pointer) (increase the value)  Fixed Pointer Fig 10-5 Fig 10-5 Fig 10-5 − 1. Scale rotate = Movement of Control − 2. Scale: L  R  increase − 3. Clockwise (control)  increase 重要性： 1>2>3 重要性： 1>2>3

Compatibility − Movement ► Rotary Controls and Linear Displays in the Same Plane Fig 10-6 Fig 10-6 Fig 10-6  Warrick’s Principle  Scale-side Principle  Clockwise – for – Increase Principle

Compatibility − Movement ► Movement of Displays and Controls in Different Planes  Control: rotary − Clockwise – for – Increase Principle − 螺絲類比： Clockwise  away from Counterclockwise  toward Counterclockwise  toward  Stick-type Control Fig 10-7 Fig 10-7 Fig 10-7 − Best: Up-Up, Down-Down − Worst: Up-Down  Recommended Fig 10-8 Fig 10-8 Fig 10-8  Safer: fore-up, aft-down

Compatibility − Movement ► Movement Relationships of Rotary Vehicular Controls Fig 10-9 Fig 10-9 Fig 10-9  Most vehicles  Shuttle cars for underground coal mines ► Movement Relationships of Power Switches  On: Up (chosen: 97%) > Right (71%) > Away (52%)

Compatibility − Movement ► Orientation of the Operator and Movement Relationships Fig Fig Fig  1. Control-Display Compatibility  2. Visual-Motor Compatibility  3. Visual-Trunk Compatibility 重要性： 2 (V-M) > 3 (V-T) > 1(C-D) 重要性： 2 (V-M) > 3 (V-T) > 1(C-D)

Compatibility − Movement ► Discussion  Not universal  Standardized; logical & explainable relationship  Empirical test

Tracking ► Inputs and Outputs in Tracking ► Pursuit and Compensatory Displays in Tracking ► Control Order of Systems ► Control Responses with Various Control Orders ► Human Limitations in Tracking Tasks ► Factors That Influence Tracking Performance ► Procedures for Facilitating Tracking Performance

Tracking  An input specifies the desired output of the system ► Inputs and Outputs in Tracking  Inputs − Can be constant or variable − Received directly from environment − Input signal = Target − Movement of target = Course − Elementary inputs: sine, step, ramp Fig Fig Fig  Outputs

Tracking ► Inputs and Outputs in Tracking  Inputs  Outputs − Display: follower, cursor − Outward behavior of the system (e.g. car) − Controlled element ( 上述兩項的總稱 )

Tracking ► Pursuit and Compensatory Displays in Tracking  Target = Controlled element : “On target” Fig Fig Fig  Pursuit: 呈現 Target & Controlled element  Compensatory: 只呈現 difference  Pursuit 之優點 − 可分離 Movement of target, controlled element − 可看到 Target course  Compensatory 之優點： 節省空間

Tracking ► Control Order of Systems Hierarchy of control relationships between the movement of the control & the output it controls  Position (Zero-Order) Control  Rate (First-Order) Control  Acceleration (Second-Order) Control  Higher-Order Control − Sequence of chain-reaction effect

Tracking ► Control Responses with Various Control Orders Fig Fig Fig  Zero-order, 1st-order: 佳  2nd-order:   原因 − Ｈ igher-order 動作多 − (e.g.) step input

Tracking ► Human Limitations in Tracking Tasks  Processing Time − Zero-, 1st-order: ms − 2nd-order: ms  Bandwidth ( 變化頻率） − 0.5 ~ 1 Hz (Central processing limit)  Anticipation − Higher-order: 差

Tracking ► Factors That Influence Tracking Performance  Preview of Track Ahead − Immediately procede ( 0.5 s) > Lagged preview − Enable operator to compensate for time lags  Type of Display: Pursuit vs. Compensatory − Pursuit > Compensatory Tab10-2 Fig Tab10-2Fig Tab10-2Fig − 原因： separate effect, greater movement compatibility − Digital display: no difference

Tracking ► Factors That Influence Tracking Performance  Time Lags in Tracking − Degrade operator performance − Working memory & Anticipate future event  − Types: Response lag, Control-system lag Fig 10-14, Display-system lag Fig Fig  Specificity of Displayed Error in Tracking − Specificity   Performance  Fig Fig Fig  Paced vs. Self-Paced Tracking − Self-Paced > Paced

Tracking ► Procedures for Facilitating Tracking Performance  Aiding (effect: limited)  Predictor Displays *** − Present state + Predicted future state − (e.g.) submarine, airplane landing Fig Fig Fig  Quickening − 只呈現 future consequences − 缺點：不知當時，錯誤 on target 印象

Supervisory Control  Degree of automation Tab 10-3 Tab 10-3 Tab 10-3 ► Supervisory Roles ► Future Implications of Supervisory Control

Supervisory Control ► Supervisory Roles  Sheridan (1987): 5 major categories of behaviors − Planning − Teaching − Monitoring − Intervening − Learning (troubleshooting)  Behavior Taxonomy of Rasmussen (1983) − Skill-based (Information as Signal) − Rule-based (Sign) − Knowledge-based (Symbol: conceptual model, mental model)

Supervisory Control ► Future Implications of Supervisory Control  Less capable of intervening in the control of the system during an emergency  Lack the necessary skills required to take control  Possibility of human error during an emergency: increase  Long-term Social Implications (Sheridan, 1980, 1987)

Supervisory Control ► Future Implications of Supervisory Control  Long-term Social Implications (Sheridan, 1980, 1987) — Unemployment — Desocialization — Remoteness from the product — Deskilling — Intimidation ( 脅迫 ): 犯錯  代價  — Discomfort in the assumption of power — Technological illiteracy — Mystification — Sense of not being productive — Eventual abandonment of responsibility