OpenClosed Loop Systems INPUT You run the mile
- Slides: 8
Open/Closed Loop Systems ● INPUT: ● You run the mile every afternoon ● You record time with stopwatch ● OUTPUT: ● Stopwatch times each mile ● PROBLEM: Your times do not improve K C A DB E E F k c a r t n o ) ile s p m i t a un ( n K u C s r ur r A e u B v o o D Y s yo r E : p E T F m i U time ● P e u N I o im y t ● oach s e l i ve i C m g r h u c o a Y Co PUT: T U O 1/8
2/8 Open Loop System: ● One-way connection between INPUT and OUTPUT INPUT OUTPUT ON / OFF INPUT Wa ter ON /W OU ate r. O FF TPU T
3/8 Open Loop System: ● One-way connection between INPUT and OUTPUT ●NO direct connection between OUTPUT and INPUT EXAMPLE: light + switch INPUT: ON/OFF OUTPUT: ON/OFF ●Open Loop System: A control system with no automatic FEEDBACK loop
INPUT: set light,
Closed Loop System: 5/8 ●A control system with an automatic feedback loop ● A direct connection between OUTPUT and INPUT 140 ○ + - water temperature control “Heat water to 140 degrees” “Under 140: Start heating. ” “At 140: Stop heating. ” feedback temperature sensor/control Water heater
6/8 Closed Loop System: ● A direct connection between OUTPUT and INPUT EXAMPLE: outdoor lights w/motion detector Thief : near home at night Electric eye INPUT (infrare d wave detects s) infrared. F EED BA CK Spotlights turn ON. OUTPUT ●Closed Loop System: A control system with an automatic FEEDBACK loop
7/8 Closed Loop System: ● A direct connection between OUTPUT and INPUT EXAMPLE: daylight sensor controls interior lighting Natural daylight thru windows Ceiling-mounted daylight sensor INPUT OUTPUT low/no natural light: ADJUST lighting high natural light: ADJUST lighting ●Closed Loop System: A control system with an automatic FEEDBACK loop
Open/Closed Loop Systems 8/8 Below: 20 everyday technology systems/sub-systems Which are Open-Loop Systems? – ‘O’ Which are Closed-Loop Systems? – ‘C’ [1] Electric fan [2] Foot-operated gas pedal [3] Cell phone [4] Thermostat [5] Door bell [6] Food processor [7] Car cruise control [8] Lawn sprinkler system [9] Car automatic headlights [10] x. Box /Playstation [11] ‘Active’ noise-canceling headphones [12] Volume control on headphones [13] Window shade [14] Central Air Conditioning [15] Electric toothbrush [16] Car anti-lock braking system [17] Hair dryer [18] Traffic lights [19] Foot-operated brake pedal [20] Programmable croc pot w/temp probe