Closed loop

Closed-loop may refer to:

• A feedback loop, often found in:
  • Closed-loop transfer function, where a closed-loop controller may be used
  • Electronic feedback loops in electronic circuits
  • PID controller, a commonly used closed-loop controller
• Closed ecological system not relying on matter exchange outside of the system, as opposed to open loop
• Ecological sanitation systems or ecosan, intended to close the nutrient and water cycle
• Pulling water from one area of a reef aquarium and pumping it immediately elsewhere in the tank to create higher flow and minimize dead spots
• Closed-loop communication, a communication technique used to avoid misunderstandings
• Circular economy, one in which materials are consistently reused rather than discharged as waste
• Closed time loop, or predestination paradox, a paradox of time travel that is often used as a convention in science fiction
• Closed curve, a mathematical curve described as a set of continuous parametric equations over a closed interval of real numbers for which the start point equals the end point
• Knot loop

See also

• Short circuit