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Open -Loop Control system is called as Manual control system.
Advantages:
1. Simplicity and stability: they are simpler in their layout and hence are economical and stable too due to their simplicity.
2. Construction: Since these are having a simple layout so are easier to construct.
Disadvantages:
1. Accuracy and Reliability: since these systems do not have a feedback mechanism, so they are very inaccurate in terms of result output and hence they are unreliable too.
Due to the absence of a feedback mechanism, they are unable to remove the disturbances occurring from external sources.
also can say it in another way:
Open loop means you pick the set point of a system and whatever comes out comes out. No system is perfectly "stiff", so the output will vary somewhat, sometimes quite a lot, depending on load.
Closed loop is when something is actively watching the output and adjusting the set point to whatever it takes to get the desired output.
Think of the gas pedal in your car. From gas pedal to car speed is a open loop system. You can push the pedal down to a fixed spot, and the car will go faster or slower depending on whether it's going up a hill or not and what else it has recently done. Now consider cruise control. That's puts feedback around the open loop gas pedal to car speed system to regulate the speed. It watches the speed and effectively steps harder on the gas when it notices the car slowing down, and lets up on the gas when it goes faster than desired.
The advantage of a closed loop system should now be obvious. You get to control the parameter you really want to control (the car speed in this example), and it automatically gives the system the right input (the gas pedal setting) to achieve the desired result. Of course this comes at the cost of extra stuff and complexity.
Closed loop control systems also need to be designed carefully so that they are stable. For example, if the cruise control always slammed the gas pedal to the max whenever the car was a little below the set speed, and completely let up when a little above, you'd have a very jerky ride and it would put a lot of stress on various parts of the car. Usually there are some tradeoffs the designer can make between the maximum error, the speed of response to changing conditions, and stability.
The group of elements/objects used to perform a specific task to attain the desired output is called system and conducted in a predefined way or sequence. This system is controlled to produce a specific output by controlling the other system and thus, we can say the system which controls other system is called control system.
There are various types of control system but all of them are created to control outputs. The system used for controlling the position, velocity, acceleration, temperature, pressure, voltage and current etc. are examples of control systems.
A control system in which the control action is totally independent of output of the system then it is called open loop control system, which is also called as Manual control system. example-Electric Hand Drier, Bread Toaster, Automatic Tea/Coffee Maker.
As open loop control syatem is operated manually, their design will be simple and for the same reason less expensive. Thye will be more stable and economical also compared to closed loop control system.
The disadvantages are low accuracy and reliability as human error and other disturbances can effect it. Feed back system is also not efficient
Light Switch – lamps glow whenever light switch is on irrespective of light is required or not. A-Advantages of Open Loop Control System:- 1-Simple in construction and design. 2-Economical. 3-Easy to maintain. 4-Generally stable. 5-Convenient to use as output is difficult to measure. B-Disadvantages of Open Loop Control System:- 1-They are inaccurate. 2-They are unreliable. 3-Any change in output cannot be corrected automatically. Volume on Stereo System – Volume is adjusted manually irrespective of output volume level.
Easy to assemble and very low cost in asembling
Simple in use But can't be checked response is According to desired value or not
Explain the bikes on system with all theory