Familiar with Resistor

Familiar with Resistor

SUMMARY OF THEORY

Basically all materials have resistive properties but some materials such as copper , silver , gold and metal materials generally have resistance is very small . These materials deliver the electrical current well , so called conductors . The opposite of materials conductive , ie materials such as rubber , glass , carbon has a resistance greater resist the flow of electrons so called insulators .
Resistors are the basic components of electronics are always used in every electronic circuit because it could serve as a regulator or to limit the amount of current flowing in a circuit . With resistors , electric current can be distributed according to need . in accordance with his name is resistive resistor and generally made ​​of carbon . Unit resistance of a resistor is called Ohmatau denoted by symbol Ω ( Omega ) .
In the electronic circuit , the resistor is denoted by the letter " R " . Judging from the material , there are several types of resistors in the market between Other : Carbon Resistor , Wirewound , and metalfilm . There are also resistors that can altered resistance value include: Potentiometer , Rheostat and Trimmer ( trimpot ) . In addition there is also a resistor that changes its resistance when exposed to light called LDR(Light Dependent Resistor) And resistors resistance value will increase in size when exposed to temperatures panasyang name PTC (Positive Thermal Coefficient) and resistor resistance value will small increase when exposed to hot temperatures whose name NTC (Negative Thermal Coefficient).
For the type of carbon and metalfilm resistors are commonly used color codes to guide the value of the resistance (resistance) of the resistor. This resistor has a tube-like shape with two legs on the left and right. In the body there is a circle to form a ring color code, the code is great to know without having to measure the resistance with an ohmmeter. The color code is the manufacturing standards issued by EIA (Electronic Industries Association) as shown in Table 1.1.

Table 1.1 value on the ring resistor color

The amount of resistance of a resistor is read from the position of the front ring ring towards tolerance . Usually this tolerance ring position on the resistor body most corner too wide or more prominent , while the position of the first ring slightly inward. Thus the user is instantly know how the tolerance of the resistor . If we had been able to determine where the first ring next is read the resistance value .
Number of circular rings in accordance with generally large resistor tolerance . Usually the resistor with a tolerance of 5 % , 10 % or 20 % have 3 rings ( not including the tolerance ring ) . But resistors with a tolerance of 1 % or 2 % ( small tolerance ) has 4 rings ( not including the tolerance ring ) . The first ring and so on successively showed large unit value , and the last ring is pengalinya factor .
For example, a resistor with a ring of yellow , violet , red and gold . Gold ring is a ring of tolerance . Thus the sequence is the resistor color ring , the first ring is yellow , violet and second ring to the three red rings . The fourth ring is a gold -colored ring tolerance . From table 1.1 tolerance is unknown if the gold-colored ring , this means the resistor has a tolerance of 5 % . Resistance value is calculated in accordance with the order of the color . The first is to determine the unit value of the resistor . Because this resistor resistor 5 % ( which usually has three rings in addition to the tolerance ring ) , then the value of the units is determined by the first ring and the second ring . Still from table 1.1 , note the yellow ring and ring value = 4 violet value = 7 . So the first and second ring or yellow and violet respectively , the value of the unit is 47 . The third ring is a multiplier factor , and if the color red ring means pengalinya factor is 100 . So with this in mind the resistor value is the value of the multiplier unit x or 47 x 100 = 4700 Ohm = 4.7 K Ohm ( on the electronic circuit board typically in 4K7 Ohm ) and the tolerance is + 5 % . Meaning of tolerance itself is a minimum limit and maximum resistance value that is owned by the resistor . So the actual value of the resistor 4.7 k Ohm + 5 % is :
4700 x 5 % = 235
Thus ,
Rmaksimum = 4700 + 235 = 4935 Ohm
Rminimum = 4700 - 235 = 4465 Ohm
If the above resistor is measured by using an ohmmeter and its value is in the range of maximum and minimum values ​​(4465 s / d 4935) was still meets the standard resistor. This tolerance value is given by the manufacturer of resistors to anticipate the characteristics of materials that are not the same between the resistor with another resistor so that the electronics designer can estimate the tolerance factor in its design. The smaller the tolerance value, the better the quality the resistor. So that the market value of the resistor that has a 1% tolerance (eg resistor metalfilm) is much more expensive than the resistor has a tolerance of 5% (carbon resistor)
Another specification to consider in choosing a resistor on the draft resistance is a major addition to its huge wattage or the maximum power that can be detained by the resistor. Because the resistor works in aliri electric current, the power dissipation will occur in the form of heat:

The larger the physical size of a resistor , can demonstrate the greater ability of the resistor power dissipation . Generally available in the market size of 1/8 , 1/4 , 1/2 , 1 , 2 , 5 , 10 and 20 watts . Resistor which has a maximum power dissipation of 5 , 10 and 20 watts generally elongated rectangular -shaped beam is white , but some are cylindrical and usually for large size resistor resistance value printed directly on his body is not shaped rings of color , for example 100Ω5W or 1KΩ10W . Seen from the function , the resistor can be divided into :
1 . Fixed Resistors ( Fixed Resistors )
Ie resistor whose value can not be changed , so it is always fixed ( constant ) . This resistor is usually made ​​from nikelin or carbon . Serve as a voltage divider , regulate or limit the current in a circuit as well as zoom in and out voltage .
2 . Variable resistor ( variable resistor )
Ie resistor whose value can change with the shift or rotate the toggle on the device , so that the value of the resistor can be set according to the needs . Serves as a volume control ( adjust the size of the stream ) , tone control on the sound system , the level of tone control ( bass / treble ) as well as serve as a voltage divider current and voltage .
3 . NTC and PTC resistors .
NTC ( Negative Temperature Coefficient ) , the resistor whose value will become smaller when exposed to hot temperatures . While the PTC ( Positive Temperature Coefficient ) , the resistor whose value will increase if the temperature being cold .
4 . resistor LDR
LDR ( Light Dependent Resistor ) is a type of resistor that changes its resistance due to the influence of light . When exposed to light dark detainees greater value , whereas when exposed to bright light into the smaller value .
2 . CIRCUIT RESISTOR
In practice the designer sometimes requires resistors with a certain value . However, the value of the resistor is not in the shop , even the factory itself does not produce it . Solution to get a resistor with a resistance value that is unique can be done by assembling a few resistors to obtain the required resistance value . There are two ways to weave resistors , namely :
1 . Serial ways
2 . Parallel way
The series resistor in series will result in greater total resistance value .
Below is an example of resistors arranged in series .

Series resistor in the circuit applies the formula:

While the series resistor in parallel will result in replacement for the smaller resistance value.
Below is an example of resistors arranged in parallel.

On a parallel resistor circuit applies the formula:

3. Standard resistor values
Not all resistance values ​​are available in the market. Table 1.2 is a sample table of standard resistor value in the market. Data on the resistor on the market can be obtained from the Data Sheet issued by the manufacturer of resistors.
Table 1.2 Value standard resistor

Below are some formulas (Ohm's Law) that is often used in the calculation of electronics:

Where: V = voltage with units of Volt I = current in Amperes unit
R = resistance with Ohm unit
P = power to the unit Watt
Unit conversion:
1 Ohm = 1 Ω
1 K Ohm = 1 K Ω
1 M Ohm = 1 M Ω
1 K Ω = 1.000 Ω
1 M Ω = 1.000 Ω K
1 M Ω Ω = 1,000,000
(M = Mega (106), K = Kilo (103))
thank ya bro have read

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SENSOR AND TRANSDUSER

SENSOR AND TRANSDUSER

INTRODUCTION
In the closed-loop control system, sometimes the shape of the output signal energy plant not the same as the shape of the input signal so that energy can not be compared, therefore, needed to change sensors or transducers form output signal energy into a form of energy similar to the reference input signal. This section will explain about sensors and transducers including the functions in the transducer arrangement and classification systems and sensors based on signal energy forms measurable.

Sensor And transducer
Transducer is a physical device that is used to transform a signal from one form of energy into another form of energy or of the magnitude a physical one physical quantity to another. In general, the output transducer is an electrical signal that can be current, voltage, resistance, capacitance or frequency. Basically the sensor is also a transducer. Distinguishing between sensor with trnduser is application and use.
Transducer is one component in the system settings in particular, the closed-loop arrangement. Location of transducer or sensor in the system settings can be seen in the block diagram of a closed loop system the following settings:

In the closed-loop control system, sensor or transducer transform energy output signal from the plant into a form of energy similar to the reference input signal (setpoin).
Transducer or sensor response to the input signal can be either a first-order system or second-order. In general, transducer or sensor is a first-order system, the relationship between input and output transducers in the domain of s can be expressed in the transfer function as follows:

Where C * (s) and C (s) respectively are the input and output transducers, K is the gain and time constant t is the transducer or sensor. If the transducer time constant faster than the time constant of the plant, in this case the transducer time constant can be ignored so that the transfer function of the transducer is the proportional gain

Example : tachogenerator ( velocity transducer )
In general, the transducer or temperature sensor has a time constant very slow . Performance of a transducer or sensor that is expressed in 2 specifications technical specifications and dynamic specifications . Technical specifications stating how well the correlation between input and output transducer or sensor . Technical specifications consist of :
1 . accuracy
Accuracy is used to determine the maximum error expected from a transducer or sensor ( in % error )
2 . sensitivity
Sensitivity indicates the ability of the transducer or sensor can provide output to small input changes .
3 . resolution
Resolution stating that menyebabkab perubahab smallest input changes output transducer or sensor
4 . hysteresis
Hysteresis shows different output values ​​of the variable value measurement input from low to high and from high to low .
5 . repeatability
Repeatability expressed how well transducers or sensors provide output the same for a given input repeatedly . Dynamic specification states how fast the output changes occur to changes in input . Dynamic specification consists of :
1.Rise time
2.Time constant
3.Dead time
4.Respon frequency
5.Parameter such second-order damping ratio , natural frequency , settling time , and maximum overshoot . Based on the form of energy or the magnitude of the input signal , the transducer or sensor in the system settings can generally be classified into :
1 . Mechanical transducer or sensor . Including displacement sensors , location or position , level sensors , and motion sensors ( speed ) .. Mechanical transducers are widely used in the system servomekanik
2 . Transducer or temperature sensor Transducer or temperature sensor is widely used in the process control system .
Examples of displacement sensors , location or position :
1 . linear potentiometer
Linear potentiometer convert linear motion into a variable resistance can be converted directly into a voltage signal and / or currents .

The magnitude of the linear potentiometer output is :

2. rotary potentiometer
Rotary potentiometer change the angular motion into a variable resistance can be converted directly into a voltage signal and / or currents.

The magnitude of the linear potentiometer output is:

The use of rotary potentiometer on the motor position control system of AC 2 phase can you look like the following block diagram:

3. capacitive sensors
Capacitive sensors are used to change the capacitance changes into current signal or voltage.

The basic operation of a capacitive sensor can be seen from the equation for a capacitor parallel plates as follows:

dielekrik where K is a constant, 0 is the permittivity e0 = 8.85 pF / m, A is the area cross plate, and d is the inter-plate distance.
4. inductive sensor
If a nucleus (core) permeable put in an inductor as shown on the image, then the associated inductance will rise. Each new position of the nuclei produced different inductance. In this condition, a combination of the inductor and movable The core can be used as a displacement sensor.

Examples of level sensor:
1. float
One of the most common techniques for measuring level, especially for liquids, is a buoy that can go up and down according to changes in liquid level. This buoy is connected by linkage (liaison) to the measurement system secondary displacement as a potentiometer

2. ultrasonic
The use of reflection (reflection) to measure the level of ultrasonic preferred because is a technique that "noninvasive" (no damage), ie with no put anything in the material.
There are 2 techniques to measure levels using ultrasonic reflection, namely:
1. External technique: for solid / liquid material
2. Internal technique: for liquid material

Speed ​​sensor example: 1. tachometer
Tachometer is a transducer that is used to change the velocity signal into a voltage signal. The use of a tachometer on a DC motor speed regulation system can be seen such as the following block diagram:

Temperature sensor example:
1. bimetallic
Bimetal sensor that converts a temperature value changes to energy mechanics. Bimetal sensor consists of two different metals with a coefficient of thermal expansion (expansion temperature) that is attached to a different one (bonded together). coefficient of expansion thermal unequal on the two pieces of metal that will cause the bimetal curved.

If the temperature is decreased below the temperature setpoin t0, bimetal pieces will curve to the metal which has a lower coefficient of thermal expansion (bottom). Conversely, if the temperature rises above the temperature of the bimetallic pieces setpoin t0 will curve to the metal that has a higher coefficient of thermal expansion (above).
2. Resistance Temperature Detector (RTD) Resistance temperature detector (RTD) is a transducer that converts the change temperature value to the value of resistance in a metal.

The relationship between temperature and resistance is expressed by the following equation:

If the temperature change is small, can be approximated by the following linear equation:

It appears that the greater the RTD temperature the greater its resistance so called as Positive Temperature Coefficient (PTC)
3. thermistor
Thermistor is a transducer that converts a temperature value changes resistance value in a semiconductor.

The relationship between temperature and resistance is expressed by the following equation:

It appears that the thermistor temperature the greater the smaller the value resistance so called Negative Temperature Coefficient (NTC)
4. thermocouple
Thermocouple is a transducer that converts a temperature value changes emf (electromotive force).

Here's a thermocouple types and range of materials along with the area of ​​work:

SUMMARY
1.Pada regulatory system, sensor or transducer signal energy remodel output of the plant to be similar to that of the reference input signal energy. Widely used in mechanical.
2.Sensor servomekanik system and temperature sensor widely used in the process control system.

INTRODUCTION TO CONTROL SYSTEM

INTRODUCTION TO CONTROL SYSTEM

1.1introduction
Engineering ( engineering ) is concerned with understanding and controlling materials and energy / power in nature for the benefit of man . Control systems engineer ( control systems engineer ) associated with things to understand and control the parts of the environment are often called as a system , to produce an economical product for humans . Understanding and control (understanding and controlling) are two aspects complementary , because effective control system requires an understanding and proper modeling of a system . Contemporary challenges of control engineer is how to model and control system of the modern , complex , and interconnected , such as traffic control systems , chemical processes , and robotic systems .
Some definitions :
Controlled - variable ( Controlled Variable ) : quantity or condition measured and controlled . Generally it is the output of the system .
- Manipulated variables ( Manipulated Variable ) : quantity or condition altered / manipulated by the controller to change the value of the variable controlled .
- Plant : equipment , a collection of machine parts functioning which together aim to perform an operation .
- Process : every operation is controlled , such as chemical processes , economics , biology , etc. .
- System : a combination of components that work together to achieve a certain goal .
- Disorders ( disturbances ) : signals that affect the value of the output of the system .
If the interference is generated from within the system , referred to as internal disturbances, while those coming from outside the system is referred to as external disturbances. disturbances, while those coming from outside the system is referred to as external disturbances.  
Control system (control system) is an interconnection of components forming a system configuration that aims to generate a response desired. The basis for the analysis of a system is linear system theory, which assuming causality (cause-effect) for the components of a system. So that a component or process to be controlled can be expressed by a block as shown in Figure.

Input-output relationship expressed causality of the process, which declare a process of input signal to produce an output signal. a open-loop control system using the controller or actuator to obtain desired response, such as in Figure 1.2. In the open-loop system, the propulsion equipment (actuating device) is used to control the process directly, without the use of feedback (feedback).

Examples of open-loop control system is operated with a microwave oven certain period of time. Closed-loop control system using an additional measurement of the actual output to be compared with the desired output response. measurement output is called the feedback signal. Figure 1.3 shows an example of simple closed-loop control system.

Perbedaan antara output yang diinginkan dengan output aktual disebut sebagai error, yang selanjutnya akan di adjust (disesuaikan) oleh peralatan pengendali. Output dari peralatan pengendali menyebabkan aktuator memodulasi proses untuk mengurangi error. Sistem yang diperlihatkan pada gambar adalah sistem kendali negative feedback, karena output dikurangkan dari input dan perbedaannya digunakan sebagai sinyal input ke peralatan pengendali. Contoh sistem kendali closed-loop adalah seorang pengendara mobil yang melihat lokasi/posisi di jalan dan membuat penyesuaian yang tepat/seharusnya.

Open-loop vs. closed-loop
The advantage of the closed-loop control system is that the presence of feedback make the system response relatively unaffected by external disturbances and variations of internal system parameters. Stability of the system, the open-loop control system was made easier because of the stability system is not a major problem. But stability is a major issue the closed - loop control system , where the error will resolve error causes oscillations that lead to instability .
For systems where the input is known in advance and there is no interference ,then you should use an open - loop control system . Closed - loop control system have an advantage if there is interference that can not be predicted and / or variety of system components which can not be predicted .
Number of components used in the closed - loop control system more than those used in open - loop control system . Thus , the control system closed - loop generally need a large cost and energy . To summarize , the open - loop control system has the following main advantages :
- Construction is simple and easy to maintain
- It is cheaper than the closed - loop control system - its
- There is no stability problems
- Suitable for use if the system output is difficult to measure or measuring output is not economically feasible. ( Example : the washing system , will quite expensive to provide quality laundry gauge , namely cleanliness of the clothes are washed ) . While the main disadvantages of the open - loop control system are :
- Disorders and calibration changes caused the error , and will output different from the desired
- To maintain the quality of the output , recalibration should be carried out from time to time .


1.2 HISTORY OF AUTOMATIC CONTROL
 The first feedback system to be invented in modern Europe was the temperature regulator of Cornelis Drebbel (1572-1633) from Holland .
 Dennis Papin (1647-1712) invented the first pressure regulator for steam boilers in 1681 . Papin 's pressure regulator was a form of safety regulator similar to a pressure - cooker valve .
The first automatic feedback controller used in an industrial process is generally agreed to be James Watt’s flyball governor, developed in 1769 for controlling the speed of a steam engine. The all-mechanical device is shown in Figure.

The first historical feedback system, claimed by Russia, is the water-level float regulator said to have been invented by I. Polzunov in 1765. The level regulator system is shown in Fig. 1.6. The float detects the water level and controls the valve that covers the water inlet in the boiler.
1868: J. C. Maxwell formulates a mathematical model for a governor control of a steam engine.
1913: Henry Ford’s mechanised assembly machine introduced for automobile production.
1927: H.W. Bode analyses feedback amplifiers.
1932: H. Nyquist develops a method for analysing the stability of systems.

1952: Numerical control (NC) developed at Massachusetts Institute of Technology for control of machine-tool axes.
1954: George Devol develops “programmed article transfer,” considered to be the first industrial robot design.
1960: First robot introduced, based on Devol’s designs.
1961: Robots used for tending die-casting machines.
1970: State-variable models and optimal control developed.
1980: Robust control system design widely studied.
1990: Export-oriented manufacturing companies emphasize automation.
1994: Feedback control widely used in automobiles. Reliable, robust systems demanded in manufacturing.
1997: First ever autonomous rover vehicle, known as Sojourner, explores the Martian surface.
1998-2003: Advances in micro- and nanotechnology. First intelligent micromachines are developed and functioning nanomachines are created.

1.3TIPE FEEDBACK CONTROL SYSTEM
Based on the method of analysis and design of control systems can be classified as the following :
 linear and nonlinear control system : The system in practice is nonlinear . system linear control is an ideal model that is used to simplify analysis and design .
 The system does not change with time ( time - invariant ) and time-varying ( time -varying ) : time - invariant system is a system in which the parameters of the system control does not change with time during the operation of the system . almost all elements of the system in practice which has changed / varied to of time .
 continuous and discrete control systems : continuous system is a system where their signals is a function of continuous time variable . whereas discrete signal is a system where sinnyal - signal digital signal merupkan .
 System single variable ( single variable ) and many variables ( multivariable ) : Single variable system has a single input , single output ( SISO : Single input single output ) . Many systems have a lot of input variables and output ( MIMO : Multi- input , multi- output ) , as in the picture.

EXAMPLE 1.4 CONTROL SYSTEM
1.4.1 car steering control system
Block diagram of the steering control system is shown in Figure (a).Position (car trips) compared to the desired position measurement actual to generate an error as in Figure (b). This measurement is obtained of visual and tactile feedback (body movement). There is also an additional feedback from the steering wheel by hand (sensor). A typical response to the direction of travel shown in the picture.

FIGURE - (a)Automobile steering control system (b) The driver uses the difference between the actual and the desired direction of travel to generate a controlled adjustment of the steering wheel (c) Typical direction-of-travel response

1.4.2 System level control tank
Closed-loop control system (manual) to control the liquid level in a tank is shown in Figure 1.9. As the input is the reference level of the liquid desired (reference is remembered by the operator). Control equipment is operator, and the sensor is a visual sensor. Operators compare the actual level to the desired level and opening or closing the valve (actuator), which will adjust the discharge rate, thereby maintaining the fluid at desired level.

1.4.3 Three-Axis Control System
Figure 1.10 shows a three-axis control system for wafer inspection semiconductors. This system uses special motors to drive each axis to the desired position on the xyz axes. The purpose of the system control here is to get a smooth and accurate movement on each axis.

1.4.4 Power Plant
Today, control of the power plant to produce the minimum exhaust emissions be important. Large power plant requires an automatic control system take into account the relationship between process variables and power production. Power plant This generally has 90 or more variables are manipulated to control coordinated. Figure 1.11 shows the block diagram of the system simplified.

1.4.5 Model control system of national income
Simple model of national income control system is shown in Figure. This model is useful to help analysts understand the impact of regulation government and government spending dynamical

1.5 FUTURE CONTROL SYSTEM
Ongoing objective of the control system is to provide a flexible to - late and higher autonomy . Two kinds of approaches to achieve goals is shown in Figure 1:13 . Nowadays , industrial robots can be said autonomous enough - once programmed , in general no longer needed intervention humans . But because of the limitations of sensors , robotic systems have the flexibility which is limited to adapting to a changing work environment ; increase sensing system is a motivation in research in the field of computer vision .
Meanwhile, the control system is highly adaptive , but depends on the supervision humans . The robotic system made ​​for adaptive task through development of sensor feedback . Field of research that concentrates on intelligence artificial ( AI = artificial intelligent ) , the integration of sensors , computer vision , and programming CAD / CAM will make the system more universal and economical .
Control system is moving towards autonomous operation as an increase of human control . Research on supervisory control , human-machine interface , computer database management aims to reduce the limitations of operator and increase operator efficiency. Many research activities are conducted in the field of robotics and control systems and aims to reduce costs implementation and extend the application. This includes also improved methods communication and programming languages​​.
The theory, practice, and application of automatic control is a large, exciting, disclipine engineering and extremely useful.

1.6 DESIGN EXAMPLE:
1.6.1 ROTATING DISK SPEED CONTROL
Many modern devices that use a rotating disc at a speed constant. For example, a CD player, hard disk, etc. require a rotation speed constant despite the variations in the motor and other components change. Our objective is to design a control system which ensures that the disc speed actual speed of disc rotation speed is in the range desired . We will review the system without and with feedback . To play a disc , we choose a DC motor as an actuator for the motor DC can produce speeds in accordance with the applied voltage . to input voltage to the motor , we can use an amplifier to produce the required voltage .
Open - loop control system is shown in Figure 1:14 ( a) . The system uses battery source to generate the required voltage . the voltage further amplified and applied to the motor . Block diagram of the control system of open - This loop depicting control equipment , actuators and processes are shown in Figure.
To obtain feedback system , we need a sensor . One of the sensors are can be used is a tachometer that produces an output proportional to velocity axis. So that the closed - loop control system can be made as to figure . Block diagram of the closed - loop system is shown in Figure . Voltage error resulting from the difference between the input voltage and the voltage tachometer .
We can expect that the closed - loop control system on the image will better than the open - loop control system in Figure 1.14 , because the feedback system will respond and act to minimize error .

FIGURE
(a)Open-loop control (without feedback) of the speed of a turntable
(b)Block diagram model

(a) Closed-loop control (with feedback) of the speed of a turntable
(b) Block diagram model

1.6.2 CONTROL INSULIN DELIVERY SYSTEM
Control system has been used in the biomedical field to produce a system automated drug delivery to patients implanted (implant) in the patient's body. Automatic systems can be used to regulate blood pressure, blood glucose levels, and heart rate. One example is a system for controlling the levels blood glucose will be discussed below.
Blood sugar and insulin concentration for healthy people is shown in Figure . The system must be able to produce insulin made ​​from a container that grafted / implanted in diabetic patients . So that the control objectives are :
Control objectives :
Designing a system to regulate blood sugar concentration of diabetic patients with insulin control . With reference to the drawings 1:16 , then the next step is to define variables were controlled . Controlled variables :
Blood sugar concentration .
Controller design specifications :
Provide blood glucose levels for diabetic patients whose glucose levels following healthy people . With a given destination , controlled variables , and specifications , we can designing the initial configuration of the control system . With the control system of open - loop , it is necessary to producing a signal which can be programmed at the beginning of ( preprogrammed ) and mini bike pump to adjust the insulin infusion as shown in Figure ( a) . While the closed - loop control system using sensor to measure glucose level and compare it with the level desirable , so that the motor will turn on the pump if necessary , such as shown in Figure ( b ) .

FIGURE The blood glucose and insulin levels for a healthy person.

FIGURE (a)Open loop control; (b) Closed-loop control



Referensi :
1.Richard C. Dorf, Robert H. Bishop, 2008, Modern Control System 11th edition, Pearson Prentice Hall.
2.Katsuhiko Ogata, 2002, Modern Control Engineering 4th edition, Prentice Hall.