Selasa, 05 Juni 2012

Sensor and Actuator



Sensor and Actuator

Controller or automation system will not escape the so-called 'censorship'. Because a control system in general has a procedure and a series of interrelated processes. Starting the change process that is captured and processed by the signal processing / data which is then passed on as though the output of the data in the form of control conditions. All of these processes will also be on the adoption of robotics in the world and even the series is exactly what the process becomes a routine process / core parts of the robot in which blood flow can be described as a robot.

What is a transducer?
The transducer is a device that converts energy from one form to another, which is an important element in the system controller. In general, the transducer divided into two working principles: firstly, the input transducer can be said that this transducer will convert non-electrical energy into electrical energy. Second, the transducer output is the opposite, converting electrical energy to a form of non-electric energy.

What about the sensor?
The sensor is a device for detecting / measuring something that is used to change a variety of mechanical, magnetic, thermal, and chemical rays into electrical voltages and currents. The sensor itself consists of a transducer with or without the amplifier / signal processor which is formed in a single sensing system. In environmental control systems and robotics, sensors provide commonality that resemble eyes, ears, nose, tongue, which will then be processed by the controller as the brain.

Various kinds of sensor?
Proximity Sensors (Proximity), the sensor or switch that can detect the target (metal type), with no physical contact. Sensors of this type usually consist of solid-state electronic devices are sealed to protect from the effects of vibration, fluid, chemical, and corrosive excessive. This sensor can be applied to sensing the condition of the objects that are considered too small / soft to drive a mechanical switch. Working principle is to consider changes in the amplitude of an environment of high frequency fields.

Sensor Magnet
also called reed relays, is a tool that will be affected the magnetic field and will give change in condition at the output. Like a two-state switch (on / off) which is driven by the presence of a magnetic field around it. This sensor is usually packed in vacuum packs and free from dust, moisture, fumes or vapors.

Sensor Light
consists of three categories. Fotovoltaic or solar cell is a light sensor that converts light energy directly into electrical energy, with the irradiation of light will cause the movement of electrons and generate a voltage. Similarly, the photoconductive (fotoresistif) which will give the change in resistance (resistance) in the cells, the intensity of light received tinggin, the smaller the value detainees. While the Photoelectric sensor which is the working principle is based on the reflection due to a change in position / distance of a light source (infrared or laser) or a target pemantulnya, which consists of a light source and receiver pair.

Hall-effect sensors
designed to sense the presence of a magnetic object to change its position. Changes in the magnetic field causing constant pulse frequency that can then be determined, this type of sensor is used as a measure of speed.

Ultrasonic Sensor
works on the principle of reflection of sound waves, wherein the sensor generates sound waves which are then caught again by the time difference as the basis will sensor. The time difference between the sound waves emitted by the re-arrest of the sound wave is directly proportional to the distance or height of reflecting objects. Type of object that can be sensed such as: object solid, liquid, granular or textiles.

Pressure Sensor
This sensor has a wire strain gauge transducers, which convert mechanical stress into electrical signals. will sensor basic introduction to the change in resistance (transducer) that changes due to changes in the length and broad cross-section.

Temperature sensors
there are four major types of commonly used temperature sensors: thermocouple (T / C), resistance temperature detector (RTD), thermistor and IC sensor. Thermocouple consists essentially of a pair of hot and cold transducer connected / fused together, the differences arising between the connection with the reference junction that serves as a comparison.

Resistance Temperature Detector (RTD)
Based on the electrical resistance of metals varies proportional to temperature. Proportionality of this variation is consistent with the level of precision / high stability in the detection of resistance. Platinum is the material that is often used because it has a temperature resistance, kelinearan, stability and reproducibility. Thermistor is a resistor that is sensitive to heat that usually has a negative temperature coefficient, because when the temperature increases, resistance decreases and vice versa. This species is very sensitive to changes in resistance o 5% per C so it can detect small changes in temperature. The sensor is a temperature sensor IC with an integrated circuit that uses sensory chip silicon for weakness. Configuration have output voltages and currents are very linear.

Speed ​​sensor / RPM
sensing process is the reverse process of a motor, wherein a shaft / object rotating at  generator will produce a voltage proportional to the speed of rotation object. Rotary speeds are often measured using a sensor sensing the magnetic pulse (induction) that arise when the magnetic field occurs.

Sensor encoder (Encoder)
Is used to convert rotation into linear motion or digital signal, wherein the sensor monitors the rotation of the rotary motion of a tool. These sensors typically consist of two layers of encoding types, namely: First, additional rotary encoder (which transmits a certain number of pulses for each round) that will generate a square wave on rotated objects. Second, the absolute encoder (the equipping of certain binary code for each angular position) have the same way with the exception of work, more meetings or more square wave pulse which is generated so as to form a coding in a particular order.