Magnetic Sensors
Magnetic sensors have been around since the mid 19th century, when they were used to measure magnetic fields. Today, they are used to measure a wide range of parameters including current, voltage, temperature, pressure, and position. Magnetic sensors are commonly used to detect objects in motion or for monitoring and controlling a system.
Magnetic sensors are usually based on two types of detection: magnetic-resonance and Hall effect. Magnetic resonance magnetic sensors use a coil of wire and a magnet to induce an alternating magnetic field in the surroundings. When a ferromagnetic object comes close to or moves through the magnetic field created by the coil, it can cause changes to the field. This change is then detected by the coil, allowing the device to detect the object.
Hall effect magnetic sensors, on the other hand, make use of the Hall effect principle to measure changes in the magnetic field strength. This effect is based on the movement of electrons in the presence of a magnetic field and occurs when a conducting material is placed between two parallel plates. As the magnetic field strength changes, it affects the way the electrons move. This, in turn, results in a voltage change that is proportional to the magnetic field changes, which can be measured and used to detect the presence of an object.
Common applications of magnetic sensors include position tracking and control of electric motors, as well as various automotive applications. Magnetic sensors are ideal for detecting the presence of metal objects, and can be used for wirelessly controlling robotic arms, anti-theft systems, and machine vision systems.
In the past, magnetic sensors were relatively expensive and difficult to implement but with the advancement in technology, the cost has gone down and the accuracy, sensitivity and range of the sensors have improved. This has opened up numerous new applications for magnetic sensors in areas such as medical diagnostics and automotive safety. For example, magnetic sensors can be used to measure the position of a patient’s bed, to detect and monitor oxygen levels, and to detect the presence of metallic objects in an engine.
In conclusion, magnetic sensors are widely used in a number of industries. Their versatility and improvemet in accuracy, sensitivity and range make them ideal for a wide range of applications.
