A Transducer is a device that converts variations into a measurable physical quantity i.e., pressure into Electrical signals or the other way round. Strain Gauge, Hydraulic, and Pneumatic are the commonly used Transducers. Strain Gauge is used in numerous industries like Automobile, Medical, and Weighing, etc. Load cells are also a type of force Transducer.
The process of converting forces into electrical signals is called Transduction. Transducers can be segregated into two broad categories based on the Energy conversion; Mechanical Transducers and Electrical Transducers. Mechanical Transducers convert physical quantities to mechanical quantities whereas, Electrical Transducers convert physical quantities to Electrical quantities, as the name suggests.
The different types of Transducers are:
Sensor: A type of transducer that reacts to a signal from a physical system. Usually, a signal is produced which gives out information from the system and this information is further used by a control system. These sensors can be subcategorized into active sensors and passive sensors. Active sensors require an external power source to function whereas, passive sensors do not require this. Active sensors can produce amplified signals whereas, Passive sensors are direct sensors that can change their physical properties.
Actuator: It is a device that is responsible for the movement and controlling of a system. It can be controlled manually or through signals from the controller system. It is operated by a source of energy and the energy is converted into motion. This source of energy can be anything from mechanical force to pneumatic pressure.
Bidirectional Transducer: This converts the physical energy to electrical signals and vice versa. A relevant example of a Bidirectional Transducer is an Antenna that converts radio waves into electrical signals that can further be used by the receiver.
On the conversion of the signal. there are two types of transducers, Analog and Digital. These are available with an option of input and output to choose from. It depends on the type of signal that is being controlled.