Sensors and Actuators Flashcards

Flashcards based on lecture notes about Sensors and Actuators, covering definitions, classifications, and parameters.

Sensor

A sensing device used to obtain environmental input values.

Actuator

Output devices used to control the environment in a system.

Range (of a sensor)

The lower and upper limits within which input may vary.

Span (of a sensor)

The difference between the upper and lower limits of the range of a sensor.

Error (of a sensor)

A measure of deviation in measurement value from the actual value of the quantity being measured.

Sensitivity (of a sensor)

The change in output quantity of a sensor per unit change in the input value to the sensor.

Accuracy (of a sensor)

The closeness between measurement and the actual value.

Resolution (of a sensor)

The smallest detectable incremental change of input parameter that can be reflected in the output signal of the sensor.

Stability (of a sensor)

Refers to the ability of the device to produce constant output.

Dead band/time (of a sensor)

The range of input values for when a transducer does not produce any output.

Repeatability (of a sensor)

It refers to the ability of the sensor to produce the same output in response to the same input being applied repetitively.

Response Time (of a sensor)

It is defined as the speed of change in output corresponding to a stepwise change in input.

Hysteresis (of a sensor)

It refers to a type of error displayed by the sensor devices corresponding to the situation about whether the input is on increasing trend or on decreasing trend.

Nonlinearity (of a sensor)

The maximum deviation of the actual measured curve from the ideal one.

Passive Sensor

Power required to produce the output is provided by the physical phenomena being sensed.

Active Sensor

Requires an external power source to operate.

Analog Sensors

Produce continuous signals proportional to the sensed parameters.

Digital Sensors

Output can often be fed directly to a processor.

Linear/Rotational Sensors

Measure displacement, position, or angular rotation of an object.

Acceleration Sensors

Detect changes in velocity or motion, often in multiple axes (X, Y, Z).

Force, Torque, and Pressure Sensors

Measure physical stress, such as force applied, twisting torque, or fluid/gas pressure.

Flow Sensors

Measure the rate of fluid or gas flow through a pipe or channel.

Temperature Sensors

Detect thermal conditions or changes in temperature.

Proximity Sensors

Detect the presence or absence of an object without physical contact.

Light Sensors

Respond to light intensity or specific wavelengths of light.

Electromechanical Actuators

Convert electrical energy into mechanical motion through a mechanical system, usually rotational or linear.

Electromagnetic Actuators

Operates based on the magnetic field generated by electric current, causing movement or force.

Hydraulic Actuators

Uses pressurized fluid (usually oil) to produce linear or rotary motion.

Pneumatic Actuators

Uses compressed air to generate motion