A sensor can be considered an artificial sense organ in technology. With a sensor, a system perceives its environment or collects information that can be used to control actions. Most sensors are either electronic or mechanical, providing a fixed output based on a certain input.
Naturally, different sensors exist for various applications. Here's a brief list of quantities you can measure with sensors:
When choosing a sensor, it's important to know the voltage at which the sensor operates. Too high voltage will destroy the sensor, and too low voltage will make it work improperly or not at all. Mechanical sensors are less affected by this.
All sensors have one or multiple outputs. An output sends a measurement value from a sensor. The nature of this signal depends on the type of the sensor's output.
It's important to know that a sensor has a certain measuring range. This range is clearly indicated for each sensor. If there's a range from 5mm – 250mm, the sensor can only measure within these distances. Any distance outside this range will either produce no output or an undefined one. These distances vary from sensor to sensor.
By resolution, we mean "the smallest possible change a sensor can detect." For a positioning laser, this would be a shift or deviation in position. Often, higher resolution is associated with a more expensive sensor and/or slower reading time, so don't immediately opt for the highest available resolution.
Generally, sensors are very reliable if you stay within their specifications. It's crucial to choose the right sensor for the application and consider its properties. A low-resolution sensor, for instance, will not be reliable for positioning objects on a PCB but will be reliable enough for less precise work, like avoiding obstacles with a robot.
Maintenance varies by sensor type. Mechanical sensors often require more maintenance than electronic sensors. Sometimes it's necessary to clean the sensor or replace components like lenses or filters. For sensors used in an industrial setting, regular inspection and calibration are recommended to ensure reliable operation.
Calibration is crucial to ensure the accuracy of a sensor. The process depends on the type of sensor but generally involves comparing the sensor's output with a known standard value. Based on this comparison, adjustments are made as needed. Many sensors have built-in calibration procedures, but some require external equipment.