When choosing sensors for your IoT platform, IoT sensors are broadly categorized into two types.
It is concerned with how the output of a sensor changes in response to an input change following a steady-state condition.
Accuracy: Accuracy is a sensor's ability to provide a true measurement of whatever it is monitoring. There is some uncertainty in the measurement, which is usually expressed as a percentage of the full scale. Compared to a higher prior system, express how accurate the output is.
Absolute error = Measured value —True value
Relative error = Measured value/True value
Range: The sensor's range refers to the maximum and minimum values of the applied parameter that can be measured. Beyond these values, there is no sense or no kind of response.
Repeatability: Repeatability is the ability of a sensor to provide a constant output when there is constant input when acquiring a new sample.
Environmental Impact: Changes in the environment can impact the performance and accuracy of a sensor. For example, some sensors are particularly sensitive to temperature and humidity.
Precision: It is a measuring instrument's ability to provide the same reading when measuring the same quantity under the same prescribed conditions repeatedly. It denotes agreement rather than proximity to the true value between successive readings. It is related to the variance of a set of measurements. Precision is a necessary but not sufficient condition.
Sensitivity: Sensitivity is defined as the ratio of incremental change in system response to incremental change in input parameters. The slope of a sensor's output characteristics curve can be used to calculate it. The smallest difference in quantity will cause the instrument's reading to change.
Linearity: Linearity is a measure of how well the sensor’s response curve approaches a straight line
Drift: The difference in sensor measurement from a specific reading when held at that value for an extended period of time.
Repeatability: The deviation between measurements in a sequence under the same conditions. The measurements have to be made under a short enough time duration so as not to allow significant long-term drift.
2: Dynamic Characteristics
Zero-order System: The output immediately responds to the input signal. It does not contain any energy-storing elements. Potentiometers, for example, can measure linear and rotary displacements.
First-order System: When the output gradually approaches its final value, it contains energy storage and dissipation element.
Second-Order System: Complex output response in a second-order system. The sensor's output response oscillates before reaching a steady state.