As speed is the rate of motion, or equivalently the rate of change in position, many times expressed as distance d travelled per unit of time t, you need to measure distance and time to determine the speed. Since velocity is defined as a vector quantity, both speed and direction are required to define it and to measure the speed you have to determine the time and the displacement. The velocity of an object is its speed in a particular direction. Velocity can also be defined as rate of change of displacement or just as the rate of displacement. The scalar absolute value (magnitude) of velocity is speed.Our sensors are based on two different measurement principles. So it is important to know how to calculate displacement and velocity of an object. OPTIPACT is measuring the displacement directly. To calculate the velocity you just have to measure the time for the displacement or keep the time in between constant (e.g. with a constant cycle time). Mathematical you have to differentiate distance and time to get the velocity.COVIDIS is measuring differently. By measuring the time respectively a frequency of changes the displacement (in this case the grid spacing of the spatial filter) between the measurements is kept constant. As a result you get the velocity. To calculate the displacement you have to integrate the velocity over the measured time.
