Page 14 - Industrial Technology EXTRA 16th August 2021

measurement within one 360 degree revolution of example of insulin administration, a drug delivery
the shaft, also known as the duty cycle or period. system requires a precise amount of medication
Generally, the greater the number of points, which dispensed at a specified rate and the encoder is
are termed Lines per Revolution (LPR) or Pulses per used to confirm that the exacting dose is delivered.
Revolution (PPR), the greater the measuring This example also shows how the greater number of
accuracy. For example, Portescap’s M-Sense lines for increased encoder resolution can help
magnetic encoder has up to 1,024 lines per ensure precision to the most exacting rate of flow.
revolution in a compact design. A robotic gripper can be used for example in
Each output, A and B, switches between high manufacturing to handle relatively delicate
and low. The two bits of information thereby create components. It’s key to ensure that the right amount
four times the counts for each line or pulse and this pressure and speed is used to correctly handle the
is known as quadrature decoding. Thereby, component to avoid damaging it.
quadrature decoding can increase resolution by up Thanks to an encoder, the robotic gripper’s
to four times, for example turning the Portescap function is optimised by the motion control of its
MR2 encoder’s 512 lines into 2048 counts or motor’s speed and position, specific to each
angular steps. In addition to the two A and B output component it handles.
channels, a third channel, Z, is sometimes included Similarly, pick and place applications used in
which can be used to determine the reference the assembly of electronic equipment require high
position. speed motion control to quickly and repeatedly
detect the size and weight of PCB components,
Where encoders are used placing them with precision. Encoders enable this
Understanding how encoders provide feedback for high speed, high accuracy control to ensure
motor control, we can see how their use is crucial productivity and quality of manufacture.
across various applications. Taking our original www.portescap.com

August 2021 • INDUSTRIAL TECHNOLOGY EXTRA • p14