Single and Double Sheet Detection
Telling one sheet of paper from two, with sound instead of a mechanical gate.
A feeder that pulls two sheets at once jams the machine downstream, and the two sheets look identical to a camera pointed at the top one. Ultrasound looks through instead of at: the wave that crosses two sheets and the air gap between them arrives changed in amplitude compared with the wave that crosses one.
Distinguishing a single from a double sheet is a named application scenario for our material recognition transducers, alongside material recognition in sweeping robots. The measurement is non-contact, so nothing touches or marks the paper, and it is insensitive to print, gloss and colour.
Sensors for this application
Ultrasonic Material Recognition Sensor 1
A reflection-type ultrasonic transducer that reads back the change in frequency and amplitude of the returned wave, so metal, plastic and wood separate cleanly without any contact with the target.
View specifications →
Ultrasonic Material Recognition Sensor 2
The same reflection-type sensing element supplied on a twisted, colour-coded harness with a pitch connector already fitted, so it drops straight onto a board-level mating header.
View specifications →Is this your application?
Send the geometry and the two states you need to tell apart. We will say whether the echo difference is usable before you build a fixture.