Schlagwort: Arduino Tachometer

  • Build your own tachometer with an IR sensor and an Arduino

    Build your own tachometer with an IR sensor and an Arduino

    Reading Time: 2 minutes

    A tachometer is a device that display the speed of a rotating object. The most well-known example is the automotive tachometer, which shows a driver the RPM of the engine — information that is particularly useful when the car has a manual transmission. But there are many other uses for tachometers and this tutorial from Mirko Pavleski explains how to build a tachometer with an infrared sensor.

    To calculate the rotational speed of something like a wheel, you need to monitor at least one point on that wheel and time the interval between passes by a static reference point. A common way to achieve that is with a Hall effect sensor that detects the magnetic field from a permanent magnet attached to the wheel’s rim. But Hall effect sensors are unsuitable for some applications, such as when there are strong magnetic fields nearby. Pavleski’s write-up demonstrates how to instead use an infrared sensor to detect the passing of the wheel’s spokes.

    This infrared sensor module works by emitting infrared light from an LED and monitoring the reflection. When one of the wheel’s spokes passes in front of the sensor, the reflection becomes strong and easy to detect. An Arduino Nano board measures the time between those events and multiplies the result by the number of spokes to determine the total time for a complete revolution. Divide 60 by that number and you get the RPM. The Arduino continuously calculates that value and displays the number on a small OLED screen. Power comes from a 9V battery.

    One of the great things about this design is that it doesn’t require contact with the measured object and since it is portable, so one can measure the RPM of anything spinning that has spokes.

    [youtube https://www.youtube.com/watch?v=0pLw3B1Q8dk?feature=oembed&w=500&h=281]

    The post Build your own tachometer with an IR sensor and an Arduino appeared first on Arduino Blog.

    Website: LINK

  • Build a tachometer for your metal lathe with Arduino

    Build a tachometer for your metal lathe with Arduino

    Reading Time: < 1 minute

    Build a tachometer for your metal lathe with Arduino

    Arduino TeamJanuary 2nd, 2019

    If you manage to get a small lathe in your home shop, it will likely come with a dial to adjust the speed, but it may not have a tachometer to tell you if it’s actually spinning at your desired setting. Rather than accept this imprecision on his model, hacker Tony Scarpelli designed his own non-contact tachometer using an Arduino Nano.

    The build is ingeniously simple, and mounts an infrared proximity sensor near gearing in the back of the lathe’s headstock. White paper is placed on this rotating surface, allowing the sensor to tell between this marker and the otherwise dark surface as it spins. Sensor pulses are recorded by the Arduino, which outputs RPM values on a small 16×2 LCD display.

    Website: LINK