In a past life, I used strain gauges in a number of applications – measuring weight with a load cell, cable tension with a load cell or stain-gauged clevis pin, torsion in propeller shafts and other apps. All of these applications required expensive instrumentation that was sometimes difficult to set up and use.
I came across this HX711 module that's a complete strain gauge signal conditioner and excitation source for five bucks. Add an ESP32 and you have a wireless strain gauge system for the cost of lunch. Kind of unbelievable.
Sparkfun has an HX711 breakout board for just a little more, but it uses headers for connections that are probably inadequate for use with strain gauges (measurements depend on small deltas in resistance). The Banggood module has a 4-pin Grove connector for the microcontroller interface and a 4-pin plugable terminal block for the strain gauge bridge. I've started including 4-pin Grove connectors in my designs, as they have become somewhat of a standard for a number of Chinese suppliers, including Seeed Studios and Elcrow's Crowtail system.
One detail – the interface of the HX711 is not I2C but more like SPI with a clock and serial data.
I came across this HX711 module that's a complete strain gauge signal conditioner and excitation source for five bucks. Add an ESP32 and you have a wireless strain gauge system for the cost of lunch. Kind of unbelievable.
Sparkfun has an HX711 breakout board for just a little more, but it uses headers for connections that are probably inadequate for use with strain gauges (measurements depend on small deltas in resistance). The Banggood module has a 4-pin Grove connector for the microcontroller interface and a 4-pin plugable terminal block for the strain gauge bridge. I've started including 4-pin Grove connectors in my designs, as they have become somewhat of a standard for a number of Chinese suppliers, including Seeed Studios and Elcrow's Crowtail system.
One detail – the interface of the HX711 is not I2C but more like SPI with a clock and serial data.
