This muscle sensor from Advancer Technologies measures a muscle’s activity by monitoring the electric potential generated by muscle cells. This is referred to as electromyography (EMG). The sensor amplifies and processes the complex electrical activity of a muscle and converts it into a simple analog signal that can easily be read by any microcontroller with an analog-to-digital converter (ADC), such as an A-Star or Arduino– or even a Maestro servo controller like we show in this blog post. As the target muscle group flexes, the sensor’s output voltage increases. The exact relationship between the output voltage and the muscle activity can be fine-tuned using an on-board gain potentiometer.
The MyoWare Muscle Sensor is an updated version of Advancer Technologies’ older Muscle Sensor v3 with a number of improvements, notably single-supply operation (no need for a negative voltage supply) and built-in snap connectors for electrodes. Other new features include a raw EMG output, reverse power protection, a power switch, and LED indicators.
In order to attach to skin, the sensor requires three electrodes (not included) that snap into the sensor’s snap-style connectors, which make it easy to attach and detach electrodes. Two connectors are located directly on the PCB, and the third is located at the end of the attached reference electrode cable. The board’s pins have a 0.1″ pitch and work with 0.1″ male headers and 0.1″ female headers.