Advancer Technologies

It's just a standard Arduino Uno.

Many customers have used our sensors for various face muscle applications like a Bruxism (teeth grinding) detection system and this one from Adafruit that uses your eyebrow muscles to send tweets.https://learn.adafruit.com/heybrows

Yes

I'm not familiar with nitinol, sorry!

You'd probably be fine with 5% but I wouldn't go over that.

What report?

https://www.sparkfun.com/products/11570

You need to program the Arduino. I would recommend using the ReadAnalogVoltage example when just starting out.

The high pass filter with the cut off frequency of 106 Hz is not a mistake. EMG signals power spectrum is usually 10Hz - 1000Hz. When I made this circuit a decade ago I chose the high pass cut off to be above 60Hz to avoid electrical hum noise from the power grid 100 Hz will getsome of the harmonic frequencies too). We don't do this in our sensors because the CMMR of the instrumentation opamp we use sufficiently removes the hum noise. Now a days we use a high pass filter with a cutoff frequency of 10Hz and a low pass filter of 500 Hz which is recommended by SENIAM for surface electromyography.The ~2 Hz low pass filter is not a mistake either because it isn't really a low pass filter. It is part of the envelope detector circuit (fullwave rectified + LPF = envelope detector).

Raspberry Pi's don't have analog input pins so you'd need to use a ADC or an Arduino to convert it to a digital signal first

I'm not sure I understand your question about dividing the TL072 but both the INA106 and TL072 have min operating voltages of +-5V. I use +-9V in these instructions for simplicity because it is easily accomplished with two 9V batteries.

If you're wondering how I picked 2 Hz. See attached images. I felt it gave the best quality signal out of the other frequencies I tried and was a good match biomechanically to most of the muscle groups commonly targeted.

Standard first order RC LPF equation to get a cutoff frequency of ~2 Hz.

The 80.8kOhm resistors and the 1.0 uF capacitor form an envelope detector with a cutoff frequency of 2 Hz. An envelope detector is a low pass filter applied to a fullwave rectified signal.

Not sure I understand the question but you should follow the pictures as shown.

First order HPF. http://sim.okawa-denshi.jp/en/CRhikeisan.htm is a good site for quick reference w.r.t. filters. The cut off frequency is 106 Hz in this circuit. However, this cuts off a good deal of the EMG power spectrum so I would recommend using 10Hz or 20Hz instead. Keep in mind this this circuit is almost 10 years old and was created when I was just beginning my journey down the road of EMG circuitry.

Technically should be -110.The gain is found using the generic inverting amplifier gain equation G = -R2/R1R2 = 100kOhm internal resistor + 1 MOhm external resistor = 1100 kOhmsR1 = 10 kOhm internal resistorG = -1100 kOhm / 10 kOhm = -110

Frequency is usually between 10 and 500 Hz. Amplitude is usually between 2 and 10 mV.

The trimmer allows the gain to be adjusted. Using a normal resistor will make the gain fixed.

This is a single-channel EMG circuit same as the MyoWare.

Read through some of the other comments below. This question has been answered already.

Depends on what you mean by "work". You'll likely still get measurements but the accuracy will be degraded if you use 5% resistors. Those electrodes should work; you'll want to avoid TENS electrodes though.

The software is called Processing (Processing.org). You can find the code files on our GitHub repo.

Yeah that should work if you didn't damage the board when you burnt out the other pin.