JQ03a-21 Electromyography based fitness monitoring device

Subscribe
Notify of
9 Comments
Inline Feedbacks
View all comments
WONG, Man(@eemwong)
January 19, 2022 3:39 pm

Hi. Is the 50 Hz powerline noise filtered somewhere along your signal amplification and filtering chain?

LO, Ho Hung Charlie(@hhclo)
January 19, 2022 3:46 pm
Reply to  WONG, Man

Hi. We are not going to use notch filter in our filtering chain. We use Driven right leg circuit to minimise the powerline interference instead. Because using notch filter will affect the frequency components around 50 Hz.

LUI, Ka Lung(@klluiaf)
January 19, 2022 3:46 pm
Reply to  WONG, Man

First, this device is designed to be battery operated so there is not much direct AC noise.

As for the 50Hz AC coupling effect on the human body, the high CMRR(~90-110dB) in the instrumental amplifier should mitigate the effect.

In case this CMRR is insufficient in blocking the AC noise, we’ve also designed an optional DRL circuit that can inject the inverted common-mode signal to the user to mitigate AC noise

There is also an option to use a software notch filter, but it destroys too much data in the major EMG range(25-125Hz), we’ve since given up that option

QUADEER, Ahmed Abdul(@eeaaquadeer)
January 19, 2022 3:12 pm

Interesting project.

There are some formatting issues but the problem and the proposed solution is described well in the poster. I have a few questions:

Has non-invasive detection of EMG signal ever done before?

Once successful, can this technology be incorporated in existing sport tracking devices like Apple Watch?

LUI, Ka Lung(@klluiaf)
January 19, 2022 3:17 pm

non-invasive detection of EMG has been done on-device before
like MYO-armband that uses EMG to detect hand guesture
A video of the concept:https://www.youtube.com/watch?v=jOEcsNmTk7g

However, wrist-worn EMG sensor(i.e. incorporating EMG sensor on to Apple watch) might have signal issues as we don’t have much muscle on the wrist

Therefore, we propose our device to be worn on places with large muscle group like bicep

LO, Ho Hung Charlie(@hhclo)
January 19, 2022 2:39 pm

Hi everyone, View this PDF instead

QUADEER, Ahmed Abdul(@eeaaquadeer)
January 19, 2022 3:12 pm

This link is not working.

WONG, Kiu Fan Kelvin(@kfkwongaa)
January 19, 2022 3:15 pm