1 / 17

Exploring Gastric Electrical Activity with Phasors and Capacitors in Low Pass Filter Applications

This article delves into the application of phasors and capacitors in analyzing gastric electrical activity using electrogastrograms. Gastrointestinal disorders affect 60-70 million people, emphasizing the importance of understanding electrical signals in the gut. We explore how slow wave mapping, recorded through a flexible electrode array of 256 electrodes, tracks the spread of electrical activity in the stomach while filtering out noise. By implementing low pass filters, we can improve the clarity of critical signals and their magnitude, fostering advancements in gastrointestinal health monitoring.

meriel
Télécharger la présentation

Exploring Gastric Electrical Activity with Phasors and Capacitors in Low Pass Filter Applications

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Phasors and Capacitors Spin My World Right Round

  2. LPF Application: Gastric Electrical Activity • 60-70 million people suffer from GI disorder • Electrically active organ http://www.virtualmedicalcentre.com/anatomy/gastrointestinal-system/7

  3. Electrogastrogram and Slow Wave mapping Flexible Electrode Array (256 electrodes) Recording the EGG (6 electrodes) Typical gastric slow wave recording (freq ~ 0.05 Hz) Slow wave map tracks spread of electrical activity

  4. Noise corrupting the recording Signal of interest Noise (oscillations so fast you can’t see the individual waves) What the electrode records (ruh-roh!)

  5. Graphical Representation of Cosines w Blue = Vin(t) Red = VC(t) Green = VR(t)

  6. Describing a cosine wave with phasors 4.33 2.5 0 5

  7. How about a sine wave?

  8. Phasors! -sinwt coswt -coswt sinwt Rotates in time But we just read off the magnitude and phaseinformation

  9. Red vs. blue: What’s different? 1. Magnitude 2. Phase

  10. All shapes and sizes… Typical ones you’ll find in the lab Some big and some small…

  11. These are capacitors too! Cell membrane Icky cells (bacteria)

  12. And so is this! PC board Red = top layer Green = bottom layer

  13. Implementing a low pass filter (LPF) Strongly attenuated 60Hz Barely attenuated 0.05Hz

  14. 60 Hz signal zoomed in f

  15. Raw vs. Filtered Signal

  16. Low Pass Filter Example: Vout and Vin

  17. Vout, Vc, and VR

More Related