Project Overview

The main objective of this project is to develop an instrument to monitor and record seismic activity using low-cost electronic components and open-source software. Additionally, the design of the instrument is intended to help explain and demonstrate instrumentation in seismology, which can be used for educational and outreach purposes.

The inception of this project started at the University of the West Indies Seismic Research Center (UWI SRC) as a means of developing in-house seismic instrumentation at a low cost to enhance the monitoring network. After multiple iterations, a final prototype has been developed and is currently being used at the Montserrat Volcano Observatory (MVO) for education and outreach purposes. The aim is to explain and demonstrate the process of instrumentation in seismology, essentially illustrating how ground motion is translated into digital seismic signals displayed on monitors.

Brief Design Overview

Sensor

Three SM-24 geophones were used to detect ground motion. These geophones have a 4.5Hz natural frequency and were oriented in North-South (NS), East-West (EW), and Vertical (Z) directions.

Signal Conditioning

The output from each sensor is connected to a signal conditioning circuit board, which amplifies the low amplitude signals and filters out unwanted frequencies. The signal conditioning circuit includes a non-inverting amplifier with a gain of 120 and a 50Hz low-pass filter. The circuit board is mounted inside the sensor enclosure.

Digitization

The digitization of analog signals from the sensors to digital signals is managed by the digitization board consisting of three ADS1220 24-bit analog-to-digital converters (ADC). An Arduino Mega microcontroller collects the data and sends it via USB serial to a Raspberry Pi (RPi) microcomputer for processing.

Data Processing

A RPi microcomputer processes the incoming data from the Arduino microcontroller. The process involves reading data from the USB serial, converting it to 512-byte Mini-SEED (MSEED) records (a standard for the exchange of earthquake data), and buffering the records into a ringserver. MSEED is a standard open-source seismological data format. The data is stored locally on the RPi, either on disk or a connected USB flash drive, in one-hour MSEED files.

When connected to the internet or a network, the instrument can stream data in real-time, which can be collected remotely.

Enclosure

The sensor components (geophones, signal conditioning board) and digitizer components (digitizer board, RPi, Arduino, power board) are stored in outdoor electrical weatherproof enclosures. Connections to outside components such as GPS, and power supply use circular industrial waterproof connectors.

Education and Outreach

How is the project being utilized in education and outreach at MVO? We present the instrument at most events attended by the MVO, particularly during school visits. Recently, the MVO participated in the STEM fair and exhibition during National STEM Week, where the instrument was showcased to interested students and other attendees. We explained the instrument’s functionality and operation, highlighting key features in instrumentation and seismology. A display showed data streaming from the instrument, and students were encouraged to jump up and down to simulate an earthquake, observing real-time changes in the signal. Demonstrating the instrument at various events provides a valuable learning opportunity, especially for students interested in STEM fields.

Conclusion

This project demonstrates the feasibility of using low-cost electronic components and open-source software to develop a seismic data acquisition system. The final prototype, now in use at the Montserrat Volcano Observatory, not only aids in monitoring seismic activity but also serves as an educational tool to explain the principles of seismological instrumentation. This system represents a significant advancement in making seismic monitoring accessible and understandable to a broader audience.

Contact

To learn more about this project, please contact Arvid Ramdeane.

Email:
arvid@mvo.ms

Phone:
1-664-491-5647 Ext 435 (work)
1-664-495-1122 (mobile)