We have some queries regarding the following:
- How can we extract the data result of swarm in an excel format using velocity (m/s), acceleration(m/s2) and time? Our main objective is to get the elastic response spectra.
- In the 1st plot of swarm(waveform), what is the unit that the “count” represents? Is it a velocity form in m/s unit?
- In the 2nd plot of swarm (power spectra), what is the unit and can you further explain how can we get the acceleration in this plot?
- What is the difference between EHZ, ENZ, ENN, ENE? What does the “samples per second” mean?
- In the RS community, how can we identify the location of other countries by using the swarm?
Good day RBS,
Regarding the usage of SWARM to achieve the results you desire, we recommend to write to the USGS since SWARM is their proprietary software: USGS: Volcano Hazards Program
However, it is possible to extract the data from a Shake via Python using the Obspy package (https://docs.obspy.org/). A sample basic code to convert data in acceleration (m/s2) is provided in our manual here Developer’s corner — Instructions on Setting Up Your Raspberry Shake and it can be used as a starting point.
Counts is a unitless number that represents an analogue for the amount of voltage on the circuit of the given channel at the given time. More informations here: IRIS: Frequently Answered Question
As per question 1, we encourage you to contact them for these details. Also, the documentation of SWARM can be useful if you haven’t already perused it: https://volcanoes.usgs.gov/software/swarm/doc/swarm_v3.pdf
It has been already answered here: Direction of Earthquake & Location of Device - RS4D - #2 by Stormchaser
You can also see the locations of the Shakes in our network via our Shakenet https://shakenet.raspberryshake.org/ or StationView pages https://stationview.raspberryshake.org/.
If SWARM is strictly needed instead, you can add the entire RaspberryShake network by creating a “New Data Source” in the “Data Chooser” window, and adding these two values in the two URL fields of the FDSN WS tab, and then clicking on the Update button.
After this has been done, it is possible to visualize a map by opening the “Window” menu and clicking on “Map”.
Just to amplify on what Stormchaser has said about SWARM:
To get units (m/s or m/s2) in SWARM, you go to:
Helicorder View Settings (2nd icon)
Use Calibrations - tick it
You can extract data from SWARM by saving your sample to the clipboard, then in Clipboard, click Save All Waves (3rd icon). You will be given a list of formats, most of which are binary, but there’s also “Matlab-readable text file”. This file can be imported into Excel. It has time in the first column in millisecs from 1/1/1970.
Good day sir.
Thank you for your response in our queries. We already follow your advise regarding the extract of data from raspberry to python/obspy. However, we did not came up with a good result.
Can you please help us regarding this? We are a structural engineer that aim to get the response of the earthquake so that we can input that data to our analysis in the building.
Attached is the data from the raspberry.
.RASPBERRY.zip (49.0 KB)
Regarding the detailed task that you are asking us, this would be part of paid technical support. I then encourage you to contact us at email@example.com so that we can offer you a quote, if you are still interested.
We look forward to working with you. Please let us know via email how you would like to proceed.