DMS Air Monitor Group Project

Brandon_Green · August 22, 2016, 10:21pm

Here is a google sheet with the last week of data in it, it is interesting to look at the timeline view to estimate how often areas like woodshop are in use, it looks like roughly 40-50% of the time, 1,109 samples(each of a 4 minute period) indicate sound levels over background noise out of 2,805 samples

wandrson · August 22, 2016, 10:30pm

[quote=“Brandon_Green, post:42, topic:11106”] …
to estimate how often areas like woodshop are in use, it looks like roughly 40-50% of the time …
[/quote]

We spend an awful lot of money on a shop that is not being used 60% of the time…

Ducking now…

mkart · August 22, 2016, 10:32pm

I think the graph looks more like 61% of the time in use.

Brandon_Green · August 22, 2016, 11:58pm

Would probably be more informative to calculate a percentage that doesn’t include midnight - 8am

rshill · August 23, 2016, 4:00am

I’d be more interested in how it compares to other areas than the raw percentage.

Brandon_Green · August 23, 2016, 4:52am

I created a sheet with the data very roughly aligned (each is sampling just based on each pis independent clock and how long it takes to post, so have to go back and align data taken during the same 4 minute period), and it is too noisy to immediately see much. Other than that the wood dust collector is picked up by the metalshop mic, and the AC turning on and off during the night is picked up by all of them.

(Axis is db, which is a logarithmic scale)

Brandon_Green · September 6, 2016, 7:13am

Part of the original goal of this project was to quantify if the woodshop air is too dusty(hazardous), turns out the dust collection and continuous filtering keeps woodshop air pretty good.

But metalshop often pegs the 10 micron particulate sensor at 2k ug/m^3 if someone is grinding or cutting for long periods of time( as was case Monday). Exposure to over 150 ug/m^3 average for a work day is considered a risk.
https://m2x.att.com/d/7a8c0ddb57d5afee446c8ec052427ab6

ChadB · September 6, 2016, 6:28pm

@Brandon_Green I heard there was a request to the Science committee to provide some baseline calibration of the particle sensors. Do you have more information about what’s needed?

mattarmstrong · September 7, 2016, 3:56am

@Brandon_Green My bad on Monday
Didn’t realize till I got home and did the old fashioned air quality test… Clearing the sinuses

Definitely came back with my mask and was curious why we don’t have a filter in there too

NightRanger · September 8, 2016, 1:51pm

will you please zoom in on the data from 7:00-7:30? what was the date when this was taken

Brandon_Green · November 21, 2016, 6:56pm

Just realized that the woodshop sensor has been offline for 29 days, can anyone see if it is still there? Did it get unplugged?

eric24 · February 28, 2017, 4:08pm

@Brandon_Green: I’m late to the party, but I’m interested in your air quality project. I’m working on a related IoT project, namely a platform for data management and visualization, and I’m looking for use-cases that I can run through the platform. I see you’re using AT&T’s M2X service, and I’m wondering if I might get access to the data feed (not sure what protocols are supported, but we can handle just about anything–MQTT, CoAP, WebSockets, REST, etc.). If the raw feed is available, I’d like to use it to build a use-case/demo, which you are welcome to use, too.
–Eric

Brandon_Green · February 28, 2017, 7:09pm

Right now it’s just posting json to a rest endpoint every 4 minutes

github.com

brandonagr/gom2xlogger/blob/v2/gom2xlogger.go

package main

import (
	"encoding/json"
	"fmt"
	"log"
	"math"
	"net/http"
	"os"
	"strings"
	"sync"
	"time"

	"github.com/cocoonlife/goalsa"
	"github.com/tarm/serial"
)

// #cgo LDFLAGS: -ldht
// #include "/home/pi/Adafruit_Python_DHT/source/Raspberry_Pi_2/pi_2_dht_read.h"
import "C"

This file has been truncated. show original

The data should be publicly available on M2X, if you create an account you should be able to query the api to get the values at a url like
https://api-m2x.att.com/v2/devices/53665d82ee2f34a0febfae20cc75b1bf/streams/SDS021_PM10/values

Or could also push an update so the devices are sending data to another rest endpoint as well as m2x

The labels on dallas.ms/air are clickable and go to the m2x device pages (these pages have been slow to load lately)
https://m2x.att.com/d/7a8c0ddb57d5afee446c8ec052427ab6
https://m2x.att.com/d/0349cdda9597ff4a8f1d5773c0d1859b
https://m2x.att.com/d/8c4a161db98defdff594c42b91151c3f
https://m2x.att.com/d/53665d82ee2f34a0febfae20cc75b1bf

eric24 · February 28, 2017, 10:24pm

Perfect! I’ll query the data from M2X for now. Maybe in the future, we can explore some other data uplink options. I’ll work on some quick dashboards. In the mean time, if you have any ideas on visualizations or analytics you’d like to see, let me know.

eric24 · March 4, 2017, 3:34pm

@Brandon_Green: Question about the dB value that’s being reported: I this is the raw sound pressure level (SPL) in the room, referenced to the standard reference amplitude of 20 microPascals = 0 dB? Or has it been “weighted”, as dB(A) or dB©?

Brandon_Green · March 4, 2017, 7:48pm

It’s the arbitrarily calculated root mean square of the value coming off the mic shifted to look like a plausible DB level. It’s not calibrated at all, so the values really don’t have a unit and can only be reasonably compared to values from the same sensor. Such as telling it’s now louder in woodshop so the dust collector is probably running.