I am a new user, so first of all I want to say hi to everyone!
A few weeks ago I launched two smog sensors: one with a dryer for high humidity conditions, the second one without a dryer. I want to collect measurements to try to replace the heater with the software solution (mainly I want to test machine learning).
I am looking for datasets with the same solution (two sensors, with- and without dryer) to compare results and extend my own dataset, which won’t have enough data until next year. Maybe someone has such a set and can share it or knows where to find them? I have seen a few publications on Researchgate, but the data are nowhere to be found and contact with the authors is difficult.
Thanks for your help!
We have just set up a heated smog sensor and have two of the Nettigo unheated kits that are produced specifically for the Sensor Community. All three are co-located. We are noticing a variation between all three SDS011s. I have yet to analyse the data fully to determine if it is more than the 5% that is expected. Are you running the unheated smog sensor with the Nettigo board? Our data from the SDS011 on the Nettigo heated system reads lower than anticipated even at low humidity. The data is interesting and I shall post more in this forum later. There are quite a few scientific papers out there I particularly like Laquai et al https://www.researchgate.net/publication/351245900_Comparison_of_a_Computational_Method_for_Correcting_the_Humidity_Influence_with_the_Use_of_a_Low-Cost_Aerosol_Dryer_on_a_SDS011_Low-Cost_PM-Sensor
They discuss the need for a calibration with a reference sensor and to check the humidity of the particle chamber. I don’t know if this fits with your machine learning but it seems that heating isn’t the full solution to the inaccuracies at high humidity, but it could be a start .
I hope this is helpful.
Thanks for your reply. My smog sensors are Nettigo Air Monitor with slight changes and own software. SDS011 sensors reading are indeed different even at low humidity but the difference is probably small enough.
I know the publication by Mr Laquai and Ms Kroseberg, also I was looking for a contact and dataset of twin-SDS011 box, but I have no information on this
From the paper; I am not sure if the twin system was run for a very long time. You could contact the lead for the group in Stuttgart (https://www.ifk.uni-stuttgart.de/en/institute/team/Vogt-00002/.)
I recently posted here our preliminary results from our three sensors and, unfortunately for us, the variation between the sensors is quite large (looks like about 40%) this should be sorted out with a calibration factor. However, we do not have a reference system so I am assuming an average of the three (below 70% humidity) gives the most accurate value of actual PM2.5.
Clearly, like you we are just starting out with the heated system but we would be happy to share our data with you if it would be helpful. Perhaps check out my last post first as our information might not be suitable for your purposes.