Main findings
When compared to official, highly accurate sensors, the low cost sensors followed various trends:
A relatively high correlation between timeseries.
![](https://uploads-ssl.webflow.com/5a91a514b87f26000187aee4/5f68b53ca43dd93c4e7827d1_graph1_3x.png)
A considerable underestimation of absolute rainfall rates, leading to...
![](https://uploads-ssl.webflow.com/5a91a514b87f26000187aee4/5f68b53d25448cbf189118ac_Graph2_x3.png)
... overlooking some peak rainfall events.
![](https://uploads-ssl.webflow.com/5a91a514b87f26000187aee4/5f68b53b4637b9c35f7eb2f1_Graph3_x3.png)
A relatively high correlation between timeseries.
![](https://uploads-ssl.webflow.com/5a91a514b87f26000187aee4/5f68b53ca43dd93c4e7827d1_graph1_3x.png)
A considerable underestimation of absolute rainfall rates, leading to...
![](https://uploads-ssl.webflow.com/5a91a514b87f26000187aee4/5f68b53d25448cbf189118ac_Graph2_x3.png)
... overlooking some peak rainfall events.
![](https://uploads-ssl.webflow.com/5a91a514b87f26000187aee4/5f68b53b4637b9c35f7eb2f1_Graph3_x3.png)
The gathering of data using the low-cost sensors was complicated in multiple ways:
![](https://uploads-ssl.webflow.com/5a91a514b87f26000187aee4/5f68d5a57a650d6162d47de0_sensors_placement2.png)
- new sensors still faced BATTERY ISSUES during winter.
- In an URBAN CONTEXT, the installation of low-cost sensors is challenging.
> it is crucial to limit obstruction by neighbouring objects as well as to
favorize a S-SW orientation.
> The placement of one personal, LoRa gateway per sensor helps overcoming connectivity issues and loss of data packages in urban contexts.
=> CONCLUSION: technology not mature yet