Chapter 5: Building a Weather Station

In this chapter, you will build a weather station to conduct your own citizen science experiments using Raspberry Pi Pico. We will discuss interfacing and testing various sensors with the Pico and installing your Pico outdoors.

By the end of this chapter, you will have built something similar to what is shown in the following figure:

Figure 5.1 – Raspberry Pi Pico interfaced to a weather station

In this project, we will discuss interfacing sensors with the Pico to collect environmental data from the immediate surroundings. We will test all the sensors by discussing the code needed to interface them and put our weather station together.

The topics covered in this chapter will include the following:

• Conducting citizen science experiments
• Installing the requisite libraries
• Testing the sensors
• Assembling and testing the weather station

  Weatherproofing Your Project

  In this chapter, we want to...

Technical requirements

The following hardware is recommended for this chapter. We will leave it up to you to select the sensors for your weather station:

• Raspberry Pi Pico (https://bit.ly/3AJtoAf) – $4
• Pico Omnibus – Dual Expander (https://bit.ly/3sr2GJR) – $10.50
• Encased I2C Temperature/Humidity Sensor (https://bit.ly/3FNFWdr) – $29.95
• 2 x RJ11 breakout board (https://bit.ly/3AS6OVQ) – $6.99
• VEML6075 UV Sensor (https://bit.ly/2YYKPQ4) – $7.50
• BME280 Pressure Sensor (https://bit.ly/3lPb3xh) – $14.95
• Adafruit STEMMA Soil Sensor (https://bit.ly/3iQtq3r) – $7.50
• Weather Meter Kit (optional) (https://bit.ly/3johPZC) – $79.95

The code samples discussed in this chapter are available here:

https://github.com/PacktPublishing/Raspberry-Pi-Pico-DIY-Workshop/tree/main/chapter_05

Code in Action videos for this chapter can be viewed at https://bit.ly/3P1uTSz.

Conducting citizen science experiments

Citizen science is a broad approach that involves numerous individuals and groups who volunteer to collect and/or analyze data on various projects that are of wide interest. Participants in these projects may be of any gender, age group, and educational background, and they may span across continents. Some common areas where citizen science can be effective include weather and climate monitoring, wildlife tracking, and related areas. Applications include general science, sustainability, climate change, population health, and smart cities. It is expected that the nature, scope, and number of citizen science endeavors will grow immensely in years to come. The types of data gathered by citizen science may include discrete or continuous parameters such as temperature, Volatile Organic Compounds (VOCs), and other atmospheric content, images, and audio files.

At scale, citizen science projects can be effective at helping solve large-scale data-intensive...

Installing the requisite libraries

We are going to install all the libraries required for this chapter. The first step is to download the CircuitPython Library Bundle. You can download the Library Bundle as a ZIP file from here: https://circuitpython.org/libraries.

Extract the contents of the ZIP file to get started with the library installation.

CircuitPython Installation

We are assuming that you have installed CircuitPython on your Pico. If you are not familiar with the installation process, we recommend following the installation process from Chapter 1, Getting Started with Raspberry Pi Pico.

The AM2315 sensor

We need two libraries for the AM2315 temperature (shown in the following figure) and humidity sensor, namely adafruit_bus_device and adafruit_ahtx0. In the extracted bundle, there is a folder called adafruit_bus_device along with the adafruit_ahtx0.mpy file. Copy over the folder to the lib folder of the Pico.

Library Selection

According to the guide...

Testing the sensors

In this section, we will set up and test the individual components used in the project before we put them together.

Testing the BME280 sensor

In this section, we will test the BME280 sensor (as shown in the following screenshot):

Figure 5.2 – The BME280 Pressure Sensor

The BME280 Pressure Sensor can be used to measure temperature, humidity, and atmospheric pressure. It comes with an I2C interface, and its address on the I2C bus is 0x77.

The sensor is interfaced to the Pico, as shown in the following schematic:

Figure 5.3 – The Fritzing schematic for the BME280 sensor

In the preceding schematic, the sensor is interfaced to the Pico as follows, where the left side of the arrow refers to a pin on the BME280 breakout board, while the right side of the arrow refers to a pin on the Raspberry Pi Pico:

• VIN → VBUS
• SCL → GP9
• SDA → GP8
• GND

  Pull-Up Resistors for...

Assembling and testing the weather station

We recommend following an excellent guide from SparkFun to assemble the kit. You can refer to the guide here: https://bit.ly/3yTgZZu. We assembled our kit and tried setting it up in our backyard, as shown in the following figure. We made use of a Pico and a weather carrier board for our installation. This is just for the sake of convenience to avoid some messy wires outdoors:

Figure 5.18 – A weather station installation in the backyard

We tested our weather station without the following considerations:

• A power source for the weather station
• Assembly of the carrier board onto the weather station
• Weather-proofing the carrier board inside an enclosure
• Sturdy installation of the weather station

It is going to take some extensive testing to identify and fix all the problems. The first step is to fix any problems associated with sensor interfacing. Then, we need to ensure that any enclosure...

Summary

In this project, we discussed conducting our own citizen science experiment by building our own weather station using the Raspberry Pi Pico. We tested the sensors and put the weather station together. We also discussed troubleshooting problems associated with deploying the station outdoors, and we also discussed weather-proofing our installation.

Since citizen science experiments benefit from sharing data on publicly available data streams, we plan to make our data available once we have added connectivity to our weather station. We also plan to publish the status of our weather station to a public data stream.

In the next chapter, we are going to have fun with displays!