- Summary
- Setup Raspberry PI
- Setup Arduino
- Design circuit board
- Assemble weather station
- Use weather station
- List of parts
This document describes the design, building and programming of an IOT enabled weather station. At regular intervals (eg. every 15 minutes) it measures a range of weather and other statistics, saving them as time stamped rows to an updated csv file. In particular:
- Temperature (C)
- Pressure (HPa)
- Humidity (%)
- Rainfall (mm/h)
- Wind speed (km/h)
- Wind direction (deg)
- CPU temp (C) - of the Raspberry Pi
- Current (A) - being drawn from the solar panel charged battery
- Voltage (V) - at the inputs to the circuits voltage regulator
- Power (W) - drawn by the weather station ( as A*V above)
This data can be remotely accessed via a php nginx web server interface from the Raspberry Pi, which also enables add-hoc contol and data requests. There is also a camera (attached to the Raspberry Pi) which can be controlled to take pictures on demand.
The hardware is based on a Raspberry Pi 3A+ and an Arduino Leonardo together with a Vero strip board that contains the Voltage Regulator and all other "glue" circuits. Everything is powered by a 12V 100Ah AGM Deep Cycle Battery which is charged by a 12V 150W Solar panel via a PWM Solar charge controller. The 12V input is regulated to 5.2V for the Raspberry Pi. This is is also used as required for charging the wifi modem, powering the Arduino (from the Raspberry Pi), powering sensors, servos and the digital relay.
The Raspberry Pi runs the web server and a python program that operates a bi-directional serial communications channel with the Arduino. The latter is ultimately attached to the various weather sensors. It also controls the digital relay used to time the charging of the wifi modem (on a 12hrs overnight ON and 12hr daytime OFF cycle) and the servo used to reset it (either by explicit command or each midnight). Control messages are typically sent from the Raspberry Pi via the serial channel to the Arduino (running a C++ program) which then returns sensor results or performs requested actions and returns confirmation messages.
The wifi modem and servo are attched by loomed 2 metre cables to the Vero board. The temperatue, pressure and humidity sensor is similarily attached with 1 metre cables. The two RJ11 terminated 3 metre cables from the rainfall, windspeed and wind direction sensors also attach to the Vero board. The Vero board circuit logic was designed in TinyCAD and its layout in VeeCAD.
We are using a Raspberry Pi 3 Model A+.
Details on how to set it up are given HERE.
We are using a Arduino Leonardo (Without Headers).
Details on how to set it up are given HERE.
DOWNLOAD and install TinyCAD if you don't already have it.
In addition we need the following files. They can reside in any directories (on the PC where TinyCAD is installed) when copied from here or recreated.
| File | Description |
|---|---|
| V_RomansOwn2020.TCLib | TinyCAD library file with needed custom symbols |
| WeatherStationMain1.dsn | Actual TinyCAD file for this projects circuit board |
| WeatherStationMain1.net | PCB netlist created in Protel format from above file |
Now install the above custom symbol library V_RomansOwn2020.TCLib from the main menu of TinyCAD: Library=>Libraries..=>Add=>V_RomansOwn2020.TCLib=>Open=>Ok
Finally we assume that all the generic TinyCAD and VeeCAD symbols libraries are installed and now we can open and view WeatherStationMain1.dsn with TinyCAD:
With the above *.dsn file loaded we can check and recreate (if we want to) the Protel netlist file WeatherStationMain1.net (mentioned above). To avoid warnings filter the checking options as follows:
Use Special=>Create PCB Net List...=>Export
DOWNLOAD and install VeeCAD if you don't already have it.
In addition we need the following files. They can reside in any directories (on the PC where VeeCAD is installed) when copied from here.
| File | Description |
|---|---|
| V_Standard_RMG.per | Custom VeeCAD shape library file |
| WeatherStationMain1.per | Vero Board circuit layout file |
Our ultimate goal is to have a valid circuit layout file to help us build the hardware. To view it we just need to open WeatherStationMain1.per in VeeCAD.
We can also modify or recreate it by pressing: Netlist=>Import=>Import with WeatherStationMain1.per open and dialog set to:
Below is the Weather Station concept diagram.
It was created using MS Visio Professional and the original Visio file WeatherStation.vsdx is available HERE for your perusal or modification.
The following is the best view of WeatherStationMain1.per in VeeCAD for building the Vero board circuit. It displays component designators and not values. Print it out 100% scale with the setups displayed below and stick it onto the track-free side of of an appropriately sized piece of Vero Board.
It is useful to print out a list of items (ie. designators) as shown below: Board=>Materials=>Components=>Print
The component designators/Items can be matched to the List of Parts below for soldering. Below are several images of the Vero circuit board during construction. Note that J12 is missing by mistake and was installed later.
Use WeatherStationMain1.dsn to wire everything up (pictured previously). Screw the boards with plastic spacers onto a Corflute (or other) base plate as displayed below:
Attach this to the base of a Corflute A4 sized weather proofed box. You will then need to drill four 10mm diameter holes in the base of the box in logically appropriate positions. These are needed for the wiring loom tubes. Doing so in the base is to avoid water ingress. The lid of the box is not shown, but it will need to be waterproofed with tape and eventually secured. The box itself will need to be waterproofed with tape.
The box is then placed on top of a milk crate, enabling the loom tubes to come out underneath. The Corflue box is then secured to the milk crate and the latter to the ground (in my case to a heavy wooden pallet).
A wateproofed (with silicon) glass or respex window must also be made in the box. This is used to mount the Raspberry PI camera in a waterproof way.
This sensor ADA2652 measures temperature, pressure and humidity. It is located in a sheltered waterproof above ground box and away from the Electronics Box. This ensures (hopefully) that it returns relevant/accurate measurements. The wires connecting it to the Vero Board circuit are limited to 1 metre to avoid any transimssion problems with the I2C protocol and are enclosed in a 10mm diameter wiring loom tube HP1225.
Its box is made of corflute and waterproofed with tape. The base is open to enable accurate measurements but keep rain and significant winds out. Note: P should be E below.
Examine the WeatherStation1.dsn diagrams [I2C SENSORS] section to see how the wiring should be connected. Note: The I2C data and clock lines should use shielded cable WB1506 while the power and ground can use light duty hookup wire WH3004. For connecting, solder eight halves from socket to socket jumper leads WC6026. We assume that the BME280 breakout board has a 7pin Header Terminal soldered to it (supplied):
These gauges SEN-15901 are supplied with an installation pipe, attachments and long wires terminating in male RJ11 connectors. One for the wind vane and Anemometer. The other for just the Rain gauge.
The wires attach to the Vero Circuit board through a hole at the base of the Electronics Box via a short length of 10mm diameter wiring loom tube.
Examine the WeatherStation1.dsn diagrams [HARDWARE DEBOUNCING & ANALOG INPUT] section to see how the wiring is connected.
This consists of a WifiModem and a Micro Servo YM2758. These are located in a sheltered waterproof above ground box and away from the Electronics Box. This keeps the electronics out of the rain, prevents problems due to condensation and allows positioning for optimal reception. This box is made of corflute and waterproofed with tape, just like for the BME280 sensor discussed previously.
The wires connecting to the Vero Board circuit are 2 metres long to aid positioning and are enclosed in a 10mm diameter wiring loom tube HP1225. They consist of power to the modem via a USB cable COU2AMB02 and three wires (Power, Ground and PWM) to the Servo. For the latter use light duty hookup wire WH3004 and solder three halves from plug to plug jumper leads WC6024 on the Vero board circuit side.
Examine the WeatherStation1.dsn diagrams [WIFI DONGLE POWER & CONTROL] section to see how the wiring is connected.
The servo is glued with araldite to the top of the wifi-dongle near its on/off button. When appropriately activated it presses the button (to shut down the modem or to restart it).
A Raspberry PI camera CE04421 is connected to the Raspberry Pi via a longer than standard 610mm cable ADA1731. Take care to attach the cable the right way around. It is then attached to the inside of the Electronics box using spacers HP0924, screws HP0924 and washers to a wateproofed (with silicon) glass or prespex window.
Photographs can be taken and accessed by the Weather stations web interface. See Access web interface.
Ultimately 12V power is supplied to the Vero board circuit in the Electronics box via two wires passing through a hole at the base of the Electronics Box enclosed in a short length of 10mm diameter wiring loom tube. Make sure to have the wires in the correct order.
Examine the [POWER CIRCUIT] section of the WeatherStation1.dsn diagram to see how the wiring is connected.
This power is supplied by a 150W Solar panel ZM9135 which includes a PWM Solar Charge controller which includes 5 metre leads. These are attached to a 12V 100Ah AGM Deep Cycle Battery SB1682 enclosed in a battery box HB8502 which is further enclosed in a large weighted down inverted plastic storage box.
For convenience the wires to the Electronics box are wired to a Marine Grade 10A Locking Lighter Plug PP1970, this being plugged into the battery box recepticle.
Once the weather station is running, it just sits there collecting weather data every 15 minutes and appending it to a csv file. It can be accessed and controlled via a web interface which is displayed below after the help command is submitted.
The other commands are for fun, maintenance or testing. Note for instance the tp command which takes and displays a photo with the Raspberry PI camera:
The most important command is gd which displays a link to the most recently updated weather data file SensorData.csv. This can be downloaded and conveniently formatted and displayed in an Excel workbook.
Through the magik of python and the "requests" module we are able to create an Excel workbook with a button activated macro that downloads, processes, formats and graphs the most recent data from the weather station. There is no need to explicitly access the data as shown above via the "gd" command.
We assume the latest version of Python3 has been setup on your PC. For example into the default directory: C:/Users/roman/AppData/Local/Programs/Python/Python39/.
All the necessary files are assumed to be located in the: C:/Users/roman/Documents/GitHub/WeatherStation/data directory and can be downloaded from:
-
HERE for SensorData.xlsm (needs Excel on PC to open)
-
HERE for SensorData.py (and detailed below)
import requests url = 'https://grobliro-device.dataplicity.io/' res = requests.get(url+'SensorData.csv') res.raise_for_status() print(res.status_code == requests.codes.ok) print(len(res.text)) print(res.text) sdf = open('C:/Users/roman/Documents/GitHub/WeatherStation/data/SensorData.csv','wb') for chunk in res.iter_content(100000): sdf.write(chunk) sdf.close()
The directories for these files are arbitrary as long as any references to them are adjusted in the SensorData.xlsm and SensorData.py files. Note: The SensorData.csv file is not need as it will be downloaded and is included in this repository as an EXAMPLE.
Apart from downloading the above two files you will need to install the "requests" module as follows:
-
Open the command terminal by running the Command Prompt App.
- You can find it by typing Command Prompt in the Search bar.
-
Now type the following and press the Enter key:
python -m pip install requests
-
If not already installed you should see something like this in the terminal window.
-
The directory from which you run the above is irrelevant.
Now you can open the Excel workbook SensorData.xlsm. Go to the "Graphs" tab and press the [FULL DATA UPDATE] button. See below:
This should download the most recent updated weather data file SensorData.csv and display the last 3.05 (in this case) days (as detailed in cell T9). You can change this up to "max days" (cell T7) and press the [PROCESS DATA] button to update the graphs. Note: Details might change, but will be logical and almost self explanatory.
Visible above is the first of four graphs. The others are placed below it and can be made visible by scrolling down (or pressing the "Page Down" button).
The "Data" tab contains the SensorData.csv data in columns A:K starting at row 2. These are processed/scaled in columns L:R and are displayed in some of the graphs.
The Macros reside in the "MyModule" module. Examine them for details and adjust the directories and/or file names in the global constant strings if necessary.
| Qty | Product | Description | AUD Cost | Comment | Designator____ |
|---|---|---|---|---|---|
| 1 | CE05971 | Raspberry Pi 3 Model A+ | $44.51 | Used for internet connection/control and storing collected data | connected to J2 and J8. Also camera attached |
| 1 | A000052 | Arduino Leonardo (Without Headers) | $39.00 | Used to interface all sensors | connected to J3, J5, J6 and J9 |
| 1 | XC4514 | Arduino Compatible DC Voltage Regulator | $7.95 | Converts 12V battery power to 5.2V for all weather station needs. Use 4 pins from 40 Pin Header Terminal Strip to attach its corners to Vero board | U1 |
| 1 | XC4486 | Arduino Compatible Logic Level Converter Module | $4.95 | enables bidirecional serial comms between Raspberry Pi and Arduino boards | B1 |
| 1 | ADA4226 | Adafruit INA260 High or Low Side Voltage, Current, Power Sensor | $22.51 | measures power and voltage used by total circuit. Attach to Vero board using supplied 8 Pin Header Terminal Strip | B2 |
| 1 | ADA2652 | Adafruit BME280 I2C or SPI Temperature Humidity Pressure Sensor | $45.02 | off board sensor used in shielded I2C mode | connected to J7 |
| 1 | SEN-15901 | Weather Meter Kit | $144.80 | passive reed switch based wind speed, direction and rain sensors | connected to J10 and J11 |
| 1 | BOB-14021 | SparkFun RJ11 Breakout ( currently only need 1 ) | $2.95 | contains below RJ11 Connector. Attach to Vero board using a 6 Pin Header Terminal Strip | J10 |
| 2 | PRT-00132 | RJ11 6-Pin Connector ( currently only need 1 ) | $3.78 | attaches to above breakout board | |
| 1 | SY4058 | 6V DIL SPDT Mini Relay | $7.95 | used to control charging of Wifi Modem | U2 |
| 1 | YM2758 | Arduino Compatible 9G Micro Servo Motor | $11.95 | used to "manually" reset Wifi Modem, connect with three 2M lengths of hookup wire | connected to J4 |
| 1 | CE04421 | Raspberry Pi Camera Board v2 - 8 Megapixels | $38.95 | just for interest | connected to cable below |
| 1 | ADA1731 | Flex Cable for Raspberry Pi Camera - 610mm / 24" | $6.66 | longer than standard cable for flexibility | connected to Raspberry Pi and camera |
| 1 | SN74HC00N | Logic IC, NAND Gate, Quad, 2 Inputs, 14 Pins, DIP, 74HC00 | $0.61 | part of hardware debounce circuit for wind speed and rain sensors | connected to U5 |
| 1 | SN74HC14N | Logic IC, Inverter, Hex, 1 Inputs, 14 Pins, DIP, 74HC14 | $1.03 | part of hardware debounce circuit for wind speed and rain sensors | connected to U4 |
| 2 | PI6501 | 14 Pin Production (Low Cost) IC Socket | $0.80 | part of hardware debounce circuit for wind speed and rain sensors | U4, U5 |
| 1 | RR0596 | 10k Ohm 0.5 Watt Metal Film Resistors - Pack of 8 ( only need 3 ) | $0.85 | part of hardware debounce and input circuit for Weather Meter Kit sensors | R3, R5, R6 |
| 1 | RR0572 | 1k Ohm 0.5 Watt Metal Film Resistors - Pack of 8 ( only need 3 ) | $0.85 | used in hardware debounce and relay circuits | R1, R2, R4 |
| 1 | ZT2152 | BC547 NPN Transistor | $0.30 | used in relay circuit | Q1 |
| 1 | ZR1004 | 1N4004 1A 400V Diode - Pack of 4 ( only need 1 ) | $0.98 | used in relay circuit | D1 |
| 2 | MCCB | Tantalum Capacitor, 0.1 µF, 35 V, MCCB Series, ± 20%, Radial Leaded, 5.08 mm | $4.34 | used in hardware debounce circuit for wind speed and rain sensors | C1, C2 |
| Qty | Product | Description | AUD Cost | Comment | Designator____ |
|---|---|---|---|---|---|
| 1 | HP9544 | PC Boards Vero Type Strip - 95mm x 305mm | $12.95 | Contains all circuits apart from Raspberry Pi and Arduino | |
| 1 | WW4030 | Tinned Copper Wire - 100 gram Roll | $19.95 | for wiring up above Vero board | |
| 5 | HM3414 | 4 Pin 0.1 Straight Locking Header - 2.54 pitch - Single | $2.00 | On Vero board to connect to Raspberry Pi, Arduino and BMP280 sensor | J2, J3, J7, J9 |
| 6 | HM3412 | 2 Pin 0.1 Straight Locking Header - 2.54 pitch - Single | $2.40 | On Vero board and Arduino for interconnection | J5, J6, J8 |
| 1 | HM3413 | 3 Pin 0.1 Straight Locking Header - 2.54 pitch - Single | $0.40 | On Arduino for connection to Vero board circuit | |
| 3 | HM3172 | 2 Way PCB Mount Screw Terminals 5mm Pitch | $4.05 | On Vero board for external connections to 12V power, Raspberry Pi and wind direction sensor | J1, J11, J12 |
| 1 | HM3173 | 3 Way PCB Mount Screw Terminal - 5mm Pitch | $1.75 | On Vero board for external connection to Wifi Modem switching servo | J4 |
| 1 | PS0916 | USB TYPE A PC MOUNT Socket | $2.95 | on Vero board for power to Wifi Modem | U3 |
| 1 | HP0924 | M3 x 12mm Tapped Nylon Spacers - Pk.25 ( only need 14 ) | $9.95 | For mounting Vero board, Raspberry Pi, Arduino and camera | |
| 1 | HP0430 | 3mm Flat Steel Washers - Pk.25 ( only need 12 ) | $3.00 | as above | |
| 1 | HP0440 | M3 x 5mm Black Equipment Screws - Pk.25 ( only need 14 ) | $2.30 | as above | |
| 1 | HP0403 | M3 x 10mm Steel Screws - Pk.25 ( only need 12 ) | $3.00 | For mounting Vero board, Raspberry Pi and Arduino | |
| 1 | HM3212 | 40 Pin Header Terminal Strip ( only need 4 pins ) | $1.10 | for mounting power circuit XC4514 | |
| 1 | WC6026 | 150mm Socket to Socket Jumper Leads - 40 Piece ( only need 20 ) | $5.95 | for connecting Vero board circuits to Raspberry Pi and Arduino | |
| 1 | WC6024 | 150mm Plug to Plug Jumper Leads - 40 Piece ( only need 3 ) | $5.95 | for connecting Vero board circuits to Servo and other external sensors | |
| 1 | WC7723 | 0.5m USB A male to Micro-B Cable ( can be 0.25m ) | $5.95 | To power Arduino from Raspberry Pi USD port | |
| 1 | WC7757 | USB A to USB Micro B Cable 150mm | $4.95 | To power Vero board circuit from Raspberry Pi (USB not needed) |
| Qty | Product | Description | AUD Cost | Comment |
|---|---|---|---|---|
| 1 | PP1970 | Marine Grade 10A Locking Lighter Plug | $7.95 | Used to get 12V power from Battery Box |
| 1 | WH3057 | 7.5 Amp 2 Core Tinned DC Power Cable - 3 metre | $4.80 | Connects above to main vero circuit board |
| 1 | SB1682 | 12V 100Ah AGM Deep Cycle Battery | $299.0 | stores all power for this weather station |
| 1 | ZM9135 | 12V 150W Folding Solar Panel with 5M lead (discontinued) | $169.00 | used to charge above battery - has controller |
| 1 | HB8502 | Battery Box with Voltmeter and USB Charge | $99.95 | keeps battery safe and conveniently accessible |
| 1 | WH3000 | Red Light Duty Hook-up Wire - 25m ( only 3 metres needed ) | $5.95 | used for attaching external sensors/servo |
| 1 | WH3001 | Black Light Duty Hook-up Wire - 25m ( only 3 metres needed ) | $5.95 | used for attaching external sensors/servo |
| 1 | WH3004 | Yellow Light Duty Hook-up Wire - 25m ( only 2 metres needed ) | $5.95 | used for attaching external sensors/servo |
| 1 | WB1506 | FIG 8 - OFC Shielded Audio Cable - Sold per metre - 1 metre ) | $4.95 | used for attaching external I2C sensor |
| 1 | HP1225 | 10mm Loom Tube - 10 metres ( only 4 metres needed ) | $18.95 | keeps wires to external sensors and wifi dongle secure |
| 1 | WifiModem | Telstra 4GX Wi-Fi Pro | $120.0 | connects weather station to the internet |
| 1 | COU2AMB02 | USB A to Mini-B 2M Cable | $14.88 | power to above wifi dongle from Vero board power circuit |