Description

'Tis the season to be jolly, but sometimes you would like to tone down the jolliness. Or perhaps you are the designated driver and need to know how festive that punch is !
I have the perfect solution for you:

Most people look to buy this sensor to make their own DIY breathalyser. Don't bother. You won't get the accuracy you are looking for, or you probably won't have all the necessary equipment/materials required to calibrate it. While you can get a rough idea, I would NOT recommend using this sensor to make any decisions based on quantitative measurements.

I will also point out that this sensor is not specific for Alcohol. It will react to some other chemicals too. In other words, you cannot assume that a positive result equates to the presence of alcohol (ethanol) in the air. It could be butane, LPG, Isopropanol etc etc.

This project will attempt to show how much alcohol is in the air, for the sole purpose of identifying the presence, as well as getting a rough estimate of the strength of alcohol, in a variety of festive drinks.

PLEASE NOTE:
Do not submerge the sensor in liquid, and avoid splashing the sensor. Also do not expose the sensor to strong chemicals (including alcohol) for extended periods. There is a 48 hour burn-in time for this sensor. Which means that it actually performs better once it has been used for over 48 hours. The sensor also needs to warm up, which often takes more than 15 minutes long. Once exposed to a strong concentration of alcohol in the air, the sensor takes what seems like an eternal amount of time to recover. Take this into consideration when planning your future project.

Parts Required

1. Arduino Uno (or compatible board)
2. Grove Base Shield (v2)
3. Grove Alcohol Sensor
4. Grove 16x2 LCD (White on Blue)
5. Grove Universal 4 pin buckled cable: one supplied with each module.
6. USB cable - to power and program the Arduino
7. Battery pack / Power bank

More information about the Grove Modules can be found here:

• Grove Alcohol Sensor Wiki
• Grove 16x2 LCD Wiki
• Grove Base Shield V2 Wiki

The Grove Base shield has 14 pins on the Analog side, and 18 pins on the digital side. Check the number of pins on your Arduino UNO (or compatible board) to ensure the shield will sit nicely on top. NOT compatible with Arduino boards that have the Arduino Duemilanove pin header layout.

Arduino IDE

While there are many Arduino IDE alternatives out there, I would recommend that you use the official Arduino IDE for this project. I used the official Arduino IDE app (v1.8.5) for Windows 10.
Make sure to get the most up-to-date version for your operating system here.

Connection instructions

Now that the code has been uploaded, it is now time to make the necessary connections from the Arduino to the Grove 16x2 LCD module, and also to the Grove Alcohol sensor.

1. Disconnect the USB cable from the Arduino to remove power.
2. Install the Grove Base Shield (v2) onto the Arduino UNO. The header pins on the Base shield should line up exactly with female headers of the Arduino. Please make sure that there are no stray or misaligned pins that are unaccounted for by the Arduino board.
3. Set the Base Shield Switch to 5V. The switch is in the corner near the LED on the Base Shield.
4. Connect one end of the 4-pin cable to A0 connector on the Grove Base Shield, and the other end of the cable to the Grove Alcohol Sensor module.
5. Connect one end of a 4-pin cable to an I2C connector on the Grove Base Shield, and the other end of the cable to the Grove 16x2 LCD module.
6. You can now apply power to the Arduino Board via the power jack or the USB cable.

Connection Table

Arduino to Grove Alcohol Sensor module

The Grove Alcohol sensor operates off 5V.
If you are using the Grove Base Shield, place the switch to 5V.
Disconnect the Alcohol sensor from the base shield when uploading code to the Arduino.

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Arduino to Grove 16x2 LCD module

The Grove 16x2 LCD module can operate off 5V or 3.3V.
I used 5V from the Arduino UNO.

Project Explained

When the Arduino is powered up, you will be presented with a message, "Alcohol Project by ArduinoBasics". This is a splash screen to introduce the project.
 
The heater pin on the Alcohol sensor is then activated, which can cause the program to hang. If you do not see the message "Heater Activated", and only see a blank LCD screen - reset the Arduino board. There is a reset pin on the Base shield next to the LED. This message will only display for about 3 seconds before it starts to take readings from the Alcohol sensor.
 
I am guessing that each sensor is different, however, I found that the sensor worked best, once it had been in use for over 48 hours. I normally wait for the sensor reading to get above 5 or 6 before exposing it to alcohol fumes. You will notice the readings slowly increase over time. Wait until the readings stabalise, which can take anywhere between 15-20 minutes, or longer if the sensor has not been used for a while.
 

 
In the presence of alcohol fumes/vapour, the sensor readings will drop, and will trigger the Arduino to change the display to show the rough concentration of alcohol in the Air. Do not expose the sensor to strong concentrations of alcohol for extended periods, as this may permanently affect the sensor performance thereafter. I cannot tell you what readings are NORMAL, because I only have one sensor, and have nothing to compare it to. I have seen my sensor reading get to 11.96, but have noticed that the maximum reading changes each time I test it (sometimes higher, sometimes lower). I am guessing that the surrounding environmental conditions will affect this maximum (i.e. temperature / humidity / air quality), and also the length of time the sensor has had to "burn in" for.
 
Once you reach the maximum value (or as long as you are willing to wait), go ahead and test it out. Hover the sensor over the suspiciously alcoholic festive punch, and catch out your sneaky grandmother.

Conclusion

The biggest learning points for me about using the Grove Alcohol sensor, was how surprisingly long it took for the sensor to stabalise, and I guess how impatient I am. These types of sensors are often advertised as being a way to create your own breathalyser. But I quickly found out just how hard that was, and after my experience with the sensor, I would never contemplate using it for that purpose, because I cannot verify the accuracy of the results.
 
Can it detect alcohol in the air? Yes it can. The Grove Alcohol sensor can give a rough estimate of the concentration of alcohol vapour in the air, and at best, I would say that it gives you a semi-quantitative result. The same sensor will detect butane, LPG, petrol, isopropanol fumes - which is good or bad, depending on what you plan to use it for.
 

 
One of the most common ways of reading the Alcohol results is through the Serial monitor. However, the Alcohol sensor would for some reason lock up or freeze the Serial communication. I found the best way to observe readings from the Alcohol sensor was to use a Grove LCD module.
 
The Grove LCD module was very easy to use and enabled a more portable project. Grove modules are generally very easy to connect to the Grove Base shield, and are very much "plug and play". The Universal 4pin cables, reduce the "rats-nest" of wires - endemic to Arduino projects.
 
I hope this tutorial has helped you somewhat. If you use this project, please let me know your experience with it in the comments below, and even better, tell me who you caught out.

 

 

If you found this tutorial helpful, please consider supporting me by buying me a virtual coffee.

 
 

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Description

This is a very simple project that turns a Rainbow Cube Kit from Seeedstudio, into a digital rain cloud. It features a relaxing rain animation which is ruined by a not-so-relaxing yet somewhat realistic lightning effect. The animation has a very random pattern, and is quite satisfying to watch. The strategically placed cotton wool on the top of the cube makes all the difference to the project, and is sure to impress all of your friends. Luckily, I have done all of the hard work for you. You will find the full source code for the animation sequence below. You just have to provide the Rainbow Cube Kit and the cotton wool. Have fun !!

Description

This tutorial will show you how to setup a simple webserver on your ESP-13 WiFi Shield and display a table of all of the WiFi Access Points within it's range (and refreshed every 5 seconds).
The ESP-13 shield will create it's own WiFi access point, which means that you can take this project anywhere you want to. You do not have to be connected to your home/work WiFi network to see the webpage. The limitation however, is that your device must be within WiFi range of the ESP-13 WiFi shield in order to see the results of the WiFi scan.

Let me show you how to put this project together:
COMING SOON....

Description

This tutorial will help you get started with the KEYES ESP-13 WiFi Shield.

The ESP-13 WiFi Shield is compatible with an Arduino UNO and has the same form-factor. Essentially this shield will give your Arduino project WiFi capabilities. While it interfaces nicely with the Arduino, it can operate without it. However, if I were planning on using the shield independantly, then I probably would opt for an ESP module rather than a shield.

I bought my shield from Jaycar (CAT.NO: XC4614), however you can get it much cheaper from other online retailers at about a quarter of the price. The instructions on the Jaycar website are not that good, and at first I thought I had bought myself a useless product. It just didn't seem to work regardless of what I tried. There were some tutorials online that gave me hope, only to find that my shield was not quite the same and therefore I did not get the same results. But after countless hours of trial and error and patching various bits of knowledge together, I finally worked out how to use this shield. Everything has fallen into place. And it is easier that you would think... let me show you how.

Parts Required

1. Arduino UNO (or compatible board)
2. KEYES ESP-13 WiFi Shield - from Jaycar (Cat. No: XC4614)
3. USB cable - to connect Arduino to Computer
4. 4 wires: 4 x Male to Male connectors

Libraries and IDE

Arduino IDE

While there are many Arduino IDE alternatives out there, I would recommend that you use the official Arduino IDE for this project. I used the official Arduino IDE app (v1.8.5) for Windows 10.
Make sure to get the most up-to-date version for your operating system here.

Upload BareMinimum Sketch

Upload a BareMinimum Sketch to the Arduino UNO (or compatible board) before making any connections to the ESP-13. We want to upload the BareMinimum sketch because we don't want the Arduino UNO interfering with our setup in anyway. Here is how to do that:

1. Start your Arduino IDE
2. Connect the Arduino UNO to the Computer using a USB cable
3. Select: File > New (or Ctrl + N)
4. Select: File > Examples > 01.Basics > BareMinimum
5. Select: Tools > Board > Arduino/Genuino UNO
6. Select: Tools > Port > COM4 (Your Arduino may be on a different COM port)
7. Select: Sketch > Upload (or Ctrl + U) - or click on right arrow symbol
8. After the sketch has uploded. Disconnect the USB cable from the computer/Arduino.

IDE Configuration for ESP-13

Now for the fun part. The ESP-13 WiFi Shield is itself a microcontroller, however, the Arduino IDE is not by default, configured to communicate with or program the ESP-13 WiFi Shield. We are about to change that:

1. Select File > Preferences from the Arduino IDE menu (or Ctrl+Comma)
2. Insert the following text into the Additional Boards Manager URLs field:
   If there is a URL in that space already, then insert a comma, and append the URL to the end:

   http://arduino.esp8266.com/stable/package_esp8266com_index.json

   
   
3. Once the URL is added, press OK.
   This will allow us to install the ESP8266 package in the next step.

Installing the ESP8266 board

1. Select: Tools > Board: "xxxx" > Boards Manager
2. Search for ESP8266 using the Search bar
3. Select the "esp8266 by ESP8266 Community" board from the list.
4. Select the latest or most up-to-date version from the drop-down box (eg. 2.4.2)
5. Press the Install button.
6. Make sure that the esp8266 board is installed. Then press the "Close" button
7. Choose the ESPDuino(ESP-13 Module) from the ESP8266 Modules list:
   Tools > Board: "xxxx" > ESPDuino(ESP-13 Module)

ESP-13 Flash Settings

You will then want to check that you have the following settings in the Tools menu of the Arduino IDE:

• Board: "ESPDuino (ESP-13 Module)"
• Flash Size: "4M (1M SPIFFS)"
• Debug port: "Disabled"
• Debug Level: "None"
• IwIP Variant: "v2 Lower Memory"
• Reset Method: "ESPduino-V2"
• VTables: "Flash"
• CPU Frequency: "80MHz"
• Upload Speed: "115200"
• Erase Flash: Only Sketch
• Port: - (we will select that later)

The Arduino IDE is now able to communicate with, and program the ESP-13 WiFi shield.
Now let us have a look at how to use the default AI-Thinker AT-firmware that comes pre-loaded on the shield.

Preparing the WiFi Shield for Communication

The Keyes ESP-13 WiFi shield comes pre-loaded with AI-Thinker firmware. I thought I just had to place the WiFi shield on top of the Arduino UNO, and I should be able to send through some AT commands via the Serial monitor. Yes - it is a shield, and yes, we will use it as a shield later on, but if you want to use the Serial monitor while the shield is sitting on-top of the Arduino UNO, you will need to make use of the SoftwareSerial library. You can go down this path, but it is cumbersome. There is a better way. We will still need the Arduino UNO, but we need to connect it to the ESP-13 Shield in the following manner:

Wire Connections

1. Make sure that the Arduino UNO is OFF (i.e. not connected to power or USB port)
2. Place the ESP-13 WiFi shield NEXT TO the Arduino UNO
3. Connect a Red wire between 5V on Arduino UNO, and 5V (Arduino side) of the ESP-13 shield
4. Connect a Black wire between GND on Arduino, and G (Arduino side) of the ESP-13 shield
5. Connect a Green wire between D0(RX) on Arduino, and TX (UART - Arduino side) of ESP-13
6. Connect a Yellow wire between D1(TX) on Arduino, and RX (UART - Arduino side) of ESP-13
7. Make sure that both of the switches on the ESP-13 WiFi Shield are in the "ON" position.

Serial Monitor Setup

1. Plug the USB cable into the computer, and the other end into the Arduino
2. You should see a Red LED ignite on the ESP-13 Shield.
3. In your Arduino IDE, make sure the correct COM port is selected:
   Tools > Port > COM4 (Arduino/Genuino UNO) - your port may be different.
4. The IDE recognises that an Arduino is using that COM port, even though ESP-13 Board selected
5. Open the Serial Monitor: Tools > Serial Monitor (or Ctrl + Shift + M)
6. Select: Both NL & CR from the drop-down box at the bottom right side of the Serial Monitor.
7. Select: 115200 baud from the other drop-down box in the Serial Monitor window.
8. Press the RESET (RST) button on the bottom left of the ESP-13 WiFi Shield.
9. You may see some garbled information come through, but you should see "Ai-Thinker Technology Co.,Ltd" and "ready" messages in the debug window.
10. You can now send through your AT-commands to the ESP-13 WiFi shield.

Using default AI-Thinker AT-firmware

Now is a good time to test the AI-Thinker AT-firmware. It is possible to program the Arduino to send a sequence of AT commands to the ESP-13 WiFi Shield, but for demonstration purposes, I will show you how to send the commands manually via the Serial monitor.

1. If you see "ready" within the Serial Monitor window, the ESP-13 is ready to receive AT commands.
2. Type: AT into the box at the top and press the Send button (or Enter)
3. You should now see the AT command in the debug window, and a response "OK"

If you received the OK message, then your communication with the ESP-13 was successful.
A good list of AT commands and explanations can be found here.
Another list of AT commands can be found here.

The commands allow you to test, query and configure the ESP-13 shield. Essentially a command-line interface. Try out the following commands to get a feel for these functions/queries. The commands are in bold, and I placed some of the responses that I got in the line below.

1. AT
   Response: OK


2. AT+RST
   This resets the ESP-13 board. It provides some info about the board.


3. AT+GMR
   AT version: 0.40.0.0 (Aug 8 2015)
   SDK version: 1.3.0
   Ai-Thinker Technology Co.,Ltd.
   Build:1.3.0.2 Sep 11 2015
   


4. AT+CIFSR
   +CIFSR:APIP, "192.168.4.1"


5. AT+CWMODE?
   +CWMODE:2 [1=STA, 2=AP, 3=BOTH]


6. AT+CWLAP
   ERROR


7. AT+CWMODE=3


8. AT+CWLAP
   +CWLAP:(3,"MYACCESSPOINT", -53, "xx:xx:xx:xx:xx:xx",6,-12)

So there you go. Now you have everything need to configure your ESP-13 WiFi shield. Once you are tired of playing around with AT commands, I will show you how to re-program and upload sketches to the ESP-13 WiFi Shield, and use it the way it was designed to be used (i.e. as a shield). To upload sketches to the Shield, you will need one extra wire. But I think that deserves to be another tutorial. Stay tuned.

Summary

In this tutorial, I showed you how to configure your Arduino IDE for the ESP-13 shield. I also explained how to wire the ESP-13 WiFi shield so that you can communicate with it using the Serial monitor. I hope this tutorial helped you in some way. If it did, please let me know in the comments below. I will be following up with another tutorial, which will show you how to upload sketches to the ESP-13 WiFi Shield, and free it from your computer.

Description