Hello! Anyway, here we are, you find a lot of materials in your hands, but, you do not know what to do with them, do not worry, in this manual we will try to guide you throughout the process! (Do not forget that you have the captor FAQ for any questions or queries that you may have, the link is in the references section.
Well, but exactly, what are we going to build? What is a Captor Node? its duties? Very briefly, since this manual does not intend to enter into aspects beyond the purely practical, a Captor Node is made to measure the level of contamination of the environment where it is placed, making use of sensors that measure both O3 and NO2. And save these values in the cloud so we can deal with them later.
Let's review before you start, do you have all the materials? (Check the sheet of materials in the annexes !!) All right? let's keep going!
The first thing we are going to assemble is going to be all the hardware of the node, we will take care of the software later on.
Well, we are going to mechanize the “housing” of the Captor, it is that white color box. You have to make 7 holes in a side, we use the following distribution, even if you can use your own!
Pay special attention to the diameter of the holes you make, since then the connectors of the sensors may not fit. (20mm diameter)
For now let's leave the box on its side, let's focus on making the sensor protectors, prepare the pipes and the heat-shrink tube, we'll need them!
The first thing you have to do is cut the PVC pipes (they can be made of any other material, even though this is the most common) You have to cut the 10mm inner diameter tube to a length of 10cm and the 20mm inner diameter tube to 6cm of length. Then we take the shorter thermoretractile tube and we use our personalized tool that in the part of the annexes we explain how to do. Do it as shown in the images below:
Well, we've done a lot of the work, but we're not finished yet, there's the wiring part left!
First we will solder to the shield all the pins that will be necessary to connect it to the arduino Yún.
Now that we have the male pins, we have to solder the female connectors where the majority of peripherals are connected, as well as the temperature and humidity sensor, or the O3 / NO2 sensors.
In the last photo, as you can see, I added some female connectors (the once that belong to T/H sensor)
Ok, we now proceed to solder the resistors that will make our sensors work remember the following:
For an NO2 sensor (MICS-2714) to work, it must have the following resistances: For the parallel: 1x220ohm & 1x330ohm For load resistance: 1x100Kohm
For an O3 sensor (MICS-2614, currently discontinued, we accept suggestions for similar devices with a similar precision / price ratio)
For the parallel: XXXXXXX For loading: 1x10Kohm
In the last two photos I added the LED female pins and its resistance (with 100 ohms we should go)
And the just solder it like that:
(PHOTO OF SOLDERED SENSOR)
Once the distribution of sensors you want and soldered the sensors, we just have to put everything together, as shown in the following scheme: (remember that before connecting a sensor, it must be installed in the tube that we have built before and this tube inserted in the housing)
(PHOTO OF THE FINAL CONNECTION WITH THE SHIELD)
Now we have to pass the USB power cable and ready, we will have finished Hardware!
To install all the software that is necessary to make the hardware run properly you need to do the following:
- Now its time to mount the filesystem on the SD card, to do so, go to the directory where the provided Captor software files are and run this command: “./format_sd_extroot.sh CaptorID_start CaptorID_end”. If you are only creating one node, CaptorID_start = CaptorID_end. - Before uploading our sketch to Arduino CPU, we must do several steps:
- Now we have to upload all the software that makes our Captor node work. Like in step 3, you just need to run the command like this: “./upload_software.sh CaptorID_start CaptorID_end 5”. The arguments work as the other script, just ignore that 5 as third argument, just write that :).
- Go to “network” → “Add New Interface”