Homini Complete Room Sensor Module?

Samuel235

Homini Complete Room Sensor Module

General Description

I've been thinking about creating a module that will provide sensors for each given room in the house. My personal preference would use a nRF24L01+ to connect back to the gateway and also serve as repeaters for other modules to get back to the gateway. This would then enable you to essentially have repeaters in every room, but not just any repeaters, repeaters that would relay various sensor information back to the gateway saving your individual modules from needing to do so, allowing these smaller modules to potentially become lower power consumers.

Packaging

My thoughts at the moment would be to house all of the sensors inside of a 3d printed module case on the ceiling that would look somewhat like a conventional smoke detector mounted to the ceiling;

Possible specifications

So currently my list of possible parameters to detect would be:

Smoke
Gas
Temperature
Humidity
Motion
Light

Examples

Lets give an example where i would see this coming in very useful other than the generic smoke and temperature monitoring (and graphing).

Lets say that we would like to automate our curtains or blinds based upon the amount of light inside of the room currently, instead of creating the module for the curtains/blinds to include a light sensor and do the 'computing' of whether or not to close/open the curtains/blinds based upon the amount of light in the room currently, the controller would be able to send back a message when it needs the blinds closing or opening. This would enable a user to install only a slightly modified, if not standard, sketch for the blind module to work rather than having to redo the whole of the software side of the module to perform the task.
Another example would be to use the light sensor again to detect the level of light inside of a cinema room and adjust your ambient lighting automatically through the controller based on the scene desired (Maybe even have your controller do this automatically, thanks to the integration of systems such as Kodi/XBMC on certain controllers, Openhab support it from what i can see at least).

I'm creating this post before I go ahead with designing anything because I would like feedback from this community on what sensors would be more desirable to others based on your requirements. So, please comment and feedback to me with what you would love to see go into this module. Any feature suggestions are more than welcome, I look forward to developing this module.

scalz

@samuel235 : nice project. If you want some ideas...I am already making something like this
http://forum.mysensors.org/topic/2951/my-mysx-multisensors-board
but it's without smoke/gas sensor. Firstly because 328p has not so much memory so I don't know if I could fit smoke/gas in the code, maybe...And finally because I wanted a low power thing, not sure for gas.smoke sensors.
I thought too about using this kind of enclosure but I wanted something more generic I can fix to the wall and not always on ceiling so I choosed custom enclosure. And like this, it can be used for door reed switch too.
Not released yet, I know. I have mainly debugged it, I need to make some adjustments for my PIR lib and deeper tests for range etc...and in the mean time I have received some pcb and tools I need to be familiar with...so lot of homework!
For fine controlling rollershutter, we need ambiant light (I choosed opt3001 exactly for what you said it can interrupt and is ultra low power sensor but there are other chip), temperature, and uv sensor (ideal is a precise one, silabs one is not as precise as veml6070, I have made a board for this too). Sensors needs to be well oriented and uv ideal position would be glued on windows but not so sexy, so maybe I will put these uv sensors outdoor..Finally, ideally, have the controller telling sun elevation and azimuth (in jeedom controller we have a plugin for this).

I will look at what you will do :)

Samuel235

@scalz, nice work on that module!

Mine will be inside of a custom made case too, just that i wanted it to look like that photo that i included. I wouldn't attempt to put my device inside of one of those just out of simplicity to be honest with you.

The software/programming side of things is still my weak area, I will need to do some research on the amount of memory on-board the 328p and if its not able to hold the software i'll be looking at maybe another uC, not sure yet.

The OPT3001 seems to be better matched than my BH1750 chip i was looking at purely because of how closely it monitors the light compared to the human eye. Thank you for that suggestion, i will be sure to research this in more depth. In terms of your suggestions to sun elevation, azimuth and UV detection, do you feel that would be better suited to just one application such as a outdoor weather station rather than a device that is situated in each room indoors? I'm not well educated in these 3 sensors so maybe i don't know enough information to make a correct assumption, but they are my initial thoughts.

scalz

@samuel235 right, my uv sensors will be on a "weather" sensors board. Here my preview (right bottom corner shield with my 32bit atsam mainboard for more memory with lora or nrf. The top board one is my gesture/mems actuator).
http://forum.mysensors.org/uploads/files/1457300128047-2016-03-06_21-14-17.png
On my "weather" board, sensors will be optional because I will use one uv sensors per house side but don't need each time a bme280 or as3935 so...
I have received all these pcb and stencils this week..just need time!

Samuel235

@scalz, I'm sorry for causing confusion, I thought you were suggesting for me to install a UV sensor on each board, sorry :flushed:.

I really like the idea of your modular system with the daughter-board style approach. Will the main board work even if there is no daughter board is attached without modification to the code? If not that would be an awesome feature to attempt. Not sure how you would go about that, again my software side lets me down. I'm guessing you could have it all based on IF rules.

Looking forward to seeing your project come to life!

scalz

@samuel235 cool. yep mainboard is like an arduino (here an atsam=arduino zero) so it can work without daughter board. it depends what you need. mysxconnector is not my idea ;)

if you are curious (or perhaps @tbowmo lol) here a small pic of what I have received this week, not assembled yet..
http://www.hostingpics.net/viewer.php?id=43362320160320134635.jpg
On left my esp8266 adapter for nextion hmi screen (easy to solder 1206, optional lipo charger, onewire, si7021 and bh1750 emplacement...for a mqtt thermostat for instance, i am making sort of GUI). And on right a gorgeous panel with one stencil!! (multisensors with pir, my atsam lora/nrf mainboard, daughters boards (weather, gesture..), and adafruit m0 boards (why not!). Lot of tinker in perspective! It was cheaper to make everything on one board and cut myself than buying a multiple sub pcb + multiple stencil (for proto only).

Samuel235

@scalz, looks awesome! I too have a feeling that i will be ordering this module all on one board and maybe separating them up myself. Again, like you, it would work out a lot cheaper that way when there is a few different boards to make up one completed module.

Samuel235

Currently looking at air quality sensors, while the MQ2 is the most favored around here, it uses up to 800mW of power at 5v, which to me is pretty high when you have IC's like that of ccs801 which uses much much lower. I'm looking to have these directly on the PCB itself, so in this respect they do not need to be available on a pcb of their own like the MQ2 is.

Samuel235

Specifically looking at CCMOS and their range of air quality sensors. Due to them using waffer layer technology they have brought down the power consumption to <10mW compared to the standard Metal Oxide method of other sensors using >800mW.

Some data on their sensor that looks very appealing right now:

CCS801
Product Brief: http://www.ccmoss.com/sites/default/files/documents/CC-000083-DS-6-Product brief for CCS801.pdf
Data Sheet: https://www.terraelectronica.ru/show_pdf.php?pdf=/pdf/CCMOSS/MOX CCS801.pdf

They also do this chip with a built in ADC, however that is still not available yet, its still in sampling phases and not available for normal purchases. So i'll divert my attention to the analog version. I don't see any issues regarding it being analog, if anyone does please point them out to me.

Just some food for thought for tonight ;)

scalz

@Samuel235 nice sensors, I like sensors too..that make me thinking to try to make a small childboard lol I have no time.
I think @epierre is the air quality guru here :) curious to know what do you think..

But this little "nugget" certainly need some care like:

it is fragile (during assembly, esd, heat..), and it is dfn. so it's better to not fail during soldering because it is 7$!! and not sure it likes multiple solder/desolder.
its low power ability is possible only if you use pwm to heat it (or it will be a lot more). So it would require that mcu generate pwm during sleep! not possible in deep sleep ;) everything is powered off. The best bet (what I would do in this case if would do low power) would be to use timer2 in asynchronous mode to generate pwm and keep low power. or, if no pwm + deepsleep so no heater, I don't know how long time it really need to take a reliable value from mcu wakeup (need to be tested)
imho adc is not always as easy as it seems. curve (could need opamp maybe not here I don't know its curve), is it sensible to parasite, does it need filtering, etc..but that is electronic debug. That's cool when the chip has everything packaged with i2c and you just need to have a clean supply.
so follow only the ref schematic in datasheet may be not enough. but enough to play with, at debug you will see if you need to stabilize/improve adc or not

it's only imho, maybe I'm wrong or forgot details, but if it can help. btw cool idea :)

Samuel235

@scalz

I do plan on sourcing a hot air reflow station for DFN packages now, simply because of that pad on the bottom, otherwise i'de use a soldering iron for it. I'm pretty confident with soldering so this is the least of my issues if i'm honest.

Even though i'm looking to power this node via mains 240v, i'de love to get this whole node as low power as i possibly can. Initially i wasn't planning on sleep the MCU tbh, but i haven't evaluated the pins needed for the sensors yet, it might be a case that they will all be connected through interupt enabled pins, the new ATmega328pb may have more interupts, research needed. So if i could get them all on interupt enabled pins that would be fantastic news for power consumption to allow the MCU to sleep while monitoring is being performed still. It would be interesting to see if i could use some other IC to generate the pwm signal for this chip to be powered easily while MCU is sleeping, if i choose deepsleep that is. Normal sleep may be the only opinion anyway for me though.

I've ran into a few little issues in the past with ADC, namely the battery voltage monitor. So i think the fact it is analog is perfect for my application. However, i do think that it is all contained internally and just need clean power on that ADC version. But that isn't available anyway.

I'll now wait patiently for the master of air quality sensors to chime into this conversation ;) Then we have a few other little conversational discussions to have on here for the other sensors and the 240v powering situation.

Thanks for your input on that last post, i always enjoy our conversations and idea suggestions!

scalz

@Samuel235 : thx. good choice for hot air gun.
oki, I didn't know you want this node ac powered.
just a last thing..it's a big shortcut to think that analog signals is as easy as a simple resistor divider and read it with adc ;) imho analog is an art like rf. good filtering, opamp theory, mixed signals routing science etc.. I just say this because I'm actually learning and working on this at my job. I need to route a reliable board with lot of adc, digital, there will be can bus.., in harsh environment like car/trucks engine (hopefully for me I work with an analog guy, my dad, old school lol).
Don't worry, I think your board may not need all this care (I hope). it's just some points and so you can learn more. good luck :)

Samuel235

@scalz, it is a good thing i didn't think it was that simple and why i don't like using that method for the adc of voltage monitoring. From the other topic on here with the voltage monitoring you can see i was having a lot of issues with understanding the theory behind it. I don't like to do something because that is how it needs to be done, i'm the person that actually wants to underatand the reason and method of doing it and why.

Normally, old school is the best way to learn. The new methods are mostly better, but for the method the old school way is better. So thank your father!

I don't think these boards of mine will need the type of intricacies like you're having to do, but i'm always learning the methods and theories on why they need to be done like that.

scalz

cool, I think you will get this sensor working...even if now you don't need all these advice, maybe in future you will remember about it when needed ;)
humm, maybe at lunch I will try to make a basic and small childboard for this one..so I will be able to add it to my pir multisensors..very tempting, and so I would be able to help you..

Samuel235

@scalz Oh, no doubt about it i need this advice and i thank you for it. I definitely need it as i wouldn't be asking here ;)

From my findings i need a fair bit of help on the sensors them selves and their calibrations too.

A daughter board for which board? I'm intrigued to see what you come up with. I'm planning on having this split in two boards stacked on top of each other inside of the enclosure. One for power distribution and one for data and sensor connections.

sundberg84

:+1: Gas/Smoke/Temp/Hum/Light/Motion in one would be great!
For me its tempting when you are aiming at a celing mounter 3d case like a smoke detector.

I hope it can all be fitted inside a normal size case - you see, there are other aspects of it like esthetics according to my wife.

Samuel235

@sundberg84, i'm with your wife here. It must look appealing to the eye, hense why i wanted in a custom enclosure fashioned like that smoke detector/sprinkler image i included. Since its something being mounted on the ceiling, its got to be subtle and not in your face ugly.

I'm glad you're very interested in following this production, thank you 👍

scalz

@sundberg84 nice catch :)
@Samuel235 : this one (I showed you in post above) http://forum.mysensors.org/topic/2951/my-mysx-multisensors-board
On daughter board, the sensor would be on the left side of the pic because others sensors are on right (little dirty hack but like this I could have everything I need per room..depending of the sketch size too). I would add mosfet to cut power on daughterboard etc...a thing to try, I just need to make a tiny daughter board, oshpark and voila!

Samuel235

@scalz, ahh sorry i forgot you linked that. Yeah that would make that a nice little setup!

scalz

@Samuel235 : here what could look my small childboard...first pass, I will change few things before order it. 3.35$ for 3 boards at oshpark :) It could be smaller, it is because now I like/try to have everything ontop (but there are two smd jumpers on bottom), that made me hungry! time to eat :)
@tbowmo: here an idea for a childboard ;)

Homini Complete Room Sensor Module?