Though not fully finished, I am prototyping a new in-wall switch/scene controller with an integrated 128x64 OLED display. The design is made to fit my decora wall switch design that I had posted a while back. Here is a mock up of how I think the keypad and screen will be layed out.
!

For the screen, I am hoping to display the current room temperature and possibly the outside temp. I can also scroll messages across the screen if needed. I can also do some custom graphics and icons.

I have tested the display connected to my uno with the Adafruit sample code and think it does a nice job. This is not my video, but it is the same sample code that I used to test it.
128x64 cheap OLED display Adafruit library Arduino UNO – 00:59
— Cutter Slade

I'll post more as I get further along.

I thought I would post a few custom icons that I made for my Domoticz setup. If anyone is interested I will post the zip files needed to add them to Domoticz.
Garage door controller

Irrigation zone sprinkler

Motion detector

So my latest project has been to replace an X-10 FloodCam (VT38A) motion sensor light controller with a MySensorized controller. I had been having some problems with the light getting stuck on for very long periods of time. The other issue was that this, like a lot of my other X-10 modules, I couldn't get a status reading from it, which was annoying. It had a built in camera which was wireless, but you needed an X-10 receiver to use it, and where I had my equipment, the picture was crappy at best.

I had some relay modules that were given to me by a friend, so I thought I would use one on this node. The node has 3 parts, the motion sensor, an LDR sensor, and the relay module. The concept is simple. The LDR is used to detect dusk/dawn to only allow the motion to turn on the relay/light when it is dark outside. I had a project box that I bought a while back for another project that I never used, so I figured this was the perfect project for it, but the trick was making everything fit.

The relay module was a 12 volt module, so I needed a 12 volt supply. I opted for the HiLink HLK-PM12. On the 5 volt pro mini that I was using, the regulator would get quite hot with 12 volts on the RAW input, so I decided to use a second regulator (LM7808) to drop the RAW voltage from 12 to 8 volts. It meant that I was regulating the voltage twice, but it worked well.

I took the old mounting tube off of the old floodcam and used it on the new setup. That now lets me swivel and point the sensor box to wherever I need it. It also lets me run my 120 volt power wires into the light assembly. The power wires are:

• Black - Hot
• White - Neutral
• Blue - Switched hot for lights

One other thing that can't be seen in the pics is that I put hot glue over most of the screws and nuts that were coming out of the plastic case. I did this to help prevent them from getting wet and rusting. I did this at the last minute before I installed it which is why it can't be seen in the pics.

Here are some pics of the setup.

Still need to do some setup and sorting of things, but here are some pics of my newly remodeled workshop area.



I really need to get rid of that old Leader analog scope and get myself a DSO. It is a conversation piece though. I have it connected to my old heathkit square/sine wave audio function generator. Does anyone have a recommendation on a cheaper DSO that would be good for microcontroller work?

Finally finished my 2.2.0 gateway and have it mounted in the new enclosure. It appears to be talking to my 2.0.0 sensors just fine.!

Though not MySensors related, I thought I'd post my latest build that has been consuming a lot of my time lately. This is the main reason I haven't been on the forum much lately. I bought a drone kit recently. Here are some pics from the initial assembly:

Since the initial build I have flown it and from a hard landing broken one of the cheap plastic legs that it came with. I designed a replacement with my 3D printer and some 1/4 inch aluminum rod.

Here are some pics at it's current stage. I have designed and printed some prop guards and a few other add-ons:

I have also designed and built a small servo based 3 axis camera gimbal. The controller was built using one of my spare 5 volt pro minis and an MPU-6050 accelerometer. Still working on the parts that will attach it to the drone, and I still need to pick up an FPV camera to attach to it, but a simple FPV cam is cheap.

So after getting my 3D printer I was thinking of all the MySensors projects that I could build with it. One of the things that I had looked at previously was setting up a weather station for my setup. The problem was that I would have had to buy some commercial weather station hardware and try to convert it to work with MySensors. The hardware alone for these was a bit expensive, not to mention the work it would take to convert it.

Having a 3D printer now has opened new doors for this project. I started working on designs for the parts to this and have some good progress. I still need to work out some of the electronics, but that will come in time as I get parts built.

One of the first things was designing a tipping bucket rain gauge which I have some posts on in a topic under hardware in the forum. I still need to print some parts for this. Started printing some things and ran out of white filament. Just got my new roll in the other day, so I will most likely start these in the next couple days.

No weather station is complete without wind speed and wind direction sensors, so that's what I decided to embark on next. Since I had to wait for my new roll of filament, I decided to work on some of the design. Here is the proposed design that I came up with:

This design is loosely based off of some setups that I saw when doing some google image searches. I started with the anemometer cups. I found an OpenSCAD design for these on thingiverse http://www.thingiverse.com/thing:34644 and used that as my starting point. I designed all of the other parts around this. So the only part of this that I can say is not truly my design is that. There are 12 parts total that I printed for this:

• 3 anemometer cups with arms
• Central cylinder that the cups mount to
• Bottom case with square mounting peg that holds the anemometer sensor
• wind speed rotor that holds the magnet for the sensor
• Top case that holds the wind direction vane
• The wind direction cap
• 2 wind vane arms to hold the tail fin and the nose cone
• The tail fin
• The nose cone
  One last part that I have not designed yet which will be pretty simple is the internal wind direction rotor that will hold the magnet for the direction sensor.

Here are some pics of the finished parts:

Wind direction vane inside showing 1 inch roller bearing

Anemometer inside showing the mounted rotor.

The full assembly

For the screw posts to hold the cap and base together, I took some stainless circuit board mounting posts similar to the ones below that I had in my parts bin and use my soldering iron to melt them into the holes. My guess is that the melted plastic took a good hold of the threaded end, so I doubt they are coming out.

All in all, the project is coming together nicely. Once I get a few more pieces together, I will post all of this on my thingiverse page and give the link to the group. I will post further details on this as I get things done. I always welcome comments and suggestion to my designs, so if you have any, feel free to post them here.

First attempt playing with the logo. I did a manual filament change from yellow to blue. Didn't have any black PLA, only ABS, otherwise I would have used black. This is more of a lithophane style which didn't do the best, but is still okay. I want to try to figure this out using paths in inkscape and exporting them to OpenSCAD. Having some trouble with that though. I'll figure it out in time.

The picture is next to a soda can so you can get an idea of the size.

So I have uploaded the 3D design files for my MySensors gateway case to thingiverse for anyone that is interested.
https://www.thingiverse.com/thing:2904969
I have included the OpenSCAD file used to generate the .stl files. I would be interested in seeing posts of other makes or remixes of the design.

Thanks to the core team for a great platform and all the work that you have done, and Merry Christmas to all on the forum.

@alex_the_techy I have had an A8 for just over 2 1/2 years now and it has been a relatively good entry level printer. Most of these entry level printers have some quirks about them, but they give you a good start into 3D printing. It does have an acrylic frame which is not quite as sturdy or durable as the aluminum extrusion frame that something like the Ender 3's or the Creality printers have. You can pick up an Ender 3 now for less than $200 US at aliexpress which is right around the same price as an A8. I would go with that over an A8 if I were to buy one these days. Many people that buy the A8 printers end up doing an AM8 frame conversion on them which basically gives you a frame similar to the Ender 3. I am not sure what the cost of the AM8 extrusion parts cost, but whatever the price is, it's too much when you can start out with the Ender 3 for around the same price as buying an A8 and you don't have to go through the hassle of the conversion, which by the way requires some 3D printed parts.

Another thing that might be cool would be to figure out a way to do something with EL wire. If you are unfamiliar with EL wire, the EL is for ElectroLuminescent. You can get many different colors of EL wire and a controller from SparkFun. https://www.sparkfun.com/products/12781
And here is an example of something someone did with EL wire.
https://www.youtube.com/watch?v=1lGfMqEstKA

On the lines that @TheoL was talking, here is some information on doing DMX with Arduino. https://playground.arduino.cc/Learning/DMX/

@nca78 said in Best sensor for falling alert:

a LIS3DH will use 50-100 times less current for free fall detection (between 6 and 11µA), ADXL345 over 10 times less (40µA)

That is an excellent point. If using it for personal monitoring, quiescent current draw would definitely be a factor. The longer you can have the device last on a battery charge the better.

I had just used the MPU-6050 for building a recovery parachute system for my drone in which I needed free fall detection, and it worked well which is why I commented on that one.

@nca78 said in Best sensor for falling alert:

There are accelerometers with built-in free fall detection, you should use one of those.

The MPU-6050 has built in free fall detection using an interrupt.

@bjacobse I have done a little bit of work with the MPU-6050 IMU sensor (made a servo based 3 axis camera gimbal and a free-fall sensor for deploying a recovery parachute for my drone). I would think that with the MPU-6050 you should be able to distinguish between the two scenarios you mentioned. I can't say for sure, but if you looked at the data from the sensor in the two different scenarios I would think that you would be able to find some discernible difference and be able to code for that type of scenario. I think it would be worth doing some tests to see. The sensors are cheap.

@nagelc Just ordered one of those buck converters from Digikey. Thanks for the suggestion. That might fix my whole issue.

@mfalkvidd and others. I am aware of what buck converters are and have used them before, what I was trying to avoid was changing the design of the case to make more room for something like that, but I guess if it comes down to it I may have to. I was hoping that someone might have a solution that might fit my space constraints. I like the one that @nagelc suggested as it looks like it might fit in the space I have. Another option I thought of if I had to change the size of the case was to use a couple batteries. I have some extra 18650's in my parts bin, I would need to check the current draw to determine how long they would last powering the UNO and the TFT shield.

As for the relays, I am switching them from the original 5 volt coil ones to 12 volt coils. I have decided to power them from the 12 volt supply as I should have plenty of current from that to hold a relay or two since that comes from the house batteries of the motorhome. There would never be more than two relays energized at one time since one relay is for heating and one for cooling, So it would either be a heating or cooling relay and possibly the fan relay being powered at any given time. I like the suggestion @skywatch made about using latching relays to save power, the only problem in using those is that I am limited to 3 data lines (D0 - D2) because of the TFT shield. My understanding of latching relays is that there are two types. Single coil which uses reversing the polarity for set and reset, or the dual coil type which use one coil for set and the other for reset. I think in either case I would have to use more than one data line for each relay which won't work.

My main question with this was what is a small cheap and cool (literally) way of getting the 5V I need for the UNO from my 12 volt supply. Preferrably something other than a linear regulator.

So this project at this point in time is not a MySensors based project, but I may make it into one in the future and use one for my home. That said,

MY PROJECT

My project is a digital thermostat using an arduino uno and a 3.2 inch touch screen TFT shield. This thermostat is going to replace the thermostat in my RV.
One difference from an RV thermostat to a normal house thermostat is that the house system typically runs on 24 volts AC whereas the RV runs on 12 volts DC. My original plan was to use the incoming 12 volts to power the uno. The specs for the UNO say that you can put up to 12 volts in the barrel jack. The only problem I have with this is that the linear regulator that the UNO has gets quite hot when running it from 12 volts. This heat will no doubt affect the temp sensor that reads the open air temp. I need to find a reasonably small way to regulate 12 volts to 5 volts without a lot of heat.

MY DESIGN:

And now a bit about my design. I have most of this built and my firmware is nearly ready. I am designing it as an auto changover setup with a relay for fan speed (low or high). Here is the board setup that I have.

The area of the board marked in yellow will be where the screw terminals will go for connecting it to the system. The 3 relays are heat, cool and fan. I was originally going to use 5 volt relays supplied from the 5 volt pin on the arduino. I found out that when two relays would trigger, the UNO would reset. I tried adding a capacitor to the power line near the relays, but that didn't help. I am changing the relays to 12 volt relays so I can just use the incoming 12 volts to power them. I am triggering them with NPN transistors connected to 3 digital pins.

Here are a few more pics of the setup. I have designed and 3D printed a case for this also.

This is with the TFT shield in place.

And this is with the cover in place. The cover needs a little bit of cleanup work, but otherwise not too bad.

MY FIRMWARE

And now a look at the firmware. The first image is the main screen. The main screen shows the current temp with the HVAC, fan status and set point on the right side of the screen.

The main screen has two touch areas, the gear in the upper left corner and the set point box. Touching the gear icon gets you to the settings page, seen here.

When you touch to change any setting, it is stored in the EEPROM on the UNO allowing it to recover on the same settings if it were to loose power. Most of the settings are pretty self explanatory except for the threshold and changeover settings.

The threshold value is either added or subtracted from the set point to offset when the heater or AC is switched on to know if it should have the fan on high or low. if the temp is with the threshold value of the setpoint, the fan is set to low, otherwise set it to high. On the RV, this just sets the fan to low or high. On a house multi-stage HVAC system it could switch stages.

The changeover value tells the system how many degrees the temperature must go up or down from the setpoint before the system changes over from heating to cooling or vice versa.

Clicking Exit at the bottom will take you back to the main screen.

On the main screen, clicking anywhere in the box that shows the set point temp will take you to the setpoint screen.

This screen is self explanatory in its function. The up and down arrows let you set a new setpoint, and Exit at the bottom will take you back to the main screen. The setpoint value is also saved to EEPROM on any change in value.