@NeverDie Thx for appreciating the work done. There will also be an open source part in the future. When and how extensive the open source part will be, remains to be seen. The release of certain information (block diagram, ..., in this post) is related to those open source parts.
There are some OBD solutions, however most of them (in my experience) give back low frequency data put by the car manufacturer on the OBD-bus (CAN, ...). Therefore transients evolving directly from the battery could only be recorded if the manufacturer sends those data accordingly on the bus. Due to the small bandwidth(also because of other car data that have to be sent, ...), such battery data are sent more often once per second or less. Fast battery events (i.e. cranking events, ...) are therefore imperceptible. Unless the manufacturer processes the fast events and then sends them (once per second or less), which is very unlikely if the manufacturer does not market this feature itself. Third parties devices for high frequency sensing costs several hundreds dollars.
In my experience, important battery states (especially the fast ones) are recorded by measuring and processing corresponding data directly on the battery.
I agree with you about the limits related to the communication over Bluetooth. But i think Bluetooth 5.0 will improve a lot. However, WiFi will always remain an important option due to the high data throughput. The combination of both (BLE & WiFi), especially with regard to energy consumption, will gain in importance.
Thanks for the answers. For sure it is possible to buy an ATmega and even a full-featured debugger would be acceptable compared to the effort of porting. But still, I am very biased towards the PIC without logical or economical arguments.
I did not yet work with the mysensors libraries and only browsed quickly through the github repo. Maybe someone can give me a few hints to estimate the effort deeper than just claiming it as "much workload"?
What I see so far is:
make the C++ code compile (translate to C with clang/llvm and compile with the XC8 compiler)
create a new HAL (in hal/architecture) which seems not too much effort for making it initially working
Questions:
Do I see it right, that there is a linux-port available? -> I would expect much more effort to port from AVR to linux than to port it to a different MCU
What about the licensing? It looks like the code is GPLv2, but in the CLA it seem that contributors need to give away their rights on the contributions and that mysensors can even redistribute the code under another license - which seems completely against the principles of the GPL. Can someone explain that in more detail?
@Nca78 Yes, I was actually thinking using DIP switch (or even more easy to read thumbwheel switch) to give a unique ID to each node! As soon as I receive the extra radio modules I ordered, I'll test that.
@Grubstake I'm afraid you're right! But it's ok to have just a few days of battery life. As I wrote, it might be often disassembled and reassembled.
@victus Im not familiar with this components you mention, you need to test yourself, cant help you with the technical stuff.
It does not seem to be a fully functional ECG but a heart rate monitor. As epierre said above, you need to define if you want to monitor or have a fully functional ECG, its a big difference. With a monitor all you get is pretty much your heartrate and you can detect arytmias. A fully working ECG is normally made with 12 leads and is used to in detail know how the electrical depolarisation from different time and direction/place within the heart muscle works. Holter is a example of a heart rate monitor over time.
This is a simple, low-cost and quick project that can get a high spouse acceptance factor.
Mirror
Remove the led strip from the aluminum profiles.
Cut the aluminum profiles and the covers to appropriate length. I used a hacksaw to cut profile+cover at the same time to ensure the got the same length.
Cut the led strips at one of the cut points using a side cutter.
Remove the old wires (they are too short to reach the box) and solder new wires.
Put the led strip back inside the aluminum profile. Note that there is a small grove at the back for the strip, this ensures that the strip is close to the profile to maximize cooling.
Glue the profiles to the mirror. I used slow-curing epoxy.
Electronics box
Drill holes in the project box for the switch (6mm) and the potentiometer (6mm should be enough but was too tight so I used 8mm).
Drill a 4mm hole for the wires to the led strips.
Upload the sketch to the Arduino
Connect the Arduino and the battery packs and put them inside the project box.
Fasten the project box using double-sided tape.
Big thanks to my wife for letting me use the action photo.