YaYa's first GBZ - Kite's SAIO - Big Battery - NO Glue - Custom 3D parts - DC Jack - minimum case mod

[neolith]

Thanks for the detailed updates! Your thread will sure come in handy once I get to the point of tinkering with the software myself!

[Kayumba]

Spinning the FAN


After struggling to make the fan working... I abandoned and asked for help to Kite... He told me that actually the fan stuff was disabled as he moved it to Pi3Ext board
I asked for a method to activate it, and as Kite is really handy and willing to help, there you are

What do you need ???Show

IMG_0770.JPG
Kite told me to add Q11 (PFET IRLML6402) and R32 (a resistor between 10k and 100kOhm, SMD0402).
I ordered them and once i have received my parcel, i opened it and just thought : oh my god, how am i going to solder this

Where do we solder thoseShow

IMG_0773.JPG
The circuitry shematics
IMG_0771.JPG
The same place on the board, please don't pay attention to my cheap soldering made to the cables
look the next spoiler's pictures, i've reworked the solders
IMG_0772.JPG
Blank test fitting

Solder job doneShow

IMG_0775.JPG

It's alive and spinning weeeeeeShow

IMG_0774.JPG

When you power on the device, until Kite's startup script is loaded, the fan is spinning.
Then once the script is loaded, if the Pi's temperature is below the programmed temperature, it stops, otherwise, it continues to spin

You can edit the saio-osd.py file to change the value.

Code: Select all

sudo nano /home/pi/Super-AIO/release/saio/saio-osd.py

Find those lines

Code: Select all

temperature_max = 60.0
temperature_threshold = 5.0
temperature_isover = False

and change to match your needs (i've putted 55/5) Leave the parameter isover alone

as always, CTRL o to write Out the file, CTRL x to eXit the file

Looking for this mini cooler.
Can you give me a link, please.

[YaYa]

You can take a look at this website, but i don’t know if they ship worldwide

https://www.digikey.fr/products/fr/fans ... entilateur

Otherwise, i had it from Kite while i bought the SAiO.

[theklarken]

This is so crazy! You people on this site are crazy! I want to make one of these things very much! I need to start my studying.
Would any of you recommend starting with a project like this, or do you have a better path I should take to make sure i know what I'm doing? I'm not worried about the time/money investment, but am more concerned with a deep understanding of the craft. Is this the right thread for asking those questions? I apologize if it's not.

My background:
Cons:
I don't know what I don't know
Very little soldering experience
No Pi experience
Little SBC/electronics tinkering experience
Pros:
Job with good Linux/development exposure
Experience with networking/computer science

[YaYa]

update 10/10/2017

intensive battery testings !!!


Ok, i made my first real battery test in a real play condition.
The battery lasted 7,5hours

BUT, because there is a BUT

I am not totally satisfied by the result because it’s too far from my calculations...
Actually, i tested the battery voltage after the first complete charge within the SAIO. OSD display was telling 4.10V under load (of course, the unite was powered on). After switch off, i took off the battery and tested it with super RC car intelligent multi-charger. I had 4.03V, which is really far from 4.2V.
The battery took 7h30 to empty under heavy almost continuous playing...
I then recharged it with SAIO and i ended up to the same result. When the green charging LED truned off, i switched ON the device and i had 4.1V on screen. The multi-charger told me 4.05V.
I then put back the battery on the GBZ and charged it (the green LED turned ON). When the Green LED turned OFF, i unplugged and re-plugged the cord and the Green LED wen’t ON once more.
Then i was unable to charge it more. I had 4.1V with my charger voltmeter.
I took a look to the saio-osd.py file and discovered that there is a scale factor for the battery.
I talked with Kite and he told me that this factor was there to adjust the reads between the software and the real state of the battery so i’m gonna play with it to fine tune it and thus, have a more accurate battery condition read

I know, i am a psycho-depressive of optimization

I hadn't time to test the 4.1V batery lasting, it should gives me something around 8h...

Then i’ll measure the battery state under load and accomodate the scale factor to have an exact display on screen and then, i will charge it to max and play to discharge it till zero.

The first run completely depleted the battery to 3.0V.
I was suprised not to have a countdown or a soft power off. Instead, it went to hard off because of lack of power

And to tell you everything, the SAIO really acts like a UPS... switching from battery to AC/DC cord is seamless
This is a really cool feature.

I’ll post updates about he battery fine tuning.

[YaYa]

This is so crazy! You people on this site are crazy! I want to make one of these things very much! I need to start my studying.
Would any of you recommend starting with a project like this, or do you have a better path I should take to make sure i know what I'm doing? I'm not worried about the time/money investment, but am more concerned with a deep understanding of the craft. Is this the right thread for asking those questions? I apologize if it's not.

My background:
Cons:
I don't know what I don't know
Very little soldering experience
No Pi experience
Little SBC/electronics tinkering experience
Pros:
Job with good Linux/development exposure
Experience with networking/computer science

Yes you can post any questions here and i will help you.
Yes you can definitely go with that build with your skills because Kite’s SAIO make hardware stuff really easy to go
And yes this is a cool site and people here are sooo cool
Even if i consider each of them, me among them, as a heavy geek

Thank you for the thumbs up

[theklarken]

Yes you can post any questions here and i will help you.
Yes you can definitely go with that build with your skills because Kite’s SAIO make hardware stuff really easy to go
And yes this is a cool site and people here are sooo cool
Even if i consider each of them, me among them, as a heavy geek

Thank you for the thumbs up

Awesome! Thank you very much, and I think everyone here is cool, too! I can't wait to try it, I'm going to order one when the pre-order is open, and, between my crazy work schedule, I hope to finish a first build sometime by January-February!

This documented experience/tutorial is very helpful, the thanks is deserved!

[kite]

RE: your estimates, you were measuring the current when using USB (5v) but when running for battery you are going to have less than that, therefore to produce the same power (WATTS) you need more current! So 5v@500mA = 2.5W (5v*0.5A), to get the same at 3.7V is 675mA (2.5W / 3.7v). As the voltage drops lower the current increases..

Now the battery is rated for a complete capacity (at a FIXED drain rate) however the use here is a VARIABLE drain rate (so calculations will never be 100% correct, because the higher the drain rate the 'less the capacity' and that really depends on your battery (for example, crap batteries vary WILDLY, quality batteries are more stable):

EDIT: Although at the drain rates we are using they aren't going to affect it too much, as the graphs below go into the AMPs territory which we're not even close to..

CRAP battery:


GOOD battery:


So with that in mind you probably want to take 2-5% off due to the variable drain, and also base your power readings from a 'typical' battery voltage, so somewhere between 3.5-3.7v .. OR measure it in WATTS or WATT HOURS because a "3.7v 4800mAh" battery is 3.7v*4Ah = 17.76W/hrs.. so at 500mA drain (5v*0.5 = 2.5W) that makes (17.76/2.5 = 7.1hrs) which is closer to your actual usage!

[YaYa]

Hey Kite, thanks for pointing those things out !

You are totally right, i forgot the loss of power from the 5V to 3,7V conversion

I was (wrongly) assuming that if i was reading a current drain in mAh, i would drain always the same current...

So my battery lasting estimations under 5V feeding, although hypothetical, were not bad, and the battery lasting i am having under typical 3,7V is not bad

However i was wondering how it’s possible that the BMS didn’t completely fulled the cell ? My RC charger is very accurate, i’m using it for RX/TX lipo batteries, also for glow starters which are NimH, for my lead gel battery for the starting block, and finally for my 8000mAh 2S LiPos for my onroad brushless car. I had never a wrong reading whatever control tool i’ve used.

Maybe the BMS chip you are using have a higher security treshold and thus, does not fill at 100% the battery ?

As you are here still helping me figure out things, what should occur normally when the battery is depleted ? I was really surprised having the device shutting down suddenly without a safe shutdown ! The scrren made some weird flickering for 1 seconds and then poooof. Black out. I didn’t see the shutdown message in the console.

Thank you for your help !

[kite]

No problem As for not charging 'fully' the voltage isn't everything and the BMS is all in chip (I don't have any control over it) however you will probably find it will charge better if the SAIO is OFF because if you USB cable powering thing thing isn't high enough current (or the USB port/wart isn't up to spec) then while the system is charging it may be draining from the batt at same time (internally, if the voltage drop at the charging input is great enough it will prevent the battery reaching full! One option is to put 5.5-6v into the charger (SAIO is SAFE to support up to 6v iN), better USB/cable, or charge with it off.. the other part of issue is that the chip implements it's own algorithm and based on time at 'low charge rate' it may decide to turn itself off, which if you plug it back in starts the timer at 0..

The GOOD news is that for my next evolution of the SAIO I have used a different IC that is WAY more intelligent You may be currently missing out on 200-300mAh of power currently, which is a small amount overall but that's just the quirks of how it ended up working.. so a lesson to me and to anyone dealing with batteries, it's not simple

I haven't implemented any warning/auto shutdown and it is on my TODO list.. the reason was because when testing and debugging i didn't want my systems powering themselves off! It is just a python function away! Typically if the bar is empty you SHOULD shutdown the one ISSUE with auto-shutdown is that if you don't SEE it doing it, then the system will remain powered on (as the main switch is still on) so it would continue to drain power.. i guess in reality this isn't really an issue .. maybe i just prefer powering the system off myself!