The Robot Thread

I should have done my homework better on LiFePo4.

The batteries I got work fine but when I went looking at specs I noticed the deluxe LiPoFe4 from Powersonic have 3X the energy density.

I will not buy anymore motorcylcle batteries.... Only purpose built.

I can tell by tapping on the battery it is only half full of cells.... The top half is hollow. BMS is on very top.
 
I see USART in the pdf file for Nucleo. I need to look that up. Why are UARTS called that.
Click to expand...

USART is an enhanced variant of UART, capable of both synchronous and asynchronous communication, and in modern microcontrollers it often replaces the simpler UART
 
I wanted to do a wrap up of my work to convert a Mobility Wheelchair into an Rover.

Pic. 1
Backbone is 2S 4P so I can change batteries without going down. An isolator circuit in between the two packs 4P would be ideal.
This will power my Flight Controller and Accessories. It also acts as a main battery holdown. Old rig used nylon straps.

Pic. 2
24V Main Battery cutout switch with fusing. Very crude but works. Need to make a knob and pullcord for knife.

Pic. 3
RunCam Robin3 and DeeGoo-FPV GPS/Compass. Cracked it open and inside was M9N ublox.
 

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resora
Sorry to bug you so much but I need your trusted advice. I want to monitor power.
I know my F405Wings have PDB/BEC and Monitoring. I am trying to avoid soldering those leads until I figure out wiring and connectors.
I have bulkhead/panel mount XT60 connectors that I want to use eventually.

I have bought a cheap power monitor device for benchtop use. Not much good with Rover on mission.
So I am looking at ways to monitor power. I know PIXHAWK had no integral power monitoring and they use a pigtail.
I like this approach but they seem to be using ADC and I don't know if I like that. I thought I would find i2c interface.

You can see from my Pic2 above that I have a nice gap for a shunt. I could do something there.
Opinions? Off the shelf items? What is good external power monitoring outside of the PDB/BEC found on some Flight Controllers.
 
ArduPilot already directly supports INA226, INA228, INA238, INA231, and INA260. It also supports multiple battery monitors at the same time, and each one can be assigned its own I²C address. ArduPilot also supports the INA3221, which is a three-channel I²C power monitor. However, if you are dealing with high currents, it would be better to use an INA228 or INA238.
 
I am going to buy a few of these to test. Three addresses to use. I will drill addition holes for one of these in the gap of my power switch.

Ultra-Precise I2C Power Monitor, I2C-INA-BM – MATEKSYS

www.mateksys.com www.mateksys.com

I also want to use a cheapo INA219 to monitor low voltage from LiPo to Flight Controller.

With the Matek having pass through connectors, connecting the second i2c monitor should be easy and minimal extra wiring.
Exactly why I wanted i2c. Daiseychaining.
 
I don't see MAUCH anywhere on ebay.
For Generic i2c modules for low voltage on Flight Controller I got some generic ones due to your input about ina226 chip:
5 pack of sensors for 21 bucks.
No jumpers/pads so they will go end of that daiseychain.

Anybody have recommendations on 'Temporary Jumper" to change i2c address on boards?
Also related: Nucleo Boards have a bunch of solder pad options that can be changed.
Bubble gum and silverdust?
JB Weld with tiny wire?
When I was afraid of using soldering iron on micro leads I tried some silver conductive glue. It was a mess and killed it. Should have made a mask.

Soldering Address is sorta permanent. I would like to test because end unit may not be selactable address.

Very small pitch:
 

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I have a very welcome Amazon delivery. Two ESC 70A Burst to 200A. USB Jack for tuning to suit motors with an application..
Flysky FESC6.7
 

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Phishfry said:
Need to make a knob and pullcord for knife.
Click to expand...
The nice thing about posting my pictures here is that I get ideas.
Instead of pullcord for power cutoff knife I will mount a handle that faces left. Away from circuit. Rotate left to de-energize.
Brilliant idea. I have no good mounting option for a external pullcord anyway. The machines Covers are only velcro hold-down anyway. Tearaway.
 
Soldering Address is sorta permanent. I would like to test because end unit may not be selactable address.

Very small pitch:
Click to expand...
you have a "zero resistance" tweezers, you can use it as a jumper for the test
You can wind the wires for the test and attach them with non-conductive tape to the pads
Also use pogo pins
 
I am firing up my rover project.. All parts are installed and doing fit&finish. Blocks under it to get it off the ground.
Tested motors with straight 24VDC Lead Acid Main Battery and that was a go.
Running CoreSolo F405-Wing from 18650 battery pack.
Soldering went OK for first one. Will get better at it. Learned alot.

Need to plumb GPS wires, Camera Wires and i2c for ina226 module & Matek i2c BM..
INA226 module is inline right now for flight controller and monitor 18650 use..
Just need to get i2c expander placed somewhere.

Adding an external port to my rover for my USB connection for the flight controller.
The 20 foot umbilical cord is functioning with MissionPlanner on laptop using FreeBSD.

I was worried that my ESC are bad. I tied the main batteries to the ESC with no RC-Line attached.
Red light came on and 2 seconds later went out.
Worried I yank the plug.
Thinking maybe issue with Lead Acid I gave LifePo4 batteries a shot on the other ESC controller..
Same thing. Solid Red LED for a few seconds then it goes out.
I hit the ArduPilot manual and see that I may need to calibrate ESC.
Before that I need to setup mode for Servos. I don't see SKID STEER. There is Ground Steer.
I think I have cleared the hardware hurdle. Now on to setup of my ArduRover.

Thanks resora for all the help.

I might add a RockPi4 later for additional control onboard. Atheros WirelessAP and more GPIO. Maybe I will use that as my ELRS.
I have UART1 set to RC_IN and I hope that my DSM Spektrum gear works with that.
 
I can't help but to notice that HUD is showing Bat1 without a working INA226.
So that was a waste purchase.
Very nice HUD feature showing 15.04v 0.8 A 26% from flight controller onboard PDB.
My batteries started off at 16V with multimeter. Been running 3-4 hours.
Nice how it is estimating runtime.
0.8A seems too high of usage. Might need to verify those numbers.
usbconfig was showing 100mA with no batteries in use.

I want to do a 24hour burn to see duration of flight controller 18650 battery pack.
4 cells x 4.1v full charge and should cut out around 3V or 12V for the four.
16V max to 12V cutout is my anticipated range.
 
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