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Suitable ESCs
#1
Given that folks on here have built their own PP Hardware setups, I have created this thread to share what ESCs people have used to save on a guessing game as to what simonk/atmega8 ones to buy?

Over to you all...
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#2
If you wish to build your own controller, to be clear, there are several options possible:

1) implement an hbridge using 4 mosfets. This is what I have done for higher current hydraulic motor controllers. This gives the best efficiency, but is the most complicated build.
2) use pwm style motor controller (not rc style) and make appropriate code changes. (edit: now code supports it via VNH2SP30 ifdef)
3) use brushed esc with rc pwm control, but beware, many reversing brushed esc limit reverse speed to 50%
4) use brushless esc reprogrammed to drive a brushed motor

for using rc style brushless esc based on atmega8 I have provided source code to work on simonk compatible brushless esc:
github.com/seandepagnier/brushed_tgy

afro_nfet.inc -- afro esc (no longer in production)
bs_nfet.inc -- blue series esc (no longer in production)
tp_nfet.inc -- tower pro and this covers most recent clones however I do not guarantee it

for recent simonk clones:

Probe the circuit board to determine which io pins it is using or there is potential that it will destroy the esc.

There may not be a working bootloader, requiring you to solder to the pads. Not all clones have accessible pads, in this case, solder to the legs of the atmega8.

Some clones use the internal rc oscillator, others use an external resonator. This needs to be set in the include file by F_CPU either 8mhz or 16mhz

Some clones have a working thermistor. If this is missing, there may be no temperature protection, however, you can position the thermistor on the arduino near the mosfets.
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#3
Just got this one working with a Nano -
https://www.ebay.co.uk/itm/30A-Mini-VNH2...SwUMxZlm4p

Using this sketch just to see it moving -
https://www.instructables.com/id/Tutoria...e-Single-/

And move it does! The old wheel pilot had been scrapped , seems to be loads of friction when engaged but the driver seems to work fine. 

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#4
i have one of those "VNH2SP30" let me know if you get it working on pypilot.Smile
mare liberum
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#5
I did order a VNH2SP30, but so far I have not received it. It may be a reasonable driver for tillerpilots and small wheel drives.
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#6
I'm just working out my setup. I use Sean's recommended setup Arduino Nano (Arduino UNO is not a 100% fit) in combination with a 15A ESC Brushed DC Motor Speed Controller by Hobby Components Ltd,  I use the default setup from PP (if not familiar with C, it's a bit complicated to change). I use it to drive a Vetus electric hydraulic pump, this is a brushed motor. In my lab i have it working. Next step is waiting for the Moitessier HAT for the Raspberry PI, which will be available end of October (regarding to Rooco). In the mean time i'm installing my hydraulic system in my boat (9 meter motor boat). I made some schemes etc, see my last contribution in the post regarding IO pins Raspberry (this is where i started, since then moved to additional Arduino).
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#7
I had success using unbranded Chinese ESC with a name like "SimonK 30A 2-4S".
The PCB is marked with:
SMK30A
2-4S

They work with tp_nfet.inc with a small change:
As there is no temperature sensing circuitry you have to set ".equ admux_temperature = 0" to avoid triggering the overtemperature fault all the time.
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#8
Some AtMega 8 based ESC's have Voltage, Current and Temperature sensing, as well as 2-way I2C communication onboard. Wouldn't it be a logical setup using all these sensors? Makes wiring everything a lot easier. Your probably aren't even in need of the Arduino anymore then?!
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#9
(03-17-2019, 11:21 AM)FMJ Wrote: Some AtMega 8 based ESC's have Voltage, Current and Temperature sensing, as well as 2-way I2C communication onboard. Wouldn't it be a logical setup using all these sensors? Makes wiring everything a lot easier. Your probably aren't even in need of the Arduino anymore then?!

In theory, yes,  but you still need a shunt to measure current.

The brushed code is written in assembly and only reads pwm input and drives the mosfets.  It also monitors current but that is it.  This isn't enough to make the motor controller which is why the additional arduino is needed.

The arduino nano code does much more, monitoring end stops, over current, as well as much more, see pypilot/arduino/motor/motor.ino    This sketch can drive mosfets directly without the esc, so you basically would need to run this sketch on the atmega8 of the esc.   Which it can barely fit in the 8k, but also might be lacking the needed timers, I didn't check much.   I think this may be where you run into problems but would be interested if you can make it work.
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#10
Regarding RC brushless ESC's. I have built over a dozen drones. I have found the ESC's to be the biggest point of failure. So just a warning that I would never built  something like PyPilot, that I must be dependent on to steer my boat, using an unknown or even cheap brushless esc. Sean if you like I would be happy to send you some good quality Hobbywing ESC's to play with.

Cheers
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