[FC] - MultiFlite PICO-B-FC: Cleanflight F3 Quad FC

fc
multiflite
quad
pico
brushed

#1

Hi guys, I’ve been quiet for a little while and this is what I have been working on!

http://store.multiflite.co.uk/index.php?route=product/product&path=59_60&product_id=71

Key points are:

  • Cheaper
  • F3 CPU
  • Smaller (23x25mm) at 2.25 grams
  • Quad >8A output
  • 5V boost regulator on board (powers a TX5813 (25mw) fine + camera without filtering required!)
  • Buzzer support (transistor etc on board, just add buzzer)
  • Spektrum bind button
  • Single side populated, comes with mounting holes that can snap off
  • Right angled connectors, very slim mounting requirements
  • Giant battery pads, easier to solder (soldering required to get maximum current into FC)
  • 4 Layer PCB with dedicated planes for power and ground (maximum current)
  • Adapter to turn PICO FC into a HEX! http://store.multiflite.co.uk/index.php?route=product/product&path=59&product_id=73

One important thing you may notice compared the the NANO-B is that the RX connector is now 4x pins… the 4th pin is actually connected to “TX2” so any telemetry based receivers can use this pin (hardware inversion supported in cleanflight GUI). It is also there to make way for a micro telemetry based receiver from multiflite… but nothing to announce just yet :wink:

Any questions let me know :slight_smile:


Micro 32bits F3 Brushed FC
V1 scisky , dark editions, 200mw vtx/camera
Show us your builds!
Scisky nightmare
#2

Very nice work @giles!

Some questions (which I just answered myself by reading the manual - https://dl.dropboxusercontent.com/u/2831810/MultiFlite/PICO/MF_PICO-B-FC_V1.0_160720.pdf ):

  • TX1/RX1 TX2/RX2 TX3/RX3 accessible? Seems so! M1P, M2P, M3P, M4P pads are also a nice unique touch. Just in case you want to abuse it as a brushless FC.

  • Proper (compatible) betaflight target available? Seems SPRacing F3.

  • Is TX1/RX1 occuipied when using an FTDI? This seems to be a little different than on the SPRacing F3 - I think that uses the virtual COM port when connected to USB.

Nice FC. Just from the looks of it the best brushed (F3) FC on the market - congratulations! And the price is also reasonable. This thing is pretty feature complete.

EDIT: Ohh and let me honestly state the obvious: This just looks way more flexible and useful than a SciSky or the AlienFlight F3 boards - at least for a quad FC. You should be able to flash the latest Betaflight onto it and also - just in case you are crazy enough - have almost all options you would have on a larger flight controller. This makes this FC seriously outstanding compared to basically all other brushless boards (to the best of my knowledge). Everything is just right there - ready to be used.

EDIT2: Removed some stuff, this board obviously has no USB - which isn’t really much of an issue.

@giles: It’s very nice to see those break-off things and the right angled connectors. This enables a lot of very nice mounting options (just use rubber bands on those holes, screw it in. etc.).


#3

speechless. :clap:

Off to beg for more quad money.


#4

Some further questions I couldn’t directly find the answers to:
Hole dimensions? M2/M3? Hole to hole distances?


#5

Yep all available

Correct, I’m in the process of pushing changes that make it a new board define, as a variant of the SPRACINGF3. In the meantime the SPRACINGF3 + the instruction manual settings will get you there :slight_smile:

TX1/RX1 is available as the 4pin connector on the side (same as the NANO-B). This can be used for serial, osd, bluetooth, anything… the SPRACINGF3 doesn’t using Virtual COM, it has the CP2102 chip on it (so just uses normal serial)

16x30mm distance, the hole is M2. They are there to make testing and manufacture easier, they break off fairly easily and cleanly and would work well for mounting, they probably could do with being a bit stronger so I’ll address that in the next batch!

Glad you like to look! Really trying to push boundaries and improve upon previous versions! :slight_smile: Thanks for posting the link to the manual, as that does answer quite a lot of questions! :stuck_out_tongue:


#6

Ahh okay, didn’t know that - I have a SPRacingF3 Mini board which uses virtual COM and leaves the 3 UARTs free. So the non-mini SPRacingF3 FC is different - didn’t know that.

M2 holes - nice! Maybe some optional reinforcement options could be helpful - in case one uses any of the pads on the bottom, mounting the FC on M2 nylon hex spacers sounds like a nice option to me.

Keep up the good work!


#7

Looks very exciting! Does this board the same dimensions as the AlienWii and its cousins?


#8

It’s smaller:

Precise weight info would also be nice - is it really 3g or more like 2.5g, or heavier than 3g? :slight_smile:


#9

It looks like a good flight controller but it is quite a bit more expensive than this F3 priced at 19$ last I checked.

http://www.aliexpress.com/item/SP-RACING-F3-EVO-Brush-brush-flight-control-through-indoor-Coreless/32698592096.html?spm=2114.30010308.3.1.Trx7bm&ws_ab_test=searchweb201556_8,searchweb201602_5_10057_10056_10055_10049_10017_405_404_10059_407_10058_10040_10060,searchweb201603_8&btsid=2bf6e853-17e4-4d20-b05b-49a7fd863db0


#10

2.25g, I’ll update descriptions shortly

Yeah, you can tell when I designed it as the Mini and EVO weren’t out! Micro USB is useful, however when in flight it is completely wasted space/weight as nothing plugs in to USB… by using a TX/RX UART, you can plug an OSD/Bluetooth into this port which makes way more sense :slight_smile: But you already know this as we have talked about it in the past :wink:

True, I cannot compete on price but I can on quality (the price is cheaper than my previous HEX FC so that’s a start!). For example I buy the MPU6050’s direct from InvenSense (not cheap) because these are significantly better than the ‘cheap clones’ that Chinese based FCs use, any ‘drift’ or ‘after a hard turn it banks’ type problems are due to poor quality accs/gyros… seeing as this was the main part of an FC I make sure quality of this component is the best it can be!

I personally believe this FC to be fantastic and to be the AlienWii/AlienFlight replacement for the supply chain that hasn’t happened yet… while there are F4 based FCs teased, for micros the F3 is perfect and with a current loop time of 1000 on stock cleanflight, the PICO-B is no slouch!

Price is definitely a factor when choosing an FC, and what I am trying to do is bring high quality and high performance to enable a ‘race ready’ FC… for example the limiting factor on performance is now the battery cables and the batteries themselves, the FC can deal with all the current thrown at it!

There is a phrase something along the lines of “buy cheap buy twice”, but with my FCs you only need to buy once and you have a lifetime of support and quality. I hope it has been seen from my public interactions that I stand by my products and those who have emailed me should know how willing I am to support and help every customer :slight_smile:

Anyway enough rambling, reviewers of this FC have been nothing but positive, I hope some people take the plunge and see what all the fuss is about :slight_smile: If you’re not happy with anything just email me and we can sort it out.


#11

@giles I think that its top notch. and the price is fair. I have no doubt your support is too. Congrat’s on a nifty product.


#12

One more question which might be interesting for a few others here too:

  • From the looks of it you can have 5V power on the 4pin satellite port, since this is an F3 FC - SBUS should be possible (even with inversion and all that) on that port, right? So just in case one wants to - you should be able to use e.g. an FrSky XSR with this FC (assuming you have an appropriate cable for that - but that’s not much of an issue if you have crimping tools around already). Is this correct?

If all this is the case, this thing is just crazy versatile. Only minus for some people might be the “lack” of an USB port - which in my world is more a feature - especially when it comes to weight savings on tiny tiny brushed machines.
Doesn’t really matter whether I have to attach an USB cable or an FTDI adapter.


#14

Yep 100%, I don’t have a compatible receiver to try, but anything that is possible on the SPRACINGF3 (mini, evo, etc) is compatible with this FC! The XSR has the same pitch connector as the PICO (1.25mm) but in a 5pin version, I plan to buy one and make a cable and have it for sale (easy to make with crimpers/solder anyway) and document what pin goes where and what settings to use (should be self explanatory anyway). Do you have this RX? You could use S.BUS or S.PORT or PPM, all three are supported on FC!


#15

I have a couple of XSRs lying around - upgraded to FrSky Taranis some weeks ago. I also have the 4-pin, 5-pin 1.25mm pitch crimping stuff available. But I spent already quite some money on FCs lately… cough Maybe a little bit too much…


#16

Cool! S.BUS + S.PORT is what I made the 4pin connector for… RX3 is for S.BUS, and TX2 (UART2) is set to S.PORT. This way you get full telemetry and digital channel data from the 4pin RX port… if you wanted to use UART3 for something like OSD (to be honest you should probably use the UART1 where USB goes for this) you can set it to PPM and use that instead :slight_smile: I thought through these scenarios! The solder jumpers on the bottom are easy to change and don’t break off like the NANO did sometimes…


#17

Okay, now that’s thought through - so you are saying you can have RX3, TX2, 5V, GND on that single connector? That’s doing things right. I was already asking myself which of the TX pins goes to that 4 pin connector.

As a reference - the S.Port wiring on an full sized SPRacing F3 Mini is a complete mess.


#18

Yep that is the correct pinout, with RX3 also being able to be changed to PPM :slight_smile:


#19

Ok, I’m sold on this, looks great and promises loads. I was about to buy another Scisky but I’d rather give you my money for one of these beauties.
Hey being uk based means I don’t have the long wait I’ve come to expect with so much of my quad addiction :smiley:
I take they’re in stock and ready to ship?
Edit. I’ll find out, ordered already.


#20

Nice work on this @giles :slight_smile: I will be interested in getting one of these soon. Seems that you thoroughly noted all the things that can make this a great little FC including the thought of doing away with the USB for a UART connector to save weight and make the connector more usable for other hardware. The price on this FC is very reasonable knowing the quality is there and the main FC on the market that is a competitor is the Scisky which has some pretty crappy QC on those boards. The smaller size of this FC also will I am sure entice all of the Tiny Whoop or inductrix owners to look at this as a replacement FC for those stock RTF quads. Personally I will not even think about that until Blade gets a 8.5mm version of that RTF and all I would be interested in is the frame and props. I have a feeling this FC is going to be back ordered soon unless you have a really good stock of them.
About the cheaper alternatives and the Gyro or MPU6050. I have tried the cheaper ones in some of the AF FC that I have built and it has nearly drove me to insanity trying to figure out what was causing that DRIFT. The cheap knockoffs are for sure not worth the hassle and that is like you say one of the integral components of the FC. If that is not good nothing is. I have had builds that had drift as much as a degree every couple of seconds and in a hover you will see that. Others that were more like every 15 seconds or so that are not so noticeable but for sure effect the flight characteristics of the quad. Took me quite some time looking at these FC and trying to rework the MPU to come to the conclusion that it was not a fault in the build but the cheaper MPU that I purchased. I will not be buying any cheap ones again.
You do a good job at taking care of the clientele @giles and standing behind the product, that is success 101 and you’ve done a great job in that. I know if I purchase something from MultiFlite that I will not be talking to an echo because I have witnessed that first hand. Good product and great customer service is a hands down winner in all this. There may be a slightly cheaper product but as they say " you get what you pay for" cheap is not always equal to good.


#21

I have one :smiley:
It’s a beautifully crafted, tiny marvel, everything is so neatly fitted in and it looks feature packed!
I feel I need to build this into something special so I might take a while to decide just what. A collaboration with @woodsturning and @Benedikt and their fine products methinks. It’ll definitely be an fpv rig of some sort.
I do have an urge to just get it in the air to see what it can do though :smiling_imp: