• This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.

ZMR 250 Brain Fpv build

Ksu_fpv

Junior Member
#1
Parts
Brainfpv flight controller
Dys 1806 2300kv x4 motors
Dys 20 amp opto escs x4
Mini h quad zmr 250 pdb
Zmr 250 frame
TX5G6R video transmitter
Smc 600 camera
Taranis radio with X8R
QUANAM V2 goggles
RX5GR av receiver

I have my motors connected to my escs ad my escs connect to the power spots on the pdb.

The confusing part is the Brainfpv flight controller. I looked at their website when I first received the board but there hard ware schematic uses parts I am not going to use ie a lc filter, current sensor, external bec.

The part I am having difficulty with is where to connect everything to the brain I have a pretty good indication where the escs wires will plug in but as far as how to plu the x8r and camera and transmitter that's were I am having some difficulty. The brain came with wires for the board but they are open ended plugs.

Has any one set up a Brainfpv flight controller with a quad before, and could you give me some help?
 

cranialrectosis

Faster than a speeding faceplant!
Mentor
#5
I have a Sparky2. I kinda want a Brain (no input from the peanut gallery) and am intrigued.

The first thing I need to ask is, since you are using opto ESCs, how do you plan to power the Brain? From doc:
"Servo Port Main RC motor/servo output with 4 PWM outputs (up to 400Hz). It is recommended to power the Brain through this port (max. voltage 6V)."

A 2S lipo or higher directly connected to the Brain (other than the voltage monitors) will fry the board. You will need a voltage regulator or an external BEC to power the Brain.

You have a NICE receiver. I don't see support for Sbus (hopefully jason will chime in here) so do you plan to use PPM or PWM to get signal from your receiver to the Brain?

For the video connections I would need to google all the parts for voltage specs to see how they would be connected. Let's start with power and receiver.
 
Last edited:

Ksu_fpv

Junior Member
#6
I believe the Brain runs off of 5 volts since I cannot power it off of the escs I was going to power it off of my pdb. There is a 5 v connection to the left of the esc wires in the picture above. Also the pdb comes with a built in bec as well.

I am planning on using ppm for the signal. Also there is an onboard osd build into the Brain as well

The video transmitter is 5v output with 7-20v operating range

And the camera is 3.6 -5v with 5 volts being the max voltage.

Also I am running 1500maH 3s batteries
 

Ksu_fpv

Junior Member
#8
I have a build log showing how I hooked everything up to the Brain on my QAV400 if that helps.
I noticed you are using a current and voltage sensor. What are you using that for and connecting it to?
Also I'm planning on using ppm instead of Pwm for the x8r, is there much difference in connecting it up? C0d3M0nk3y
 

cranialrectosis

Faster than a speeding faceplant!
Mentor
#9
Sweet.


That's a NICE PDB. I should have paid closer attention. Very cool. It should make powering the Brain and camera simple. I had to ask. :)

To connect the receiver you will need a 3 wire cable with a female servo connector and a male 3 or 8 pin Brain micro connector. Connect signal 1, power and ground to the Brain receiver port pins for ground, v-batt and ppm.
http://brainfpv.com/support/hardware-setup/

Per the pic these should be the bottom three pins on the receiver port if the board is facing away from you and should be in order. If Brain gave you a cable with a 3 pin or 8 pin male micro on one side and a 3 pin servo on the other, that's your ticket. If not, you need to make one. It looks like they gave you lots of plugs with leads so you are good to go there.


Once the PDB has power you can use a 12v rail to power your video transmitter. You can use the 5v output on the video transmitter to power the camera. It looks to me like you will end up making your own cable here to provide 12v from the PDB into that vtx port AND connect to the camera with signal power and ground. The key will be keeping 12v away from your camera.

You may also power the camera directly via 5v if you have another open 5v rail on the PDB. I recommend you not permit the Brain and the camera to pull from the same 5v rail if you can help it. It shouldn't be a problem but if it is, debugging will be harder.


Jhitesma, hear anything about Brain and Sbus?? :)
 

Ksu_fpv

Junior Member
#11
Sweet.


That's a NICE PDB. I should have paid closer attention. Very cool. It should make powering the Brain and camera simple. I had to ask. :)

To connect the receiver you will need a 3 wire cable with a female servo connector and a male 3 or 8 pin Brain micro connector. Connect signal 1, power and ground to the Brain receiver port pins for ground, v-batt and ppm.
http://brainfpv.com/support/hardware-setup/

Per the pic these should be the bottom three pins on the receiver port if the board is facing away from you and should be in order. If Brain gave you a cable with a 3 pin or 8 pin male micro on one side and a 3 pin servo on the other, that's your ticket. If not, you need to make one. It looks like they gave you lots of plugs with leads so you are good to go there.


Once the PDB has power you can use a 12v rail to power your video transmitter. You can use the 5v output on the video transmitter to power the camera. It looks to me like you will end up making your own cable here to provide 12v from the PDB into that vtx port AND connect to the camera with signal power and ground. The key will be keeping 12v away from your camera.

You may also power the camera directly via 5v if you have another open 5v rail on the PDB. I recommend you not permit the Brain and the camera to pull from the same 5v rail if you can help it. It shouldn't be a problem but if it is, debugging will be harder.


Jhitesma, hear anything about Brain and Sbus?? :)
What about connecting to the av port on the Brain?
 

cranialrectosis

Faster than a speeding faceplant!
Mentor
#12
I forgot you also have an OSD...

Friggin' tax audits...

So the Brain has ground, video in, video out and audio out.

Run 5V and ground to your camera either from the PDB or the vtx.

Run 12v power and ground to your vtx from the PDB.

It is entirely possible that in that stack of micro connectors with leads you have exactly the cable you need with all the appropriate connectors to connect the Brain to all your video hardware. :)

Don't bet on it.

Use a 4 pin micro connector with a black wire on the left edge if you have one. Splice the black wire into the ground going to the camera.

The camera's video out wire is next. It is probably yellow. Solder that wire to the second wire in your 4 pin micro connector that plugs into the video in pin on the Brain.

You should now have power and ground to the cam from the PDB or vtx and video out from the cam and ground to the Brain.

The vtx gets 12v and ground from the PDB. It will have 5v power and ground output for your cam if you choose to use it and video in and audio as well.


Connect the video in on the vtx to the third wire in your 4 pin micro connector that plugs into the video out on the Brain. Audio goes to audio in similar fashion.

That should give you the goods.

These boards require making your own cables by splicing in the leads from the plugs that come with the board into other manufacturer's leads and plugs. It's half the 'fun'. :)

I find 1/16" or 3/32" black heatshrink (automotive at Ace Hardware), indispensable with these builds.

Keep us posted. I am thinking of a 4" Alien with one of these.
 
Last edited:

cranialrectosis

Faster than a speeding faceplant!
Mentor
#15
I think there are lots of reasons to want the gimmicks from a Brain. Mr Steele's in his epic 5" Alien build adds an OSD. In Formula 1 and NASCAR races, cars transmit telemetry for analysis.

Adding an OSD to a very small copter is challenging. The Brain seems to be a nice option.

I am playing with a Sparky2 these days. I am enjoying the setup with TAU. Hopefully I will get some flying time in after the holiday and I can try out things like Autotune. I also fly solo and often over chest high weeds. Telemetry may be able to save me some searching time when the wind is too loud for me to hear my lost model alarm after a crash.
 

C0d3M0nk3y

Posted a thousand or more times
#16
I noticed you are using a current and voltage sensor. What are you using that for and connecting it to?
I'm using it to monitor milliamps used. I have it connected to the Sen port (the middle one).

Also I'm planning on using ppm instead of Pwm for the x8r, is there much difference in connecting it up? C0d3M0nk3y
The X8R doesn't output PPM. It does output SBus if you want to use that. It should be simpler to hook up (1 wire instead of 8), but I don't know how to configure it in the software.
 

jhitesma

Some guy in the desert
Mentor
#17
I don't have any s.bus gear...but I have google :D

s.bus should be used on the "main" port on the Brain since that port has the inverter for it as per the Brain Hardware page:
https://brainfpv.com/support/hardware-setup/ In software you should just be able to select "s.bus" from the Configuration tab / Hardware page in the pulldown. I can't confirm because I don't have a GCS to match the firmware on my brain handy right now.

If you think wiring up OSD on the brain is hard you really don't want to try wiring up a standalone OSD!

You don't NEED a LC filter unless you're getting lines in your video. It's a good idea to have one, they're cheap and there's no real downside to one. But if you don't have interference in your video you can get by without one. So you can just ignore that.

Same with the current sensor, you don't NEED it, but it is nice to get the readout of ma used. Voltage is really nice to have since that's what lets you know when your battery is getting low :D You can't just wire battery power right to the SEN port though. You'd need to run it through a voltage divider to scale it to 0-3.3v or you'll blow up the Brain. You can get current/voltage sensors like this one:
http://www.rctimer.com/product-1096.html

Which will give you current AND voltage both scaled to 3.3v - just be careful, most of the current sensors out there only scale to 0-5v and would damage the brain (that's because the old 8bit APM boards used 0-5v and most sensors were designed for them, newer 32bit processors run at 3.3v not the 5v of older 8 bit processors so they use less power.)

Brain does include a cable to fit each port...but the ends are unterminated so you can do what you want with them.

Hope that helps fill in some of the gaps :D
 

jhitesma

Some guy in the desert
Mentor
#18
Setting up s.port telemetry back to the RX from the Brain is a bit trickier - you need to add an inverter circuit as explained on this page:
https://github.com/TauLabs/TauLabs/wiki/User-Guide:-FrSKY-S.PORT-telemetry

However I that back in Jan Shred was saying it's not currently enabled in Brain (http://www.rcgroups.com/forums/showpost.php?p=30388662&postcount=22) but he would do so. I looked at the release notes since then and don't see any mention of it so I'm not sure if it's enabled or not.
 

jhitesma

Some guy in the desert
Mentor
#20
One thing to add. The wire harness for the RX port connector. You can re-arrange the sockets on the ends if you want/need to to clean things up. Not the end that plugs into the brain (You can on that as well, but it's a lot harder because of how small it is and if you remove connections there then the connector gets loose) but the other end with the multiple black connectors.

If you look at the connectors you'll see there's a little black tab that locks the sockets in. You can GENTLY lift that tab just a tiny bit with a razor blade and then GENTLY pull the wire and socket out. Then you can re-arrange them as needed.

Though with your setup you may not even be using that. You'll probably use the Main port for s.bus since it has the inverter on it, Though you may use that port in UART mode if you add a GPS. Or instead of the FLX port if you want to hook up telemetry.