7 Inch AI FPV Drone Build Help

[crimson widget]

Hi guys! As part of my school's drone club and robotics club, we decided to do a project where we would make a drone that could use AI(possibly) to detect objects/targets and fly through them.
Decided on an FPV drone partially because of freedom also partially b/c we will use it as FPV drone as well.
Roughly 1K budget, and we're aiming for a ten inch drone that can hold a rasberry pi and an additional camera + battery. Also decided on O4 infrastructure since that seems really nice.

Kinda need help with all the parts since I'm not really sure what's best given this size...have not done this caliber of drone b4.

[severe dove]

So, given your potential testing durability needs and to lift a PI.
You may be better with a 7in, simply because the props & somewhat motors/frame are cheaper and shorter arms are less leverage and more durable.
Will still have more than enough to cary your pi and other project needs.

Estimated weight of the pi+ other sensors?

[crimson widget]

100g?

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ah okay, i was still thinking 10" is nice because of how long range it can be

[severe dove]

Range is pretty comprable and really more just a payload thing you get when going over 7in.
Plus a certian flight feel etc.
But that's not really the focus of your project.
Either way its up to you.

For a 10in the smallest motor you wanna get IMO is a 2810, but ideally some ~3115's will suit the extra weight better and give you more prop options.
Brother hobby IMO is kinda the best brand for larger motors like this, they have been doing that size stuff for a long time.
Other brands now offer them, but.... IDK i trust the long standing guys more.

you can review the thrust table on BH's site for a given motor and it will help you calculate lift you can reach as well as amps you will need to suit the ESC for.

FC wise, im not too certian cuz you probably want ardupilot and that's not my speacialty.

[high jetty]

i agree, 10 in is overkill

go 7

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u sureee?

here's the specs i have already

[high jetty]

those batteries are a bad idea, go with a real brand like dogcom, tattu, gnb, or maybe cnhl

also if u can avoid it, getfpv and amazon usually overcharge

[crimson widget]

makes sense

[crimson widget]

who would you recommend?

[severe dove]

If you are set on 10in and tri blades.
Get either bigger escs.
Or step down to 900kv.

Arguably both Assuming your project parts it needs to carry is a considerable weight.

[high jetty]

there’s a list of stores in faqs

[crimson widget]

Is 60A not suitable?

Or should I have a buffer

[severe dove]

If the exact prop you were using was in the above test data graph you'd be OK.
Static bench testing is higher amperage than flying.

However, note the above test data is for a 9x4.7x2 prop.
Your shopping list has a 10x5.5x3.
Which will pull more amps.

You risk burning an ESC if your craft is heavy ish and you full throttle with said prop/motor/esc combo.

[crimson widget]

ah okay

[severe dove]

100g is nothing and fine to be dead weight on even something as small as a 5in.
or even smaller depending on how much preformance you want.

but space wise for your pi and sensors etc 7in is probably the sweet spot to have space to work with.

[crimson widget]

actually it’s probably gonna be heavier when we consider it also has a beefy battery

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I do want to continue with 10 partially cuz funni also because long range and I have the ability to carry lots of things maybe even payload

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when considering say a 10 inch would we assume the budget is $1000? Or too low/high?

Excluding controller

[timber panther]

7" max lol, no reason for a 10

Even a 7 is straight up dangerous if your team doesn't have experience with them before

[crimson widget]

okay then

Let's say I still want to go relatively long range(10min+) and have a 150-200g RasPi system on the drone - what frame, motors, and stack would you guys recommend?

[plain burrow]

build a F450 😂
a Pi for object recognition doesn't sound like the best choice either. what framerate are you getting on your visual system?

[crimson widget]

hopefully 60?

[plain burrow]

not a chance

RPi 5 gets <5fps running YOLO

[crimson widget]

💀

is there any way to get higher framerates

i'm (hopefully) not trying to strap a computah type shit on there, maybe computer feedback would work better?

but then with that i run into the issue of the delayed feedback, etc. etc.

[crimson widget]

ANYWAYS....purely FPV drone parts only for a 7 inch drone able to carry payloads of up to 100-200g what would you guys recommend from this message

[plain burrow]

picking the motor is the most important part. i would think a 2806 with like 1200kv
frame and stack you can choose as you like. maby a speedybee v4 stack.
and a LiIon battery pack.
200g isn't an issue at all as a gopro weights ~150g

for AI, looks like there are now add on shields for those tasks. also consider going with an nvidia jetson

also consider how you want to interface that computer to your flight controller. that won't be easy with betaflight.
i would go for Arducopter that has the companion computer sorted out and you can pass high level controls

[timber panther]

https://rotorbuilds.com/build/34142 this is the 7" i just built. i would not pick that frame, but that should give you some specs to go off of. I would pick similarly sized and specced motors, electronics, props, etc

you could go for an even lower kv motor or a lower voltage battery for better efficiency

ill be running this on 6s2p 18650 liion for long range

[crimson widget]

I like speedybee stacks so yeah that makes sense :)

[crimson widget]

yeah, I think one of the hard parts will be connecting the fpv part with the AI part

[crimson widget]

what frame would you recommend?

7 Inch AI FPV Drone Build Help

[timber panther]

Honestly... Source one 7" wouldn't be awful for your use case

Super cheap

Open source cad files so you can design attachments

@crimson widget

[crimson widget]

strong perhaps?

oh wait i remember the source one!

i used a source one for one of my previous drones...nice

[severe dove]

source one 7in
Or
armattan nutria 7in (more $$ but warrantied)

[crimson widget]

yeah, sounds good

[crimson widget]

armattan's quite pricey

[severe dove]

the lifetime warranty is majority of the cost.
If your not gonna be able to make use of that.
Then yeah source one 7in

[crimson widget]

is it one time or

[crimson widget]

also dang 70a?

[severe dove]

one time purchase = lifetime warranty.
just follow the rules about serial numbers and how to make claims.

You are responsible for shipping costs to get new parts from them to you tho.

[crimson widget]

okay

sorry to ask another question but what battery capacity and type seems best for my build?

[severe dove]

probably a 2200mah 6s up to a 3500mah 6s
for a 7in that wants to fit other gear.

You can go larger but ultimately space is gonna be the main limiting factor here more so than weight.

[crimson widget]

how many mins? i was thinking 5-15m is sufficient for me

[severe dove]

entierely depends.
For reference I've taken a light ish 7in with a heavy battery and putzed it around for nearly 35min.
But if you go fast and ask a lot of it youll maybe only get 7min.

~15 should be pretty easy to reach for many 7in rigs.
Assuming you are cruizing and testing your pi project.
Not asking high performance of the rig.

[crimson widget]

nice!

yeah i'm prolly not gonna be zippin with it

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are we talking about the eye watering $500 nano here

[plain burrow]

maby 🤣

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my (school's) wallet's gonna go down the drain

is there a chance i could basically do the calculations and whatnot on a computer, send it to the flightcontroller via arducopter or something, and that would still be (relatively) accurate?

i'm not asking for it to be super quick, just like relatively alright speed

[severe dove]

uhhh, im not sure what you are asking.

sounds like mavlink is the tool you are asking about or would suit your needs tho

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like

[plain burrow]

i guess it's possible. just not with DJI as they don't give you HDMI you can capture

[crimson widget]

do everything on the computer and JUST send the flight controller the directions

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so i would need a seperate camera module

dangit

[timber panther]

just go ws

fuck dji. all my homies hate dji

or something

[plain burrow]

you're not getting DJI and keeping below 1k on your schools budget 😉

[timber panther]

hmmm honestly could get WS and hook the external vrx to a monitor

[crimson widget]

yeah

[timber panther]

if you dont wanna fly fpv

[crimson widget]

i wanna do both

wait question

if the stack has a USB can't i hook two cameras up or something?

[timber panther]

no

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aw

[timber panther]

usb does not mean you can hook anything to it

[severe dove]

yes,
you are looking at a connection made by ELRS or crossifre (ELRS is cheaper and more modern.)
The mavlink will be the protocol or tool that takes computer instuctons and converts them to RC input to be output over the above connection.
then ultimatlly inav or ardupilot on the drones FC will interpret said mavlink directions into actual flight u have asked for.

[crimson widget]

okay so the main issue here then is

dji

[timber panther]

USB, the standard, can handle it, but that board wont support it. its like hooking a usb to hdmi adapter to an old phone, you wont get any image on the other end

although newer phones can which is neat

[crimson widget]

i think i might be trying to do too much here

[severe dove]

If ur only using it for video ur fine.
may have to give up on some OSD elements.
But DJI isn't necissarily mutially exclusive to your other wants.

[crimson widget]

luckily for me, i'm buying this NOT soon

so we gots time

[crimson widget]

so drone -> live video feed -> computer program -> mavlink -> drone

maybe that would work???

[severe dove]

If you need the model to fly the drone then yeah your control loop is gonna look something like that