Quadcopter Forum Archive

by Oscar
Published: Last Updated on

T: Quadcopter specs

Q: Hi Oscar the Quadcopter that you have on your site what is the weight loaded and what motors are you using also what props are you using. I am building a quadcopter also and the frame is like yours

R: you mean the mini quadcopter? the weight is about 240g (including FPV gears and battery). motor is Turnigy 1811-2900 and prop is 5030 3 blade props from HK.

Hi Oscar.
As stated above in the subject, I’m a complete newbie to this.
I’m looking at building a quadcopter with a funduino mega and the gy88;

http://www.ebay.co.uk/itm/10DOF-IMU-MPU6050-HMC5883L-BMP085-Flight-Control-Gyroscope-Acceleration-Compass-/181273694159?pt=AU_B_I_Electrical_Test_Equipment&hash=item2a34c10fcf

http://www.ebay.co.uk/itm/161200042555?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

I think I have got my head around the programming of the funduino and the gy88, but what pins / i/p do I connect the remote rx for yaw, roll pitch and so on?

I’m thinking of the flysky fs-thx9 tx and rx for option extras at a later date.

Any advice on making the quadcopter, as-in, a general size for a carbon frame in proportion to, motors “motor size and rpm”, propellers “size and pitch”, esc’s and becs if needed?

I’m good with general engineering, grp and electronic, but the arduino thing is new to me and I find the xcopter ecal somewhat misleading.

I’ve read through most of your quadcopter pages. They are a fantastic source of information.

I hope you can provide me with some advise.

KEEP UP THE GOOD WORK.

Dizzwold.

 

Hi Oscar,

Awesome blog and very informative. I am a complete newbie also. I was considering buying a quadcopter with gps, 2 axis gimbal, go pro camera, and FPV. But after doing a bunch of research, I decided that I am going to build my first quadcopter. Your blog has given me a lot of things to consider. I would like to design my quadcopter so I have the ability to add on components such as gps, a 2axis gimbal with a go pro camera, and fpv later. My goal is to learn how to fly it well and then add on later for Ariel photography.

I was considering using a carbon fiber frame or fiberglass frame. I was wondering what frame size would be best for later adding a 2 axis gimbal. This frame from actually comes with a gimbal with motor and a controller, although the specs do not list the weight.

http://www.goodluckbuy.com/locust-quadcopter-frame-and-2-axis-gopro-3-aluminum-gimbal-bgc-3-0-mos-controller-for-fpv.html

Do you have any other suggestions on a frame?

I also was wondering which flight controller to use. This one from the site you linked already has a gps module included.

http://www.hobbyking.com/hobbyking/store/__26588__MultiWii_PRO_Flight_Controller_w_MTK_GPS_Module.html

Any feedback would be greatly appreciated. I am looking forward to doing this project with my son (age 9).

 

 

Hi Brian, if you just started, I would recommend the KK2.1 as flight controller, it’s easy to setup and tune without a computer. Search for KK2 in my blog for a review. Although tt cannot handle GPS, it’s a good controller to start with, and it can be a good backup. Later you can upgrade to APM2.5 for GPS application.

About frame size motor to motor distance should go higher than 330. 450 and 550 are also good, personally I found the larger frame, the more stable it is. It also depends on how easy you can find replacement arms for, and how tough the frame is. Carbon fibre is a good choice, I am using it on my tricopter and never had a broken arm (not yet ).

Start small. You don’t have to buy everything at at once. You will learn more what is best as you progress.

When you first build you quad, keep the number of components minimal, don’t worry about anything fancy like the gimbal. Learn how to fly first, then add the FPV gear, learn how to fly well just by looking at the goggle or monitor. Being able to fly steady contributes to good video quality too!

 

Oscar,

Thanks for the response. Even before reading your post, I had decided to scale back my first quadcopter project. I am going to do a basic setup. I am planning on installing GPS. This is going to be a fun father-son project. He is 9 years old so I thought the added stability of GPS would help his (and mine) flying skills as well as reduce the repairs.

I like the DJI Naza M lite flight controller which comes with a GPS kit for $169. I still think the KK2.1 is a great deal, but too bad you can’t add GPS.

I have decided on this frame which as an integrated PCB.

http://www.rctimer.com/product_656.html

Now I have to calculate my weight to size the motors and battery. I will let you know how things go.

Thanks again for the informative blog.

Brian

 

 

Hi Brian

you are welcome, have fun building and flying this quad with your son!

I would love to hear how you get on with your quadcopter too!

best wishes
Oscar

 

 

The connection should be pretty similar to how you connect it with the Arduino NANO.

Here is a reference image I found on the internet, how people connect their Mega 2560 to other electronics.

If this is the first time you build a quadcopter, I strongly recommend getting a KK2 flight controller as well, as a backup, and a benchmark, so you have something to check your hardware (frame, motor, ESC etc), and a good benchmark to how well is your DIY flight controller works.

About the motor size and power, it really depends on what you want to do with it. For example, when I was designing my Mnin quad, it was just for flying around for fun, and i wanted to attach a mini camera for some recording, like the 808 keychain camera, I was looking at a total weight of around 200gram to 300gram. Double that, and divide by 4, would be the thrust required for each of the motor, so that is 150 gram each at 100% throttle.

Find the right motors for the job, then you can find the prop for these motors.

In fact, check out my post about how to choose motor and props.

Hope that helps
Oscar

 


I have been flying the phantom but now want to build from scratch. (my friends are use to me making everything myself and I hate saying “no” when they ask if I built it)

I read your blog and have figured out how to calculate the thrust required. I am thinking that I need about 3.5kg of thrust. Looking over the wide variety of motors and props, I am left no further along. Is there a way for a less educated guy like me to determine what would be a good starting point for picking a motor and prop? A lot of the discussion I am finding online is way TF over my head. Any guidance would be greatly appreciated.

Actually, it’s 3.5kg of thrust. My payload (if that’s the same as overall weight of the quad) will be somewhere between 1.5kg and 1.7kg. What you offer is good advise though. I never even thought about looking at the datasheet (ironically, I am a bit of an electronics hobbyist, so not sure why that never occurred to me).

Thank you. I tend not to explain myself well, so it’s rare that I get a response.

 

R:

HI,

3.5KG of payload? that’s a lot! Are you going to use your quad to deliver goods? haha that means you need at least 1KG – 1.5KG of thrust per motor! I think you should consider shrinking the size of the quad, and get rid of weights you don’t need!

Anyway, don’t worry about props before choosing a motor. Most of the time you are recommended what kind of prop you should use with the motors, or you should be given a table of statistics showing data like “thrust”, “current draw” etc… Then you should be able to decide on what prop you need.

If you don’t know much about RC motors yet, I recommend you to go to the RC online shops, and go through their motor products. I don’t know if you know Hobbyking? it’s a famous RC online shop, and they provide a really good tool to help you identify the kind of motor you need.

http://www.hobbyking.com/hobbyking/store/brushless_motor_rc_data.asp

although you can’t choose the range of thrust you need, but for your case i think the condition should be:
Kv 100 – 800
weight 50 – 300
Max Current 20 – 50

you can probably ignore the rest, and go through the result.
For example the first result i got was NTM 750kv motor, from the datasheet it says it can provide around 900gram of thrust with 10×5 props and 4S battery. Clearly that’s still not strong enough for your goal, so you can move on to the next one.

Just to be clear, I am not getting any money for promoting hobbyking, and you don’t have to buy anything from them. But I just find the tool you provide is quite useful.

Also google the motor you find suitable, see what people’s comments are, don’t solely trust the review on the seller’s website

Hope that helps, and have fun shopping !


 

Q: Hey Oscar,
What do you think about using these Li-Ion batteries for my quad?
They have a 2C rating, is this too little for the brushless motors?

They are really light compared to the Li-Po batteries, and only fall short at the Discharge Rate?
What would you say?

R:

sorry I don’t know much about these battery.
It depends, first to know how heavy is quadcopter, how much thrust is needed to lift it, x2/4 (times 2 then divide by four), to get how much thrust required for each motor.

now to achieve that thrust, how much current will be drawn? times four to get the total current draw from battery.

I think to calculate the max current draw from battery, you multiply capacity with C rating, see if that meet your requirement.

Of course, further testing will be required.


 

Q:  Hey Oscar,
Thanks for the great site and resources, really appreciate it.

Have you ever tried implementing the flight controller algorithms yourself?
For features such as self-levelling, altitude-hold, etc.?

I am really interested in learning and implementing this especially.

I am on a tight budget, so I was planning to build a cheap quad from scratch to try and write the software for it
So I want to build my own flight controller with an arduino, and IMU.
My question is, can the arduino process all the info from the IMU quickly enough to effectively be able to carry out the functions such as self-levelling, etc.?
Also do I need anything other than an arduino and an IMU to build my flight controller?

R:

It’s a incomplete project. I don’t have time at the moment to do it. Maybe in the future!

Check out Multiwii if you haven’t. It’s an open source project based on Arduino, could be a good starting point.

If it’s not a must, I would recommend to buy a ready flight controller, it’s not too expensive compared to a DIY arduino Flight controller. It could also be useful to compare the performance, if you build your own DIY FC in the future.


 

Hi Oscar,

I am building my first quadcopter and I’ve picked out all the components so far but I am starting to have second thoughts on my choice of ESC. Currently I am going with the Turnigy Multistar 30A ESCs and I am wondering if it is crucial to flash the simonK firmware onto them?

Do you have any experience with these or a similar ESCs? Could you recommend an esc which works well without the simonK firmware?

R:

It’s not crucial at all.
It should be totally flyable with default firmware.
The simonk firmware is only when you want to get more performance out of the ESCs. I doubt you are going to notice the difference if you are new to the hobby.

I like the Hobbyking ones better (blue heatshrinks), no special reasons, just because I have used them before, and never had any problems, and they are cheap.


 

some one asked me a question privately, so sharing my response

Hi Oscar,
I heard that you use GoPro on your ZMR250. I’m planning to build one and I’d like to ask for your advice.

My intended setup is
DYS 1806 2300kv motors
Emax 12A ESCs
5×3 prop
Naze32
FrSky rx
GoPro
Fatshark vtx and board camera

Total AUW without battery is around 520 530g. I’m choosing the battery now and i was wondering if you could share your set up, weight, flight time, battery size and any another advices etc.

Thanks


Hi! Yes I am using Gopro on my quad.

that is a pretty good setup you have there. These motors can generate 370g of thrust (from other people’s stat), so it gives you total around 1480g. So if you can really keep the weight down to around 700g, you should still have 2:1 power ratio in theory, that’s going to be a nice powerful machine!

Depends on what you are after, sports racing? or just stable FPV? pick a light, high C rating 1300mah if you are into doing racing, pick a high capacity lipo if you want longer flight time and stable FPV, like the 1800mah or even 2200mah.

It’s all fine, as long as you can make sure “Capacity x C rating” is larger than the possible max current draw of your quad (which I always assume 48A, the size of your ESCs, just to be safe)

I never used these motors before, so I don’t know how true these stat is. You could even consider running 6 inch prop, to give it a bit more lift. But check first see if that’s safe for your ESCs.

thanks for the advice. I already have a flip 360 for nice stable fpv so I’m going more into sport flying, but I still want to get around 7-8 mins flight time so would you suggest a 1500mah 3S 35C?

It’s tough to tell how much flight time you are going to get, since I have a completely different setup. Maybe check with someone who is using a similar setup as yours.

But my guess is you are likely to get 7-8 mins hover time with 1500mah, maybe 5-6 mins of flight time?

if you are going to be doing racing style flying, try your best to go light weight, when you crash hard, the impact would be smaller. Besides, 7 to 8 mins of intense fast fly is very energy-draining, so long flight time isn’t always a good thing I found!

Thanks for the advice. I think I have a good idea of what to go for now.


 

Q:

I have been working on coming up with a parts listing I need to buy for my first quad copter and I have been using your post on your Mini-Copter build as a model. I was going to use the kk2.1.5 instead of the acro board just because in another one of your post you said it was easier to setup for people that are inexperienced in working with quadcopters. I know that I will need to add a voltage regulator and smoother for the fpv gear. My question is what else was left out of the Mini-copter build like what things are needed to change the firmware. I have read must of your tutorials and I just want to make sure I am not going to buy anything wrong or not enough of anything because my budget of under $400 is pretty tight already. My spread sheet containing the parts I intend to buy if everything goes well can be found herehttp://goo.gl/fWEcV6. Also I was wondering if anyone had any ideas on how to make it any cheaper?

R:

don’t worry about the firmware flash for now, everything should work straight out of the box, you can make the improvement later on as you go along.

we can’t see your list, it asks for permission, maybe copy and paste your list down here.

Q:

Ok sorry about the list it is fixed now. Stupid school required their domain to view I fixed it. Either way
Diatone FPV250 Frame $9.99
Cobra 2204 1960KV (4) $83.96
12A Blue Series ESCs (4) $33.20
Gemfan 5030 Props (2) $2.62
Naze32 with Multiwii $24.99
Frsky DJT Transmitter $23.00
Frsky D4R-II Receiver $21.40
Turnigy 9X $59.99
Super Simple OSD $9.05
ImmersionRC 600mW VTX $69.99
Turnigy Nano Tech 4S Battery 1300mAh $18.55

R:

looking good!
make sure you are getting little things, like heatshrink, XT60 battery connector, wires for power distribution etc…
also get some more props, at least get 4 sets each, if not more.


 

 

Leave a Comment

By using this form, you agree with the storage and handling of your data by this website. Note that all comments are held for moderation before appearing.

2 comments

Michel 21st January 2015 - 9:29 am

Hey everybody! Seems to have knowledgeable people here on multi rotors, so I take my chance! :)

For a professional use, I am starting a building with a DJI S900, with this equipment:

DJI S900
ZenMuse GH4
DJI A2
IOSD MK2

All of this piloted by a futaba T14SG, and I also have a 6S Lipo 12 000 Mah battery. Do you think it is enough to fly during 15 minutes? Some say yes, some say no, and it makes me not quite sure by the way! I take some explanations if a kind people want to give some.

The second point is, I want to fly as safe as possible with the machine and I often heard about bugs on DJI A2. Do you know this problem? Then, i ‘d like to equip the aircraft with a rescue parachute system, as those we can find at DJI with the dropsafe, or again, the rescue kit for DJI S900 from Opale Paramodels. Do you know these products and do you think they’re really reliable? because it seems really interesting products to protect a machine like the S900, the video displayed by Opale Paramodels is really convincing to me, i don’t put a link because I don’t know if it is allowed or not.

I hope my explanations are good (not an english native) and that some people wille take some time to answer me.

Cheers!
Michel

Reply
Oscar 21st January 2015 - 10:08 am

Michael, the forum has been closed and archived.
Please join this discussion group on facebook, and repost your question there and hopefully someone with experienced can answer your question.
https://www.facebook.com/groups/Copter.Fans/

Reply