New multicopter, some advice needed (pixhawk or APM2.6)


#1

Recently I got as a present a Q650 frame and a set of 4 850Kv motors, 22A ESCs and propellers. I have an old Futaba 6-channel radio transmitter, ~5000 mAh LiPo 3 cells battery and a LiPo charger as well.
I was wondering which additional parts I need to finish to set up of the quad-copter. I have read that the APM 2.6 will be superseded by the new Pixhawk. The general consensus that I have found reading in forums is that it is worth to go for the new Pixhawk, but I might be wrong.
If I am not wrong I would need the Pixhawk, a PPM encoder to connect the receiver with the Pixhawk, an external GPS module, and, optionally, a telemetry kit in the future. Is there any other additional cable or part needed? Are the external buzzer, switch, cables, etc., included with the Pixhawk?
Another option that I am considering is to buy an Arducopter IRIS (depending on the price) to get familiarized with the multi-copter concept and later reuse the parts on the Q650 frame if that is possible.
Any advice will be appreciated. Thank you!


EasyDrone - APM powered RTF drone
#2

Hi

I think you will only need to buy a fight controller with GPS to get things working as you can use your Futaba radio (although if it does not have a 3pos switch, you might be limited 2 flight modes you can set-up for each flight) Other usefull addon would be a telemetry kit. The Pixhawk kit includes the buzzer, switch, power module etc…

Your idea about getting an Iris is fine as the iris is ready to go and comes with a PPM enabled radio. But this would only be recommended if you dont have any experiance with RC stuff, as building a quadcopter yourself and getting it setup is not too hard, just takes abit of time and will save you abit of money. But the Iris still is alot of fun and a nice frame.

APM2.6 or the Pixhawk?

As of now the Pixhawk and APM2.6 both run the same software which will be the case for some time. Pixhawk has a more powerful processor so will give developers more freedom to add more things so in the future it will have more features than the APM 2.6 board, but the APM2.6 board will still be supported for a long time.

Both Pixhawk and APM will need the GPS/Compass module. But I think you will need a PPM encoder with the pixhawk with your Futaba radio (but check the manual to see if your Futaba supports PPM)

  • Advantages of APM2.6 - it its smaller, cheaper and does not need a PPM encoder
  • Advantages of Pixhawk - more powerfull (might not need a PPM encoder if your radio supports PPM)

If you have any other questions, please let me know


#3

As I understand it Arducopter on the APM2.6 is now at the end of development potential, it uses every byte of available memory and all the available processing power so nothing can be added to it without very extensive memory freeing which is unlikely to be done and even then it may not be possible without interfering with existing timing loops… By the way, I understand that Arducopter is the most complex software ever written for the Arduino platform.

The Pixhawk has much more memory available and also much more powerful processing, therefore has plenty of room for expanding the Arducopter software in both respects.

Basically APM2.6 at this moment will give you exactly the same as Pixhawk, however AMP will never be improved upon with regard to Arducopter where Pixhawk is at the very start of its development cycle - Much more future proof :wink:

I have the IRIS and was intending to do as you suggest and cannibalise it to upgrade to a bigger hex or octo, luckily I got a developer edition so got a free retail release pixhawk and decided against it. If you buy an IRIS you will only save the cost of pixhawk, gps and telemetry and so would pay near on £600 to save £300.

I decided in the end the Iris was too good a toy to just hack it to bits so I am keeping it and building a Q800 along side it - Just need motors and esc’s now I think:)


#4

I do agree with @Louise about APM2.6 running at the limits of the Atmega 8bit processor. Although there is not much room for improvements due to the code at its limits, it will still be supported and if there is a feature that can be added it will be.

Look at the first APM that was based on the ATmega1280, when it reached its limits, APM then moved to ATmega2560 which the APM2.6 still uses, but the ATmega1280 was supported for almost a year after it was no longer made. Similarly APMv1 was still supported a long time after APMv2 was released. But that said there is big CPU difference between APM2.6 and pixhawk so I dont think that many new features will be added, but I am certain it will still be supported for quite some time.

But still best to go for pixhawk if you can spare the extra bit of money as it is more futureproof :wink:

Just for fun, here is the pic of the first APM board/kit


#5

Supported… that is a different thing to upgraded I guess.

There are people still using APM1, and like a PC it is only really outdated if it does not do what you want it to do. In that respect given that APM2.6 controls a multi near perfectly well - and without a doubt a whole lot better than I could without it - then it is good for many years, I could swap the pix in the Iris for the apm2.6 and the Iris would fly the same and be just as flyable in 5 years as it is today.

It is hard to imagine what more can be done to improve upon it really, but then again only a few years ago it was hard to imagine we would have an affordable autopilot with gps navigation and myriad of other features at all. It is all very fast paced, so in that respect I think the best choice is the latest offering not because I think the apm2.6 will be useless in a year - it clearly will not.