IFly4 Quadcopter and Rabbit Flight Controller ARF Set Review

[teslahed]

I found a very interesting review of a Rabbit powered IFly4 Quadcopter.

http://fpvcentral.net/2012/05/i-fly4-rabbit-flight-controller-review/#comment-4673

It also covers some of the code violation issues in more detail with a small amount of new information.

I've got one of the rabbit boards on order. I intend to use it for an FPV quadcopter because i have heard they are particularly good for stable flight which is what i need for that. Timecop has pretty much admitted coding the best possible stable level mode for MultiWii isn't a priority because he (and i presume the other developers) find that kind of flight boring (fair enough - so do i - unless it's for FPV) so my choice is limited.

I'd feel much happier about that purchasing decision if the code wasn't in violation of the GPL though. I would have thought an active community able to write code in support of the rabbit would only increase it's longevity.

[Gaza07]

I've already seen that web site and I still don't see any concrete proof there either, there has been a huge row over on RCG that has just got silly and out of hand over this subject, When the rabbit first came out I really liked the look of it but held back from buying one because of this very reason, but after following the war over on RCG and neither side really making any valid points or providing any sort of concrete proof I bought one, and I have to say it is one of the best boards Ive bought to date,
All I can really say is and I'm not going to start an argument with anyone about this, don't follow what was basically started by one person and then other people just jumped on the band wagon,
What is really needed is a independent third party to look at this and then say if there is really a violation, and not some one who knows programing and might well be biased saying go and decompile it your self and see, when they know full well it is just going to look like a load of rubbish to a non programmer, why dont they list the violations with clear pointers and explanations as to what is copied, and not just say there are similarities and expect us to take their word for it,

I fully agree that if the rabbit went open source it would actually sell more and would be very good for all, who knows maybe one day it will, but for now its not and all I say is don't get pulled in to the bull that's gong about and enjoy your purchase   

[teslahed]

What is really needed is a independent third party to look at this and then say if there is really a violation, and not some one who knows programing and might well be biased saying go and decompile it your self and see, when they know full well it is just going to look like a load of rubbish to a non programmer, why dont they list the violations with clear pointers and explanations as to what is copied, and not just say there are similarities and expect us to take their word for it,

I fully agree that if the rabbit went open source it would actually sell more and would be very good for all, who knows maybe one day it will, but for now its not and all I say is don't get pulled in to the bull that's gong about and enjoy your purchase   

Personally i find the evidence shown so far quite convincing, but the problem is if you (like me and most other people) aren't a computer coder you are reliant on the interpretion of those that are.

I think one of the reasons that things got so nasty on rcgroups is that people started making personal attacks on other people who had purchased the board rather than keeping things to a discussion of the issues around the flight controller itself.

I'm not about to start a flame war against people who've bought the rabbit. I've bought one myself so that would be a bit odd. I just thought there was a lack of decent info on the subject so posted the link with the review in it when i spotted it.

The writer of that review states he is not part of the MultiWii team and that he's seen enough evidence to personally convince him. He could be mistaken or lying though as could the people on the multiWii team. Personally at this point, having read what I've read from a few different places, i don't think they are making stuff up.

I just did some more reading and found this interesting link;

http://www.multiwii.com/forum/viewtopic.php?f=8&t=1142#p8052

[Gaza07]

I think the problem here is the fact it is decompiled and that from what I can see involves some guessing on the part of the program used to decompile it, look in the bottom right of the decompiled code in the link you provided, does the decompiler have to follow a set of rules written in to the program that may make the code seem similar or is it the programs interpretation of the code, I don't know as I'm not a coder either, and the people doing the decompiling are looking for any similarities to try to prove their point, all I see are a few lines that may or may not have been copied its hardly the whole firmware, also some of the hardware used on the rabbit has no code in multi wii

I'm not saying there is no violation as Im not qualified to do so but, at the same time I find a few lines of decompiled code hard to take as evidence,
In all honesty Im sitting on the fence on this one and just hope the rabbit dev team release there source code and put an end to the arguing one way or the other 

[teslahed]

I'm not saying there is no violation as Im not qualified to do so but, at the same time I find a few lines of decompiled code hard to take as evidence,

The impression i get is that with code there are so many different ways to do things that when you get similarities cropping up that's a strong indicator that people have copied each others work.

Also the multiwii team claim that the methods used are very similar in places as well as individual lines of code.;

Motor mixer is definitely 100% multiwii, down to using same macros etc, and a lot of other things like reading/saving settings, main loop, uart organization, etc seems to follow multiwii code patterns.

(taken from post in previous link on multiwii forums)

But again we are reliant on the interpretation of people who know more about the subject than ourselves. If you can't recognise patterns in code you are not going to be able to see or understand it for yourself - i can't.

And i totally agree that the arguing that ended up taking place on rcgroups was unnecessary, unproductive and unpleasant. I hope i can keep things on track with my comments to avoid such pitfalls and keeps things strictly impersonal regarding any criticism of the flight control board which I've got on order (might arrive today if I'm lucky - it's certainly overdue anyway).

In all honesty Im sitting on the fence on this one and just hope the rabbit dev team release there source code and put an end to the arguing one way or the other 

I'll keep my fingers crossed too.

[Gaza07]

I knew at some point on the forum this subject would crop up and I welcome an open and friendly debate / discussion about it and nothing you have said could possibly be taken in the wrong light, every one is entitled to there opinion, (even if you are wrong  ) sorry just kidding 

The impression i get is that with code there are so many different ways to do things that when you get similarities cropping up that's a strong indicator that people have copied each others work.

If the similarities are in the source code which we have no access then yes its copied but, what I was getting at was could the decompiler be interpolating the code and not actually showing exactly as it was coded, I wonder if the decompiled code could be recompiled and actually work

[teslahed]

I knew at some point on the forum this subject would crop up and I welcome an open and friendly debate / discussion about it and nothing you have said could possibly be taken in the wrong light, every one is entitled to there opinion, (even if you are wrong  ) sorry just kidding 

That's reassurring to hear, thanks. I'll be the first to admit i could be wrong on this 

If the similarities are in the source code which we have no access then yes its copied but, what I was getting at was could the decompiler be interpolating the code and not actually showing exactly as it was coded, I wonder if the decompiled code could be recompiled and actually work

I think my knowledge runs out at about this point. My only answer is that i have to believe the people running the decompiler are not deliberately trying to mislead me into believing that there are similarities when there aren't - i would imagine the MultiWii people have better things to do than make stuff like this up, and i expect they are competent enough not to make a mistake like this by accident. But that's just me guessing.

The fact there is now a third party interface program being coded for the rabbit;

http://www.rcgroups.com/forums/showthread.php?t=1661104

Is somewhat reassuring. I can only hope that the rabbit developers see that opening things up means other people work on their project for free generating more content and sales.

[Gaza07]

I have been downloading and using the new Gui and it will be a big improvement on the original one  but it is still a beta and not every thing works as it should yet, there is a new feature in the new 1.212 firmware that allows you to wind up your motors and gives you a vibration reading which is very useful, they say a reading of 10 or less is fine, I haven't tried mine yet,

The thing is to be able to code this new interface the rabbit dev team released the communication protocols used on the rabbit which some people see as the first step towards becoming open source as even this was kept from the users at first,

That reminds me I must make a thread in the rabbit forum for the new Gui I held of doing that untill now because the alpha releases didn't really do much

[MadMax]

It makes a change to see a peacefull discussion about this and some good points raised,
Ive seen some real nasty arguing over this and people being banned from forums 
I don't really have an opinion on the matter as I  don't have any knowledge of coding or any such things, although I doubt it would prevent me from buying a rabbit just not sure wether to go loppy eared or not  sorry I couldnt help it how do they come up with the names for these things, its a flight controller for flying lets call it an eagle or a buzzard no we prefer rabbit 

[teslahed]

its a flight controller for flying lets call it an eagle or a buzzard no we prefer rabbit 

I always thought that too. I wonder if the rabbit is some kind of 'lucky' animal?

http://www.chinahighlights.com/travelguide/chinese-zodiac/rabbit.asp

[MadMax]

You might be on to some thing there but looking down the list in the link you gave why on earth didnt they choose tiger or dragon even rooster might have been better than wabbit 
Although it could have been much worse they could have gone for pig 

[teslahed]

You might be on to some thing there but looking down the list in the link you gave why on earth didnt they choose tiger or dragon even rooster might have been better than wabbit 
Although it could have been much worse they could have gone for pig 

Actually now i come to think about it if you orientate the board in the right way the pins coming out the side look a little bit like wiskers, the LEDs along the top could be hair and the USB connector at the bottom a little mouth. You've got to be trying pretty hard to see it though - so perhaps rabbits are lucky too.

[MadMax]

And I thought I was nutz 

[Gaza07]

The first thing I noticed when looking at that board was there is not baro or compass fitted 
and even when I squint I cant see any type of animal 

[teslahed]

Don't worry - that's just a random picture of the board i found with google images. They haven't sent me the wrong flight controller (actually it didn't arrive today anyway so i haven't got it yet).



I'm not going to win any awards for photoshopping but you get the idea

[Gaza07]

You must be a mind reader because I was actually thinking I hope thats not the board hes waiting for as it got no baro  ;D
that reminds me I must remember to make an appointment to see the doctor 

[MadMax]

I want some of what teslaheds on  ;D

[teslahed]

In other rabbit related news; i just contacted goodluckbuy using their online help tool because my rabbit flight controller hasn't arrived yet that i ordered on 26/06/2012.

I have been told that they are out of stock and it could be 20 days before they get new ones in. It's the new version with the high precision barometer that has run out. I'm guessing '20 days' is just an approximation for 'a while'. I used the online chat tool and they've said they will refund me.

Somehow when clicking through on the order i managed to order 2 of them Goodluckbuy only had one of the orders on their records until i gave them the paypal transaction IDs. No idea how that happened but i got that sorted at the same time.

So far it seems that goodluckbuy are pretty good on customer support as long as you are happy to use the online chat help thing and have a little patience.

They've still got the old ones in stock though;

[Gaza07]

GLB are a good place to buy from except when they are out of stock they still keep selling the stuff, they realy should mark things out of stock and stop you adding it to the cart, are you going to wait for the delivery or have you had the refund, you can get the boards from love flight via ali express but you have to pay by card and there is the risk of duty, I had to pay over £20 when mine came from them, they ignored my messages about marking the value down and put the full amount on it 

[teslahed]

GLB now have the high precision barometer version of the rabbit back in stock.

I know this because i just chatted with them up to ask why they'd only refunded me for 1 of the two rabbits I've had on order for the last month. Apparently the reason is they came back into stock so shipped me the other one out yesterday. Which is nice actually - I'm looking forward to having a play with one. It would have been nicer if they'd mentioned this without me having to contact them but you can't have everything

[Gaza07]

They wont have stock for long because it was posted on rcg yesterday that love flight have no stock 
so you have 2 rabbits coming then ?

[teslahed]

Nah - just the one. I had two on order, they cancelled and refunded one when the stock ran out but didn't refund me the other - I've just found out this is because they came back in stock so posted me that one out the other day.