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Old Jun 07, 2011, 02:24 AM
OlliW
Joined Sep 2009
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Dear Meng,

first, in principle there is nothing to add to my comment, and you know that.

second, please don't assume that we are fools and please don't make a fool out of yourself by repeating these ridicuolus typical "arguments". Such as "and, honest, GA250 is not a good business because it's couldn't earn enough money to balance the cost", yeah, yeah, yeah...

(you can't tell us in one breath that you are a bussiness man and that you are not a bussiness man)

Ok, so we have mutually agreed herewith to talk serious.

I think that Achim is a very smart person, and made a very smart suggestion. In most cases gyros are (or had been) quite expensive, not because of the large material/fabrication costs but because all the development costs have to be rated in (and the good share sellers want to make). This way, however, you will never end up with a high-quality and cheap product. So, I would think that it would be in your best interest to get the software and development for free, because either you will never be compensated for the development costs or you will never be able to develop a product which functionwise will get out of the its-cheap-so-its-ok-if-its-not-working-very-good corner (and even though you wouldn't do that openly I guess we agree that the latter is your problem with the product). No costumer will ever assume that a 10$ gyro will be developed to such a degree that it will function well and safe enough to plug it into a 1000$ helicopter... even a single crash with a HK helicopter because of a malfunction of the gyro will be more expensive than to buy one of the apporved brands from the begining. Of course, there is a risk, but there is always a risk in everything. In this case the fear of risks appears to me as the largest risk. Open source has proven in the past to be able to produce high-end software. You would save money because you would not have to develop the software, you would earn money because you could provide an approved high-quality software. To me it sounds very smart to provide a good and cheap hardware plattform with a high-end open-source developed software.

Now, my 2 cents to my comment and your response "why not make the things sample enough for such guys". In our Western countries we have a particular understanding of intellectual rights. So, your question is at best quite naive.

Furthermore, what you do not seem to understand is that it's exactly because of this sort of behaviour you suggest, which is harming, not me, not you, but people. To make it very specifc. People stop to provide and share information openly, in forums like rcg, but also in society-wise more relevant environments. More concret, I do see this in many occasions happening, that as soon as a chinese is around one starts to be very wary with what sort of information one is sharing. And you hardly can complain about that, because it's your own behavior which way too often justifies exactly this. You may earn a quick buck, but its slowing down your development.

So, since this is a bit OT, I'd like to finish it and repeat,

Quote:
i know that you asian people are always quick with copying others ideas
but of course you are free to proove me wrong by your actions.

Olli
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Old Jun 07, 2011, 03:50 AM
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CHINA
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Quote:
Originally Posted by OlliW View Post
Dear Meng,

first, in principle there is nothing to add to my comment, and you know that.

second, please don't assume that we are fools and please don't make a fool out of yourself by repeating these ridicuolus typical "arguments". Such as "and, honest, GA250 is not a good business because it's couldn't earn enough money to balance the cost", yeah, yeah, yeah...

(you can't tell us in one breath that you are a bussiness man and that you are not a bussiness man)

Ok, so we have mutually agreed herewith to talk serious.

I think that Achim is a very smart person, and made a very smart suggestion. In most cases gyros are (or had been) quite expensive, not because of the large material/fabrication costs but because all the development costs have to be rated in (and the good share sellers want to make). This way, however, you will never end up with a high-quality and cheap product. So, I would think that it would be in your best interest to get the software and development for free, because either you will never be compensated for the development costs or you will never be able to develop a product which functionwise will get out of the its-cheap-so-its-ok-if-its-not-working-very-good corner (and even though you wouldn't do that openly I guess we agree that the latter is your problem with the product). No costumer will ever assume that a 10$ gyro will be developed to such a degree that it will function well and safe enough to plug it into a 1000$ helicopter... even a single crash with a HK helicopter because of a malfunction of the gyro will be more expensive than to buy one of the apporved brands from the begining. Of course, there is a risk, but there is always a risk in everything. In this case the fear of risks appears to me as the largest risk. Open source has proven in the past to be able to produce high-end software. You would save money because you would not have to develop the software, you would earn money because you could provide an approved high-quality software. To me it sounds very smart to provide a good and cheap hardware plattform with a high-end open-source developed software.

Now, my 2 cents to my comment and your response "why not make the things sample enough for such guys". In our Western countries we have a particular understanding of intellectual rights. So, your question is at best quite naive.

Furthermore, what you do not seem to understand is that it's exactly because of this sort of behaviour you suggest, which is harming, not me, not you, but people. To make it very specifc. People stop to provide and share information openly, in forums like rcg, but also in society-wise more relevant environments. More concret, I do see this in many occasions happening, that as soon as a chinese is around one starts to be very wary with what sort of information one is sharing. And you hardly can complain about that, because it's your own behavior which way too often justifies exactly this. You may earn a quick buck, but its slowing down your development.

So, since this is a bit OT, I'd like to finish it and repeat,


but of course you are free to proove me wrong by your actions.

Olli
Dear Olli,

thanks for wrote a long letter to talking about this matter.something you said i agree,something you said i don't agree.

we have no interesting to got any free software or code. we have engineers teams and you know most enginners want build their own projects,not copy.

and, about coax,i just thinking maybe we can do a gyro +mixer+spektrum sat port after read your thread.your work expand my scale,thanks.i always think coax is a toy, we have no interesting to jump in it because most coax need N in 1 and with very low price before(there have under 15 usd coax in chinese market with gyro).now, we have a cheapest MEMS gyro and why not move such project in high end coax,like 450 size helis?

open resource is some good for some items/projects. not all. in my optio, ga250 is not suit to open.maybe we will conside open something in the future,like program box,multi copter controller or something we think it's suit to open.

meng


ps:[/QUOTE]
[/QUOTE]
i know that you asian people are always quick with copying others ideas [/QUOTE]


but of course you are free to proove me wrong by your actions.[/QUOTE]

N in 1 is not a copy idea.

and, in another side,you use our GA250 to do such project,the hardware belong us,it's our idea.you use it, did that means a copy action?
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Old Jun 07, 2011, 04:06 AM
We can rebuild it!
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United Kingdom, Wales, Swffryd
Joined Apr 2010
3,692 Posts
Olli, love this thing you have done! from what I have read here and watched on youtube finding the correct combo of Gyro and mixer are a problem.

Now about the size and weight of this unit, in some of my micro (Toy grade brushed motor) helicopters I would to install a 2.4Gh Rx and a Gyro.... could it be programmed to give a motor driving PWM to which I could connect MOSFETs and drive the brushed motors? Essentially turning it into a 4-1 Gyro, mixer & Dual brushed ESC.
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Old Jun 07, 2011, 04:23 AM
OlliW
Joined Sep 2009
1,994 Posts
Quote:
in another side,you use our GA250 to do such project,the hardware belong us,it's our idea.you use it, did that means a copy action?
LOL... you ignore two most important points, 1) I am openly revealing my sources and 2) I did pay money (to you) for the idea of the hardware. (and BTW if you open other MEMS gyros you find very similar hardware, so it's ridiculous to claim that it's all your idea, if it would be so you should sue your competitors). That's ridiculous and my comment stands still unrefuted.

Anyhow, I think everyone had a fair chance to express their views now, and as the master of the thread I will close the discussion on this topic.

Let's return to the fun part.
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Old Jun 07, 2011, 04:31 AM
OlliW
Joined Sep 2009
1,994 Posts
Hey djdavies83,

well, it probably could, but I think that's exactly what one would not want to do, because units which incorporate gyro, mixer, and PWM output for brushed motors are existing already in abundance, they are known as 3in1. So, if you look for a 3in1 for a coax you will find many options (and some of them cheap). You will also find many DIY projects which describe of how to connect your own MOSFETs to them.

I do not have a good overview of the available 3in1 (I only know the ESky 4in1/3in1), and hence can't give you an advice here, but I know that in this forum there are folks which will know everything about that.

Have fun,
Olli
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Old Jun 07, 2011, 05:27 AM
Professional heli wrecker
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United States, WA, Spokane
Joined Oct 2010
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Quote:
Originally Posted by OlliW View Post
Hey djdavies83,

well, it probably could, but I think that's exactly what one would not want to do, because units which incorporate gyro, mixer, and PWM output for brushed motors are existing already in abundance, they are known as 3in1. So, if you look for a 3in1 for a coax you will find many options (and some of them cheap). You will also find many DIY projects which describe of how to connect your own MOSFETs to them.

I do not have a good overview of the available 3in1 (I only know the ESky 4in1/3in1), and hence can't give you an advice here, but I know that in this forum there are folks which will know everything about that.

Have fun,
Olli
I have to add though to this, most if not all of the commercially available 3 and 4in1's are very poorly built, poor performing electronics. This is why most of the true modders dump the 3in1 right off the bat and go boardless with a separate much higher quality gyro. Even adding your own mossfet chip does not solve the intrinsic gyro weakness nor does it solve the brushless phasing requirements needed for more efficient motors, unless you are ground up purpose building a new system to address these problems. As of yet I have not seen a comprehensive system that has addressed all of these.
Thank you Assan for weighing in here and sharing your opinion. And thank you for supplying a very high quality gyro that we can use and mod to achieve the higher results we require to forward this venue. So OlliW let me ask a quick question since you posted another small required link. This insinuates to me that a simple usb link will not work to program the system?
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Old Jun 07, 2011, 05:58 AM
It flies!!! ... so who cares ?
erdnuckel2's Avatar
Joined Mar 2009
10,048 Posts
Quote:
Originally Posted by OlliW View Post
LOL... you ignore two most important points, 1) I am openly revealing my sources and 2) I did pay money (to you) for the idea of the hardware. (and BTW if you open other MEMS gyros you find very similar hardware, so it's ridiculous to claim that it's all your idea, if it would be so you should sue your competitors). That's ridiculous and my comment stands still unrefuted.

Anyhow, I think everyone had a fair chance to express their views now, and as the master of the thread I will close the discussion on this topic.

Let's return to the fun part.
One little addition - not only the one doing the project pays the money for the "idea" GA-250, everybody who wants to replicate this project through the sources described in this thread AND their own work, ALSO is going to pay money for the "idea" GA-250

If anyone uses this openly availble information to create a new commercial product based on it - even if this person makes a minor change in setup or a slight improvement so that it is no longer 100% identical - HOW MUCH money is OlliW going to "see" for HIS IDEA???

(It has been done here before that a member of the forum introduced an idea, willing to share it with the community, and one commercial follower in this community went and just used it in his/their products, practically identical and without acknowledging with a single word or a thank you that this info was provided - and THAT is why people with ideas and without the means to mass produce them dont like to willingly and openly share them anymore - because someone else is ... based on their possibilities of mass production ... making 'all the money that this intellectual property obviously is worth', without including them in the earning by even 1Cent!!! And of course, its also obvious why the commercial follower never thanked or did acknowledge the info of the member here - because if he had done, he would have been sued for a share of the profits!!!)

Cheap and good is a combination of very desirable qualities. Thanks to the very human nature (ie the inherent greed in so many of the human actions) this combination of qualities gets achieved only in the rarest of cases ...
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Old Jun 07, 2011, 07:28 AM
OlliW
Joined Sep 2009
1,994 Posts
Hey Guys,

I very much appreciate all your opinions and it's an interesting discussion. However, I think we should not expand on this any further here. I'd like to close the discussion on this topic. Thanks.


@Luvmyheli:
One certainly cannot disagree with you on the quality of the 3in1. However, IMHO I find it impressive how well at the low cost they are actually working. They do their job, and without delivering this at a low price I guess the coax heli's would not exist.

Quote:
let me ask a quick question since you posted another small required link. This insinuates to me that a simple usb link will not work to program the system?
I noted that the procedure as it looks (and I am using it) at the moment is very inconvenient, but I promised to look for better solutions, and I think there are better solutions. Unless other folks jump in with their experience, I cannot however provide this solution quickly (I have to test first myself).

I'd like to state before more clearly what has to be done to get the software into the uCs. This, as I suggest it, and I guess most will find most convenient too, consists of two steps:

1) Flash the bootloader
First, a software called bootloader has to be programmed (flashed) into the uC. For that one needs a particular hardware-unit called AVR ISP programmer. In this step one has to solder (up to) 6 cables to the particular pads on the print board and connect them to the ISP programmer. Once the bootloader has been flashed, all these cables can permanently be removed, and in principle the AVR ISP programmer will not be needed anymore.

2) Flash the actual code
Once the bootloader has been installed in the uC, the actual coax gyromixer software can be flashed using an additional piece of hardware, I will call it henceforth the bootloader connector (to have a name for it). In this step the only thing to do is to connect the bootloader-connector to the specified cable coming out of the coax-gyromixer. Since the software may change frequently, because of bugs, or new options, etc., this step will be done frequently. But since one just has to connect to "things" it's easy.

So, you see, to get the things actually working one needs two additional pieces of hardware, the ISP programmer and the bootloader-connector. Of course, for all of this one needs the appropriate PC softwares. However, these come for free and "only" have to be installed on the PC (I am always assuming a Windos CP) .

Now, as I do it at the moment, I have a particular ISP programmer, a serial connection plus the 2-diode+2-resistor network as bootloader-connector. A ISP programmer can be purchased, a serial connection can be purchased too, but the 2-diode+2-resistor-thing you have to do yourself. However, as I said I perfectly understand that this is very clumsy and inconvenient. As regards a simpler solution I am thinking along two lines.

A) Using a FTDI-based USB-to-RS232 converter. These are cheaply available, e.g., at SparkFun.
In principle it is possible to use such a converter to flash the bootloader into the uC. This will be slow, but since this has to be done only once (for each uC) this should not be an issue. This converter can in principle also be used directly as the bootloader-connector without any need of additional diodes, resistors, etc.. (I learned this from Achim, all thanks to him ). Problem only, I have never done any of this myself before (and there could be a problem with the fact that one would operate at 5 V but the GA250 internally works at 3V). If this could be made to work, it would be a neat and most cheap solution. (it will need to pay some attention on the PC software, however)

B) Yesterday I found the Pololu USB AVR Programmer. The nice thing is that it provides BOTH an ISP programmer and a USB-to-serial converter, and it is also of acceptable price.
So, with this device doing the first step, flashing the bootloader, is no problem. Also, the second step should be no problem. However, a bit unfortunate, this device does not allow for inverted output pins. So, it will work for sure as a bootloader-connector if one is willing to add one or two resistors, but it might not work without any additional hardware. As before, I have never used the Pololu USB AVR Programmer. (PC software-wise this will be the most simple solution)


So, a simpler and cheaper solution shall be possible, and hopefully one gets away with only three items, a GA250, a Robbe Box, and a ISP-Programmer-Bootloader-Connector.

Olli
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Old Jun 07, 2011, 05:13 PM
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Germany
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Hi Olli,
Quote:
Originally Posted by OlliW View Post
Hey Guys,
(and there could be a problem with the fact that one would operate at 5 V but the GA250 internally works at 3V)
One remark: on my FTDI board, there is a jumper to configure either 5V or 3.3V.
But to stay realistic: it simply reduces the level from 5V down to 4Vpp () ... But it should do no harm on the GA-250 chip.
Generally i prefer the ftdi usb chip, especially regarding time critical applications, but in my experiance the prolific usb/serial chip will do the job too...
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Old Jun 07, 2011, 10:50 PM
Fix, Fix, Fly, Fix, Fix, Fly
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Colorado
Joined Apr 2009
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Olli, great project! I know it may not seem like there is much interest but I think that E2 is right, most of us are very interested and are just to scared to try it ourselves! Keep the great info coming!

Also, I am getting one of Achim's mixers and will be doing a BLBL conversion. I plan on doing a detailed build log (at least as detailed as someone with my limited skills can do!), but due to funding restrictions it will probably take me 3-6 months to complete the project. I hope that I can do the mixer justice!
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Old Jun 08, 2011, 12:18 AM
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Thanks Achim for sounding in, Olli, thanks also for clarifying those things I needed. Mountainsax please do post up when you get to that point. This is all about common goals being achieved through group effort. We all learn from each other. This thread came along at a critical juncture for me since all the other avenues had already been pursued and achieved. I was dying of boredom. Unless I have at least three projects ongoing with different functions I go crazy.
This actually addresses 4 of my previous builds now that I can upgrade the gyro/mixers.
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Old Jun 08, 2011, 02:48 PM
We can rebuild it!
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Did a 3in1 search..... got a load of random stuff like board games etc, The reasons I ask about brushed PWM on this unit is the price, size/weight and as quality of 3in1 borads that are in the helies at the moment, starnger question.......

Could this unit (once flashed, re-written and hard moddified) take a 3rd input (throttle, yaw and elevator) and give 4 PWM brushed motor outputs? really want to add 2.4Ghz and Gyro to a otherwise great (toy grade) tandem coax Chinook that I own.
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Old Jun 09, 2011, 02:53 AM
OlliW
Joined Sep 2009
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heading hold seems to work quite fine now...

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Old Jun 09, 2011, 11:50 AM
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Quote:
Originally Posted by OlliW View Post
heading hold seems to work quite fine now...

Beautiful! the missing link has been solved. Nice work!
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Old Jun 18, 2011, 09:56 AM
OlliW
Joined Sep 2009
1,994 Posts
Hey folks,

some good news.

It is indeed possible to do all programming and flashing of the GA250 and Robbe Box with only one piece of additional hardware, namely a USB-TTL-serial adapter, plus of course some little things such as cables, a switch, connectors, and so on.

It is important that the USB-TTL adapter uses the FTDI FT232RL chip (other might work but I have and will not check). Such units are available rather cheaply, which means about $15.

Flashing the bootloader via the ISP was in fact no problem at all. However, finding a working procedure for flashing the firmware via the bootloader I found actually not that simple (it at least took me quite some time). The main problem here was the power supply. Using an external voltage source worked very well, but I of course liked to use the internal USB power (to avoid the need of an additional hardware item), and it is here where I encountered serious problems. Apparently, the USB unit disconnects or is disconnected from the PC even upon a slight power drop, which is bad because the connection is lost upon starting the bootloader. As one part of the solution I found it nessecary to connect gnd of the USB-TTL adapter with the ground of the USB connector (these are by default not connected), otherwise things worked extremley unreliable. Not sure why this is so. The 3.3V source provided by the FTDI chip I found way too weak, but with the gnd-gnd connection the USB 5V source does provide enough power to prevent unintended disconnection. However, I didn't wanted a 5V signal level since the Atmega8 in the GA250 is operated at 3.3 V, hence a protection resistor would have been needed, which I didn't wanted to add since then the bootloader adapter cable would have to be different for the Robbe Box and the GA250 unit. Hence, as the second part of the solution, I use the 5V USB source to power the device to be flashed but connect the VCCIO pin of the FTDI with the 3.3 V such as to achieve the 3.3V signal level.

Having said this, it is clear that not every USB-TTL adapter will work for us, and almost always some (simple) modding is nessecary. I used the the sparkfun FTDI Basic Breakout - 3.3V (DEV-09873) board, but here two cables have to be soldered. I have not tested it, but the Breakout Board for FT232RL USB to Serial (BOB-00718) is probably the better choice.

In finding an appropriate USB-TTL adapter, an additional requirement is that it hast to provide, besides the Tx and Rx pins, at least also two of the additional pins, such as CTS and DTR.

Anyhow, with the BOB-00718 I think a reasonably cheap and simple solution is available.

Besides the hardware, also some software such as some drivers and some exe files need to be installed. However, all these software is freely available.

That's it,
Olli

PS: by the way, it appears that the Robbe Box is not easily available in the US. Can you confirm that or could you suggest a good source? Thx
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