SparkFun Forums

[fxmodels]

Hi...
I saw that to use the ArduPilotMega and IMU Shield [and GPS etc...] successfully with a quadcopter setup, you need this Power Distribution Board setup yet I cannot find it anywhere. It is not available. Is this still needed or was this eliminated in a revision to the boards?
Thanks ... trying to sort this all out..
Marc

[esklar81]

Marc,

1) What, precisely, is "this Power Distribution Board setup"?

2) I encourage you to read this guidance before you respond.

Eric

[fxmodels]

Marc,

1) What, precisely, is "this Power Distribution Board setup"?

2) I encourage you to read this guidance before you respond.

Eric

Hi Eric,
Thanks for responding... Not sure why you suggested I read the "how to ask a question the smart way..." Was I asking a question in a non-smart way? I dont get that. I have been asking questions for as many years as the internet has been public and few years while it was still private.. ha ha. But aside from that, thank you very much for taking the time to reply.

This PDB thing is something the Arducopter folks say was needed since I want to be driving a quadcopter and not a standard aircraft. I guess another way to ask this question quite deceptively simply is if the standard Mega and IMU can fly a quad in stabilized flight without any additional circuitry...

Also, to add... I have searched far and wide to find the precise answer to this question and so far there is nothing I found that tells me if I need to distribute power differently for the quad... As simple as it sounds, the answer is elusive.

Thanks,
Marc

[esklar81]

Marc,

1. As odd as it may seem to you, I pointed you to that guidance because it appears that you would benefit from it, specifically: http://www.catb.org/~esr/faqs/smart-que ... #beprecise.
2. How about starting your quest for help here by providing a link to whatever it is you understood to say a "Power Distribution Board" is necessary for quadcopters but not "a standard aircraft"?
3. Why are you asking us instead of the Arducopter folks who referred to a subsystem you can't find?
4. Why, if at all, have you rejected the possible interpretation that you need a "Power Distribution Board" because a quadcopter has four motors or engines, each of which must be "throttled" independently, but a "standard aircraft" is powered by a single motor or engine?
5. I have no experience with either of the ArduPilot boards, but it seems unlikely that either of them can handle the power necessary for flight, so some other device will need to take each motor speed control signal and modulate power to a motor based on it. (That's for an electric-powered craft. For a combustion-powered craft, you might well be able to use a signal from the ArduPilot directly to drive a throttle solenoid.)
6. How did you search for the Arducopter PDB? Just for my own amusement, I thought I'd poke around a bit. It took me only a few minutes to find my way here, from which I was able to get to the artwork for the board and assembly photographs. (The link to someone alleged to be selling the PDB (other than in a kit) does, I concede, appear to be broken. That company's website, though, does appear to respond, so you could e-mail them and ask.)
7. Based on what I found, the PDB appears to be nothing other than a wiring board, so I don't see why it would be required. It might, however, be the most convenient way to distribute power for such a vehicle.

Eric

[fxmodels]

Marc,

1. As odd as it may seem to you, I pointed you to that guidance because it appears that you would benefit from it, specifically: http://www.catb.org/~esr/faqs/smart-que ... #beprecise.
2. How about starting your quest for help here by providing a link to whatever it is you understood to say a "Power Distribution Board" is necessary for quadcopters but not "a standard aircraft"?
3. Why are you asking us instead of the Arducopter folks who referred to a subsystem you can't find?
4. Why, if at all, have you rejected the possible interpretation that you need a "Power Distribution Board" because a quadcopter has four motors or engines, each of which must be "throttled" independently, but a "standard aircraft" is powered by a single motor or engine?
5. I have no experience with either of the ArduPilot boards, but it seems unlikely that either of them can handle the power necessary for flight, so some other device will need to take each motor speed control signal and modulate power to a motor based on it. (That's for an electric-powered craft. For a combustion-powered craft, you might well be able to use a signal from the ArduPilot directly to drive a throttle solenoid.)
6. How did you search for the Arducopter PDB? Just for my own amusement, I thought I'd poke around a bit. It took me only a few minutes to find my way here, from which I was able to get to the artwork for the board and assembly photographs. (The link to someone alleged to be selling the PDB (other than in a kit) does, I concede, appear to be broken. That company's website, though, does appear to respond, so you could e-mail them and ask.)
7. Based on what I found, the PDB appears to be nothing other than a wiring board, so I don't see why it would be required. It might, however, be the most convenient way to distribute power for such a vehicle.

Eric

Hi Eric,
True true... I could have been MUCH more specific. Point taken! ... I had found that page on the Arducopter element you referenced the other day but it is not the one I was looking for. Note though that in that image you can see that the ArdupilotMega and IMU Shield boards are used in conjunction with the board I raised a question about, which of course, is why I asked about it HERE in the Arduino forum. There is another discussion in a forum somewhere that I saw and I actually tried to relocate the TEXT associated with the power distribution board discussion but failed to find it again. The broken link you found, I found yesterday as well. I do not make my circuit boards so I was trying to find out details about how much current it can support. I found pictures but they didnt reference back to what I wanted to show but that is ok. I know now from discussion on another board that the PDB is just a way to forestall having a wire bundle in the middle of things. It is a convenience and not a necessity.
The Ardupilot boards do not ever endure the amperage used for flight they just manage the power output. They are for autopilot and additions of other systems such as GPS etc... They manage in a quadcopter, what would be the "servo" outputs in a fixed wing aircraft. In the quadcopter case there are the 4 ESCs used to throttle the motors and the PDB as it turns out just prevents what could be a rats nest of wiring. Depending on the amperage you expect however, you would need to beef that up significantly perhaps. In my case I would not be able to use the PDB as you saw in that image anyway. So I will have to work out another means.
My questions were tailored to this forum because this is where the question belongs, as I am asking a question as it relates to the Ardupilot boards which are Arduino which is what this forum is for. The PDB is used in conjunction with the ArdupilotMega and IMU Shield so it is proper to ask from the Arduino perspective about usage of such a board in these projects. The Arducopter folks will also answer my questions as well of course and I emailed them yesterday. You said you dont know anything about the Ardupilot board so I understand that you cannot help. That is fine.
Thanks for you help in question specificity though Eric...
Marc

[esklar81]

Marc,

As you appear inclined to misquote me (I did not, for example, say I "dont know anything about the Ardupilot board".) or repeat things I've said as if you were adding information to the discussion, I hereby respond to the only question in your OP:

Is this still needed or was this eliminated in a revision to the boards?

monosyllabically: mu.

Eric

[fxmodels]

Marc,

As you appear inclined to misquote me (I did not, for example, say I "dont know anything about the Ardupilot board".) or repeat things I've said as if you were adding information to the discussion, I hereby respond to the only question in your OP:

Is this still needed or was this eliminated in a revision to the boards?

monosyllabically: mu.

Eric

Eric, you know what? You seem to walk around just waiting to be insulted so forget it. I dont WANT your help with your "as you appear inclined to misquote me" and "repeat things I've said as if you were adding information to the discussion" challenge crap.. I said things I independently found as well but apparently you cannot be bothered to expect someone else might figure something out concurrently.

I ONLY JUST JOINED this board... Thanks for making me feel welcome!!

[elevator4]

my 2 cts., but I can understand fxmodels frustrated reaction here.
E

[shimniok]

Yeah I see the link to buy the PDB is broken. Looks like someone posted in the comments and got a response w/ link:

http://store.jdrones.com/product_p/quadpdpcb1.htm

The PCB files are available... you could always fab your own if it's not too hairy of a layout.

Michael

[Polux rsv]

Fxmodels,

Just another 2cts. I am not a moderator either , but I can say the "welcome message" you received doesn't reflect the global forum spirit.

Probably someone forgot that not every member is an electronics engineer, nor a good editor when trying to express ideas and thoughts.

Angelo

[Chagrin]

I don't see tremendous value to that "Power Distribution Board". It appears to just provide a way to connect a bunch of ESCs with power and with the signal wires from the ardupilot. I'd suggest changing the original "need" requirement to "nice to have".

Here's a picture of the PDB all hooked up:

http://ardupilot-mega.googlecode.com/sv ... APM_RC.jpg

[fxmodels]

Hello guys..
First.. Thank you for the great help here. I very much appreciate your kind words and your advice.

It does appear that the PDB is just a cleaner way to do the task over what could be a cumbersome wire harness. If we were to use one it would have to be remade with much thicker solder traces for higher current draw I think. The artwork is available though as some of you have pointed out so this possibility is clearly doable.

Thank you again for the help!
Marc

FX Models

[fxmodels]

I don't see tremendous value to that "Power Distribution Board". It appears to just provide a way to connect a bunch of ESCs with power and with the signal wires from the ardupilot. I'd suggest changing the original "need" requirement to "nice to have".

Here's a picture of the PDB all hooked up:

http://ardupilot-mega.googlecode.com/sv ... APM_RC.jpg

Point well taken! Thanks...

[Rmagnus]

Fxmodels:

There are several advantages of using a PDB, the most important one is that
By not using so many wires, you help eliminating electromagnetic interference to the quad copter digital compass. A wiring harness can drive the compass crazy very easily

http://www.mikrokopter.com/files/KompassDreht.wmv

Also, not having a PDB can lead to a messy signal and power distribution where many failures can arise, like desoldered joints, etc...

Using a PDB helps in making room for other components like GPS, video transmitter, on screen display, etc...

Maintaining a quad copter with a PDB is MUCH easier

Assembly is much faster.

So my recommendation is : use a PDB

And lastly... I cannot resist saying that I am sorry to see that your first experience on this forum was with someone that clearly belongs somewhere else and evidently ignores what a PDB is for and couldn't even find out about it and finally attacked you.

I just prefer to say: welcome!

[skimask]

^^^^^^^^^^^^^^^^^^^^^^^^^^
A few cases of "need to grow a pair" above