DIY avionics (Was: Micro with CAN + drivers)

Dave Nadler wrote:

>Looks nice !
From a distance.  When you get close you begin to notice the calluses
and warts.  It is sill a good airplane.

>Here's my front office view:
>http://www.nadler.com/public/YO_FrontOffice.JPG
>Top center instrument (I designed) uses RS485

You mean the yaw string?  ;)
[ The ILEC in the panel looks nice too. ]

>Maybe a dumb question, but given your intentions here
>regarding the display device, why not BlueTooth ?

Thought about it, and may try it in early versions to save some wiring
and development effort on the display side, but I doubt I'll use it in
the final system.

I believe (prejudice, not research,) that the fully wired CAN version
will be much more reliable. (1) [ "Tower, experimental on final is
going around - need to pair my instrument panel with my pitot again."
- Note I am trying not to say re-pair ]

In a sailplane you can expect all the electronics to be clustered in
the cockpit, and to have few or no sources of interference.  (Radio
mostly in receive mode, FLARM? )

I have to locate the sensors in the outboard sections of the wing, to
keep them away from the prop's stream and engine influence.
Again, there are double CDI ignition systems, transponder.

How does bluetooth work in this environment? What is the effect of
other people walking around the plane with bluetooth enabled devices
while in the ground?  Probably it can be made to work reliably, but I
read enough stories of people having trouble using their bluetooth
phones with their bluetooth car stereos.
I'd rather avoid the extra R&D effort and stay with CAN.

>Keep us posted !

Will set up a web page when I have something to show.

So far I ordered the following:
1 x ArduIMU
   <https://store.diydrones.com/ArduIMU_V3_p/kt-arduimu-30.htm>
1 x Android Open Accessory Dev Kit
   <http://www.embeddedartists.com/products/app/aoa_kit.php>
3 x LPCXpresso boards
 <http://www.embeddedartists.com/products/lpcxpresso/lpc11C24_xpr.php>

plus a Dell Streak 7 tablet I already have.  No GPS on the first
stage.
The Xpresso board can be split into the processor proper half and a
debugging / JTAG programming half.
It is inexpensive enough and small enough that I doubt I'll design my
own boards.

The only major ingredient missing is free time. I am working on
getting the plane itself back in the air, steam gauges and all.

R.

(1) Excluding a few weak links like the USB connector in the
tablet(s).  
--
Roberto Waltman

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On Wednesday, August 8, 2012 5:18:40 PM UTC-4, Roberto Waltman wrote:
> Dave Nadler wrote:
> >Here's my front office view:
> >http://www.nadler.com/public/YO_FrontOffice.JPG
> >Top center instrument (I designed) uses RS485
> 
> You mean the yaw string?  ;)

I know, I can't manage to take pictures and while
keeping the yaw string centered. Perhaps if I
chewed gum...

> [ The ILEC in the panel looks nice too. ]

Thanks ;-)
Normally there's more useful info than a blank
map page...

> >Maybe a dumb question, but given your intentions here
> >regarding the display device, why not BlueTooth ?
> 
> Thought about it, and may try it in early versions to save some wiring
> and development effort on the display side, but I doubt I'll use it in
> the final system.
> 
> I believe (prejudice, not research,) that the fully wired CAN version
> will be much more reliable. (1) [ "Tower, experimental on final is
> going around - need to pair my instrument panel with my pitot again."
> - Note I am trying not to say re-pair ]
> 
> In a sailplane you can expect all the electronics to be clustered in
> the cockpit, and to have few or no sources of interference.  (Radio
> mostly in receive mode, FLARM? )

FLARM always transmitting but low power, transponder at very high power.

> I have to locate the sensors in the outboard sections of the wing, to
> keep them away from the prop's stream and engine influence.
> Again, there are double CDI ignition systems, transponder.
> 
> How does bluetooth work in this environment? What is the effect of
> other people walking around the plane with bluetooth enabled devices
> while in the ground?  Probably it can be made to work reliably, but I
> read enough stories of people having trouble using their bluetooth
> phones with their bluetooth car stereos.
> I'd rather avoid the extra R&D effort and stay with CAN.
> 
> >Keep us posted !
> 
> Will set up a web page when I have something to show.
> 
> .....
>
> The Xpresso board can be split into the processor proper half and a 
> debugging / JTAG programming half. 
> It is inexpensive enough and small enough that I doubt I'll design my
> own boards.

Did they finally make an LPC11C14 Expresso (not just LPC1114) ??
I used an IAR LPC11C14 board for initial development with CAN.

> The only major ingredient missing is free time. I am working on
> getting the plane itself back in the air, steam gauges and all.
> 
> R.
>
> (1) Excluding a few weak links like the USB connector in the 
> tablet(s).

Seriously, that may be a VERY big weak link in this environment...

Dave Nadler wrote:
>Did they finally make an LPC11C14 Expresso (not just LPC1114) ??

The ones I bought have an LPC11C24.

>> (1) Excluding a few weak links like the USB connector in the 
>> tablet(s).
>Seriously, that may be a VERY big weak link in this environment...

Yes - The tablet should be at least partially isolated from the
instruments panel vibration (and mine shakes a lot.) (1)
Probably a light frame riding on rubber blocks. I may have a small
board plugged  directly to the tablet, or a USB cable. Either one
should be secured to the same frame for strain relieve, any cable
leaving should have enough slack to accommodate the vibrations.
Currently collecting napkins and envelope backs before any serious
design effort.
Another solution may be an infrared link. Don't recall if the Streak 7
has one...

R.

(1) Or not mounted in the panel at all. A column bolted to the floor?

--
Roberto Waltman

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Time to think again?

http://www.reconinstruments.com/products/snow-heads-up-display
https://www.youtube.com/watch?v=hlwZWsGmDSA
--
Roberto Waltman

[ Please reply to the group,
  return address is invalid ]

Time to think again?

http://www.reconinstruments.com/products/snow-heads-up-display
https://www.youtube.com/watch?v=hlwZWsGmDSA
--
Roberto Waltman

[ Please reply to the group,
  return address is invalid ]