On screen display

[typicalaimster]

I picked up an on screen display from Intuitive Circuits (http://www.icircuits.com/prod_osdgpsid.html). I figured I'd give it a test run and see how well it worked. I was surprised how BIG it was. You can get the same thing on u-nav.com for $150.

http://www.myuav.com/gallery/main.php/d/177-1/Picture.jpg

Now I just need to figure out how I want to power it!

--Scott F

[kd7ost]

I use one of those Scott. It's a nice unit and works incredibly well. But you build those sweet, small, svelte planes and this would be big for your miniature UAS platforms. It would be very cool to have a smaller one. I also wish like hell someone would make one that the altitude reads out in feet. Mine fit's well in the gassers but it all adds up as weight. I use three LiIon cells configured in series for the voltage. It powers my Camera, overlay, microphone and transmitter. We need to come up with a thimbal sized breeder reactor. ;-)

Dan

[typicalaimster]

I use one of those Scott. It's a nice unit and works incredibly well. But you build those sweet, small, svelte planes and this would be big for your miniature UAS platforms.

Well I can probably cram it in one of my wing bays. At 1oz it shouldn't be a worry. I'm just trying to figure out where I'm going to get all this power from all of a sudden. Time to push the limits of my main cell!

--Scott F

[chrisgood]

If you want to build a small unit yourself to do this, here is what you will need:

From Decade Engineering, buy a BOB-III video overlay board.
From Parallax, buy a Basic Stamp II.

This code, available on the Decade website, it a simple program to read in the NMEA serial stream from a GPS receiver and send the data to the BOB-III for video overlay. The code was written for the BOB-II, but the BOB-III is backwards compatible:

--------

'Decade Engineering makes no warranty of any kind with respect
' to the usefulness or correctness of the information supplied
' herein. The user must accept all associated risks.
'
'This file by Michael McCarty, KB8YHV, kb8yhv@amsat.org
'
'The following Pbasic code is for the Parallax Basic Stamp II.
'This file may renamed to anyname.bs2 and used directly with
'the BSII programming software. All text after the ' will be
'ignored when programming the BSII.
'
'The following code allows the BSII to receive NMEA formatted
'serial data from a GPS receiver and write the data as text
'overlay on any video source using the BOB-II board from Decade
'Engineering. My video source is to be a mobile ATV setup in my
'car. ATV is amateur television transmitted by licensed amateur
'radio operators.
'
'The data input was taken as individual strings of text. I tried
'to have the BSII save the numeric strings as single bytes to save
'on variable space. The BSII only has 26 bytes available for
'variables, but there is a tremendous amount of data that can be
'received from a GPS receiver. The conversion from text to a decimal
'equivalent took too much processor time and it ended up missing
'input data. My GPS receiver sends a string every second so for
'the on screen clock to run smoothly with an update every second
'I had to catch all the variables with one command line. The only
'way I found to do it without missing data was to take it as raw
'text with no conversions. I was able to define the data I wanted
'(time, latitude, longitude, and which hemisphere for each) in
'22 bytes.
'
'id: clears the screen, pauses 100ms (required by BOBII after screen
'clear) and writes my call to upper left of screen
'
'get_data: receives serial data on pin 7 at 4800baud 8N1 (NMEA
'standard for GPS receivers), 2000ms timeout takes it to no_data
'subroutine, otherwise it waits for GPRMC (beginning of NMEA
'sentence) and begins parsing data. Time is then written to upper
'right of screen and receiver status is checked
'
'bad_fix: sends serial data to BOBII on pin 1 at 9600 baud 8N1
'which writes all position data to lower screen and flashes
'"last fix" to indicate old data
'
'good_fix: sends serial data to BOBII on pin 1 at 9600 baud 8N1
'which writes all position data to lower screen and writes
'"good fix" to indicate the receiver is currently tracking
'
'no_data: if input isn't recieved after 2000ms this sub is called
'which sends data to BOBII to overwrite all position data and
'flash "no serial data" at bottom of screen

time var byte(6)
latA var byte(4)
latB var byte(2)
lonA var byte(5)
lonB var byte(2)
lat_hemi var byte
lon_hemi var byte
status var byte

id:
serout 1,85, ["{A"]
pause 100
serout 1,85, ["{C0000KB8YHV"]

get_data:
serin 7,16572,2000,no_data,[wait("GPRMC,"),str time\6,skip 1,status,skip 1,str latA\4,skip 1,str latB\2,skip 3,lat_hemi,skip 1,str lonA\5,skip 1,str lonB\2,skip 3,lon_hemi]
serout 1,85, ["{C1600", time(0),time(1), ":",time(2),time(3), ":",time(4),time(5), " UTC"]
if status="A"then good_fix
if status="V"then bad_fix
goto get_data

bad_fix:
serout 1,85, ["{C0009LAT ", latA(0),latA(1)," ",latA(2),latA(3),".",latB(0),latB(1)," ",lat_hemi," {GELAST FIX{GDLON ",lonA(0),lonA(1),lonA(3)," ",lonA(4),lonA(5),".",lonB(0),lonB(1)," ",lon_hemi," "]
goto get_data

good_fix:
serout 1,85, ["{C0009LAT ", latA(0),latA(1)," ",latA(2),latA(3),".",latB(0),latB(1)," ",lat_hemi," GOOD FIXLON ",lonA(0),lonA(1),lonA(3)," ",lonA(4),lonA(5),".",lonB(0),lonB(1)," ",lon_hemi," "]
goto get_data

no_data:
serout 1,85,["{GE{C0009 NO SERIAL DATA{GD"]
goto get_data

[kd7ost]

Thanks Chris. All I see here is Time, Location (Lat and Lon) and call sign. Are there any PBasic Guru's floating around out there? It would be nice for me to get rid of time, and add altitude converted to feet as well as current heading. I'm not real strong with PBasic. I can parse the GPS strings though. Any takers?

Dan

[Gary Warner]

Last week I got my hands on a BA7046F. It's an ultra simple, 8 pin SOC IC that strips H and V sync from video. I plan on using it to integrate OSD (On Screen Display) of various sensors and data. I'll be using a PIC for the character timing and character library. And it will be coded in PBP (Pic Basic Pro). Maybe when I get the project going I can work on UAV OSD projects. For now though, it will be used to show accelerometer and servo position data.

[kd7ost]

Sounds good Gary,

We would be interested in hearing about the results as you move along with the project.

Dan

[Mr.RC-CAM]

I've been wanting a high end A/P camera controller with OSD Telemetry for some time now. Using Intuitive or BOB type OSD boards was considered. But in the end I decided to roll my own. I hope to be in the air by Sept.

The project is coming along nicely and is looking like it will be a handy gadget. Total weight of the board, with the integrated GPS module, is under 2 ozs. More details can be seen here: http://www.rc-cam.com/forum/index.php?showtopic=757

RC-CAM