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1141  Using Arduino / Project Guidance / Re: Capturing jpeg from camera to sd card on: January 02, 2012, 09:27:30 am
Is there any hardware that can turn video into compressed serial data less than 9kB/sec?
How about a way to convert a USB webcam?  That's not going to work it's uncompressed.
How about a video camera module with serial output like the JPEG camera?
A chip to compress NTSC and output serial data?
1142  Using Arduino / Project Guidance / Re: Measure distance between 2 circuits on: January 02, 2012, 09:11:45 am
Any new ideas for 2012?
1143  Using Arduino / Project Guidance / Re: OSC & Arduino on: December 31, 2011, 10:38:43 am
This example worked wonderfully.
http://www.sparkfun.com/tutorials/152
Only Xbee on UNO.  I wouldn't know how to begin going the other direction, I would like to see what you can find to do it!
1144  Using Arduino / Project Guidance / Re: OSC & Arduino on: December 30, 2011, 12:14:46 pm
I can do it FROM TouchOSC on iPhone to Uno.  But not yet TO iPhone.
1145  Using Arduino / Project Guidance / Re: NEWB trying to work with Nano on: December 30, 2011, 10:55:09 am
Detecting the lean angle of a motorcycle is difficult, especially at higher speeds.  It requires an expensive gyro, not an accelerometer.  A few companies have spent millions of dollars trying to find a better solution.  It would be much easier if there were no vibration nor extreme changes in angle.  There is an alternative using GPS data.  Unfortunately it will not react nearly fast enough to keep a video camera stable or level.

I love motorcycles and video photography.  You're going to want image stabilization in post production anyway to reduce the vibration in the video.  As long as you're doing that, use a wide angle lens and set the parameters to keep the horizon level.  This will work great at angles up to 30 deg, as long as you're not racing.
1146  Using Arduino / Project Guidance / Re: Measure distance between 2 circuits on: December 30, 2011, 10:40:00 am
Unfortunately the frequency of the linkage clicks changes with RPM. 
Even if I tried to keep a constant speed it would vary way too much, of course. 

I like your idea it is so simple!  Maybe there is a way to measure the energy level of each individual click from the linkage.  It would be much easier to measure the total energy in a second.  I can assume the RPM is roughly constant from 1 second to the next. 

Distance = C / sqrt (sound energy level) ?

Do you think I might get 1 meter accuracy?
I believe it might work, out to 20m or more, if there was no other sounds.

1147  Using Arduino / Project Guidance / Re: Measure distance between 2 circuits on: December 29, 2011, 09:43:41 am
OK so I can make a repeating pulse with PWM() or a 555.  Which is more stable?  I understand what you said about missed readings.  And how to calibrate it for temperature and humidity.  One thing at a time, 3D comes later.  We have decided that it will be difficult to receive a click on the helicopter due to all the high frequency clicks already in the blade linkages 3" away.  I'm sending a repeating pattern of clicks from the helicopter?  What am I measuring, the time between them?  Please explain.  It may only change by 50us.  This way I can detect that it's coming or going.  But it will give me no indication of its current position/distance?  Assuming the angle is unchanging, can I get a rough idea of distance from the magnitude of the click?

Maybe I should use RF to trigger each click from the helicopter.  What type of receiver can I use that is light weight?
1148  Using Arduino / Project Guidance / Re: Distance sendor 14C01 on: December 28, 2011, 10:39:19 pm
Would this work for my project?  I can't make much sense of your datasheet.
http://arduino.cc/forum/index.php/topic,84792.0.html
1149  Using Arduino / Project Guidance / Re: Measure distance between 2 circuits on: December 28, 2011, 10:38:07 pm
Let's say 10hz clicks.  100hz?  Which is best?  How would this work?  Pseudocode please?  I'm not convinced.
Anyone else agree?
1150  Using Arduino / Project Guidance / Re: Capturing jpeg from camera to sd card on: December 28, 2011, 01:49:16 pm
XBee is about 4x that speed.  What hardware can we use to compress the video and send it serially to XBee?
Small in size?  Low power?
Would be cool to see 10fps!
1151  Using Arduino / Project Guidance / Re: RTC + Arduino clock + scheduler on: December 28, 2011, 01:43:08 pm
My DS1307 drifts a few seconds per day.  So if you require 1 second accuracy, sync with PC every hour.  Do the math.
How do you correct your PC clock?  By default mine seems to sync with time.windows.com once a week.  I have Windows Vista.
I don't see how to change this period.  It is off by more than 1 second. 
1152  Using Arduino / Project Guidance / Re: Capturing jpeg from camera to sd card on: December 28, 2011, 01:15:21 pm
It CAN be done with XBee instead of an SD card.  The SD card is even easier, with a few lines of code.  It takes a few seconds to send a compressed 640x480 image at 9KB/s.  These results can be achieved with an Arduino and ZERO coding.  The hardware comes with a PC application that displays the image.  Just connect the modules and go.  The Uno is acting as a power supply with no sketch running.  The JPG camera talks directly to XBee.  This proves the concept is possible.  Then you can write the code to customize it for your application.

Frame rate?  That's for video.  1 "fps" is plenty fast for still images.  Low expectations?  We expect to see an image.  Yes it's 640x480.  Our expectations of the quality are realistic.  It's amazing to see whats happening 300m away without wires.  It can also detect motion or visual changes.  It's amazingly simple code if there is no movement normally.  It can ignore some leaves blowing in the distance as well as changing shadows due to the suns movement.  In fact it's only 1 line in my sketch!
1153  Using Arduino / Project Guidance / Re: Measure distance between 2 circuits on: December 28, 2011, 01:05:31 pm
It will probably not be reliable because the helicopter makes a lot of noise.  The plane does not.  This interference is why I suggested sending only from the craft using a clock to do it at a defined interval.  It is not so loud at 2m away.  I like the idea of a radio link!  What circuit can I use?  My first thought is XBee, but there is a variable delay in receiving a single byte.  It has to be low mass.  

@goforsmoke
I was thinking of making only 1 short click every 1 second.  Possibly 0.1 second.  You seem to have a different idea.  Please explain.  The distance wouldn't change much at 100hz, from one cycle to the next.  I assume we're talking 1-way transmission now, without a clock?
1154  Using Arduino / Project Guidance / Re: Measure distance between 2 circuits on: December 28, 2011, 12:55:23 am
@Magician - Great idea!  Where have a I heard that?  smiley-wink

You're correct, the timing between pulses will always be 1s for a slow moving object in my example.  But it will be shifted compared to the clocks by 30ms at 10m, at the receiver.  All I have to do is keep the clocks in sync.  Or measure how they drift consistently without any movement/distance.
1155  Using Arduino / Project Guidance / Re: Measure distance between 2 circuits on: December 28, 2011, 12:37:58 am
It will be easy to guess the temperature to get within 1-2%.  34cm/10m is about 3%.  34/5m is 6%.  Mostly I want to know if it's moving further away or closer to keep it at a constant distance.

What is the advantage of optical compared to 2-way sound?  The disadvantage is that light is much harder to point in the right direction from a moving rotating object.
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