Kite Photography with the Raspberry Pi

Transcription

1 Kite Photography with the Raspberry Pi Zak (Photos, unless otherwise noted, are available on my flickr page, flickr.com/photos/japharl/ or personal collection)

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3 Introduction I like the idea of aerial platforms (rc drones taking photos, etc), partially inspired by the book eyes in the sky. Needed something safe & legal within the DC-SFRA (discussed later) Low altitude platforms provide a bird like perspective of near targets Challenging & fun

4 Note This is my personal attempt at doing this. There is a community that does this at: See also: for general information about kites.

5 CPU Hardware Raspberry Pi A+ (256 mb memory) ($20 ish) / Pi Zero Rev 2 ($5) Note - camera seems to connect easier to the A+ than Pi Zero. YMMV. Raspberry Pi Camera 5mb /7mb ($25 ish) Power pack ($15ish to $5ish) Sense hat ($30ish) SD Card ($10ish) TOTAL: $110ish

6 Kite hardware Rig - (variable cost) Screws & Bolts $30 ish from bolt depot for good variety (if needed). Kite - $40 Rope - $20 (150 lbs strength; 500 ft), buy new each year Large Gauge Bronze wire - $4 for (large amount) Nail Polish $2 Total ~ $129

7 Early Code Code: Essentially: crontab entry which is: raspistill -o cam.jpg

8 Platform 1 Cheap platform to attempt to see if idea is viable Unfortunately, weak physical connections resulted in platform becoming separated from kite, lost in ocean. Also no code backup :(

9 Platform 2 Made a custom acrylic laser cut platform. Learned how to do that (fun). Bought screws to securely attach to platform. Added if lost, please call sticker. ;) Wanted to update location of pi power location; camera cord length ; a few others

10 Worked!

11 Platform Rewrite code in python to use sensors and lights available on the raspberry pi sense platform. Make it so that it has more of an enclosure so nothing get damaged. a. till it crashed

12 Platform 4 Made out of card stock paper, pi zero, sense hat, and power. Worked well, except that the card stock paper tore need to come up with a solution...

13 Worked well, minus white balance

14 Wrote my first Python Code Detected that it s not shaking (to hopefully take better photos) Display the sense hat when it is taking photos Record the temperature, barometric pressure, and humidity

15 How Shake Detection Works Quickly call accelerometer sensor twice Shake = [(x1-x2)2 +(y1-y2)2 +(z1-z2)2] Gives a shake value between 0 & (very large number). The higher the shake (difference in either x or y or z axis, quickly), the more you don t want to take a photo. When this value is small, take a photo. Or, if shake > small value, decrement a counter starting at 1,000. If it gets to zero, take a photo anyway.

16 Also, height detection via barometric pressure log If you know the barometric pressure and temperature on the ground, and in the air, in a reasonably same time frame, you can calculate using (complicated math) the height difference, as the higher you go in the air, the less dense the air becomes. Source:

17 Version 5 Photos Samples are pending more cooperating weather Initial testing suggests this platform is more tolerant of crashes.

18 Recommend: A Delta Kite Advantages: A lot of lift, and therefore easier to fly, and get sensors aloft.. Disadvantages: Requires a firm structure. Therefore, not as easy to transport because it cannot collapse as easily. About $ You will be able to fly when you hear the wind in your ears as you walk.

19 Now, let s talk about the DC area & Safety Laws Booo

20 DCSFRA Plan to put in place before 9/11 as it was recognized that the DC area is special. Made permanent more recently (for area in red). Flying an unmanned aircraft within the 15-mile radius inner ring is prohibited without specific FAA authorization. Flying a UAS for recreational or non-recreational use between 15 and 30 miles from Washington, D.C. is allowed under these operating conditions: X Aircraft must weigh less than 55 lbs. (including any attachments such as a camera) X Aircraft must be registered and marked X Fly below 400 ft. X Fly within visual line-of-sight X Fly in clear weather conditions X Never fly near other aircraft Rules: Image :

21 HOWEVER, Kites are Bring your kite to the #CherryBlossomFestival April 2nd, 2016, 10:25AM Aside - kites were originally prohibited in the DCSFRA, but enough people in the general public protested to allow for kites, and sledding on the National Mall. See:

22 Practical Guidance Not legal advice (but my best guess) Obey no kite signs near DCA Airport, along Potomac River at Gravelly Point, or as posted. 500 max height. Check for any NOTAM s on FAA s website before you go. No night flying unless you have additional lights, or is visible via spotlight. Lights need to be visible 5 miles away (strobe), and regularly at ~ 100 intervals. See:

23 See also FAA s b4ufly app for UAV s. Gives you a good list of resources to check (NOTAM, Fixed Facility Listing, National Park Listing, TFR s, etc.)

24 Questions?