Canon SD450 Triggered by Sonar and the Arduino

This weekend I played with my Canon PowerShot SD450 (aka IXUS 55) and the CHDK along with the Arduino and the MaxBotix MaxSonar LV-EZ1.  The idea is to automatically take pictures when an object moves into frame.
Part of the job involved hacking a USB cable to hook up to the Arduino which I promptly did, as you can see below.


Unfortunately, I was supposed to hack a Mini-USB cable (of which I have a dozen) and instead hacked my (only) Micro-USB cable (oops).
The end I soldered two break away headers and then encased the whole thing with hot glue.

Here's the setup. You can see the sonar on the right.  I soldered a female header to it instead of soldering wires directly to the board.  The hacked USB cable is connected to ground and pin 13.  For the sonar I've plugged it into Ground, 5V, and pin 7.

You may also note that I'm not using the AN (analog) pin on the MaxSonar, but instead the PW (pulse width) pin, unlike most code I saw on the web.  The code is near the bottom on this arduino.cc page. My final code for the arduino is here.

I should mention that the CHDK is a little tricky to setup on the SD450 for shooting remotely by USB.  From what I understand it's supposed to be able to do that out of the box, but it didn't work for me.  However, by creating a LUA script for the camera I was able to get this to work.

To finish the project I'm going to glue that bolt you can see under the plastic container which just happens to be the right size for a tripod bolt.  I'll also add a potentiometer which I'll hook up to a threshold, how far the subject must be before I take a shot.  I'll probably try and take some pictures of hummingbirds near the feeder this weekend.

Comments

Post a Comment

Popular posts from this blog

Shortest Sudoku solver in Python

Mark Byer's site has some more Sudoku solvers here's a short one in Python that's only 178 bytes long: def r(a):i=a.find('0');~i or exit(a);[m in[(i-j)%9*(i/9^j/9)*(i/27^j/27|i%9/3^j%9/3)or a[j]for j in range(81)]or r(a[:i]+m+a[i+1:])for m in'%d'%5**18] from sys import*;r(argv[1]) On the site is also shown a longer Perl version at 185 bytes: use integer;sub R{for$i(grep!$A[$_],@x=0..80){%t=map{$_/27-$i/27|$_%9/3-$i%9/3&&amp;amp;amp;$_ /9-$i/9&&($_-$i)%9?0:$A[$_]=>1}@x;R($A[$i]=$_)for grep!$t{$_},1..9;return$A[$i]=0} die@A}@A=split//,<>;R I think the Python version is slightly easier to understand, although they are both quite cryptic. I'm not sure why I find these programs fascinating. I think it reminds me that any program can be written in such a way that it's cryptic, even in Python. In addition, the code is small enough that you should be able to figure out how it works, and may learn something the process. Related is
Read more

Seven Segment Display in Inkscape

Image
Today I got a little sidetracked while working on my key-train (keyboard training) project.  I thought I might spruce it up a little by using a seven segment display for the digits (say for the words per minutes), similar to what kTouch has.  I found an open source font, but it appears to be difficult to just use a ttf font in GTK. So I figured, it's only 10 images, I'll just make them in svg. I vaguely remembered a heathenx inkscape podcast  describing how to make an LCD display and decided to use that at my base. Unfortunately, they didn't provide any source files in the show-notes (as far as I could see) so I had to watch and redo the drawings myself! By naming each of the seven segments I could create the 10 digits simply by deleting a few elements in one template svg file .  I can create the template as beautiful as I like and quickly create the 10 derived images with these programs . Unfortunately, both ImageMagick and GraphicsMagick don't handle
Read more

Dot to Png

Image
For fun I wasted some time creating diagrams using the dot language. It's pretty fast to get a diagram out, except that there are a lot of things you can't do, like make shadows or rounded and filled rectangles. With this dot code: digraph "User Clicks" { node [ shape="rectangle" style="filled" ] server [label="Server"] java [shape="ellipse" label="Java\nCode"] provider [label="Service\nProvider"] browser [label="Firefox"] browser->server[label=<&#9312; AJAX Sends Session ID>]; server->java[label=<&#9313; Confirms Session ID>]; java->provider[label=<&#9314; Makes HTTPS call>]; provider->java[label=<&#9315; Results>]; java->server[label=<&#9316; Results>]; server->browser[label=<&#9317; Results>]; } You can click on the image to see the SVG rendered in Firefox, if you use that. I wrote a little python program to call t
Read more