I
You can set up on a crowded street or beach,
turn on the Shutter Control, and walk away until
the memory is full or the batteries die. (Chain the
camera to a parking meter or lifeguard stand so it
isn’t stolen.) Later, dump your shots into a photo
editor, and I can almost guarantee that you’ll get
some with serendipitous timing and framing, like
my lucky shot of a lighthouse beam (Figure E).
The shutter button is pressed by a cam (Figure F)
that’s driven by a DC gearmotor. I used a band saw
to cut
1"-thick acrylic into a shallow spiral cam
about 1" across with a
1" drop. The drop should
slightly exceed the throw of your shutter button, so
that the shutter is pressed gradually and releases
fully. For the flattened hole that fits the gearmotor
axle, I drilled undersize and filed the hole to shape.
A simple circuit uses a 556 timer chip to run
the motor continuously or in pulses, with 2 potentiometers adjusting the pulse length and frequency.
If you’re using a low voltage to save battery weight,
pulsing the motor provides enough torque to press
the button when continuous power might not.
Slow speeds and mechanical triggering also let
point-and-shoots focus normally before each shot.
Occasionally the cam will press the shutter while
the camera is still “digesting” the last shot, but this
has done no harm to any cameras I’ve tried.
Figure G shows a schematic of the circuit, which
I often just leave on a prototyping board (Figure H).
Substitute different capacitor and resistor values to
change the possible pulse and delay interval ranges.
WINAMP MATERIALS
Computer running Winamp (
winamp.com) music/
media player
USB (or PS/2) keyboard Make sure it works with
the Winamp computer and doesn’t conflict with
its normal keyboard.
Micro switches such as momentary-on SPST
buttons or SPDT lever changeover switches
with the metal levers removed ( 8 or 9); item
#275-016 or #275-002 from RadioShack
(
radioshack.com)
Insulated wire 22- to 24-gauge telephone wire
works great
Small piece of stiff plastic laminate aka Formica
a bit larger than the PCB inside the keyboard
Small box to hold keyboard’s PCB. I made one out
of wood.
Heavy paper and laminating sheets
Small wooden dowel
Fine-tipped soldering iron and solder
Glue gun and hot glue
Mounting the gearmotor so the cam sits the
right distance directly above the shutter button will
require some tweaking.
I made a bracket out of ¾"×
1" aluminum that
attaches at the tripod mounting-screw hole in the
bottom of the camera. It bends up and over to
hold the gearmotor, which is attached through its
mounting holes. The aluminum is strong enough
to minimize play, but flexible enough that it springs
back a little when the shutter button bottoms out.
3 Winamp Joystick I love Winamp, but I don’t like having to use a
mouse or hotkeys with it. When I’m multitasking, it
bugs me to have to Alt-Tab over, then click around
or remember that X is Play and V is Stop.
So I built a joystick (more of a “joywheel,” actually;
Figure I) that emulates 8 of what I consider to be
Winamp’s most important functions: Play (hotkey:
X), Stop (V), Jump to File (J), Pause (C), Previous
Track (Z), Next Track (B), Volume Up (↑), and Volume
Down (↓). To this list, you might want to add a ninth
switch in the middle to emulate the Enter or Esc key.
Most control functions require a single satisfying
push on the big, bright wheel, and if I want to hear a
particular tune, I simply hit Jump, type a few letters
unique to the song title, and hit Enter.
The arrangement worked so well that I converted
an old IBM ThinkPad into a dedicated music player.
(Note: Laptop or desktop computers work equally
well for this project; I tend to lean toward portability.)
65 Make:
