photovoltaic cells

to start(btw, they're not PV--that's for power generation)

Look at some of the tracking technology employed by solar energy arrays - these huge concave mirrors sit on motorized platforms that allow them to spin throughout the day to track the sun. Also look at astronomy and telescope technology.

thanks rehiggins,

my thinking is that I would need a light sensor connected to an actuator that would move and allow the object to either fold or unfold, but i dont know what type of sensor and actuator or how to connect them etc.

there's always the passive tracker that uses a liquid in a closed loop. the liquid is heated by the sun, which causes the liquid to move in the loop, which changes the center of gravity, which causes the panel to tilt.
something like this.

much of what you're describing is basic robotics (light sensors, actuators, etc.)

my bet is that you need a stepper motor, a controller (this can be a PC), sensors to let the controller know where the armature is (though this can be done directly on the motor if using a stepper), light sensors…

Search for books on beginning robotics like this one: Robot Builder's Bonanza

Why not have the sensors also be a PV array. The mechanical system is going to have to draw power from somewhere to move unless your inventing a bio-synthetic type of object. When your batteries or inverters start to sense an increase in power generation that is when your kinematic object comes to life. i think that there could be a way to meld them both together and be somehow track the sun as it grows too.

the astronaut memorial by holt hinshaw pfau jones is a good precedent, although the tracking system failed a few years after it was built ..

You might want to check out Arduino, it'll do everything you need (I think), it's cheap and there's probably examples of code/setup somewhere online. I think you want an LDR (Light Dependant Resistor) to measure light, although a solar panel that powers the system sounds like interesting feedback.

these are great ideas, thanks everyone.

You should look at the automatic vent operators used in some greenhouses. They contain a paraffin wax cylinder which expands with heat. They are simple and cheap and you dont need any electronics. I always thought you could make a great project using these but never got a chance to try it.

Also, if you are interested in kinematic and origami type structures, you might be interested in this video of some of my student work:

http://spacesymmetrystructure.wordpress.com/2009/01/15/deployable-and-transformable-structures/

32Q2--

that's some interesting stuff on your blog--thanks for sharing!

do you have more info on how you created the folding/transforming shapes or was it pure experimentation?? some of it looks similar to Snelson's work. . .

very cool

Thanks rehiggins

The origami stuff developed through playing about combining some known corrugation techniques with various tiling patterns

http://spacesymmetrystructure.files.wordpress.com/2009/01/foldingpatterns.pdf

The process of trying to transfer these patterns from paper to material with thickness lead to all sorts of other explorations.

I looked at some interesting work on Bi-stable structures being done for use in satellites, and took apart a lot of tape-measures.

But my favourite stuff is the work with Bennett and Bricard linkages. Zhong You has invented some really cool ways of combining these. Most other work in deployables uses linkages which are essentially planar, even though they are arranged into 3D shapes, but these are fully 3D linkages.

and yes, Snelson was definitely an inspiration

32Q2
That video is really amazing, thanks for sharing. I've started to document crease patters, resulting form, and application. I also started a blog www.digigami.wordpress.com though i've only posted some documentation of digital tools.

The work of snelson, and the bennett and bricard linkages are interesting also.

HM