Large Solenoid Actuator driven Display
October 27, 2009
Hello, I am new to this site so I hope you won’t mind if I ask a few questions that I am sure are going to sound quite amateurish to most of you.
I am an American living in Berlin working on a collaboration between two art research institutes here. I have been given the task of putting together a proposal for a dynamic moving display. That will be featured next year as part of a conference on kinesthesia.
My back ground is not in computing or robotics, I am simply putting together a list of materials (and their cost) that would be necessary to make this project work. And I am responsible for finding collaborators that can help put it together.
I found this website when I was researching solenoids. If you have any experience with solenoids I would greatly appreciate any advice or knowledge that you would care to pass on.
So let me try to explain what we would like to do and what I think I might have figured out so far – please be patient and bear with me.
The dynamic display I spoke of can be thought of as a much larger version of this pin-art-clock
However the display would not be used for numbers but instead for larger art-related images. Instead of metal pins the display would use much larger plastic knobs (for lack of a better word). The idea was to use individual actuators to individually lift up each of these knobs so that you could create a series of unique images , symbols, impression, etc. I hope this makes sense the way I am describing it. In theory it should be able to handle quick successive displays resulting in a seamless image concept. To get a better idea of what I mean take a look at the following youtube vid.
Each knob would have to be able to be raised and lowered independently of the others and in quick succession because the images would in effect be streaming across the display. The display would be quite large (2 to 3 meters in length and width) with several hundred knobs and corresponding actuators in order to achieve higher resolution. The knobs would be constructed out of light weight plastic.
I located these companies for solenoids:
I thought a small, electric - AC, linear, pull-type solenoid should suit the purpose. The only problem is that the shaft extension length on most of them is quite short. I was thinking that for best resolution it would be good to have a difference between the raised and lowered knobs/pixels of at least 2 to 4 cm. However, most of the solenoids that are capable of achieving that are far too powerful (and thus expensive) for our needs. I realize that it would be possible to devise a lever of sorts to amplify the small movement but that would result in more moving parts and thus a greater chance of breakdown and higher maintenance. I also looked at the possibility that I saw recommended of a camshaft with suspension spring but I think this would be too bulky to place side by side and would not possess sufficient speed.
And I thought that this microcontroller, or something like it, that I found on this forum might be what would be needed to independently control the solenoid actuators.
So what I would like to know is what kind of solenoid would you recommend for something like this (does not require large force, does require large shaft movement of 2 to 4cm)? How do I determine how long it can remain on (in a contracted position) and how long it has to rest (heat dissipate) before it can be activated again. Is is possible to get an electric solenoid that is able to be activated in quick succession (1 to several times per second) for several hours without damage? What would be the best means of control several hundred solenoid actuators independently? Would the microcontroller I posted above work, and if so would I need several of them to control a large number of solenoids or is one scalable – if I do need several is there a way to link them to create a seamless image? What should I take into account when deciding on an operation voltage? Finally what would you expect to pay for the type of solenoid that I described above? Also any suggestions on the best way to hook up a power supply would be appreciated.
I will definitely have more questions, but I thought this would be a good place to start. I hope you will be able to help – and patient enough to make it to the end of this long posting J