The final step in the interactive process is to generate perceivable events based on the information gathered by the sensory devices. Presentation Devices perform this function by creating sonic, aural, tactile or olfactory events. To make our list, these devices needed to meet one other stipulation, namely, that they can be externally controlled by a computer. (Of course, what can't be interfaced to a computer?)
Several manufacturers make computer controllable laser disc players, most of which receive commands via an RS-232 serial interface. LaserDiscs are useful not only because they provide very high quality playback of video images, but because they offer random access to any image on the disk. You can start playback at frame 1000, and then jump over to frame 54343 and start playing from there. More expensive models add beautiful fast-motion, slow-motion and freeze-frame capabilities.
You can get your own images pressed on a custom LaserDisc for about $300 per 26 minute disc. A bit pricey, but definitely the highest quality source of interactive video control.
For those handy with a soldering iron, there are lots of kits for making your own radio and video transmitters. Here in the States, this is legal as long as you do not exceed certain power limitations. Our European friends may know more about laws concerning low-power broadcasting in other countries. In most cases these transmitters are small, so they can be easily worn by a performer. Uses include transmitting video from the point of view of a performer, or broadcasting your music (as we did recently) to cars stalled in traffic. For kits try JDR Microdevices. You can also find some a wide selection of tiny cameras, transmitters, and the like in the SuperCircuits (Voice +1.512.560.0333, Fax +1.512.260.0444) catalog.
There is an extremely wide range of MIDI controllable synthesizers and samplers available. There are two basic flavors of sound generating devices: synthesizers, which create sound "from scratch" using various synthesis algorithms, and samplers, which create sound by manipulating a digital recording of a real sound.
Because of the constant stream of new models, many of useful devices can be purchased used. For the same reason, it is difficult to list all of the interesting units here, but there are some resources to help you find out more.
There is a library of synthesizer inforamtion at Sonic State's SynthSite. You can find short user reviews and extensive technical details for many, many synths. For a huge list of links to synthesizer and MIDI related sites, try the Synth Zone.
Direct tactile feedback is an area that is being researched extensively by companies interested in Virtual Reality. Devices that produce such feedback are not yet readily available. (Though at this point we recall the story of the Futurists, who in the early part of this century, wired the seats of a theater with buzzers that could be activated with a switch backstage...) Once this technology is widely (and inexpensively) available artists will of course appropriate it to their uses.
We have placed the area of robotically controlled objects items that move in physical space or have a phyical presence in this area. If you are interested in creating robots, it is quite possible to find an interested party to collaborate with you, as there are enthusiasts worldwide.
If you are robotics information, a great place to start is the Robotics Internet Resources Page hosted by the University of Massachusettes. There is a very complete listing of links, including a listing of clubs and cooperatives where you may be able to find comardes for collaboration.
The least expensive method of getting something moving is by using stepper motors. These motors, together with an "amplifier" board, require two signals to cause them to move. The first accepts pulses that cause the shaft of the motor to a small, specific amount, like 1.8 degrees. The second tells the motor if it should rotate clockwise or counterclockwise. As you can see, this system does readily connect to the serial output of your computer or your MIDI keyboard . Usually you need some kind of intelligent controller inbetween the computer and the amplifier board.
So far I cannot say that I have yet seen a computer-controlled device that can generate or synthesize smells. We did witness the work of artist and soon to be professional chef Margaret Hennesey when she created a splendid aroma based work, but sadly there was no computer interface to her Crock Pot. Perhaps you have a suggestion of devices that belong in this area...
Sensors | Interactive Languages | Presentation Devices | Roll Your Own
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