J
October 1st, 2001, 12:46 PM
I was just talking with an email contact about a computer controlled RC car he has built. One idea he had was to allow it to be controlled via the net. The disadvantage of this method is that a computer would have to be placed so as to be withing range of the RC system. Either that, or the vehicle would have to have a phone, modem and a computer of some kind on board, + a hefty battery pack.
My idea would dispense with everything but the cell phone and a small command interpreter. To control the vehicle, frequencies would be sent down the line, which would be translated into actions by the interpretter.
The circuitry would be simple (maybe even just a frequency controlled amplifier IC, a summing amp, and some logic), and the bandwidth of the phoneline is high enough to have many channels. This is another advantage; commercial RC systems of more than 2 channels are expensive (especially those over 4).
The video camera could be mounted on directional stand, which could be adjusted by the user over the phone. Wireless video cams can be bought off-the-shelf, although they are usually low range.
The range could probably be improved by adding on an RF amp (possibly disabling the one already on board first). This might attract unwanted attention though.
The basic (minus video receiver) control system could be smaller than a standard RF transmitter. It could have a built in cell-phone, and/or have the ability to attach to a standard phone handset. It would simply generate the correct frequencies according to the commands of the user.
The video receiving equipment could be a small monitor (maybe LCD) with the video receiver attached. Although not feasible now (AFAIK), in the future one of the next generation mobile phone's could be used. The standard phone on the vehicle could be replaced with a video capable phone, which would also receive the regular commands. Another phone could be built into the controller to receive the video!
This will probably be another project that I never get off the ground, but I thought I'd share the idea anyway. One obvious disadvantage is the cost of the phone calls.
Another advantage is the simplicity of the control unit. It would be easy to improvise in the field (minus the video receiving part) if the command syntax was carefully thought out. By command syntax, I'm thinking of whether a continuous frequency would be transmitted (the command is carried out while the frequency is present), or a start and stop frequency pulse.
I'd appreciate any suggestions or comments.
J
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My idea would dispense with everything but the cell phone and a small command interpreter. To control the vehicle, frequencies would be sent down the line, which would be translated into actions by the interpretter.
The circuitry would be simple (maybe even just a frequency controlled amplifier IC, a summing amp, and some logic), and the bandwidth of the phoneline is high enough to have many channels. This is another advantage; commercial RC systems of more than 2 channels are expensive (especially those over 4).
The video camera could be mounted on directional stand, which could be adjusted by the user over the phone. Wireless video cams can be bought off-the-shelf, although they are usually low range.
The range could probably be improved by adding on an RF amp (possibly disabling the one already on board first). This might attract unwanted attention though.
The basic (minus video receiver) control system could be smaller than a standard RF transmitter. It could have a built in cell-phone, and/or have the ability to attach to a standard phone handset. It would simply generate the correct frequencies according to the commands of the user.
The video receiving equipment could be a small monitor (maybe LCD) with the video receiver attached. Although not feasible now (AFAIK), in the future one of the next generation mobile phone's could be used. The standard phone on the vehicle could be replaced with a video capable phone, which would also receive the regular commands. Another phone could be built into the controller to receive the video!
This will probably be another project that I never get off the ground, but I thought I'd share the idea anyway. One obvious disadvantage is the cost of the phone calls.
Another advantage is the simplicity of the control unit. It would be easy to improvise in the field (minus the video receiving part) if the command syntax was carefully thought out. By command syntax, I'm thinking of whether a continuous frequency would be transmitted (the command is carried out while the frequency is present), or a start and stop frequency pulse.
I'd appreciate any suggestions or comments.
J
------------------
Download the forum archive (http://forumarchive.tripod.com)
PGP key available here (http://pgpkeys.mit.edu/) (ID = 0x5B66A792)