jbn@glacier.STANFORD.EDU (John B. Nagle) (05/12/88)
I'd like to hear about experience with various cameras and radio links
used with mobile robots. I'm interested in units suitable for a small,
high-speed vehicle in which the vision processing is offboard.
The ideal device, as pointed out by Russell Anderson in "A Robot
Ping-Pong Player", is a CCD frame-transfer image sensor, since with such
devices the entire frame is acquired as a unit and no artifacts of the
scanning process appear in the image. Examples of such parts are the
Sanyo LC99xx series. (The Fisher-Price Toy Camcorder and Lionel
Loco-Vision use the LC9943, a low-resolution part from this line.
There are higher resolution parts in the same family.)
Is a minature TV camera using such a sensor with at least 250x250 resolution
available yet?
Next best is a CCD line-transfer image sensor. The better Pulnix
units have these, and many robotic groups use them. What is the experience
with these?
The Sony Watchcam is a low-cost alternative. Any experience here?
What about TV transmitters and receivers? I've seen a few TV Genie
units around, but not only are they weak, they're illegal. But they do
sbow that such a transmitter need not be large, and there are bands in
which one can obtain appropriate licences. I do need something
about that size, though, say 4x2x2 or smaller. Is there such a thing
as FM TV gear, to improve the noise immunity?
Has anyone dealt with the problem of camera stabilization and vibration
isolation in a moving vehicle? The Steadicam gyro approach seems overkill.
Sorbothane shock mounting is easy enough to do, but is it enough to get
clear single frames? Has anyone tried using data from accelerometers
and rate gyros to stabilize an image electronically?
Has anyone tried sending data back from a robot in the audio carrier
of a TV signal or in the vertical retrace interval? If so, with what hardware?
Yes, I know it's a hard, ugly problem.
John Nagle