Above we see our mascot cum stooge Webio-Bot mesmerized by the slowly spinning a disk. And why not, even though what we have is just a series of circles going round and round, it looks more than simply that, eh? Does it look kinda alive, 3D and creepy to you? At any rate, this goes to show you can get seemingly complex motion from spinning one thing. And different motions at different speeds. All because of what they call persistence of vision. Which you might also call the wagon wheel effect. It all boils down to how we see motion as a series of still pictures running past rapidly in sequence. Rather than trying to explain what that entails, here’s a link. Less work for us.
We admit we didn’t invent this spinning disk thing. Artist Marcel Duchamp did it decades ago. In 1935 he published what he called “Rotoreliefs” illustrating the prinicple of rotary movement that would change with rpm. You can see some of them in action here:
Below are our imitations of Duchamp’s basic motif. Of course we use spirals. We just love spirals. Anyway, explore the differences at different speeds. The pips on the lines seem to move every which way depending on speed and how close to the center they are. They do to us, anyway.
mouseover buttons to change speed
Now Webio-Bot gets into the swim of things. Notice how the Aqua-Bot seems to bend into the flow the faster it swims. Or circles the drain, or whatever. At top speed it gets squashed into a bug-like thing. Maybe it’s our lying eyes fooling us, but it seems to swim in a tighter circle at the fastest speed, too.
mouseover buttons to change speed
Goofy? Maybe so. We’re having fun anyway. As the man said, or sang in fact, “You can’t please everyone so you got to please yourself.” Or it could have been, “…you’ve got to…” Hard to tell with singing. There’s a word for that, but we’ll save that for another day.
Now we forego the goofy distractions in the disc, no ovals, bots, bubbles and whatnot. Nothing but concentric circles all with exactly the same weight and style of dotted line. As you can see at “Stop.” So, even though every circle is rotating at the same rate, each has a different speed. The dashes of the outer circle cover a lot more ground per rotation than the inner circle dashes. They move progressively faster from the center circle outward. This is easily seen at the default speed.
mouseover buttons to change speed
The persistence of vision thing is not only a movie projection or computer monitor effect, it’s also how you see naturally. Your eyes scan quickly and repeatedly just like a camera. Here’s how you can show it to yourself. If you focus on the outer circle without moving your eyes you perceive a lot of short, blurry, purple dashes rotating slowly clockwise. If you follow the white dash around with your eyes you see what they really are: longer, more distinct dashes.
On the other hand, at the “Fastest” speed the green dashes just sit there and the yellow circle can be followed around with your eyes counter clockwise even though the disc is rotating clockwise like mad. Is that a result of the screen display or your own eyes? We don’t know. It is curious though, eh?
If there’s one thing the staff at terry colon point com likes better than spirals, it’s putting our stooge mascot, Webio-Bot, through the blender to become one indistinguishable bot swarm as he goes from stirred-not-shaken to frappé.
mouseover buttons to change speed
Notice how the outside bot seems to be bigger than the inside bot at “Fast” speed while the top bot is biggest of all. See how they bend at “Faster” speed. Watch the inner bot grow a tail at “Fastest” speed. Why? We can’t explain it. Maybe Webio-Bot is simply a freak. Then again, if you were spun that fast maybe something would come out of your rear end, too. “Holy Coriolis, Batman!”
Our last bit is just for the fun of it. If nightmares are your idea of fun.
mouseover buttons to change speed
In this one… virtigo! Or something. As the man said, “What you see is what you see.” That’s all she wrote. Pleasant dreams.
