Planar Motion Mechanism
 

Been looking for a cheap, easy to build with readily available parts and no specialist tools system for you know what

Motors, pulleys, rods etc obtained here >

http://www.mfacomodrills.com/pdfs/gbxbrch1.pdf



springs from here >

http://www.ondrives.com/products.asp?recnumber=313




last but not least is an mpeg1 movie showing the logical operation

please right click below for download - 30 meg per day limit!!

http://home.ripway.com/2004-7/146010/pmm/PMM.mpg

if anyone can host the mpeg - please do!

Thanks for the link. I noticed alot of useful parts like antiviberation mounts, mounted bearings and pulleys. Good find!

the key to success is not so much in the method of producing the 'deliberate motion' but rather achieving an acceptable level of vibration.

remember a 1 pixel vibration (=36/720 = 0.05mm) is like turning the custom sharpness down to the minimum on most cameras

a good test with any design would be to shoot a 1956 chart with the rig spinning to guage how much loss of resolution is present due to vibration - you can easily spend $100-300 on quality anti-vibration mounts

also my tests show that the amplitude of 'deliberate motion' should be at least 2mm (on a Nikon F3D GG) without seeing any grain up to F8.0 - even then the GG is smoothly grey and acts like a Neutral Density filter

John,
In my experience, I saw no need to create a motion bigger than 0.2 mm (the whole GG roating)
It seems to be enough to mix&blend all grain whithin itself.
I can not "see" it (providing there is enough light) stopping down to 16 on the SLR lens.
Speed should only follow this simple logic:
If one shoots 1/60, than all you need for every frame is one (or LESS!!!!) complete circle for every grain of the GG.
Tests got me to this result (not theory)
At this level of motion (and speed) all it takes is a very precise, eficient and small motion generator (which I have made)
The NOISE and VIBRATION LEVEL are to a MINIMUM due to small mass moving. Hence the low power needed to get it all in motion.
Are you still following this path ? (gg oscilating)

You can host the MPG at www.yousendit.com.