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innerbreed
07-19-2011, 05:57 PM
Well this project is exactly what it says it is...

This is a 6dof Stewart platform hexapod.
A Stewart platform is a type of parallel robot that incorporates six servos arranged in a prismatic layout.
The servos are mounted in pairs to the base, crossing over to three mounting points on a top (Target) plate.
Devices placed on the Target plate can be moved in the six degrees of freedom in which it is possible for a freely-suspended body to move.

http://i531.photobucket.com/albums/dd355/innerbreed/SAM_0414.jpg
http://i531.photobucket.com/albums/dd355/innerbreed/SAM_0416.jpg
http://i531.photobucket.com/albums/dd355/innerbreed/SAM_0413.jpg
http://i531.photobucket.com/albums/dd355/innerbreed/SAM_0417.jpg
These are the three linear movements x, y, z (lateral, longitudinal and vertical), and the three rotations pitch, roll, & yaw.

Now the interesting part.. :lol:


Does anyone have experience with a Stewart Platform, running on the Basic Atom Pro28?

anyway there it is, i hope its of interest?!

Slugman
07-19-2011, 06:53 PM
Sorry, no experience here, but looking from the outside, if each right hand servo in each pair moved up, & each left hand one moved down, would the target plate / head rotate clockwise? Looks like you can get limited rotation as well - Plus or minus 30-40 degrees or so depending on the ball joints. Chuck a dolls head on it & you could get some freaky animatronic head movment going! :happy:

Xevel
07-19-2011, 07:18 PM
It looks good, but as far as I know it's not exactly a Stewart platform.
These things are normally done using linear actuators. Using rotating actuators the way you do will have a direct impact on the kinematics of the system, and you won't be able to use equations from a canonical steward platform.
(And btw, I studiet Steward platforms at school, deriving their equations is not exactly funny...)

Do you want to control it using IK ?