5bot sketch

July 6, 2005 on 10:13 pm | In Oribotics | No Comments

The 5 bot, so called because it has 5 petals, is shown here in a ‘rough’ 3D sketch. I have just started experimenting with using 3D software (this is my first 3D model) to visualise the new forms of the bots. The intention here is to design pieces which can be easily laser cut from clear acrylic, and joined by carefully placed bolts or glues. This form does not include the folded flower.

Being the first sketch, I have lots more refinements and designs features to add. As you can see, the model is very similar in design to the original bots. However, it is possible to scale this model in design, whereas LEGO (god bless it) can not be simply enlarged and recut.

What has disappeared from the design is the geared section of the bot, I hope to use higher torque DC motors, which would eliminate the need for the gearing (testing with suitable candidate motors still needs to be done with this).

Rigid Origami

June 20, 2005 on 11:15 pm | In Oribotics | No Comments

Tom Hull, a US based mathematician and origami researcher, has written a number of articles about the subject of Rigid Origami. Rigid origami is essentially a crease pattern in which:

(1) Paper does not stretch.
(2) The faces of the folded paper are flat (as opposed to curved).
(3) We do not want the paper to rip or have holes.
(4) Paper does not intersect itself.

See: http://www.merrimack.edu/~thull/rigid/rigid.html

If a crease pattern meets these criteria (its a bit more complex than this), but points 1 and 2, are essential in understanding a rigid fold.

The results of which are a crease pattern which is ideal for oribotics. Oribotics requires a crease pattern which can be set into motion with a mechanism. The first oribotic flowers are not rigid folds, however the amount which the crease pattern requires the faces to curve is small enough to allow the flower to open and close. But the springiness of the flower, is a result of the tension from the paper (or plastic) curving. If this were eliminated by altering the crease pattern the tension would be removed and the folding would require less energy.

Note that the first prototype oribot was based on a square twist fold crease pattern, however the twist was symmetrical, unlike this animation shown here: http://www.merrimack.edu/~thull/rigid/squaretwist.mov

« Previous Page

Entries and comments feeds. Valid XHTML and CSS. ^Top^