Geometry | BrickEngineer: LEGO Design

I call this creation The Blossoming Lotus. It was originally posted on Online Cortex, but I have decided to repost it here because its just plain fun. Basically it is a large 2D version of a Hoberman sphere. Why did I not make a large Hoberman sphere? First, the parts to make the circle cost almost $80 US. Second, I have other more pressing projects I am working on.

The Blossoming Lotus Kinetic Art

It is about 4 feet in diameter when completely extended and is pretty impressive. Its relatively easy to make. My design consists of constructing each petal with two interlocking pieces: a single-claw arm and a double-claw arm. The parts needed to make the two arms are illustrated below.

Parts for a Single Lotus Petal

To make the entire circle of petals, one needs 20 copies of each petal. The job then is to put them all together. I will post detailed instructions on a website in the near future. For now, here is a closeup of the blossom when completed.

Close Up of the Lotus Blossom

And of course, the project wouldn’t be complete without that animation above made with MLCAD, L3PAO, and POV Ray. The animation was straightforward—once you get the geometry right (which is not straightforward). I will post a lesson on the geometry and the animation of this creation in the future as well. For now, enjoy.

LEGOs are designed to go together to form rectangles. Here I present some possibilities for equilateral triangles, which can be extended to form hexagons. Some of the more recent triangle designs, which I present below are being used in a current design for a tri-wheel drive system for a Mindstorms rover I am currently constructing.

These first triangular designs are equilateral triangles (same side lengths), and can be put together to form hexagons as well. These are extremely sturdy constructs and may find use in triangular or hexagonal bases.

Below is the smallest LEGO equilateral triangle. The parts used to construct it are shown to the right. It often takes a bit of pressure to snap this together since it is a tight fit, so take care when doing so.

One can make equilateral triangles of any size this way.

Big Triangle

If the connectors are a bit cluncky,
one can use the thin technic liftarms with the small axles to secure the triangle.

Alternate Triangle Design

Here is a rotating image of the result so you can get a good look.

Alternate Triangle Design

The two following designs are slightly alternate forms.
One uses beams of length 11, but is offset slightly so that there are empty peg holes at the corners of the equilateral triangle.

Alternate Triangle Design

The following design uses beams of length 9, and lacks holes at the triangle corners.

Alternate Triangle Design

The following triangle is composed of beams of length 11, and has a a 3-blade rotor in the center to act as an axle. The parts list and instructions can be found here.

Equilateral Triangle with Axle

An animated version illustrates how the braces hold the central rotor in place.

Equilateral Triangle with Axle

BrickEngineer: LEGO Design

LEGO Engineering for LEGO NXT and Robot Enthusiasts

Tag Archives: Geometry

The Blossoming Lotus: LEGO Kinetic Art

LEGO Triangles