# Engineering

## Robotic arm

In the last two years or so, I started learning about 3D printing and coding various microcontrollers. The ultimate purpose is to bring these into STEM education and promote maker culture in schools. Last year in 2019, I started a MakerClubQUT and began documenting various maker projects. End of 2019, I started building my first simple robotic arm and thought about the 3D rotations for the robotic arm to reach any particular location in space. I thought that I might try coding a virtual robotic arm in VRMath2, and here it is.

## Chaos game - square fractal

Chaos game is a mathematical way to generate fractals. It has a simple algorithm, which (1) starts from a radom point with a polygon, then (2) randomly selects a vertice, (3) plots a new point midway between the starting point and the selected vertice. The ploted mid point then becomes the step (1) and reiterates the steps as many times as you like to generate a geometric figure. The example below in this blog uses a square as the polygon to generate a chaos game square fractal.

## A pot of green

It is hot summer (in Australia), plants and grass are quite stressed with dry and heat condition. Some succullent plants can survive easier, and I happen to see a pot of Snake plant, and think that I can create a 3D version of it.

## ATCM 2017 Presentation

This is the presentation for my ATCM 2017 talk about:

Mathematics, Virtual Reality and Programming

## Flying boxes

In Web3D '17 Conference, James showed me how to do particle effect in Unity, which is very very cool. Then I thought that I may be able to create similar effect in my VRMath2 Editor. It turned out that it is quite easy to program in VRMath2, but of course the visual is not as good as in Unity. The simple codes, however, may be worth seeing, so here we go.

## Programming Driven 3D Modeling on the Web

This is my presentation in Web3D 2017 Conference on 5th June 2017. The presentation is about my paper titled "Programming Driven 3D Modeling on the Web", which can be downloaded from ACM Digital Library, or from the Publication section in this website. In this paper, I am introducing this VRMath2 application, which incorporates a programmatic approach to create online 3D models and virtual worlds. This programmatic approach of generating online 3D models is conducive to learning in science, technology, engineering, and mathematics (STEM).

Recently, there is discussion about pendulum wave effect produced using the Newton's cradle. There are many YouTube videos about pendulum waves. Having seen some of these "amazing" wave effect, I thought that VRMath2 Editor should be able to produce a fake, but good enough to show the effect of pendulum wave simulation. And here you go, see the 3D simulation below.

## Sea simulation

In junior high school maths, there are usually questions about measuring the angle of depression and/or distance using trigonometry. Common examples could be like "Find the angle of depression from a lighthouse beacon 112 m above the sea level to a boat that is at a horizontal distance of 1.5 km from the lighthouse". A picture (not to scale) may be given as the one on the right. But then, what if the scenario is in 3D?

## A boat with a sail

A classic boat has a main body (hull) and a mast with a main sail. Using the build-in primative objects, there could be some possible boats contructed. In this blog, I used three objects: a SNOUT for the hull, a CYLINDER for the mast, and a 2D PIE for the sail. Of course these objects are scaled and textured with materials and images to be looking like (I hope ) .

## Ethanol Molecule

Ethanol is a molecule containing a mere 9 atoms of which there are 3 different atoms and has been known to human long prior to the advent of modern chemistry.