After the group discussion, we had a preliminary distribution of work. My job was the preparation and purchase of materials.
Lights
First I tried a mobile phone light source as a light for the water ripple reflection and determined that a point light source was the best light for reflecting the ripples.
I then tried a larger yellow spherical light source and found that this light source, because of its particular construction and colour, reflected colourful light through the object on the wall.
I tried other light sources of different sizes, such as a circular torch, a long strip of light, and a small torch.
But none of the results obtained were as good as the mobile phone light source and the yellow spherical light source. I presume this is related to the intensity and size of the light source.
So, after a discussion with the rest of the team, I decided to go for a mobile phone light and a yellow sphere light. The final choice depends on the final result.
Water Tank
Considering the light transmission of the water tank, I preferred to use glass as the material of the water tank. But as can be seen in Figures 1 and 2, whether it is colourless or tinted glass, it is difficult to reflect the ripples of the water visibly on the wall as the glass is too thick and has a strong light reflection of its own. So I came up with the idea of a transparent PVC material.
First, I purchased 110mm*110mm*110mm pieces of clear PVC and then glued them together with a glue gun to form a square water tank. Through testing, I found that the transparent PVC material had a good weight and light transmission, which was very much in line with our project requirements.
However, in subsequent tests I found that the tank was too small, resulting in a small projection area on the wall and a noticeable black edge. I, therefore, intend to re-purchase the clear PVC.
Laser Paper
In comparing the projection of the PVC water tank with a mobile phone light source and a yellow spherical light source, we have tentatively decided on a mobile phone light source. In order to achieve the light reflection in our design concept, we wanted to use laser paper to achieve this effect. This means that the white light source is reflected through the laser paper, causing the light to reflect in different colours on the wall.
However, practical tests showed that the projection of light on the wall through the single laser paper was not obvious.
Transparent PVC SheetS with Pigments
As the projection of the single laser paper on the wall was not obvious, I tried cutting the laser paper and pasting it in the form of a collage on a transparent PVC sheet. But the projection was also mediocre.
Then I tried to colour the transparent PVC sheet with gouache paint so that the light would be projected on the wall through the coloured translucent PVC sheet. However, the projection was still not good.
Therefore, I am trying to find other ways to make the light appear colourful on the wall.
Drip Device
We were going to make our own drip device but I suggested that we could just buy medical drip props which would give us better control of the drip rate. As medical drip props are not sold in the UK, not even for plants. I, therefore, decided to purchase them from China and have them couriered to Edinburgh. As the time between purchase and receipt was greater than two weeks and returns were not possible, I opted to purchase two different drip props for plants.
Arduino
We expect the Arduino to control the start of the drip unit, the running of the unit and the projection of the projector.
