Develop and Plan

Applying and reflecting on the pros and cons of Define and Inquire, I came up with two designed ideas based on the precedents researched. One is from the first steam engine, and another is from the potato clock (fruit battery). I skipped developing an idea of a second precedent, a solar panel light bulb since I believed it was way too simple and would not be able to put or show enough effort in the product.

An idea generated from “the first steam engine.”

This product essentially displays energy transfer in the first steam engine how it works.

In this mechanism, energy transfer starts from heat energy, turns to gravity potential energy, and ends with kinetic energy. In the process, due to heat and cooling water that is added repeatedly, the water turns to steam when heat is added, and it comes back to water when cooling water is added. Since steam has a considerably larger volume than water, the volume inside the tank repeats, increases, and decreases. Consequently, the piston moves vertically up and down.

By controlling the torch, users can decide whether to expand or contract inner volume. Thereby, users can directly observe how energy transfer works and where it is used.

On the other hand, it is nearly impossible to move considerably in the simplified and reduced structure. It might turn out not to show any operation, which is a complete failure. Besides, it is complicated to build the system.


An idea generated from the “potato clock.”

This idea is mainly originated from the potato clock. The only difference is the usage of electricity. Instead of actuating clock, it runs a carousel that tallies with the objective of this project, to make a device that can entertain children.

The product is designed as the image above, Two (or more if needed) fruits with zinc and copper strips plugged in are connected to a motor inside the base of the carousel. Then, using specially designed gear, a vertically spinning motor horizontally runs the part of a carousel where horses are attached. The gear is called bevel gear, which allows transmitting the direction of mechanical power happened between two shafts.

This device would mostly be made by 3D printing, as it demands high quality and accurate measures.


The decision between two options & the reason

My final selection for the project is a “fruit-powered carousel.”


The reasons for selection are:

-The model of the first steam engine seems to be so complicated that I cannot finish the project in 2 weeks. Fruit-powered carousel has a higher probability of success.

-Considering the objective of the project, fruit powered carousel better fits the purpose as it is a nice toy for young children and at the same time, educates straightforward about energy transfer. Whereas, the model of the first steam engine is too dangerous for young children to play with.


Planning/ Specifying the product

Materials: 3D printer & filament, 1 motor, 5 or more wires, two pieces of fruit (lemon is recommended), glue gun, two copper strips, and two zinc strips.

Techniques: 3D modeling, scientific knowledge about the reduction-oxidation reaction (redox reaction),  some knowledge about electronics.

+additional note: I found out that ISB does not have copper and zinc strips. There was nothing about zinc but for copper, instead of copper strips, copper tapes exist. Through brief research, I figured out that aluminum can play the same role as zinc in the redox reaction. So as an alternative, I am planning to work with taping copper tape and aluminum foil around the thin metal boards instead of copper and zinc strips (supervisor staff told me that it is the only kind of thin metal in Fab Lab).


Steps for creating the device
  1. Model the parts that need to be 3D printed. Send it to the 3D printing request site.
  2. Assemble the 3D printed parts.
  3. Stick horses on the roof and immobilize motor to pillar using a glue gun.
  4. Make lemon battery with copper strips, zinc strips, wires, and lemon.
  5. Connect lemon battery and motor.
DP_G9 Engineering Project

This is a link to a document file with all the images that are supposed to be in this document.

Due to the poor quality of the photos, I am attaching this file.