This is my Create and Improve Blog Post created for the Science project: Grade 9 Energy Transfer Engineering. In this post, I will explain how I created my prototype, my thoughts on design optimisation, and analysation and application of peer feedback.
Creating the Prototype
The prototype I created included the body of the car, followed by the wheels, the pulley system, and finally the soldered wires connecting the battery to the switch to the DC motor. To begin this process, Ms Amanda was able to cut my LightBurn-designed cardboard pieces out using the laser cutter. (photo below) After this, I hot glued the pieces together, making sure that I had each piece on a 90-degree angle, and the two holes in the box were lined up.
Next, I glued on the straws for the wheels, and cut out a hole to attach the pulley system. Here I encountered my first problem of the pulley having too wide of a diameter, and I solved this by using a box cutter to cut more of the cardboard out, allowing the pulley to fit and turn with ease.
Afterwards, I attached the skewers to the straws and added the pulley and rubber band on top before using hot glue to put it all into place. My second problem was encountered when I saw the pulley hanging out of the bottom of the car base. This was solved by increasing the wheel size, which I glued onto the sides of the skewers, making sure they could spin and move easily.
The most difficult and important part of this process was soldering the electronic components of this car. This is the part that makes the car appeal to the energy-transfer part of the unit, converting the chemical energy to kinetic. After many attempts, Ms Amanda and I were able to make it so the batteries could be turned on using the flip switch and power the motor. We connected a smaller pulley to the DC motor and attached them to the car using hot glue and a popsicle stick.
After consultation with Ms Susan, Ms Amanda and I recognised that we needed to switch the battery that the electrical components needed. This led us to change the soldering the one seen on top of the final product:
What could be simplified? Improved?
One part of the process that could be improved is the time taken to create each part of the car. Personally, I feel as though the measurements of the straws and skewers could have been distinguished before the building process, so I could have been more time efficient and taken less time to get measurements more correct and neater. This was especially important when it came to the attached pulley on the skewer. It was slightly off-centre, making it difficult to attach the wheels to the skewer. In the future, I would attach the wheels first before gluing the pulley to the skewer, making the entire process easier. Furthermore, I would check how to properly solder the wires before attempting, as this took me and Ms Amanda almost 40 minutes on the first attempt to allow the motor to work, and this almost resulted in us blowing up a couple of batteries and frying many circuits. Fortunately, we got it to work the following day, however, this process could have been made simpler by doing more research during the define and inquire stages to insure minimal mistakes during the creating process.
OPTIMISE design
In order to optimise the design, I think there should first and foremost be fewer wires on top of the car, as it is unsafe for the user (a small child). Having too many wires can also be confusing and break easily as this car is designed to work outside.
Another point to be optimised is the material, changing it from cardboard to make it more enduring so it can be used on a variety of surfaces and remain durable through its use.
Furthermore, the battery could be moved inside the car or on one of the base’s sides to make it more aesthetically pleasing, giving it a cleaner look, and nicer for the target audience to purchase. This design could also be refined by having a more unified look. Whether that be painting the car’s base and wheels to match, I think that a product would benefit and be more eye-catching for the intended audience if the product looked more uniform and less “DIY” (despite this being more of a DIY assignment). A more prominent field of design is fixing the Lightburn files. My original files include teeth to easily connect pieces of the cardboard only on the top and lack them on the sides and bottom. In future iterations, I would like to change this by including teeth on every side to allow the car to be more easily and efficiently put together.
Finally, the straw used to hold skewers attached to the wheel could be shortened in order to reduce friction between the wheels and the straw. Since the straw and skewer length is very similar, the wheel is almost glued to the straw itself, making it very difficult to rotate, leaving the pulley system to go through more unnecessary work. By cutting the straw length shorter, I would be able to create a more efficient car.
What are the strengths of the prototype?
Some strengths of my prototype include its body, being solid and able to sit easily on a surface. Another strength would be the soldering, as it did work as a circuit. I’m quite proud of the soldering as it was such a big problem and took longer to figure out than the actual building of the car itself.
Peer feedback and application
Since I was unable to complete my project within the given four classes I was unable to apply this feedback to my prototype and create another iteration of my product. However, I was still able to receive feedback from my peers. This feedback included:
- Making the car able to properly function, could be done by cutting the straws at the bottom of the car as they’re not very necessary and create unneeded friction and resistance for the wheels. Additionally, I could shrink the rubber band to create less tension between the pulley system and the pulley wheels themself to the DC motor could rotate properly.
- Liked the idea of powering the wheels using a motor and then transmitting the power through a rubber band
- Enjoyed the use of environmentally friendly and reused materials
- Made the product user-friendly. As the product is made for children’s use, the large switch and product made it easy for small children to use and function.
- Liked how you made the car out of wooden boards, however, thought you could improve by using a lighter material to make it move faster and use energy more efficiently.
- Clean, aesthetically pleasing outlook
- Remove wires and battery on the outside
- Use a more recyclable/reusable base for the vehicle such as precious/recycled plastics
- Making the car move
- Liked the flamingo straw
- Liked the use of electricity in the energy conversion
- A solid concept of a battery-powered car
- The wheels should be more evenly spaced
- Attach the battery in a more secure fashion
In future iterations, I will make sure to take this feedback into account, especially feedback regarding making the car able to function (feedback no. 1), continuing the use of a motor and rubber band (feedback no. 2), using more environmentally-friendly materials to have a positive impact on the environment (feedback no. 3/8), making the product safe and user-friendly for children’s use (feedback no. 4), and using electricity in my energy conversions (feedback no. 11).