2.3 Design Rationale

We have decided to use Zi Heng's design.






As a group we concluded that the materials used for our car should be :

~Light-weight
We decided that the materials used for our car should be light weight , as more weight can affect the distance the car travels. If the car is too heavy , it will not travel far , therefore our materials must be light-weight

~Cheap
We decided that the materials used for our car should be cheap and affordable. This is because we were not given any budget and we do not really have much money. Thus , we decided to set a budget of $10 - $ 15

~Sturdy
We decided that the materials used for our car should be light-weight and sturdy as well. We noticed that certain materials are not suited for the design and would fall apart easily. Thus , sturdiness becomes a key factor for the materials we choose.


~Easily accessible

We decided that we will get common materials as we can easily get more of them if we run out of the materials.

Materials : 

We did much testing and modifications. In the process , we have also swapped materials for various parts of our car.


Our final prototype consists of :


Wheels which are made out of CDs. Our initial design called for using corrugated cardboard. However , we realised that corrugated cardboards often leaves tiny flaps on the sides after cutting , making it an uneven surface for the car's movement and travel. ( We will elaborate more on this in section 2.3) 


We eventually decided to find household items which were round and had smooth sides. As CDs met this 2 criteria and the 4 other criteria stated above , we decided to use CDs for our final prototype. 


Chassis which are made out of cardboard. Cardboard is strong and sturdy. It is also light weight and could support the weight of the mousetrap as well.Cardboard was also easily available in school we got them from recycling points and friends 


Our Lever is a wooden rod we found at home which was about 10cm. We secured it to the mousetrap using rubber bands . This is because of the design of the mousetrap which had to have lever that had to be engaged ( crossed over the mousetrap main arm). If we were to use tape , the lever could not cross over and the mousetrap would not engage. ( We will elaborate more on this in section 2.3) 


We chosen the plastic camping string we were told to bring for OBS. It is strong can does not wear and tear easily. 



The string which we have chosen.


Axles which are made out of wooden rods and satay sticks. We found these materials at home. We attached them to CDs which were our mouse trap car wheels. The satay sticks and wooden rods were easily cut and we could cut/modify them to suit our project's needs. 


Positioning of the mousetrap : We decided to position the mousetrap nearer to the head of the car so as to allow more space for our string which will be the "engine" of our car. 


Below is a picture of our car. 





No comments:

Post a Comment