Create & Improve 

During this phase, we started putting our plan into action. First, we created a prototype of our catapult. By doing this, we can visualize our product and find errors inside our design that we can improve on. We assembled our prototype together by taping popsicle sticks together and using a triangular wood block as the base. We adjusted our design from the plan by replacing the basket with a cylindric shaped basket glued onto a wooden platform. We assembled our pieces together and created a prototype.  

Our prototype: 

We created the prototype to find errors or ways we can improve our design. The strengths of our prototype were that the basket functions well and the length and width of the platform was ideal. After prototyping, we realized the platform on the catapult was not stable enough. We will improve this by adding more popsicle sticks on the back to improve the stability. We also realized that a triangular base is not optimal for this design since the incline of the slope was at the wrong angle. For our next design, we should account for the angle of the slope by stating it in our plan. 

After analyzing our own prototype, we sought feedback from some of our classmates to find areas we could improve on. After our classmates tested our prototype, we received some feedback we can iterate our design on. Some users said that we can improve our design by making it more visually appealing and more convenient. A problem that our users faced was when the catapult had to be manually reassembled every time it was launched. We decided that we will use rubber bands to connect the platform on our next design so that our platform does not have to be reassembled manually every time it launches.  

After analyzing what we could improve on our final product, we started reconstructing our plan so that it meets our new requirements. We reconstructed our plan by making new measurements and adjustments while adding new pieces to our design. We did this so we would have a clear and concise plan to follow while creating our final catapult.

Our new success criteria: 
-Able to launch/fire a small ball 
-Teaches students about energy transformation 
-Clearly shows mechanical, potential, and kinetic energy 
-Students can have fun playing with the toy
 -Safe to use and appropriate for classroom environments 
-Uses a syringe lever
-The base and platform are stable
-Inclined slope on the triangular base at an accurate angle
-The platform stays connected after each launch
-Neat/uses different colored popsicle sticks/ 

Our new plan: 

On our new plan, we recorded more specific measurements for each of our sides. We clarified the angle and slope of the base. We broke our design into separate parts to show each part more clearly. Our design included the new improvements we added according to the feedback we received from our peers and our new success criteria. We included the new rubber bands that would tie the platform to the base, so it stays connected after each launch. We applied different colored popsicle sticks for decoration. We stabilized the design and reinforced the platform with an extra layer of popsicle sticks while adding a square base to hold the syringe upright. With all our adjustments, the plan states our design according to the success criteria and feedback while guiding us through the creating process with precise measurements.  

After recreating our plan, we followed the plan and started constructing our final catapult.  

 

 

We constructed the base of our platform by taping 2 platforms 4 popsicle sticks together. Next, we added 3 popsicle sticks on top and another 4 popsicle sticks on the bottom to reinforce the stability. We used different colored popsicle sticks to increase the visual appeal. 

 

 

 

Next, we got a piece of wood and cut it to the shape and angle that we need according to our plan. We cut it according to our measured angle and length on our plan to form a triangular base. 

After completing our base, we connected 2 bars made using popsicle sticks to create a holder for the syringe lever.  

Then we connected the syringe lever to the platform by hot gluing the syringe to the platform. We also added a wooden board on the platform to hold projectile that would be launched. 

We attached a popsicle stick at the bottom of the platform. Then we glued 2 circular handles on both sides of the base. Finally, we connected the popsicle stick to the 2 circular handles with 2 rubber bands. This fixes the problem so that the catapult does not have to be manually reassembled. The rubber bands connect the base to the platform so that it stays connected after each launch. 

We finished the catapult at the end by adding a cylindric holder that would hold the projectile and stabilized the syringe lever by connecting it to the holder. 

Finished Final Product 

We tested our final product and it functioned properly. It was able to launch a small projectile while demonstrating kinetic, potential, and mechanical energy. Mechanical energy was shown when the syringe was pressed down while potential energy was demonstrated when the projectile was lifted by the catapult. Finally kinetic energy was shown when the projectile was launched and fell. Overall, our product worked as intended while being improved according to our new success criteria.