Final Product

Cross-Bow-Dream Shooter

Rachel Cai and Angel Yin

Dream Shooter is a cross-bow toy demonstrating elastic to kinetic energy; the materials used for this product are all recyclable and contain protection to ensure the safety of the consumer.

A short video of our product and working process; please enjoy.

 

Here is a link in case the video doesn’t work

How does it works

Elastic energy stored in the limbs of the crossbow is transferred to the arrow upon release of its rubber band, the rubber band gives the arrow enough kinetic energy to move at a certain speed.

Reflection

Successful parts                                                                                                                                                    Our product did well in a clear demonstration of elastic to kinetic energy, the rubber band transfer strong energies to the straw and made our product playful. Also, our product is 80% the same as our original plan, and we create our product efficiently, which gives us enough time to improve and decorate.

Need improvement parts                                                                                                                                      One mistake and unconsidered occasion is the bottle lid stabler, which had impacted our final product. The original plan is to pinch two holes on the lid as a stabler for the arrow, this could increase the accuracy of our product. However, we found the hole would increase the friction between itself and the arrow, in order to solve this problem we need certain device to make bigger holes. Unfortunately, our experience had limited us from advance devices. The back up plan for this situation is to make another simple stabler on top of the lid, it worked as it decrease the accuracy of our product, which is a vital part for cross-bows.

Intension

Audience and purpose                                                                                                                                      Our targeted audience is children and novice physics students. This cross-bow toy is playful and demonstrates elastic to kinetic energy by the rubber band giving the arrow energy to move at a great velocity. The users are able to learn about energy transfer while playing; in addition, our product contains safety protection to avoid unexpected harm. The bright and dreamy color made it eye-catching and suitable for our consumers. Furthermore, the recyclable materials encourage students to protect the environment and DIY their own products.

Environmental impacts                                                                                                                                      One of our product’s intention is to encourage the action of recycle and protecting natural environments. The materials that are used are plastic bottle lid, rubber band, wood sticks and paper clips. Theses are materials that produce less harm to environment or command things we can find in our daily life. Adding on, our product contains zero usage of any kind of electricity, which reach the goal of zero electric waste or pollution.

Create and improve

After gathering materials, we created the base first and then the crossbow.

 

 

This is the result after the first creating class. However, we found out the lid did not go successfully as we expected. The plastic lid has a smooth, thick surface; it’s incredibly challenging for us to pinch perfect holes for the arrow.  We tried our best, and we realized the hole surged the arrow’s stability as it surged its friction, which had a massive impact on the crossbow.

 

.

 

In addition, we found that this type of base is more stable than our planned one.

 

 

Considering our targeted audience, we decided to paint it in bright colors to cover the dullness of the woods to make the product more eye-catching.

Testing Video and Feedback

 

Anonymous feedback 1: The arrow seemed sharp and pointy; I recommend improving the safety.

Anonymous feedback 2: Good demonstration of elastic energy; well done.  Maybe you guys can make the product safer.

 

 

This is our final result of the crossbow; in order to fix the friction problem, we changed our arrow stabler on top of the lid instead of using the lid itself. Furthermore, we replaced the arrow with paper straws to make it less harmful, and we will stick a piece of the blue tag on the tip of the straw to cover its sharpness.

Here is an organized graph of our changes and improvements.