Filming & editing

4/11/15
Updated by Angela

After the construction process was finished I filmed the whole trip of the car in our constructed rollercoaster track as well as took a few photos of the track. Next I went home and used software such as Final Cut Pro and Adobe After Effects to edit the videos into a film featuring the rollercoaster. The film is attached below.

Sadly, the completion of this film marks the termination of our rollercoaster task. The process of designing and constructing a rollercoaster was really fun and this task is definitely a memorable one. But I will leave it here, and hope you enjoyed reading about this process! On behalf of my whole group, thank you for sticking with us, and goodbye! 

Construction of the Roller Coaster

2/11/15
Updated by Bill and Lilian

30/10/15 (Friday)
After receiving the completed diagram from Angela we proceeded to prepare for the construction of the roller coaster.

On Friday afternoon we purchased the materials we required for the rollercoaster. These materials included:

• Skewers

• PVA Glue

• 500 Paddle pop sticks

• Poster card

• Cardboard

• A toy car

In total this costed around $20.

31/10/15 (Saturday)

Today we built the roller coaster and completed it to an extent.

Process:

1 - Drill 0.3cm wide holes in each end of each paddle pop stick.

3 - Created box structures that would form the foundation of the roller coaster.

The project required 35 boxes in total and thus this took us several hours. They were also frustrating  and time consuming to make as they were unstable and had a tendency to tilt. Glue was later used as a counter measure.

4 - Positioning all the boxes in the right places and taping them to the base cardboard.

5 - Cut out the tracks from the poster card, each strip was about 4cm wide.

6 - Blue tacking each track to the underlying structure

7 - One strip of track was bent into a tear drop shape and used for the loop.

8 - Cut curves out of the poster card for when the track needed to turn. )e.g. banked turn and end)

9 - Cut off any pretruding skewers

10 - Add a clamp like mechanism 50cm from the end of the track to cause friction that would stop the car

(Note: We didn't have enough poaster card to complete the track at the very end so the car

simply goes onto the cardboard base. However, if does stop 50cm from the end of where the track was supposed to end.)

This process took around 8 hours.

At the conclusion of the roller coaster's construction, we realised we had made a few errors.

The energy acquired by the car at the initial decent was not enough to propel it up the loop.

Additionally, the car kept on derailing as their were no barriers.

These issues were later fixed on Monday morning before exams.

2/11/15 (Monday)

As stated above there were several issues with the completed model that were addressed today.

We spent 2 hours making adjustments to the rollercoaster.

Firstly we increased the height and steepness of the initial decent. We raised it from 30cm to 60cm

and the gradient was 2 instead of 1. This addressed the issue of a lack of energy. Additionally, we also made the loop smaller, making it easier for the car to scale.

In response to the constant derailing, we added barriers at key points made out of duel paddlepop sticks. This was efficient as the car no longer derailed.

The final product looked like this:

Next, we filmed our showcase video - However that will be covered by Angela in the next post.

More on design, research, group members etc

1/11/15
Updated by Angela

So it was decided last Wednesday that Bill would join this group. His job would be to assist Lilian in sourcing materials and making the rollercoaster, because that task is quite substantial.

I also conducted some further research into rollercoaster mechanisms to help me design it. The results I found are as follows:

A brake system installed into the track can help a rollercoaster stop either in an emergency or at the end of the journey. This includes clamps built anywhere into the track that the rollercoaster needs to stop at. These are able to clamp down on the wheels under the car, hence creating a frictional drag and slowing the rollercoaster down. Brain, Marshall. 2008, How Stuff Works, Chartwell Books, New York, US (accessed 23-10-15)

Moreover I finished a final sketch of what the rollercoaster track will look like on Friday afternoon. A picture is attached below.

Potential designs (sketches)

24/10/15
Updated by Angela

Using the research conducted by the others, I sketched a rough draft of what could potentially be a design for the rollercoaster. However I have to find some way to made it not wider than 10 cm (as stated by the requirements).

Here is also a website includes a potential template of how Lilian could build the rollercoaster, as well as ideas for materials she could build it out of. Below is also a picture of the model rollercoaster. 

http://www.instructables.com/id/Wooden-Roller-coaster-model-EngelsEnglish/  

Features of a rollercoaster

23/10/15

Updated by Selina

Here includes research of various features that might be included in the rollercoaster.

• Banked turns - A banked curve induces a sensation of being thrown sideways by turning the car sideways. The car is tilted, but the trick is to tilt the track just the right amount. Wayne, Tony . (2000). Curves. Available: http://vip.vast.org/BOOK/CURVES/HOME.HTM. Last accessed 13/10/15. 
  

• Vertical loop - The generic roller vertical loop can either be in a circular or teardrop shape. It is where a section of the track completes a 360 degree circle, is the most basic of roller coaster inversions. At the top of the loop, riders are completely inverted. Rollercoasters today employ clothoid loops rather than circular loops. This is because circular loops require greater entry speeds to complete the loop. If the radius is reduced at the top of the loop, the centripetal acceleration is increased sufficiently to keep the passengers and the train from slowing too much as they move through the loop. Berry, Nick. (24/3/14). Why roller coaster loops are never circular . Available: http://gizmodo.com/why-roller-coaster-loops-are-never-circular-1549063718. Last accessed 14/10/15. 
  

• Corkscrew that has three helices - A corkscrew is an inversion that resembles a vertical look that has been stretched so that the entrance and exit points are a distance away from each other. It includes three loops in a row. Wikia. (2004). Inversion . Available: http://rollercoaster.wikia.com/wiki/Inversions#Vertical_Loop. Last accessed 14/10/15. 
  
   

Further energy transformations

17/10/15
Updated by Siming

Here is some further research into energy transformations in a rollercoaster.

·     The ride often begins as a chain and motor (or other mechanical device) exerting a force on the train of cars to lift the train to the top of a hill.

·     Once the cars are lifted to the top of the hill, gravity takes over and the remainder of the ride is an experience in energy transformation.

·     At the top of the hill, the cars possess a large quantity of potential energy. The car's large quantity of potential energy is due to the fact that they are elevated to a large height above the ground.

·     As the cars descend the first drop they lose much of this potential energy in accord with their loss of height. The cars subsequently gain kinetic energy. The train of coaster cars speeds up as they lose height. Thus, their original potential energy (due to their large height) is transformed into kinetic energy (revealed by their high speeds).

·    As the ride continues, the train of cars are continuously losing and gaining height. Each gain in height corresponds to the loss of speed as kinetic energy (due to speed) is transformed into potential energy (due to height).

·    Each loss in height corresponds to a gain of speed as potential energy (due to height) is transformed into kinetic energy (due to speed). The transformation of mechanical energy changes from the form of potential to the form of kinetic and vice versa.

·     On a well designed roller coaster loop, the riders will not be able to sense when they are traveling upside down. This is done by making sure the force that is exerted on the rider is at least equal to the weight of the rider. Centripetal force applied to the track depends on the velocity of the car. In order to apply enough centripetal acceleration the roller coaster car has to either be traveling very fast or the radius of the loop has to be made small.

·    The underlying principle of all roller coasters is the law of conservation of energy, which describes how energy can neither be lost nor created; energy is only transferred from one form to another. The first hill of a roller coaster is always the highest point of the roller coaster because friction and drag immediately begin robbing the car of energy. At the top of the first hill, a car's energy is almost entirely gravitational potential energy.

·    The typical roller coaster works by gravity. There are no motors used to power it during the ride. Starting from rest, it simply descends down a steep hill, and converts the (stored) gravitational potential energy into kinetic energy, by gaining speed. A small amount of the energy is lost due to friction, which is why it's impossible for a roller coaster to return to its original height after the ride is over. 

·     On a well designed roller coaster loop, the riders will not be able to sense when they are traveling upside down. This is done by making sure the force that is exerted on the rider is at least equal to the weight of the rider. Centripetal force applied to the track depends on the velocity of the car. In order to apply enough centripetal acceleration the roller coaster car has to either be traveling very fast or the radius of the loop has to be made small.

·     The underlying principle of all roller coasters is the law of conservation of energy, which describes how energy can neither be lost nor created; energy is only transferred from one form to another. The first hill of a roller coaster is always the highest point of the roller coaster because friction and drag immediately begin robbing the car of energy. At the top of the first hill, a car's energy is almost entirely gravitational potential energy.

Bibliography:

Engineering K-PhD Program, Pratt School of Engineering, Duke University. Lesson: Physics of Roller Coasters. Last modified: November 4, 2015. https://www.teachengineering.org/view_lesson.php?url=collection/duk_/lessons/duk_rollercoaster_music_less/duk_rollercoaster_music_less.xml

Roller Coaster Physics. 2009 – 2015. http://www.real-world-physics-problems.com/roller-coaster-physics.html

Wayne, Tony. (1998) Coaster Physics: An Educational Guide to Rollercoaster Design and Physics for Teachers and Students

Energy transformation

14/10/15
Updated by Selina 


Today I made progress on the research of energy transformations in a rollercoaster. Findings and sources are as below.


The rollercoaster's total energy through the entire ride will be derived from its gravitational potential energy at the start of the ride. Make sure that the hills throughout the ride are not higher than the start as the rollercoaster would not have enough energy to climb the hills.

The rollercoaster will slowly lose its energy due to forces such as friction and air resistance. This allows the rollercoaster to stop without any assistance as all its energy is displaced from the forces. At the peak of a rollercoaster hill, the rollercoaster car goes from travelling upwards to flat and then to moving downward. this change in direction is known as acceleration and this acceleration makes riders feel as if a force is acting on them. Similarly, at the bottom of hills riders feel as if a force is pushing them down into their seats. These forces can be referred to in terms of gravity and are called gravitational forces, or g-forces. One 'g' is the force applied by gravity while standing on Earth at sea level. 

Cars in rollercoasters always move the fastest at the bottom of hills. This is related to the concept that at the bottom of hills, all of the potential energy has been converted to kinetic energy, which leads to increased speed. Likewise, cars always travel the slowest at their highest point, which is the top of hills. Because of this, rollercoaster cars can only make it through loops if they have enough speed at the top of the loop. This minimum speed is referred to as the critical velocity, and is equal to the square root of the radius of the loop multiplied by the gravitational amount. (vc = 1/2rg)   

Kinetic energy - the energy that an object possesses due to its motion (dependent upon the mass of the object and the speed of the object.). As the cars of a rollercoaster loses much of its potential energy in accord with the loss of height, and subsequently gains kinetic energy. The train of coaster cars speed up as they lose height. Thus, their original potential energy (due to their large height) is transformed into kinetic energy (revealed by their high speeds). Each gain in height corresponds to the loss of speed as kinetic energy (due to speed) is transformed into potential energy (due to height). Each loss in height corresponds to a gain of speed as potential energy (due to height) is transformed into kinetic energy (due to speed).

Potential energy - the energy that an object has due to its position in a force field or that a system has due to the configuration of its parts. The type of potential energy that is relevant to our rollercoaster is the gravitational potential energy of an object depending on its vertical position. The higher the rollercoaster, the larger the gravitational potential energy.

Forces - a push or pull upon an object resulting from the object's interaction with another object. The forces acting on the rollercoaster include gravity, friction air resistance. The force of gravity is an internal force and thus any work done by it does not change the total energy of the train of cars. Friction would cause some of the potential energy the cars started off with to decrease, when the wheels rub against the track. Air resistance also takes away some of the energy as well.

Mechanical energy - mechanical energy is the energy that is possessed by an object due to its motion or due to its position. Mechanical energy can be either kinetic energy (energy of motion) or potential energy (stored energy of position). This applies to a rollercoaster as it has gravitational potential energy due to its height and kinetic energy as the rollercoaster travels downhill.

Bibliography:

• D'Agustino, Steven, Adaption, Resistance and Access to Instructional Technologies, Fordham, 2011, Print (Accessed 14/10/15)
• Hewitt, Paul G (1998). Instructor's Manual, Conceptual Physics. London: Addison Wesley. 398. (Accessed 14/10/15)
• Woodford, Chris. (2008) Rollercoasters. Retrieved from http://www.explainthatstuff.com/rollercoasters.html. (Accessed 14/10/15)