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)

Initial planning

14/10/15
Updated by Angela

Today we split up the workload between group members and made a plan of the timeframes intended for the making of the rollercoaster.

Siming & Selina: 

• Research & Information
• Bibliography
• Blogging

Angela: 

• Design & drawing of rollercoaster
• Making the film 
• Blogging

Lilian:

• Sourcing equipment for the rollercoaster
• Making the rollercoaster
• Blogging

Timeplan:

Week 2: Conduct research 

Week 3: Design the rollercoaster & draw drafts

Week 4: Make the rollercoaster & conduct trial testings

Week 5: Refine rollercoaster & make film