Stop-Motion Animation

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Analysis of Walking

Walk A Attempt

Walk B

Walk C

Walk D

Term paper on Sonic the Hedgehog Physics

Kathleen O’Brien
10/09/09
The laws of Physics an Animation Universe Term paper – Super Sonic Physics

“He’s the fastest thing alive!” That is what we are led to believe about a cartoon character named, Sonic the Hedgehog. To accomplish this notion, Animation takes pains to create for its audience somewhat believable environments and concepts of physics. The paper will discuss an episode, “Heads or Tails”, and is the first, in the television series called “Sonic the Hedgehog” and how we are shown that Sonic is so fast. This episode can be found for viewing on youtube at the following URL http://www.youtube.com/watch?v=SCCQpyBpdaI&videos=9-us_pMw7xc&playnext_from=TL&playnext=1 . This series takes place on an Earth-like planet called Mobius. The surface of Mobius is polluted by an evil dictator that Sonic and his friends fight against. The planet is very similar to Earth in not only appearance but its laws of gravity are also similar. The only break in Mobius’ similarity to Earth is, although human-like creatures do inhabit the planet, the majority of the planet is populated by bipedal animals with human intelligence and robots that used to be bipedal animal. The one among those animals, who breaks the similarities to Earth the most is the above mentioned, Sonic the Hedgehog, a blue hedgehog, who has the ability to run at and maybe above, super sonic speeds. Sonic does not always comply to the laws of physics especially gravity. Among his friends it is worth mentioning that there are also individuals who are guilty of similar law breaking. All in all, the laws of Earth-like physics are maintained on Mobius unless entertainment value dictates otherwise.

As mentioned above the laws of physics, particularly gravity, on Mobius can be very Earth-like. Inanimate objects when thrown or dropped fall and land as they are expected to on Earth. Flowers when dropped gentle alight to the ground from air resistance. Hammers, tools and other heavy objects when thrown follow an arc although they always seem to make a comical noise when they do. There are hover crafts too in this world but we will ignore those because it is clear that they work by some form of science that we do not understand yet and for the most part they move as helicopter-like aircraft would be expected to move. Another object that defies gravity on Mobius to establish a mystical air is the power rings, rings made using a machine with, an unknown energy source. When created these rings float in the air and can be used to power machinery and Sonic’s speed boosts. Again this thought somewhat magical in appearance, can be classified as technology that we do not yet understand and so we will ignore it and accept it as common place on Mobius.

People and robots on Mobius are affected by being close to a fast moving subject, namely, Sonic further aiding the belief that someone as fast as Sonic could exist in an Earth-like environment. When Sonic runs past a being at his fast speeds they are either thrown off balance and fall over or they spin around very fast in a comical way. Sonic could be creating a swirling vortex that could cause someone to spin around when he runs past them. It is most likely when Sonic is running that fast it is like standing next to a speeding car or a train. The air suction that a moving object causes going at those speeds pulls you in and in some cases can throw you off balance or worse pull you in enough for you to get in the objects path and cause injury.

For all his speed, Sonic seems to need, most of the time anyway, sufficient time to slow down after speeding up just as all moving objects do when they decelerate. He rarely comes to a grinding halt, except at lower speeds for a gag’s sake, a lot of his deceleration time is off camera and we are only shown him finally coming to a sliding halt. This is most likely done due to time constraints since it would probably take up a lot of air time if they had to show him decelerating after every sonic boom. (His speed is also a good plot devise to quickly put characters into new locations without having to explain how they got there. Sonic just ran there fast.) Still he has to prepare for his stopping point and slow down in order to not over shoot it.

Sonic seems to be most bound to physics when he is not running at super speeds. As an example when sonic is sliding down a small vertical air shaft he has to force his arms and feet against the sides of the shaft. He does this to slow his descent and eventually comes to a stop just in time, if he did not he would have just fallen right down. (It is funny that while he was doing this he seemed worried despite the fact that he has been observed in other episodes running down the side of buildings faster than he could fall.) When riding down a slide he is pulled by gravity and descents down the incline as anyone would on a slide. It would appear that when he allows another force to move him he seems to have no problem with gravity or friction as long as he’s not running.

For a person, not as familiar with the show or its hero, to fully understand and appreciate Sonic’s speed some deliberation about his speed must be discussed or rather measured. With a little knowledge about acceleration you can get a rough measurement of the feats of speed that the hedgehog is capable of. Sonic can make a Sonic boom so he would have to be able to run at least 735 miles per hours as that is the speed at which an object can break the sound barrier. With that knowledge we can get an estimate of Sonic’s abilities to speed up and slow down. In the beginning of the episode Sonic is talking to his friends on screen and then Sonic runs off screen. Between the times that he was stopped and when we hear the boom is roughly a third of a second. From zero to 735 miles per hour in such a short time would mean that his acceleration is about 2205 mph/s. Acceleration like that is something you would expect from a high powered rifle bullet. It is amazing that Sonic, an organic life form, would be able to run at such speeds without causing extensive tissue, bone or organ damage from friction with the air and the force of acceleration. Supersonic jets have to be made of titanium to prevent heat damage from air at those speeds. Sonic, along with any other friend he is carrying with him, must be quite the hearty life forms to be able to endure such speeds unharmed.

One of Sonic’s amazing feats of speed is that he has the ability to run up any surface from sloped surfaces to vertical inclines. On Earth, humans are able to run up slopes and even with the right equipment like roller coasts do loops. Like Sonic, people on Earth can even run up walls, but only for a few moments, they cannot maintain the speed to defy gravity for very long. http://www.youtube.com/watch?v=nvOfUgXq1tk . Unlike Sonic who can accelerate enough to make it up a vertical wall. However as fast as Sonic is he would not be able to run on a ceiling as he is shown to do. Sonic could not run on a flat ceiling because according to Newton’s Action Reaction principle the moment that Sonic push his foot on the ceiling it would push back with the same force and then gravity would pull him down. In order to run on a surface that is not ground there would need to be an acceleration greater than the pull of gravity upwards on a ceiling. At 90 degrees, one would have to accelerate at the acceleration of gravity (9.8 m/s^2) in order to maintain constant speed. At more than a 90 degrees angle, less of your acceleration is in opposition to gravity. Sonic could still keep going if he was running fast enough, but at 180 degrees there is no component of his acceleration going upwards, so no matter how fast he is going he would not be able to stay on that surface. Though clearly on Mobius Sonic does run on ceilings. It would seem that Sonic has the ability of ‘selective gravity’ and he can decide when and where he wants gravity to be a factor, perhaps it is a super power.

Another example of Sonic’s powers of selective gravity is his ability to fall at will. Sonic is observed being thrown up into the air toward the end of the episode. He then stays there hanging in the air long enough to make a witty retort to a bad guy. He then attacks the bad guy and by no other force than his own will he accelerates back to the ground. It would seem that Sonic is also capable of flight when he feels inclined. It is obvious that this defiance of gravity is once again only for cartoon plot and comedy’s sake.

Mobius is not without great defiance of gravity and physics that is unrelated to comedy. One of the greatest exceptions to the rule is Sonic’s friend Miles “Tails” Prower, a two-tailed. Tails has the ability to spin his tails around and achieve flight. It would be impossible to rotate them the 360 degrees required to fly like a helicopter if his tails were attached to his body. Despite this, on Mobius it seems as long as Tails can spin his tails fast enough he will fly. When Tails spins his tails he spins them so fast that the viewer cannot see how he manages to achieve lift off. His tails blur from Tails’s speed and the audience suspends their belief that a two tailed fox cannot fly.

Mobius is an Earth-like place with Earth-like laws of physics. The fact that the planet looks and feels so familiar is what levels our expectation for it to be like ours in every way, including physics. When the otherwise happens thanks to Sonic and his friends, it is amazing to the audience, but still believable since the normal laws of physics occur and are maintained in this universe. Without having familiar boundaries of physics and gravity to comply with on Mobius, for the sake of entertainment wonder, it would be impossible to make the heroes stand out above the rest. Their abilities to do that which is normally physically impossible is what sets them above the rest and makes them admirable super heroes. For the sake of entertainment value physics can be thrown to the wind on Mobius.