File:Damped spring.gif - Wikipedia, the free encyclopedia

File:Damped spring.gif - Wikipedia, the free encyclopedia

Week 20 May 24

final

Week 19 May 17

review for final

Robot Inventory:
1. Get a manual, a box, a robot and an inventory sheet.
2. Organize everything onto a table and check everything off on your sheet.
3. Go over to the scrap table to find missing parts, and to put extras on the table. If something is broken ie. clutches are stripped, give them to me.
4. If you are still missing parts goto your neighbors and to find missing parts.
5. Once you have a complete set, let me know, and I will check everything off.

Week 18 May 10

Week of 18 May 10th

Objectives:

Agenda:

1. Mind Erase portion of Elitch's packet
2. Sidewinder or Seadragon portion of packet
3. the_physcis_of_phun.ppt.
4. Elitchs Excursion

* Look at rollercoast.Phys.pdf

Youtube video of Tower of Doom free fall

http://www.youtube.com/watch?v=y-LxZiVatrQ

http://www.youtube.com/watch?v=cxYDHxiAiD4&feature=related

Youtube video of Mind Eraser

http://www.youtube.com/watch?v=7r1q9_9FY6c

Mind Eraser

Park: Elitch Gardens

Ride Type: Steel Coaster Status: Operating since 6/2/1997

Category: Inverted

Cost: $10,000,000

Length: 2260' 6"

Height: 109' 3"

Max Speed: 49.7 mph

Inversions: 5

Duration: 1:36

Capacity: 1040 pph

Arrangement: Two 10-car trains that hold 20 riders/train.

Roller coaster rides are notorious for creating accelerations and g-forces which are capable of transforming stomach contents into airborne projectiles. As a rider starts the descent down the first drop, she begins a one-minute adventure filled with various sensations of weightlessness, heaviness, and jerkiness. The parts of the ride which are most responsible for these sensations of weightlessness and heaviness are the clothoid loops. The explanation for the various sensations experienced on a roller coaster loop are associated with Newton's laws of motion and the physics of circular motion.
A clothoid loop has a constantly curving shape with sections which resemble the curve of a circle (in actuality, it is considered to be a section of a cornu spiral having a constantly changing radius). A coaster rider is continuously altering her direction of motion while moving through the loop. At all times, the direction of motion could be described as being tangent to the loop. This change in direction is caused by the presence of unbalanced forces and results in an acceleration. Not only is there an acceleration, the magnitude and direction of the acceleration is continuously changing. Within nearly a one second time interval, the riders may experience accelerations of 20 m/s/s downwards to 30 m/s/s upwards; such drastic changes in acceleration normally occur as the rider moves from the top of the loop to the bottom of the loop. These drastic changes in accelerations are the cause of much of the thrill (and the occasionally dizziness) experienced by coaster riders.
To understand the feelings of weightlessness and heaviness experienced while riding through a loop, it is important to think about the forces acting upon the riders. To simplify the discussion, we will assume that there are negligible amounts of air resistance acting upon the riders. Thus, the only forces exerted upon the riders are the force of gravity and the normal force (the force of the seat pushing up on the rider). The force of gravity is at all times directed downwards and the normal force is at all times directed perpendicular to the seat of the car. Since the orientation of the car on the track is continuously changing, the normal force is continuously changing its direction. The magnitude and direction of these two forces during the motion through the loop are depicted in the animation below.

For an object to move along a circular path at a constant speed, there must be a net inward force acting upon the rider. This is commonly referred to as the centripetal force requirement. The motion through a coaster loop isn't precisely an example of moving in a circle at constant speed since the loop is neither circular not the speed constant. Nonetheless, because of the similarity of the motion along the loop's path to uniform circular motion, principles of uniform circular motion can be applied to the rider. The net force acting upon the rider has an inwards direction (towards the center of the circle). Since the net force is the vector sum of all the forces, the head-to-tail addition of the normal force and the gravity force should sum to a resultant force which points inward. The diagram below depicts the free-body diagrams for a rider at four locations along the loop. The diagram also shows that the vector sum of the two forces (i.e., the net force) points mostly towards the center of the loop for each of the locations.

Feelings of weightlessness and heaviness are associated with the normal force; they have little to do with the force of gravity. A person who feels weightless has not lost weight. The force of gravity acting upon the person is the same magnitude as it always is. Observe that in the animation above the force of gravity is everywhere the same. The normal force however has a small magnitude at the top of the loop (where the rider often feels weightless) and a large magnitude at the bottom of the loop (where the rider often feels heavy). The normal force is large at the bottom of the loop because in order for the net force to be directed inward, the normal force must be greater than the outward gravity force. At the top of the loop, the gravity force is directed inward and thus, there is no need for a large normal force in order to sustain the circular motion. The fact that a rider experiences a large force exerted by the seat upon her body when at the bottom of the loop is the explanation of why she feels heavy. In actuality, she is not heavier; she is only experiencing the large magnitude of force which is normally exerted by seats upon heavy people while at rest.

The breaking of the sound barrier is not just an audible phenomenon. As a new picture from the U.S. military shows, Mach 1 can be quite visual.

This widely circulated new photo shows a Air Force F-22 Raptor aircraft participating in an exercise in the Gulf of Alaska June 22, 2009 as it executes a supersonic flyby over the flight deck of the aircraft carrier USS John C. Stennis.

The visual phenomenon, which sometimes but not always accompanies the breaking of the sound barrier, has also been seen with nuclear blasts and just after space shuttles launches, too. A vapor cone was photographed as the Apollo 11 moon-landing mission rocketed skyward in 1969.

The phenomenon is not well studied. Scientists refer to it as a vapor cone, shock collar, or shock egg, and it's thought to be created by what's called a Prandtl-Glauert singularity.

Here's what scientists think happens:

A layer of water droplets gets trapped between two high-pressure surfaces of air. In humid conditions, condensation can gather in the trough between two crests of the sound waves produced by the jet. This effect does not necessarily coincide with the breaking of the sound barrier, although it can. To learn more, click here.

The aircraft carrier was participating in Northern Edge 2009, an exercise focused on detecting and tracking things at sea, in the air and on land.

· Gallery: Breaking the Sound Barrier

· The Greatest Explosions Ever

· What is a Sonic Boom?

Week 17 May 3

Week 17 May 3

Objectives:

1. Students will be able to write a short constructive response on what the G force formula is, and how it works.
2. Students will be able to write a short constructive response on centripital force.

Agenda:

1. Worksheet on the physics of roller coasters (Tower of Doom or Sidewinder)
2. Go to Elitch's and take video of rides so the kids can come up with data
3. rollercoasterPhys.pdf
4. G Force ppt.
5. Create a roller coaster which will complete as many loops as possible, taking into consideration friction, potential and kinetic energy
6. Centripital force notes (img414.pdf, img415.pdf, img416.pdf, img 417.pdf,
7. gforce.doc (worksheet in folder)
8. coaster.doc (worksheet in folder)

9. Motion Sensor with TI of forces involving roller coasters.

Interesting Websites:

http://phet.colorado.edu/simulations/sims.php?sim=Ladybug_Revolution

http://phet.colorado.edu/simulations/sims.php?sim=Energy_Skate_Park

put copy of G-Force table here (its in folder)

Website that shows the G-forces of different loops. http://www.coasterdynamics.com/CoasterDynamics/CLabIntro.html

The g-force of an object is 0 g in any weightless environment such as free-fall or an orbiting satellite and is 1 g (upwards) for a stationary object on the Earth's surface. However, g-forces can be much greater than 1 g on, for instance, accelerating rockets, centrifuges, and rollercoasters.

Human tolerances depend on the magnitude of the g-force, the length of time it is applied, the direction it acts, the location of application, and the posture of the body.
The human body is flexible and deformable, particularly the softer tissues. A hard slap on the face may briefly impose hundreds of g locally but not produce any real damage; a constant 16 g for a minute, however, may be deadly. When vibration is experienced, relatively low peak g levels can be severely damaging if they are at the resonance frequency of organs and connective tissues.
To some degree, g-tolerance can be trainable, and there is also considerable variation in innate ability between individuals. In addition, some illnesses, particularly cardiovascular problems, reduce g-tolerance.
The human body is better at surviving g-forces that are perpendicular to the spine. In general when the acceleration is forwards, so that the g-force pushes the body backwards (colloquially known as "eyeballs in") a much higher tolerance is shown than when the acceleration is backwards, and the g-force is pushing the body forwards ("eyeballs out") since blood vessels in the retina appear more sensitive in the latter direction.
Early experiments showed that untrained humans were able to tolerate 17 g eyeballs-in (compared to 12 g eyeballs-out) for several minutes without loss of consciousness or apparent long-term harm. The record for peak experimental horizontal g-force tolerance is held by acceleration pioneer John Stapp, in a series of rocket sled deleration experiments in which he survived forces up to 46.2 times the force of gravity for less than a second.
John Stapp was subjected to 15 g for 0.6 second and a peak of 22 g during a 19 March 1954 rocket sled test.

A top-fuel dragster can accelerate from zero to 100 miles per hour (160 km/h) in 0.86 second. This is an acceleration of 5.3 g. Accelerometers are often calibrated to measure g-force along one or more axes. If a stationary, single-axis accelerometer is oriented so that its measuring axis is horizontal, its output will be 0 g, and it will continue to be 0 g if mounted in an automobile traveling at a constant velocity on a level road. But if the car driver brakes sharply, the accelerometer will read about −0.9 g, corresponding to a backward acceleration. However, if the accelerometer is rotated by 90°, so that its axis points upwards, it will read +1 g upwards even though still stationary. In that situation, the accelerometer is subject to two forces: the gravitational force and the ground reaction force of the surface it is resting on.

Vertical axis g-force
Aircraft, in particular, exert g-force along the axis aligned with the spine. This causes significant variation in blood pressure along the length of the subject's body, which limits the maximum g-forces that can be tolerated.
In aircraft, g-forces are often towards the feet, which forces blood away from the head; this causes problems with the eyes and brain in particular. As g-forces increase a Brownout can occur, where the vision loses hue. If g-force is increased further tunnel vision will appear, and then at still higher g, loss of vision, while consciousness is maintained. This is termed "blacking out". Beyond this point loss of consciousness will occur, sometimes known as "G-LOC" ("loc" stands for "loss of consciousness"). Beyond G-LOC, if g-forces are not quickly reduced, death can occur.
While tolerance varies, with g-forces towards the feet, a typical person can handle about 5 g (49m/s²) before g-loc, but through the combination of special g-suits and efforts to strain muscles—both of which act to force blood back into the brain—modern pilots can typically handle 9 g (88 m/s²) sustained (for a period of time) or more (see High-G training).
Resistance to "negative" or upward g's, which drive blood to the head, is much lower. This limit is typically in the −2 to −3 g (−20 m/s² to −30 m/s²) range. The subject's vision turns red, referred to as a red out. This is probably because capillaries in the eyes swell or burst under

When “g-forces” are discussed, we are usually talking about the apparent force that an object experiences due to acceleration, either from a rocket force or a rotational motion.

Rocket: Suppose that you know the acceleration of an object, say of an astronaut taking off in the shuttle. We can easily calculate the “g-force” on him/her. Suppose that his/her acceleration is 29.4 m/s^2 upward. This is three times the acceleration of gravity, so the astronaut will feel an apparent force downward equal to 3 times his/her weight, PLUS the normal force of gravity. Thus the total “g-force” on the person will be “4 g's”

An object moving in a circle has an acceleration toward the center of the circle given by:a = v^2/r where “v” is the velocity of the object in m/s and “r” is the radius of the circle in meters.If you use this equation and you calculate the acceleration of a person moving in a horizontal circle to be 29.4 m/s^2, that person is experiencing “3 g's” toward the center of the circle. Assuming that he/she is on Earth, there is also the Earth's force downward on the person. So the person has 3 g's horizontally and 1 g downward. (You'd have to use vectors to add these two, and let's not fool with that now.)

By Mike Leahy with Duncan Banks

Watching films like Top Gun it's easy to see the appeal of being a fighter pilot, but would Tom Cruise have made a real fighter pilot, let alone Zeron and me? The cockpit of a fighter plane is a very hostile environment. Because of the altitude at which they may fly there is little naturally available oxygen and the outside temperature is very low. The movement of the plane can result in motion sickness, and the forces exerted on the body by one of the most advanced aerobatic aircraft in the world is literally crushing.

Motion sickness and the vestibular system
During our competition for a flight in one of the United States Air Force F-16s, Zeron and I had our first experience of flying in an aerobatic aircraft with a pair of Extra 300 stunt planes. We spent under half an hour reeling around the sky in a simulated dog-fight with each other. My pilot was Andy Cubin, an ex-Red Arrow pilot and he really showed me what a modern piston engine stunt plane can do. He tried vertical rolls, break turns, barrel rolls and loops. Concentrating on reading a line from a piece of paper while doing a wicked vertical roll nearly did the trick for me, because my eyes focused on what looked like a stationary object, but my ears told me that I was being moved about quite vigorously. When we landed we felt suitably sick, as many people would, but why? Why is the modern aircraft pilot told to believe their instruments and not their senses?

The vestibular system is situated in the inner ear (see Figure 1 below) and together with our eyes, and various other parts of our body (for example, our toes) it helps us to balance.

Figure 1. A cross section of the human ear
(Click here² to view a bigger version)

As our eyes read the visual signals around us, channels of fluid within our inner ear called the semi-circular canals sense movements through small hairs, called cilia, which are suspended within the fluid. If you get hold of a bucket of water and spin it, much of the water it contains will remain still because of inertia [i.e. because it has mass and wants to remain at rest unless affected by a force]. Much the same happens within our ears. As we spin our heads the semi-circular canals, and the cilia they contain, move with our heads, whereas the fluid contained within the canals tends to stay still. This causes the cilia to move through the fluid, and they sway in a similar way to reeds in a fast moving stream. This movement is picked up by sensors at the bottom of the cilia which pass messages to the brain. Thus the semicircular canals are able to detect rotation of the head (angular velocity).

In addition to the semi-circular canals, we have devices called otoliths within our inner ear. These look like golf balls on tees and they enable us to detect the static position of the head and changes of speed and motion in a straight line (linear acceleration) by bending slightly. This tells the brain the position of our head relative to gravity. Just about all of these systems can be fooled when flying a plane, especially if it is changing direction rapidly, or accelerating.

Mixed Messages
Should the messages from the eyes not match the messages from the vestibular system the brain becomes confused. It has been suggested that the sensation is very similar to that which would be experienced had we ingested a neurotoxin (a toxin which attacks the nervous system), a real danger in prehistoric times. For example, if you ate the wrong type of berry, the body would defend itself by vomiting. If we are to make fighter pilots this is one of the first things that we will have to overcome.

There are two methods. The first would be to use drugs, but that would be cheating. The second would be to keep going up in planes until our bodies, in particular our senses, got used to it. Hence, we were spun around in gyroscopes for the best part of an afternoon.

G-Force
G-force is a killer. In fact, the effects of g-force was, as long ago as the Second World War, causing the death of pilots who either lost consciousness or were unable to bale out of their planes. The 'g' refers to 'gravity' and while the force has little to do with gravity it provides an easy to understand measurement of what g-force is - essentially acceleration. Most people think of acceleration as an increase in speed. This is how the word is generally used when thinking about cars and motorbikes, but in purely scientific terms acceleration is a change in velocity (change in speed and/or direction). It's weird to think that a car that is braking or turning a corner is actually accelerating if the word was used in its scientific sense.

We measure the force we feel as we accelerate in multiples of gravity - gs. The force you feel under the influence of gravity is 1g. Put simply, if you were to weigh 80kg (like me) then at 1g you will still weigh 80kg. In most people's day-to-day life they may feel a little ' g ' force when accelerating hard, cornering or braking in a car. This would probably never exceed 1g or so, although forces as high as 12g can result from car crashes. At a fairground you might experience a couple of g and if you were straightening up at the bottom of the big descent in 'The Big One' roller coaster at Blackpool Pleasure Beach you would experience about 3g. At that moment I would weigh in at 240kg (that's about forty stone).

In the Extra 300 stunt planes in the UK, Zeron and I experienced 6.5g, with quite a fast onset, but only for a few seconds. If we were to go out and play with the big boys in their F-16s we would have to endure over 9g for as long as ten or twenty seconds. Before doing that safely we would have to prove that we were man enough, and the only safe way to do so was in a controlled environment - a horrible giant centrifuge in the USA.

The centrifuge works much like a spin dryer, but instead of squeezing water out of clothes against the side of the drum, as this centrifuge spins faster and faster we will be pushed harder and harder into our seat. Under these conditions anything that can move will move, including the blood in your body. In an F-16 fighter jet pulling an aggressive break turn it is possible to experience 9g. That means that in a tight turn I would weigh 720kg (nearly three quarters of a tonne).

Such forces are bound to mess up the body. The first effect that is noticed by the pilot is that it is difficult to breathe. This is because the g-force is pulling the ribs down, which empties the air from the lungs. This isn't the most dangerous effect, but it does wear you out. The most dangerous effect is that blood is pulled away from the brain and pools in the legs and feet. This is exacerbated because the internal organs tend to be pulled down through the body, meaning that blood has to be forced further to get to the brain. After a short time experiencing 'high-g' turns, the eyes lose peripheral vision - giving tunnel vision and you may only be able to see in black and white (greying out). If the turn continues all vision is lost. This is called a blackout. Should the turn keep going the pilot would risk losing consciousness. It is called a g-LOC (g-induced Loss Of Consciousness).

A healthy person would expect to start suffering from a loss of vision and other g induced problems at 5 or 6g. After that they usually need help. The first line of defence, if technological aids aren't available, and certainly the most important aspect of resisting the negative effects of 'g' force is the 'Strain'. It's an exhausting exercise which involves contracting as many muscles as possible in your feet, calves, upper leg, stomach muscles and butt cheeks while allowing your upper body to remain relaxed so that breathing is relatively easy. It sounds easy enough, but when each of us was brought out to the front of the 'class' at the USAF base to practise it, we found it was far from straightforward.

First, my feet had to be positioned in a pigeon toed way. Then I had to curl up my toes and pull my feet back using my calf muscles. My stomach and upper leg muscles then had to be contracted as if I were expecting a blow to the torso. All this while relaxing my shoulders and letting them drop. After four or five attempts I managed to synchronise all these movements quickly enough, so that if I knew a hard turn was coming during flight I could 'put on my strain' almost instantly.

Other, less critical effects of high-g turns include many burst blood vessels, leading to a rash known as the 'geezles', piles and bruised butt cheeks.

Altitude, pressure and oxygen availability. At altitude, atmospheric pressure is greatly reduced. Put simply this is because there are more molecules of any gas per unit volume of air at sea level than high in the atmosphere because they are being 'squashed' down by the column of air above them. This means that it becomes difficult to breathe because one of the molecules we need is oxygen, and at altitude there is far less oxygen available. In addition to oxygen deprivation, the lack of pressure itself causes problems. It's worth noting that should an aircraft suddenly de-pressurise at an altitude of fifty thousand feet some gasses that had been absorbed by the blood would instantly return to their gaseous state, causing the blood to behave almost as if it were boiling. Hopefully we won't ever have to deal with that problem, but should we be at altitude and suffer some sort of technical problem it is worth knowing about.

The technology
G-suits. Before we tried the centrifuge we still needed to learn about the technological aids we may be able to use when we go up in a fighter jet. The first was the g-suit. These look like a pair of cowboy's chaps - trousers with nothing around the butt, a bit like one of the Village People used to wear. The only difference is that it has a tube, like a flaccid and convoluted member hanging from one leg. Apart from the tube the g-suit was pretty unobtrusive at first, but in the cockpit of a plane it becomes 'alive'. The tube is plugged into a supply of compressed air, and when the pilot experiences in excess of 5g or so the legs of the suit inflate. This presses down on the blood vessels in the legs, preventing blood pooling, and helping to avoid loss of blood from the head. It is estimated that you can increase your g-tolerance by 1.5g when using these.

Combat Edge. The second piece of equipment was the 'Combat Edge' suit. This consists of two parts. Firstly, there is an inflatable singlet, with a bladder at the back of the neck, and rather than merely inflate under the influence of g-force it makes sure that the blood stays in the right place with a more sophisticated inflation strategy. This is supplemented by a 'Combat Edge' mask, which forces oxygen into a pilot's mouth at forty pounds per square inch, should the aircraft exceed a certain g-force. I tried the mask at sea level under neutral-g conditions (i.e. standing on the ground). Without my chest being subject to 6 or 7g it was difficult to breathe out, which is the opposite to what would happen under g-force, and as soon as I relaxed oxygen forced its way back into my lungs. Under high-gs this should help equal things up a bit and help the pilot to breathe easily. After doing the breathing exercise I could see how the 'Combat Edge' equipment would be a definite help.

Oxygen supplies. To overcome the lack of oxygen at altitude, oxygen is fed through masks from oxygen cylinders to compensate. In addition to supplying enough oxygen to breathe easily, extra oxygen helps to reduce some of the effects of g-force. When less blood is getting to the brain due to the effects of g-force, extra oxygen can be supplied to help make sure that what blood gets there is well oxygenated, even when breathing is difficult.

Would either Zeron or I have made good fighter pilots?
Although I got to go up in the F-16 I could never have been a fighter pilot because I suffer from asthma and am slightly colour blind (in as much as I know that blood is red and grass is green, but I can't pass any of the tests). Zeron might have made the grade. The g-loc events he suffered may have been 'one-offs' due to him choking on a glass of water, but I think that the real thing to remember is that it's definitely not as easy as Tom Cruise makes it look in Top Gun and although I didn't suffer from g-loc I didn't have to operate a combat fighter at the same time with all its complex instruments and weapons systems.

Week 16 April 26

programming robots

1. Blood hound

2. Line tracker

3. Guest speaker programmer

4. Programming Robots ppt. (Put in link)

5. Bodyworks Link To Manual (In folder)

SolidWorks is a parasolid-based solid modeler, and utilizes a parametric feature-based approach to create models and assemblies.

Parameters refer to constraints whose values determine the shape or geometry of the model or assembly. Parameters can be either numeric parameters, such as line lengths or circle diameters, or geometric parameters, such as tangent, parallel, concentric, horizontal or vertical, etc. Numeric parameters can be associated with each other through the use of relations, which allows them to capture design intent.

Design intent is how the creator of the part wants it to respond to changes and updates. For example, you would want the hole at the top of a beverage can to stay at the top surface, regardless of the height or size of the can. SolidWorks allows you to specify that the hole is a feature on the top surface, and will then honor your design intent no matter what the height you later gave to the can.

Features refer to the building blocks of the part. They are the shapes and operations that construct the part. Shape-based features typically begin with a 2D or 3D sketch of shapes such as bosses, holes, slots, etc. This shape is then extruded or cut to add or remove material from the part. Operation-based features are not sketch-based, and include features such fillets, chamfers, shells, applying draft to the faces of a part, etc.

Building a model in SolidWorks usually starts with a 2D sketch (although 3D sketches are available for power users). The sketch consists of geometry such as points, lines, arcs, conics (with exception to hyperbola), and splines. Dimensions are added to the sketch to define the size and location of the geometry. Relations are used to define attributes such as tangency, parallelism, perpendicularity, and concentricity. The parametric nature of SolidWorks means that the dimensions and relations drive the geometry, not the other way around. The dimensions in the sketch can be controlled independently, or by relationships to other parameters inside or outside of the sketch.

SolidWorks pioneered the ability of a user to roll back through the history of the part in order to make changes, add additional features, or change the sequence in which operations are performed.^[3] Later feature-based solid modeling software also copied this idea.

In an assembly, the analog to sketch relations are mates. Just as sketch relations define conditions such as tangency, parallelism, and concentricity with respect to sketch geometry, assembly mates define equivalent relations with respect to the individual parts or components, allowing the easy construction of assemblies. SolidWorks also includes additional advanced mating features such as gear and cam follower mates, which allow modeled gear assemblies to accurately reproduce the rotational movement of an actual gear train.

Finally, drawings can be created either from parts or assemblies. Views are automatically generated from the solid model, and notes, dimensions and tolerances can then be easily added to the drawing as needed. The drawing module includes most paper sizes and standards (ANSI, ISO, DIN, GOST, JIS, BSI and GB).

Week 15 April 20

Week 15 of April 20th

Objective:

1. Gaming ppt.
2. Squarebot makes a square
3. Programming robots ppt.

Agenda:

Notes:

A game's physics programmer is dedicated to developing the physics a game will employ. Typically, a game will only simulate a few aspects of real-world physics. For example, a space game may need simulated gravity, but would not have any need for simulating water viscosity.
Since processing cycles are always at a premium, physics programmers may employ "shortcuts" that are computationally inexpensive, but look and act "good enough" for the game in question. Sometimes, a specific subset of situations is specified and the physical outcome of such situations are stored in a record of some sort and are never computed at runtime at all.
Some physics programmers may even delve into the difficult tasks of inverse kinematics and other motions attributed to game characters, but increasingly these motions are assigned via motion capture libraries so as not to overload the CPU with complex calculations.
For a role-playing game such as Might and Magic, only one physics programmer may be needed. For a complex combat game such as Battlefield 1942, teams of several physics programmers may be required.