求半物理仿真或者全物理仿真的英文文献及其翻译!

求半物理仿真或者全物理仿真的英文文献及其翻译!
毕设要求一篇翻译,毕设题目是卫星半物理仿真监控软件设计与开发,跟这个有关的文献都行,万急啊!

Physical simulation allows simulated agents to behave in a physically realistic fashion. This means that agents in the simulated world can be configured to behave just as real objects do, according to the laws of physics. If a ball is placed in the air above a floor, for example, physical simulation can be used to make the ball realistically fall toward the floor and bounce. Among other things, physical simulation can be used for realistic simulation of robots, vehicles and animals. The current version of breve uses portions of the excellent ODE physical simulation engine.
When to Use Physical Simulation
In many circumstances, users wish to write simulations that use certain aspects of physics, but not others. In these situations it is tempting to enable physical simulation, but this often opens the door to other sorts of complications. Physical simulation is slower, more complicated and inherently less stable than non-physical simulation. It is often far more effective to use "pseudo-physics" in which you implement some physical simulation features without enabling full physical simulation.
One example is a simulation which requires gravity for "ballistic" (non-Multibody Real) objects. Though the effects of gravity can be enabled using physical simulation, a more robust and far more efficient approach is to simply set a constant acceleration of (0, -9.8, 0). By disabling the physical simulation engine and setting a constant acceleration, a great deal of complexity can be avoided.
Another example is two objects that stick together and behave as a single entity. Though this can be simulated as a MultiBody object, if other aspects of physical simulation are not required, it may be better to enforce the relationship between the objects manually at each time-step by making one of the objects move itself to maintain a certain position relative to the other.
It's often unclear which technique should be used, but many users tend to err on the side of enabling physics which is the more complicated solution. True physical simulation is typically necessary only when dealing with physically realistic jointed bodies, such as a simulated robot or simulated animal. You should be aware of the pros and cons of true physical simulation and consider using your own "pseudo-physics" instead.
Enabling Physical Simulation
To write a simulation with physical simulation, your controller object should be a subclass of the class PhysicalControl. This class sets certain simulation parameters to values sensible for physical simulation, such as integration step, gravity, etc.
Physics must be enabled for Mobile objects on an object by object basis using the method enable-physics. When dealing with physical simulations, however, it is often preferable to use the Mobile subclass Link for which physical simulation is automatically enabled.
Fast Physical Simulation
The ODE simulation library supports an accelerated physics simulation which offers great improvements in simulation speed and memory usage, at the expense of some accuracy. The fast physics algorithm scales better than the normal physics algorithm as the number of interacting physical bodies increases. With a small number of interacting physical bodies, there may not be a great difference between the two. As the number increases, however, the benefits of fast physics will become much greater.
Fast physics may be enabled using the method enable-fast-physics. An additional iterations parameter can be set using the method set-fast-physics-iterations. The default value of 40 should give good results, but the number may be adjusted upwards for more accuracy, or downwards for better performance.
Writing Stable Physical Simulations
The physical simulation engine can be quite sensitive to the configuration of bodies in a simulation. This can lead to performance problems, instabilities and unexpected results. Because of the number of factors involved, it can be difficult to track down the exact reason for instabilities or unexpected results.
Below are some things to watch out for when dealing with physical simulation.
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Instabilities may arise when dealing with very large (heavy) and very small (light) objects
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Exerting very large joint pressures or velocities may cause unrealistic behaviors.
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Beware of joints which force invalid or conflicting conformations on your objects.
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Avoid forcing deep collisions between objects with either joints or manual movement.
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Use of redundant or unnecessary joints will cause instabilities and performance problems.
The Components of Physically Simulated Bodies
[Note] Changed in breve 2.0
The methods used for loading images have been changed from breve 1.x, so pay close attention to this section if you're updating your simulation from a previous version of breve.
In order to construct physically simulated agents, you'll need to be familiar with the components of physically simulated bodies. There are three main components used in physical simulations:
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Links, the basic building blocks of physically simulated objects
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MultiBodies, physical bodies made up of one or more Link objects ([link])
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Joints, rigid connections between Link objects ([link])
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Springs, flexible connections between Link objects ([link])
Dynamically Creating and Destroying Joints
breve allows Joints to be created and destroyed dynamically over the course of the simulation.
Joining MultiBodies dynamically is simple—you simply link them as always using the various Joint subclasses. The joints can be made not only to modify the structure of a single MultiBody, but also to join together distinct MultiBodies.
Breaking MultiBodies is accomplished using the Joint method break.
Prior to breve version 2.0, when all Links had to be part of a MultiBody to appear in the simulated world, breaking joints were often accompanied by broken hearts: breaking a joint could cause entire subtrees of links to disappear into the ether because the links were orphaned. In breve 2.0, links will go on living happily even if they are not associated with a MultiBody.
Even though it is incredibly useful, physical simulation can add complexity and potential instabilities to a simulation. This chapter begins with the section When to Use Physical Simulation ([link]), which discusses when it is appropriate to use physical simulation and possible alternatives to full physical simulation. You should read this section first to help you decide whether physical simulation is necessary for your simulation.
Using Terrains With Physical Simulation
The class Terrain allows fractal terrains to be created in breve. These terrains provide a more realistic ground than simply using a flat plane. The terrains can be automatically generated using the method generate, or set manually by the user using the method set-height. See the Terrain class documentation for information on using terrains.