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guidance, flight mechanics and trajectory optimization

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I. -.<br />

In order to give an appreciation for the need for more sophisticated tech-<br />

niques, a sample problem will be worked by the Dynamic Programming techniques<br />

which have been discussed. The presentation will serve two purposes: first,<br />

it will illustrate the use of Dynamic Programming on a multi-dimensional<br />

allocation problem <strong>and</strong>, second,- it will demonstrate the rapid growth of<br />

storage requirements as a function of the dimension of the problem. The<br />

method of approximation in policy space will then be discussed in order to<br />

illustrate the savings in storage requirements <strong>and</strong> the increase in computa-<br />

tion time.<br />

Consider the problem of minimizing the function<br />

subject to the constraint that<br />

<strong>and</strong><br />

(2.3.4)<br />

z, + x2 + x3 = 3 (2.3.5)<br />

VJ + fi + $5 = 3 (2.3.6)<br />

Obviously, using Dynamic Programming to find a solution to this problem is<br />

not very efficient. The method of Lagrange multipliers is by far a more<br />

suitable method. However, the Dynamic Programming solution will be shobm<br />

for illustrative purposes.<br />

First, the problem i.s reduced to a series of simpler problem.<br />

53<br />

(2.3.7)<br />

(2.3.8)<br />

(2.3.9)

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