guidance, flight mechanics and trajectory optimization
guidance, flight mechanics and trajectory optimization
guidance, flight mechanics and trajectory optimization
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the measurement errors could bdd to the fuel cost but under these<br />
conditions would not hinder the eventually successful rendezvous.<br />
The motion analysis in this monograph (Section 2.1) will not go<br />
beyond that of linear terms in the relative coordinates, since these<br />
terms are believed to be adequate for the ranges of relative motions<br />
to be considered. A brief discussion of the possible effects of<br />
perturbations due to air drag, earth oblateness, <strong>and</strong> solar-lunar<br />
gravitation is included in the last portion of Section 2.1.<br />
C. The <strong>trajectory</strong> control problem - Having determined the future course<br />
<strong>and</strong> set up the capability of determining the velocity requirements to<br />
effect rendezvous, a philosophy <strong>and</strong> a procedure to obtain it must be<br />
generated, described, <strong>and</strong> shown to be successful. This development<br />
of the <strong>guidance</strong> scheme is the heart of the problem. Thus, a series<br />
of techniques which have been suggested for this purpose are described<br />
in Section 2.2 (Guidance Equations). The rendezvous which is effected<br />
with any given <strong>guidance</strong> scheme, however, may not be as close as<br />
desired because of errors in the data <strong>and</strong> in the engine performance.<br />
Further, rendezvous will not be optimal unless allowance is made for<br />
the stochastic nature of the problem. Optimization techniques <strong>and</strong><br />
data filtering procedures will thus be important phases of the prob-<br />
lem, <strong>and</strong> these will be described as found in the literature in<br />
Sections 2.3 <strong>and</strong> 2.4, respectively.<br />
For evaluation of the various schemes <strong>and</strong> for assistance in choosing<br />
the state determination process, error analyses are required. The<br />
work that is available in this area will be described in Section 2.4<br />
Finally, in Section 3 suggestions for choosing the specific approaches<br />
for a number of types of systems <strong>and</strong> the definition of interface<br />
problems associated with mid-course orbital transfer or with the<br />
final docking will be discussed.<br />
3