
Chapter 8
Examples
8.1 Introduction
In this chapter we illustr ate the use of results presented in the preceding
chapters to determine optimal controls and optimal trajectories.
8.2 The Rocket Car
A car, which we take to be a point mass, is pr opelled by rocket thrusts along
a linear track endowed with coordinates. Units are assumed to be normalized
so that the equation of motion is ¨x = u, whe re u is the thrust force constrained
to satisfy −1 ≤ u ≤ 1. Initially the car is at a point x
0
with velocity y
0
. The
problem is to determine a thrust program u that brings the car to rest a t the
origin in minimum time.
If we consider the state of the system to