When a cart of overhead crane suddenly stops, the cargo would swing for a while.
On the other hand, by operating a cart in a procedure of
the Full-Accelerate => Half-Decelerate => Half-Accelerate => Full-Decelerate,
the cargo would not swing when the cart stops.
Similarly, by operating a cart in a procedure of
the Half-Decelerate => Full-Accelerate => Full-Decelerate => Half-Accelerate,
the inverted pendulum would not swing when the cart stops.
This procedure can be obtained by converging the final solution of the state-space
to be zero, which is composed of cart position, cart velocity, pendulum angle
and cart driving force.
