This
model shows a model of a car with
a transmission. A transmission is
generally used when an engine has
a relatively narrow band over which
the maximum power of the engine
is available. In order to obtain
high torque over a wider range of
speeds, the engine is connected
to a set of gears with different
size ratios (the transmission).
A car with a transmission is a classic
example of a hybrid system, since
the continuous dynamics of the car
depend on the current discrete state
of the transmission. An automatic
transmission can be viewed as a
feedback control system which takes
the current continuous and discrete
states of the system, in addition
to the throttle input from a driver,
and generates a signal which is
the current gear selection. Designing
a "good" transmission
that balances driver comfort (minimum
jerkiness) with performance (maximum
applied torque) over all parameters
(engine speed, vehicle speed, and
throttle) while incorporating practical
details (implementation limitations,
material wear) is a challenging
problem. The Block
Diagram for the model was constructed
using the VisualSim schematic editor
called ModelBuilder.
