英語(yǔ)翻譯
While using the simulator,the operator sees the
container moving in a virtual world.The virtual
world combined with the motion platform,which
creates movement effects,gives the operator real
world-like feedback.The surrounding sounds give
the final touch to the simulator environment.Besides
the visual feedback,the feedback from the motion
platform is very important in operator training.If
the operator does not feel the accelerations of the
machine system caused by control manoeuvres,the
training may cause operating behaviour that is toofast and harsh as swift operation movements seem
not to cause any physical feedback.When motion
platform feedback is added,the operating behaviour
becomes smoother,because discontinuous control
signals usually cause accelerations unpleasant to
operator.
Basically real-time simulators consist of a user
interface,an I/O-system,a real-time simulation
model describing the dynamics of the machine in
question,a visualization of the environment,and a
possible motion platform producing acceleration
effects for the operator.Figure 2 presents the components
required to build a real-time training
simulator.
Control signals given by the operator are transferred
via the I/O-interface into the dynamic simulation
model.In simulation models,signals can be
treated in several different ways.Simple binary on/
off-signals can be used to launch operation cycles
such as opening or closing the container locking.
Analogue signals can be used to give reference
values for more complicated functions.The
rotational velocity reference of an electric drive is
a good example of the use of analogue signals.
During the study,it became clear that the most
natural way to treat analogue control signals is to
use them as a reference for the calculation of external
forces acting in the system.This way,control signals
seldom cause discontinuities,as the change in force
causes change in system accelerations,which are
integrated twice to solve the position information
of the system.
The position information of separate parts is transferred
into the visualization system,where the virtual
world is drawn.In this case,also the surrounding
sound is controlled by the dynamic model.Sounds
related to different events,such as collisions,the
use of motors,and so on,are played on the basis of
event information gathered from the simulation
model.The information of accelerations affecting
the operator is used in calculating reference values
for the motion platform.An inverse kinematic
model of the motion platform is required to map
the operator’s acceleration information from the
global coordinates to actuator positions and
velocities.