Why is the motion plat form needed?
It is nothing to say that when you carry out a driving simulation by Virtual
Reality (VR), the closer driver's sense approaches to the reality, the
more accurate simulation results can be acquired. As a human have five
senses: Sight, Hearing, Taste, Smell and Touch, reflecting all of senses
including Balance to the simulation is not easy at all. The most important
sense is Sight in driving, which is reproduced by 3D VR simulation. As
for the Hearing, sound system can be done. Not using Taste and Smell, drivers
need Balance to capture a vehicle motion. Now, the cutting-edge technology,
Motion Plat Form have been established to allow drivers communicate The
Motion Plat Form is not so important when you aim to the simple training,
in which vehicle motion don't change widely.
Basic of Motion Reproduction
To reproduce drivers' awareness for movements, it's necessary to trick
human senses. The balance can be integrated from some information sources.
A 3D accelerator can be sensed with semicircular canals (anterior / posterior
/ lateral semicircular canal) and horizontal and vertical accelerator can
be done with an otolith (utricle and saccule). This was just capture 3D
movement, so 3D movement has to be reproduced by the Motion Plat Form.
To support these movement including rotation and straight movement completely,
6 degrees of freedom (6DOF): 2 times 3 axes is 6 DOF, is needed. But, because
the Motion Plat Form work in a more limited space than realistic vehicle
space, it's impossible to reproduce real vehicle motion. It primarily detects
acceleration, not capturing by the amount of movement or speed. Thus the
Motion Plat Form is created to reproduce the acceleration and controlled.
As the way of reproducing the motion, following technologies are used.
General 6 DOF hardware configurations are combined with multiple actuators
under a cockpit. With this configuration, the cockpit moves and rotates
from the center point to all directions. The maximum lengths of the movement
from the center point equals to the limit of motion, so continuous and
long-time movements are impossible.
| Terms guide
|| 6DOF Platform
Three measurements are adopted for this limitation.
In case of large simulator, moving 6DOF hardware on horizontal rail using
X and Y table improve horizontal long acceleration.
- Reproduce the high frequency acceleration of vehicle primarily
- To reproduce the next acceleration, the cockpit moves back to the center
with the speed which drivers can't realize.
- Reproduce the horizontal acceleration by gravity, when you lean the cockpit
Above these ways, Surge and Sway can be reproduced with the Motion Plat
Form of 3DOF.
Also, rotating the cockpit horizontally with Yaw table reproduce the realistic
feeling when you make the curve.
UC-win/Road allows you to link with the Motion Plat Form, a hardware OEMed
by INNOSIMULATION, Inc as an option of the UC-win/Road Drive Simulation.
To realize to link with the one, it was needed to improve software. To
reproduce a high performance motion, we adopted vehicle motion model of
INNOSIMULATION, Inc and the Washout filer which control platform behavior.
a vehicle motion model with CarSim by Mechanical Simulation Corporation
is also available. To prevent uncontinuous motion of plat form, the location
of plat form is controlled with over the rate of 100Hz. Calculation of
vehicle motion and control of plat form can reproduce continuous motion,
In addition, for the safety of hardware and user, four layers safety system
- Filter not to exceed the movable range and the safety acceleration for
the command signal of plat form outputted from UC-win/Road.
- Check the move command signal for the same purpose on the hardware device
side whether the signal works well or not.
- Check the signal which is sent to actuator itself, and if actuator have
problems, actuator's motion can be forced to stop.
- Emergency stop button is available whenever you want to use it.