The forced pendulum system senses the centrifugal force of its own by a gyro set to the head car and tilts a body by a hydraulic cylinder or the like. Though the system has an advantage that a large tilt angle can be obtained, it has disadvantages that it is difficult to control the head car and the pendulum function is lost if a control mechanism gets out of order. The system is used mainly in European countries.
3) Natural pendulum system with control
The natural pendulum system with control is a system peculiar to Japan, which is obtained by improving the problems of the natural pendulum system and forced pendulum system.
Figure 4.2-2 shows the working theory of the natural pendulum system with control in which the shapes and positions of curves of all lines are stored in a memory on a car and a proper tilt timing and a proper tilt angle are given to each curve in accordance with the stored information.
However, an error occurs between stored curve position and actual curve position as the traveling distance of a train increases. Therefore, it is necessary to set a wayside element in a station premise every 5 to 7 km and correct the error by supplying positional information to a passing car.
This system has an advantage that sudden deterioration of the riding comfortableness can be avoided because the system returns to the natural pendulum system even if a control mechanism gets out of order.
