2.4. INTEGRATED SUSPENSION TILTING SYSTEM 13
Cabin
Cabi
n
4
Controller
M M
C
ontroller
M M
(a) (b)
Figure 2.6: ISTS in (a) tilting mode and (b) height adjustment mode.
environments [34]. All these functionalities could be adopted for NTV applications with the
proposed system.
Although the idea of an integrated suspension tilting system is presented, the detailed
design of the actuation and sensing modules are open for implementations [10]. An example is
illustrated in Figure 2.7. e major components are: a fixed displacement pump which can rotate
in either direction; a solenoid valve which can disconnect the pump from hydraulic pipelines and
eliminates the need for a motor brake; a flow meter to measure the volume of the hydraulic fluid
being pumped into the cylinder; and a displacement sensor to monitor the strut movement.
A typical workflow of the ISTS can be described as follows. When a tilting or height ad-
justment requirement is determined by the vehicle controller, the solenoid valve is first energized,
and the fluid will be pumped into the cylinders to drive the piston to the desired position [10].
e process is monitored by the on-board sensing system. Once the desired strut position is
achieved, the solenoid valve will be closed. In that state, cylinders and accumulators, along with
the connection pipelines, form the hydraulic interconnected suspension (HIS) [31] for passive
roll stiffness enhancements.