System Scope
The Smart Air Management System is designed for this application to maintain a predetermined vehicle
ride height automatically and provides a means to manually lower or raise the ride height and exhaust and
fill the tag axle through a customized user interface. The system provides for side to side height control
as well as front to back control. The system also contains a feature to determine if the vehicle is on a
surface that will enable the chassis to be leveled within vehicle mechanical parameters. A visual
indication is also provided to determine mode selection and system malfunction detection.
System Definition
The Smart Air Management System (SAMS) contains four vehicle height sensors, a pneumatic manifold
assembly, an electronic control unit (ECU), the necessary wire harnessing, a pushbutton control user
interface, and the necessary vehicle interface hardware to provide the defined modes of operation and
system functionality. The user interface contains the required pushbuttons to allow the vehicle operator to
raise and lower the vehicle manually, exhaust and fill the tag axle manually, enable a self-leveling feature
to level the vehicle when parked on an uneven surface, and contains LED’s (light emitting diodes) to
provide a visual indication to the vehicle operator of the manual mode status, as well as system error
detection. The location and mounting of the user interface will be on the left side of the driver seat, on
the main operator control counsel. The angle sensors will be mounted on the vehicle frame in a 4-point
configuration: rear (2); front (2). The wire harnessing will provide the necessary connections for
providing DC electrical control power and ground to the SAMS system (from a suitable vehicle power
source), provide the necessary height sensor connectors, provide the pneumatic manifold wiring interface,
provide the necessary color coded wires for vehicle hardware integration, and provide the electrical
connections for the user interface. Functionally, the system will provide the following modes of
operation, i.e.
normal, raised, lowered, tag dump,
and
self-leveling
. This information is further defined in
the following sections.
Normal Mode
This mode of operation occurs automatically when the vehicle is operated at speeds of 20MPH and above.
It requires no further interaction by the vehicle operator. The ECU monitors the feedback signals from
the height sensors during normal vehicle operation. Should any of the four signals dictate that the vehicle
is above or below the programmed ride height; the ECU will energize the necessary manifold valve coils
to either fill or exhaust the respective air bag(s) to bring the vehicle back to the correct vehicle ride height.
The system will stay in this mode of operation unless conditions are satisfied to enter the other modes of
operation, as defined in the following sections.
Important: When towing, jacking, or raising the vehicle for service, the white harness plug,
located near the manifold assembly must be disconnected. This will prevent the SAMS system from
operating and eliminating the potential for unexpected suspension movement that may cause
damage to the vehicle or personal injury.
