The Conversion of a General Motors Cadillac SRX to Drive-By-Wire Status

For the past 25 years, by-wire systems have been used in the most advanced flying machines known to man. In the 1960s, McDonnell Douglas, now The Boeing Company produced the F-15 Strike Eagle, a magnificent fighter jet with fly-by-wire capability. Fly-by-wire is where each mechanism is controlled electronically. The mechanical linkages are removed and every movement is communicated through electric signals alone. The idea of fly-by-wire forever changed the concept that a mechanical linkage has to initiate movement (i.e. pitch, roll, and yaw) of a vehicle. The use of electronic motors to control movement has proven to be more responsive and a more efficient use of space and energy. The responsiveness of the fly-by-wire system is one of the heralding accomplishments that make the F-15 such an engineering accomplishment which can fly at 2.5 Mach speeds. Thus the by-wire control is now setting the stage for better, faster vehicles in the air and on land.

By-wire systems are a means for quick communication between the driver and the components that control the vehicle. Every action that a vehicle can make (i.e. turning, accelerating, braking) is controlled via an actuator or motor. Each motor is controlled by an electronic signal via some form of human-vehicle interface (i.e. a steering wheel, a brake pedal or throttle pedal). In the F-15, a control stick serves as the controller for all maneuvers. All flaps, the air brake, and even the landing gear are controlled by hydraulic actuators. In previous jets, the controls surfaces (ailerons, flaps, air brake, etc.) were actuated through the hydraulic system, which were directly linked to the pedals and joystick. Now though, instead of using mechanical linkages to control the hydraulics directly, an electronic actuator controls the hydraulics via an electronic signal from the joystick. Before by-wire technology, flying an aircraft was a labor-intensive task. Flying inherently is a system which can become unstable if the pilot does not stay in control of the vehicle during all maneuvers. By taking out the mechanical linkages and reducing the weight of the aircraft, pilots can therefore concentrate on military operations instead of physically actuating the control surfaces.

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