| 摘要 |
<p>The present invention provides apparatus, systems and methods for fail passive servo controllers (104). In accordance with an exemplary embodiment of the present invention, servo controller (104) is used with an ALS to control an aircraft during landing procedures. In accordance with one aspect of this exemplary embodiment upon a failure (e.g., of one of the components of ALS) servo controller (104) fails passively rather than actively. In an exemplary embodiment, the fail passive nature of the servo unit (100) is accomplished by providing at least two independent signal and drive current path (214a, b) for controlling the servo motor (106). As such, the servo motor (106) with not generate torque unless the two independent signal lanes (214a, b) agree. For example, when a component such as processor (206), difference amplifier (204), or PWM (205a, b) fails or otherwise ceases to function properly, servo motor (106) will not runaway, but rather will fail with only minor transient movement, or alternatively, servo unit (100) will lock at its current position. In this manner, servo motor (106) will not generate a deviation from flight path or other significant control inputs until system monitors detect the fault and return control to the pilot.</p> |
