| 摘要 |
<p>A vehicle (10) pulls an implement (14) attached to a hitch (12) with a lift cylinder (24) actuating a rockshaft (22) to control implement working depth. A servo system (50) responds to a position command signal from an operator control (30), a signal from a control (34) selecting position or draft control mode, a position feedback signal from a sensor (28) and draft load feedback signals from load sensors (16). The servo system (50) provides a control signal to an electrode hydraulic valve (26) controlling the cylinder (24) and periodically superimposes a squarewave disturbance signal. The response thereto is analysed by the servo system to determine a gain characteristic of the soil/implement system and a gain factor influencing the control signal is adjusted in inverse relationship so that overall gain remains substantially constant.</p> |
