The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 23, 1996
Filed:
Oct. 11, 1994
Douglas W Ford, Newport, OR (US);
Eric K Juve, Newport, OR (US);
Nautamatic Marine Systems, Newport, OR (US);
Abstract
An automatic steering system (10) has a control subsystem (14) that employs a yaw rate control loop (90) and a steering control loop (92) to drive a hydraulic subsystem (12) in which the deflection rate of a steering actuator (16) is controlled without need for either a steering actuator angle sensor or an electronic steering bias integrator. Rather, the control subsystem employs a proportional rate servosystem to control the steering actuator deflection rate and a double-acting hydraulic cylinder (34) to provide the steering bias integral action. The control subsystem employs an electric compass (96) to generate heading data that are stored in a heading command register (102). A heading error is formed by calculating a difference between a desired heading and the current heading. A rate taker (94) generates a yaw rate feedback signal by differentiating changes in the current heading. The heading error and yaw rate feedback signal are processed to generate a steering rate command to which the steering control loop responds by pumping hydraulic fluid at a rate proportional to the steering rate command into the hydraulic cylinder to deflect the steering actuator of an outboard motor (18).