Automatic control for trim tabs

An apparatus to adjust the position of a marine transportation system including a boat having a drive, a trimmable port tab and a trimmable starboard tab, the apparatus comprising:

• means for generating a boat speed signal indicative of a boat speed;
• means for generating a roll angle signal indicative of a roll angle through which the boat tilts during rolling;
• means for generating a yaw angle signal indicative of a yaw angle through which the boat turns during yawing;
• controller means operable in response to said boat speed signal, roll angle signal and yaw angle signal to generate an output signal distinguishing one boat operating condition from another;
• and
• tab trimming means operable in response to said output signal of said controller means to position the port and starboard tabs.

An apparatus to adjust the position of a marine transportation system including a boat having a drive, a trimmable port tab and a trimmable starboard tab, the apparatus comprising:

• means for generating a boat speed signal indicative of a boat speed;
• means for generating a roll angle signal indicative of a roll angle through which the boat tilts during rolling;
• means for generating a yaw angle signal indicative of a yaw angle through which the boat turns during yawing;
• means for generating tab position signals indicative of positions of the port and starboard tabs;
• controller means operable in response to said boat speed signal, roll angle signal, yaw angle signal and tab position signals to generate an output signal;
• and
• tab trimming means operable in response to said output signal of said controller means to position the port and starboad tabs.

An apparatus to adjust the position of a marine transportation system including a boat having a drive, a trimmable port tab and a trimmable starboard tab, the apparatus comprising:

• controller means operable to generate an output signal in response to varying boat operating condition;
• tab trimming means operable in response to said output signal of said controller means to position the port and starboad tabs;
• means for generating a boat speed signal indicative of boat speed;
• means for generating a rolling angle signal indicative of a roll angle through which the boat tilts during rolling;
• means for generating a yaw angle signal indicative of a yaw angle through which the boat turns during yawing;
• and
• means for generating tab position signals indicative of positions of the port and starboard tabs,
• said controller means being operable in response to said boat speed signal and yaw angle signal to distinguish one boat operating condition from another and operable in response to said roll angle signal and said tab position signals to generate said output signal.

An apparatus to adjust the position of a marine transportation system including a boat having a drive, a trimmable port tab and a trimmable starboard tab, the apparatus comprising:

• contoller means operable to generate an output signal in response to varying boat operating condition;
• tab trimming means operable in response to said output signal of said controller means to position the port and starboad tabs.
• means for generating a boat speed signal indicative of a boat speed;
• means for generating a roll angle signal indicative of a roll angle through which the boat tilts during rolling;
• means for generating a yaw angle signal indicative of a yaw angle through which the boat turns during yawing;
• and
• means for generating tab position signals indicative of acutal positions of the port and starboard tabs,
• said controller means being operable to read said yaw angle signal and to compare the latest yaw angle reading with the prior reading to determine a yaw angle rate,
• said controller means being operable to read said boat speed signal;
• said controller means being operable in response to said determined yaw angle rate and the lastest boat speed reading to distinguish one boat operating condition from another,
• said controller means being operable to read said roll angle signal and to compute an average of the latest roll angle reading and the prior readings to provide said average as a heel angle,
• said controller means being operable to compare said heel angle with a target heel angle to determine an error therebetween,
• said controller means being operable in response to boat operating condition and in response to said determined error to provide a tab target position command, and
• said controller means being operable in response to said tab target position command and said tab position signals to provide tab control signals as said output of said controller means.

A method of adjusting the position of a marine transportation system including a boat having a drive, a trimmable port tab and a trimmable starboard tab, the method comprising the steps of:

• monitoring the operation of the marine transportation system to provide an output distinguishing boat operation in an on-plane condition and boat operation in an off-plane condition;
• monitoring the operation of the marine transportation system to provide an output distinguishing boat travel in a straight forward condition and boat travel in a turning condition;
• monitoring the operation of the marine transportation system to provide an output distinguishing boat operation in a first heel condition in which the boat tilts to port and boat operation in a second heel condition in which the boat tilts to starboard;
• and
• positioning the port tab at a desired position and the starboard tab at a desired position in response to said outputs.