Abstract: An outboard computer system which combines the outputs from onboard course, performance and wind measuring instruments to determine a sailing vessel's instantaneous rate of progress to windward when beating. This information is then used to produce audible and/or visual signals indicating to the crew when the optimal track and sail setting for the conditions has been attained, enabling them to beat optimally under the current ambient conditions. The system is also used to control automatically the settings of each of the sailing variables: rudder, main sheet, traveller, jib sheet, etc. in order to sail the vessel optimally when beating without the intervention of the helmsman or crew. A facility is also provided for recording the instantaneous rate of progress to windward in coincidence with any other variables of interest for the purpose of post evaluation and assessment of a variety of boat related equipment and procedures. The system also provides displays relating to wind history and wind prognosis.

Abstract: A heading change unit for a ship's autopilot gyrocompass that provides a heading error signal to produce a proportional rudder control signal. An operator enters a heading change which causes an up/down counter to be incremented or decremented in accordance with the heading change order. The counter is also responsive to a step heading input signal. The count is referenced to a zero value and converted to an analog control signal by a digital-to-analog converter. As the ship turns towards the new heading, the changing step heading input will cause the counter to count back to zero. The displayed amount of heading error or ordered heading change is generated by converting the analog heading error signal to a digital encoded format which controls a display. The heading error signal is generated in the form of a parallel twelve bit binary code which represents integer degree changes and 1/6 degree fractional changes.

Abstract: A vessel wave heading control apparatus is disclosed for use on a floating vessel. Linear acceleration signals from two accelerometers, which sense the rotational acceleration of the vessel due to waves which impact the vessel from a particular direction, are processed by a computer which subsequently produces vessel heading change signals to the steering and propulsion means of the vessel. These signals indicate the required heading and required rate of change of vessel heading necessary to turn the vessel into the direction of the oncoming waves in a timely manner.

Abstract: The present invention relates to an automobile pilot system employing an electronic navigation receiver such as a Loran C receiver and an azimuth detector such as a magnetic compass. The automatic pilot system is capable of coping with undesirable forces to move a moving body laterally due to current flows and the wind, thereby directing the moving body to a destination point preset.

Abstract: An automatic trim control system designed to be used on power boats equipped with electric or hydraulic actuated trim tabs is disclosed. The unit senses out of trim conditions in two planes (pitch and roll) and transmits control signals to the electro-mechanical control lines to reposition the trim tab attitudes, thereby reestablishing preset trim conditions as required.

Abstract: When the right turn or left turn is set by operating one joystick lever, the bow thrustor arranged on the bow side generates the drift thrust in the rightward or leftward direction in accordance with the turning angular velocity on the basis of the operation of the joystick lever. At the same time, the propellers provided on the stern side are controlled so as to generate the backward thrust proportional to the absolute value of the turning angular velocity of the ship. The forward thrust of the ship which is caused due to the generation of the drift thrust by the bow thrustor is suppressed. Thus, the ship is turned to the right or left around the stern as a rotational center at a predetermined speed with the position of the hull held.

Abstract: There is disclosed a portable system to control and monitor the basic maneuvering functions of marine vessels: The control and monitoring functions are contained on a hand held, small and lightweight consul which can be plugged into multi-pin sockets which are wired from various remote places of the ship to a central electronics logic and control module matrix. Switches on the portable helm control the electronic module matrix which powers servo motors mechanically linked to: engines' throttle controls, shift forward-neutral-reverse controls, and steering apparatus. Feedback loops monitor the positions of these maneuvering functions. Monitored on the portable helm are: rudder angle, engines' idle status, forward, neutral and reverse status of each drive trian, power on, and engines' synchronization.

Abstract: An adaptive autopilot for Marine Vessles which seeks to obtain minimum combined hull and rudder drag while maintaining heading control by providing optimum rudder activity through a series of iterative steps.

Abstract: An automatic control system for a craft having a steering wheel connection for manual guidance of the craft, an automatic pilot sensing system connection, and a drive shaft connection for driving the craft's steerage mechanism. The automatic control system is provided with sensing signals for correction of heading by well-known auto pilot. The steering wheel is removed from the drive shaft and the automatic control system is easily installed between the drive shaft and the steering wheel. The automatic control system provides a steering shaft adaptor which provides the drive and mounting element to the craft's steering mechanism without modification to any existing components in the craft.

Abstract: A stabilization aid for a vehicle- or vessel-borne search unit comprises two servomechanisms for stabilizing the observation part (3) of the search unit about two mutually perpendicular axes (S.sub.1 and S.sub.2) mounted on the part of the search unit which rotates about the search axis (1). The stabilization aid comprises a computer (7) for determining, from the instantaneous angle of inclination (.alpha.) of the platform (2) supporting the search unit with respect to an earth-fixed reference axis and the instantaneous angular position (B) of the search unit about the search axis (1), measured in the plane of the platform (2), input signals for the servomechanisms. A portion of these input signals are compensating signals for the control errors in the servomechanisms.

Abstract: A control system for controlling the rotation of a rotary mechanism such as a propeller housing in a Z-type propulsion apparatus is provided. A command signal and a feedback signal both relating to the rotation of the rotary mechanism are compared with each other. And a control signal which varies at a predetermined inclination is generated when the command and feedback signals differ in amplitude from each other. And a drive unit rotates the rotary mechanism in accordance with the control signal.

Abstract: An electronic boat controller which can be plugged in and removed from a boat which is hard wired to a plurality of locations which when plugged into allows the boat controller to become electrically wired to power controllers which supply power on a pulse basis to electric motors from a common power supply. This power supply is an electric battery mounted at the rear of the boat. The controller controls two channels which control ultimately two power supplies to two separate and distinct electric motors which are spacially separated at the rear of the motor permitting turning as well as forward control of the boat.

Abstract: Described herein is a steering amplifier for use in the steering systems of watercraft. Potentiometers are mounted within the helm unit and the feedback unit of the craft and these potentiometers are used to determine the various helm and rudder positions. Circuitry is provided to determine the difference or error between the helm position and the rudder position and to energize solenoid valves which cause the rudder to move in the appropriate direction to correct the error.

Abstract: Improved navigational apparatus which interfaces between a Loran C receiver and a ship's auto pilot is disclosed. Output information from the Loran receiver is taken from a standard NMEA jack and is input to the inventive apparatus. Steer and steer correction signals output from the inventive apparatus are input to the auto pilot. The receiver's serial output data is converted to a parallel output and temporarily stored or held by a data latch. A timer releases the data to a logic circuit which supplies steer correction signals to the auto pilot. The timer, in conjunction with the logic circuit, inputs the steer signals at predetermined time spaced intervals to prevent circling of the ship. A data subtractor in conjunction with the timer reduces the ship's rate of return to the predetermined course setting.

Abstract: An error sensing system for use in marine autopilot systems of the type having a photographic film compass disk aligned with the direction North and sensing means associated with the disk is operative to sense relative movement between the disk and the sensors in response to changes in the heading of the vessel. A first direction error surface portion on the disk has opaque and transparent areas defining a zero reference therebetween, a second magnitude error surface portion on the disk has a second zero reference position in predetermined relation to the first zero reference position and an area of variable transparency extending along the second surface portion. The first and second surface portions are defined by images along the peripheral surface of the photographic film disk.

Abstract: Apparatus for steering a vessel and maintaining it on a preset course through the combination and arrangement of an incremental encoder and a heading reference circuit is disclosed. The encoder includes circuitry operative to generate a directional signal and count pulse for each incremental movement of the vessel away from the preset heading and for transmitting same into a heading reference circuit. Counting means are included in the heading reference circuit including adjustable reference setting means to set the counter at a reference position corresponding to the preset heading. The counter is responsive to the pulses received from the incremental encoder to count in a positive or negative direction under the control of the directional signals. A sign-detector in the counter detects whether the total number of pulses is positive or negative with respect to the reference position and generates a signal representative of the direction of the net change.

Abstract: An automatic trim circuit for hydrofoil craft which compensates for offsets in the system due to manufacturing and assembly tolerances and wear of parts. This is achieved by integrating an error signal derived by comparison of a reference signal with an actual position signal and applying the integrated output, after amplification, to one or more servo systems which actuate the control surfaces of the hydrofoil craft.

Abstract: A reversible motor is coupled to the stern leg of a watercraft for angulating the leg up and down through a trim and tilt range. A manually settable device provides a voltage signal corresponding to the desired trim angle and a position sensor provides a voltage signal corresponding to the present stern leg position. A first comparator changes the state of its output if the difference between the signals has one polarity and a second comparator changes state for the opposite polarity. The state changes turn on one of two transistor switches which provide an up or a down signal, respectively, to a motor control circuit for causing the motor to run until the difference is nulled. When the active transistor switch turns off, the other delivers a momentary pulse for plugging the motor.

Abstract: An apparatus for providing the operator of a marine vessel with an alarm when when a malfunction occurs in the steering system of the vessel. The apparatus utilizes a closed loop simulator to simulate the rudder position, and a comparison of the simulated rudder position to the actual rudder activates the alarm when a predetermined threshold value has been exceeded. Appropriate time delays during which the alarm is disabled make the apparatus adaptable for use with steering systems having a steering gear which has rate inconstancy, and a shaping circuit makes the apparatus adaptable for use with steering systems having a steering gear which has static positional nonlinearity.

Abstract: The present invention relates to an automatic steering apparatus for ships which prevents the occurrence of directional instability due to unusual phenomena which occur at small rudder angles of so-called full-bodied ships.When the rudder angle of such ship is small, two stable steady turning conditions occur so that the turning movement cannot assume any single state and it results in a frequent and irregular unstable ship motion.

Abstract: In an auto-steering system for boats and cruisers having, in each of the starboard and port motor drivers, a comparator and a motor driver circuit in series with each other. The level of the reference voltage to be applied to the comparator is adjusted in accordance with changes in the environmental conditions during sailing of the boat in order to selectively raise or lower the control accuracy of the system and, when further required, the drive circuit takes the form of a lowpass filter of a selected time constant so that the system is made irresponsive to the so-called chattering deviation of the boat sailing course. Not only great saving in the power consumption but also remarkable reduction in malfunction of the mechanical and electrical parts while assuring macroscopic following of the boat along the prescribed navigation course.

Abstract: A system for controlling the course of a vessel. A digital computer 22 receives information signals from a geographic position locator 20, such as a Loran-C receiver, a depth sounder, or a water temperature sensor, and is also capable of interactive communcations with a remote terminal 24 which is accessible by an operator of the vessel. The digital computer 22 continuously monitors the information signals and develops therefrom a digital output signal representing the sign and magnitude of vessel cross-track error. To obtain information required to determine cross-track error, and to obtain certain other information relating to the identity and type of the geographic position locator 20, the digital computer 22 transmits questions to the remote terminal 24 for display therby and evaluates responses made by the operator through remote terminal 24. The digital computer 22 may be enabled or disabled in response to instructions from the operator using remote terminal 24.

Abstract: A rudder control circuit for an automatic steering system of the type which includes a known sensor circuit and a reference input circuit selectively connected thereto for easy zero-point calibration separate from the normal control operation is disclosed. The control circuit also includes a high impedance indicator circuit connected to the main feedback line of the control circuit for visual indication of rudder angles with minimized disturbance on the feedback control. The control circuit is further advantageously accompanied by a remote steering unit including a manually adjustable and automatically resettable manual steering circuit for easy steering by single operator.

Abstract: An automatic takeoff control system for hydrofoil craft characterized in that the control surfaces of the craft are caused to automatically assume predetermined positions during takeoff, obviating the necessity for special levers, lever settings and special operator procedures which were involved in making a transition from hull-borne to foil-borne operation in accordance with prior art techniques.

Abstract: Apparatus for automatically steering a boat having a wheel-operated steering mechanism including a detachable motor-driven actuator arm engaging the spokes of the wheel. The actuator arm is connected through a clutch to a servo mechanism for driving the actuator. The servo mechanism is responsive to a heading set on a magnetometer or a preset apparent wind indication. The heading responsive circuitry includes an integrating loop to compensate for long-term changes in steering conditions.

Abstract: A control system for a hydrofoil characterized in that a transition from the foil-borne to the hull-borne mode of operation is initiated and the craft caused to descend or land automatically due to a failure in the primary power source for the control system or some other off-normal condition. The invention constitutes an improvement in prior art systems of this type in that, should the primary power source fail, an auxiliary gyroscope automatically provides stabilization about the roll axis to the unstable craft. This causes the craft to maintain an essentially level deck attitude or, should the craft be in a turn, to roll out of an inclined deck attitude toward a level deck attitude as the craft descends to the hull-borne mode of operation subsequent to primary power source failure. In this manner, the severity of impact with the water as the craft descends during a turning maneuver is reduced.

Abstract: A protective system is provided for water-jet propulsion systems in which water entering through an intake port is discharged in a jet by a pump. Unloading and overspeed of the pump prime mover may occur if the intake comes out of the water and this is prevented by a system which senses the water pressure in the pump inlet and responds to the pressure and the rate of change of pressure to prevent overspeed of the prime mover by setting it to idling speed. When the pressure and rate of change indicate that the intake is again submerged, the prime mover is reset to normal operating control.

Abstract: An improved steering control system is provided for improving the handling qualities of hydrofoil craft during takeoff. In steering control systems for hydrofoils, the craft is banked by operation of control surfaces and the rudder is turned in the corresponding direction to coordinate the turn. To improve the handling qualities and maneuverability during the period of acceleration from hull-borne to foil-borne operation, the steering control system is modified during this period by decreasing the gain of the control loop for the control surfaces and by increasing the gain of the control loop for the rudder. A lag filter is also introduced into both loops.

Abstract: In order to automatically position a ship which is subjected to external disturbance forces and which is provided with propulsion units arranged to orient the ship in the direction of the resultant of such disturbance forces, there is derived a representation of a control value from the sum of the representations of the actual transverse forces acting on the ship, the control value representation is compared with a representation of a given nominal value, and the control value is brought to zero on the basis of the result of such comparison.

Abstract: An autopilot automatically adjusts the sensitivity of a ship's steering system to accommodate changes in speed as well as sea and wind conditions. The autopilot utilizes heading error, speed and speed squared signals to produce a rudder order signal for controlling rudder position. The rudder order signal is developed in a heading keeping circuit unless a heading change greater than a predetermined threshold is commanded, in which event a programmer substitutes a heading change circuit for the heading keeping circuit. The sensitivity of the heading change circuit is automatically adjusted as an inverse function of vessel speed squared, and automatic rudder order limits are established in the same circuit as an inverse function of speed. The sensitivity of the heading keeping circuit is adjusted in accordance with a signal from an automatic gain control circuit which derives a performance index J from ship's speed, heading error and rudder order signals occurring during a given measurement interval.

Abstract: The invention provides a method and device for producing substantially kinematic steering of a vessel in a yaw path having a given radius of curvature conforming with a predetermined control law. During the steady state phase of the yaw when there exist conditions for dealing with an easily controllable radius of curvature and in the vessel is steered by rudder deflection changes and by utilizing servo control methods in such a way that the radius of curvature of the vessel, which has been determined by instrument facilities aboard the vessel, follows a predetermined suitable program for the yaw curvature during the yaw.

Abstract: A marine auto pilot employing a compass with a Hall-effect sensing element in conjunction with a magnetic circuit designed to provide a high intensity magnetic field; electrical circuitry designed to produce high servo-loop gain at frequencies lower than the normal sea wave frequencies, and lower gain at the normal sea wave frequencies; a D.C. Linear Motor drive system in conjunction with a rudder position feedback signal; and a linear ball-screw and nut gearing system for converting the high-speed output of the direct current drive motor to a low-speed high-torque drive at the rudder, having the nut and ball-screw connected through rolling contact balls.

Abstract: Apparatus for detecting malfunctions in rudder-type steering systems utilizes electrical order and rudder angle signals. The rudder-order signal is applied to a closed-loop simulator that includes integrating apparatus adjusted to provide a time-variant simulated rudder angle signal which varies in the same manner that the actual rudder angle signal would vary in the absence of a malfunction when exposed to the same rudder error signal. The simulated and actual rudder angle signals are compared in a summing amplifier whose output is applied to a thresholding circuit which actuates an alarm whenever the instantaneous values of the simulated and actual rudder angle signals differ by more than a predetermined amount.

Abstract: An automatic pilot for a sailboat includes a mode switching arrangement which permits a person to operate the sailboat in any one of several modes. One is the STEER mode, a second is the OFF mode, a third is the STANDBY mode, a fourth is the WIND mode and a fifth is the COMPASS mode. Another switching arrangement enables either the WIND mode or COMPASS mode to be operated in COURSE CHANGE sub-mode manners. Various mechanisms and circuitry further are included to enable the sailboat to be manually steered, to stabilize the rate of change of rudder position, to null a control that is a function of the change in heading error, to wash out certain signals under certain conditions, to inhibit certain signals under certain conditions, and to provide a steering command that furnishes a visual direction to the steersman when the automatic pilot is in a COURSE CHANGE sub-mode.

Abstract: An automatic piloting system for the automatic steering of a marine or other vessel along an intended course in which a digital signal representing an intended course is processed to provide rudder commands for steering the desired course.

Abstract: A maneuvering control system particularly for use in controlling a vehicle such as a submarine or surface craft, which utilizes both manual and automatic control. Electrical signals in accordance with the manipulation of a manual control device are generated by means of a synchro transmitter and fed to a synchro differential transmitter. Automatic control signals generated in an automatic control signal generator are converted to a mechanical form by a synchro follower which provides a mechanical input to the differential transmitter. Adjustable limit stops are provided for the synchro follower output shaft to limit the automatic signal input to the differential transmitter, thereby preventing an "out-of-control" condition in the event of a malfunction in the automatic control signal generator. The output of the differential transmitter which represents the algebraic sum of the manual and automatic inputs is used to drive a synchro control transformer, which in turn drives a servo amplifier.

Abstract: A drilling unit is disclosed which incorporates a submersible streamlined hull supporting a streamlined upper hull above the surface of the water by support columns and trusses. The unit is directionally controlled by transverse thrusters and in-line propulsion screws in the submersible hull which are operated by a control system to maintain station keeping over the wellhead at an optimum heading for minimizing the effects of environmental forces such as wind, current and wave action. The control system senses the vessel's heading and surge and sway motions with respect to the wellhead reference and converts this information into error signals. The bow and stern thrusters and in-line propulsion screws are then operated to produce thrust forces which reduce the respective errors. In response to the generation of a stern thrust the control system iteratively calculates a change in the bow target point position on the target circle which will make the stern thrust trend toward zero.

Abstract: The measured rolling rate of a ship and a measured liquid level difference in a liquid contained in a stabilizing tank are supplied to frequency dependent members having identical frequency response to obtain a derived roll angle and derived level difference after which a circuit is provided to measure the phase difference between the quantities developed and to develop an output analog voltage representing the difference between a desired relationship between the phases of the two and the actual phase relationship.

Abstract: A control system for hydrofoil craft is one in which control surfaces are moved automatically in response to signals derived from the motion of the craft to stabilize and control the craft. In such systems, a potentially dangerous condition can occur in case of a failure or malfunction in the roll control system. In order to prevent such conditions, two roll sensing devices are provided which normally generate identical signals to actuate the control surfaces to stabilize the rolling motion. In case a failure or malfunction, the signals provided by the two sensing devices become different and apparatus is provided to compare these signals and to respond to a difference in the signals to initiate landing of the craft rapidly and safely.

Abstract: An automatic steering system for vessels, operational in a manual mode to select a desired heading, and in an automatic mode to maintain the selected heading. In the manual mode, a magnetic compass incorporated in a servo loop is maintained at a null position to continually monitor the vessel heading. When the system is switched to the automatic mode, the compass servo loop is deactivated and a control loop activated. The control loop keeps the compass output at null by maintaining the vessel on the selected heading. Automatic course corrections are accomplished by turning the helm an amount proportional to a deviation signal, and immediately returning the helm to its original position less a small preset angle. A wireless remote control unit affords the capability of remotely steering the vessel, selecting a new course, and switching between automatic and manual modes.

Abstract: A servo-system for controlling position as well as rate of movement of a controlled device. Any command signals are processed or shaped prior to comparison with the feedback position signals. This processing includes integration at one of two available integration rates in accordance with the magnitude of the difference between the command and shaped command signals to correct for synchro non-linearities. The processing also includes limiting the input to the integrator such that the velocity as well as position of the controlled member is controlled.A fail-detect system monitors critical signals and power levels and distinctively indicates a failure if any is detected.

Abstract: A marine steering arrangement wherein each of the starboard steering switch and port steering switch connected to a power source is closed upon receipt of an actuating signal resulting from a difference between an order signal of a rudder angle and an actual signal of a rudder angle, so as to conduct power to a rudder driving mechanism, rotating the rudder to the order rudder angle position within an allowable extent of the rudder angle, is provided with an improvement which further comprises at least one limit switch for shutting off the power source to stop any further rotation of the rudder beyond either of the rudder angle limits.

Abstract: A guidance system for controlling the path of a boat comprising a first conductor disposed below the surface of water in a first elongated loop and connecting at the terminals thereof across an A.C. source of electrical signal and a second conductor driven in a quadrature with the first conductor and disposed in a second loop partly superposed over the first loop. A first and second orthogonal inductive coil, mounted in the boat along a plane parallel to the loop and a plane normal to the loop plane and substantially parallel to the centerline thereof sense the vertical and horizontal components of the electromagnetic field generated about the conductor loops to produce corresponding induced signals respectively varying in amplitude and phase according to the amplitude of the electromagnetic field and the position thereof.

Abstract: A process and apparatus for stabilizing the course angle of a large ship by producing a signal when the measured variation of the course angle with time reaches an extreme value and utilizing said signal to reset the rudder over a discrete angle towards starboard if the said extreme value is in the starboard direction and towards port in the opposite case.

Abstract: An improved marine compass employs a Hall-effect device which provides an output signal related to the relative rotation of the compass card therein. When the Hall-effect device is mounted on a course dial whose position with respect to the compass' lubber line indicates a desired course, the output signal may be used as an input to an autopilot system. The system includes a DC constant current supply for the Hall-effect device, and an integrated circuit operational amplifier for amplifying said output signal to provide an angle signal having a usable level. A differentiator including a second IC operational amplifier provides a rate signal from the angle signal. A rudder signal is provided by a rudder position sensor employing a second Hall-effect device and a third IC operational amplifier.