An anchorless boat positioning system for establishing and maintaining a boat at a selected geographic location without the use of a conventional anchor. In one embodiment, a steerable thruster is used whose thrust and steering direction are determined and controlled on the basis of position information signals received from global positioning system (GPS) satellites, relative steering angle between the boat and the thruster and boat heading indication signals from a magnetic compass. The system continuously monitors the position and heading of the boat and compares it with the stored coordinates of the selected anchoring location(s) to generate control signals for the steerable motor. Several modes of operation are disclosed and Euler transformations for offset antenna placement for error reduction are taught. Proportional, integral, and derivative control (PID) of four constants of vessel control is also provided. Multiple thrusters in various arrangements are also provided to control either the orientation of the boat or a second point of interest on the boat at a second geographic location.
The present system is a system for controlling a trolling motor in a fishing boat. The system comprises a transmitting unit and a receiving unit. The transmitting unit includes a direction sensor, a selection switch, and a transmitter. The direction sensor automatically senses the direction to which the user desires to steer the fishing boat when the user points the direction sensor in that direction. The user then uses the selection switch, and by "clicking" the switch once the transmitter sends a signal with the direction information to the receiving unit. The receiving unit then receives the signal containing the direction information, and affects the trolling motor in such a way that it steers the fishing boat in the desired direction.
A circuit and associated method for determining the heading of a vehicle or device with a satellite ranging system receiver is provided. The circuit requires only a single front end RF stage. A single RF stage can be used because the incoming signal received at the first antenna is delayed with respect to the signal received at the second antenna and the two signals are merged together, to form a combined signal. The combined signal can be down converted and sampled in a single stage. The samples are then separately correlated to detect the data associated with the portion of the signal attributed to each antenna. The differences between the measured data are then used to calculate the relative orientation (heading and pitch) of the device upon which the two antennas are disposed.
A trolling motor control system includes plurality of modules that are connected to a communication bus to transmit and receive data used in controlling operation of a trolling motor. Based upon data transmitted over the bus, trolling motor speed, steering, and trim can be controlled. The modules can include motor controller modules, foot pedal modules, compass and GPS modules, RF modules for wireless control, battery metering modules, diagnostic modules, accessory device driver modules, power trim controller modules, and power steering controller modules.
A speedometer and communication device for boats includes a hand-held GPS unit, mounting member and antenna ring. The mounting member has a flange that extends and secures the mounting member to a cavity located in the dashboard of the boat. The mounting member may further have a power plug to supply power and mounting posts to secure the hand-held GPS unit. The antenna ring contains a receiver for receiving GPS signals and a transmitter for re-sending GPS signals. The hand-held GPS unit receives, calculates, and displays data relating to speed, location, time and includes user-selectable buttons for contacting emergency services.
A system and method for providing precision locations for sensors which make up an array of sensors in a gunshot detection system. In a preferred embodiment sensors employ a commercial GPS which reports a sensor position or a group of pseudoranges to GPS satellites. A server collects differential information from a differential node and, in one preferred embodiment, calculates a precision position for each sensor by adjusting the reported position or pseudoranges with the differential information. In another preferred embodiment differential information is sent from the host to individual sensors which calculate their own precision positions. Differential information may be latitude and longitude corrections, pseudorange corrections, ionospheric delay, GPS satellite clock drift, or other corrective term which will improve the accuracy of a sensor position.
