Abstract: A line acquisition system predicts and displays an acquisition path to reduce the uncertainty surrounding the path taken by a vehicle when acquiring a destination path. The line acquisition system calculates the drivable acquisition path based on the current states of the vehicle, such as position, speed, heading, and curvature. The line acquisition system continually updates and displays the acquisition path as the vehicle is manually steered by the user. When the user engages a steering controller, the last calculated acquisition path is used to automatically steer the vehicle onto the destination path. Displaying the acquisition path allows the user to observe, prior to automatic steering engagement, the path the vehicle would take from its current state to the destination. The user can then decide whether the predicted acquisition path will interfere with terrain or obstacles that the user wishes to avoid.

Abstract: A method for estimation of relative coordinates between two parts of a linked vehicle system. The system includes a towing vehicle and a towed implement or trailer. A first sensor is configured to measure the movement rate of the towing vehicle while a second sensor is configured to measure the movement rate of the towed implement. Both sensors interact with each other to measure the absolute distance between sensors. Using the known linkage geometry, relative distance between the sensors and relative rotation rates, the relative coordinates between the towing vehicle and towed implement can be estimated.

Abstract: A line acquisition system predicts and displays an acquisition path to reduce the uncertainty surrounding the path taken by a vehicle when acquiring a destination path. The line acquisition system calculates the drivable acquisition path based on the current states of the vehicle, such as position, speed, heading, and curvature. The line acquisition system continually updates and displays the acquisition path as the vehicle is manually steered by the user. When the user engages a steering controller, the last calculated acquisition path is used to automatically steer the vehicle onto the destination path. Displaying the acquisition path allows the user to observe, prior to automatic steering engagement, the path the vehicle would take from its current state to the destination. The user can then decide whether the predicted acquisition path will interfere with terrain or obstacles that the user wishes to avoid.

Abstract: A line acquisition system generates a curvature profile based on initial vehicle states (starting position, heading, curvature and speed), vehicle steering capabilities (calibrated vehicle curvature and curvature rate limits), and initial vehicle position errors relative to the destination path. The curvature profile describes changes in vehicle curvature over a path distance from a current position to a destination path. The line acquisition system constructs an acquisition path from a combination of clothoid, circular arc, and straight lines corresponding with different segments of the curvature profile. The acquisition path can be displayed on a user interface allowing a vehicle operator to observe, prior to automatic steering engagement, the path the vehicle would take from a current state to the destination path.

Abstract: A calibration scheme measures roll, pitch, and yaw and other speeds and accelerations during a series of vehicle maneuvers. Based on the measurements, the calibration scheme calculates inertial sensor misalignments. The calibration scheme also calculates offsets of the inertial sensors and GPS antennas from a vehicle control point. The calibration scheme can also estimate other calibration parameters, such as minimum vehicle radii and nearest orthogonal orientation. Automated sensor calibration reduces the amount of operator input used when calibrating sensor parameters. Automatic sensor calibration also allows the operator to install an electronic control unit (ECU) in any convenient orientation (roll, pitch and yaw), removing the need for the ECU to be installed in a restrictive orthogonal configuration. The calibration scheme may remove dependencies on a heading filter and steering interfaces by calculating sensor parameters based on raw sensor measurements taken during the vehicle maneuvers.

Abstract: A navigation system aids a driver of a collection vehicle in keeping pace and distance with a lead harvester while collecting grain. The navigation system can be used for any leader-follower vehicle drive formation. A navigation system steers the head vehicle based on a continuously known position and attitude. Navigation data for the lead vehicle is broadcast to a following collection vehicle. A navigation system in the following vehicle processes the lead vehicle navigation data to determine a relative position and attitude. The navigation system in the following vehicle generates steering and speed commands based on the relative position and attitude to automatically drive to a designated target position alongside the lead vehicle. In one example, an artificial oscillation is induced into the target position to more evenly distribute material in the following vehicle.

Abstract: A guidance system identifies a path on a field and then calculates a position and heading of a trailer relative to the path. The guidance system steers a vehicle connected to the trailer based on the calculated trailer position and heading to minimize the trailer positional error and more quickly and accurately align the trailer with the path. The guidance system may align the trailer with the path while steering the vehicle in a reverse direction and may steer the vehicle based on a predicted trailer position and heading.

Abstract: A guidance system may derive a K-turn path when a vehicle reaches an end of a first way line in a field. The guidance system may send the K-turn path to a steering controller to turn the vehicle around in a headland area to the beginning of a second way-line in the field. A first segment of the K-turn path may turn the vehicle along a first path in a forward direction and a second segment of the K-turn path may turn the vehicle along a second path in a reverse direction. A third segment of the K-turn path may turn the vehicle along a third path in the forward direction to a starting location of the second way-line. The K-turn path uses less area than other types of turns reducing the amount of headland used for turning around the vehicle.