The disclosure provides an electric quad vehicle, a control system, and method of operation. The electric quad vehicle may include a central hub and four legs, each pivotably mounted to the central hub, each leg including an electric motor rotatably coupled to a wheel. Each leg may include a joint allowing the leg to bend to a retracted state with the wheel adjacent the central hub. The electric quad vehicle may include handle bars extending from the central hub including rider controls of acceleration and steering. The electric quad vehicle may include a control system configured to translate rider input to the rider controls into control signals for each of the electric motors.

A ground maintenance vehicle that includes: front steering wheels; rear drive wheels; a frame with a first and second pivot point; a single lever steering assembly with a single lever steering control, where the single lever steering assembly is coupled to the first pivot point; multi-axis articulating joint coupled to the second pivot point; a front caster steering assembly coupled to the multi-axis articulating joint; and where the front caster steering assembly and the multi-axis articulating joint simultaneously provide articulating and caster steering proportional to lateral movement from the single lever steering control.

Crawl operations for four-wheel steering vehicles are described herein. An example vehicle described herein includes four wheels, a front steering actuator to turn the front wheels, a rear steering actuator to turn the rear wheels, a front drive motor to drive the front wheels, and a rear drive motor to drive the rear wheels. The vehicle also includes an electronic control unit (ECU) to activate the front steering actuator to turn the front wheels in a first direction, activate the rear steering actuator to turn the rear wheels in a second direction opposite the first direction such that the front wheels and the rear wheels are turned in opposite directions, activate the front drive motor to drive the front wheels in a reverse direction, and activate the rear drive motor to drive the rear wheels in a forward direction while the front wheels are driven in the reverse direction.

A system to simultaneously adjust a wheel track axle width and a steering angle of an agricultural vehicle made of: an at least two variable axle assemblies, each one of the variable axle assemblies connected to a wheel set of the agricultural vehicle is provided. During the wheel track axle adjustment process of a variable wheel track axle machine the angle of each wheel is “toed-in” or toed-our depending on wheel track extension or retraction. When the wheel track axle of the machine is being extended, all wheels are commanded to “toe-out” 3 degrees to aid in the extension and reduce external forces on the wheel and axle system. When the wheel track axle of the machine is being retracted, all wheels are commanded to “toe-out” 3 degrees to aid in the retraction and reduce external forces on the wheel and axle system. Once the wheel track axle adjustment is complete all wheels return to 0 degrees for normal operation.

A steering system for controlling an agricultural machine having a pair of front wheels and a pair of rear wheels includes a controller, an operator steer input for communicating a steer command, a steer input sensor for detecting and outputting the steer command to the controller, a primary differential steering system for operably controlling the pair of front wheels, and a secondary steering system for operably controlling the pair of rear wheels. The secondary steering system includes a first actuator for controlling a first rear wheel and a second actuator for controlling a second rear wheel. The primary differential steering system is controlled based on the steer command. The controller outputs a control signal to operably actuate the first and second actuators at a non-linear steering gain rate as a function of the steer command.

A steering system for controlling an agricultural machine having a pair of front and rear wheels includes a controller and a steer input sensor for detecting a change in an operator steer input corresponding to a steer command. The system includes a displacement input for communicating a motor displacement associated with an operating mode. A primary differential steering system includes a drive motor for operably controlling the pair of front wheels and a secondary steering system controls the pair of rear wheels. The controller determines if the motor displacement is being controlled according to a first motor displacement or a second motor displacement, and outputs a control signal to actuate first and second actuators as a function of the steer command. The control signal includes a rear steering gain that is a function of machine speed and either the first motor displacement or the second motor displacement.

An unmanned aerial vehicle (UAV) autonomously perching on a curved surface from a starting position is provided. The UAV includes: a 3D depth camera configured to capture and output 3D point clouds of scenes from the UAV including the curved surface; a 2D LIDAR system configured to capture and output 2D slices of the scenes; and a control circuit. The control circuit is configured to: control the depth camera and the LIDAR system to capture the 3D point clouds and the 2D slices, respectively, of the scenes; input the captured 3D point clouds from the depth camera and the captured 2D slices from the LIDAR system; autonomously detect and localize the curved surface using the captured 3D point clouds and 2D slices; and autonomously direct the UAV from the starting position to a landing position on the curved surface based on the autonomous detection and localization of the curved surface.

A hydraulic system for controlling a pair of steerable caster wheels includes a left steering command valve, a right steering command valve, and a rear steering control valve. A supply pressure fluid circuit interconnects a pressure source and the rear steering control valve. A command valve supply fluid circuit interconnects the rear steering control valve with both the right steering command valve and the left steering command valve. A left side steering fluid circuit interconnects a left side actuator and the left steering command valve. A right side steering fluid circuit interconnects a right side actuator and the right steering command valve. A fluidic tie rod fluid circuit interconnects both the left side actuator and the right side actuator with the rear steering control valve. A tank return fluid circuit interconnects the rear steering control valve, the left and right steering command valves, and a tank.

The disclosure proposes a method for ascertaining and/or monitoring a mechanical state of at least one tie rod apparatus of an electrically assisted steering system of a vehicle, wherein at least one operating characteristic variable, which is correlated to a steering movement, of at least one steering actuator and/or of at least one steering controller of the steering system is ascertained and evaluated for ascertaining and/or for monitoring the mechanical state of the tie rod apparatus.

A method for controlling a hydraulic servo steering system in a vehicle includes reading out a collision warning signal to establish that a collision assistance case exists, and in response to determining that the collision assistance case exists, providing a hydraulic fluid by a hydraulic pump of the servo steering system. Serving for steering assistance has an actual volumetric flow-rate that is greater than or equal to a minimum volumetric flow-rate. The method additionally includes increasing a pump speed if the actual volumetric flow-rate is less than the minimum volumetric flow-rate, the pump speed being dependent on an engine/motor speed of a drive engine/motor interacting with the hydraulic pump.