Methods and apparatus to recover rotorcraft are disclosed. A disclosed example apparatus includes a rotor of a vehicle, a rotatable hub to support the rotor, and a rotor hook disposed on the rotor. The rotor hook has a groove to receive a recovery line. The rotor is to contact the recovery line when the vehicle is flown toward the recovery line.

Methods and apparatus to recover rotorcraft are disclosed. A disclosed example apparatus includes a rotor of a vehicle, a rotatable hub to support the rotor, and a rotor hook disposed on the rotor. The rotor hook has a groove to receive a recovery line. The rotor is to contact the recovery line when the vehicle is flown toward the recovery line.

Methods and apparatus to recover rotorcraft are disclosed. A disclosed example apparatus includes a rotor of a vehicle, a rotatable hub to support the rotor, and a rotor hook disposed on the rotor. The rotor hook has a groove to receive a recovery line. The rotor is to contact the recovery line when the vehicle is flown toward the recovery line.

Methods and apparatus to recover rotorcraft are disclosed. A disclosed example apparatus includes a rotor of a vehicle, a rotatable hub to support the rotor, and a rotor hook disposed on the rotor. The rotor hook has a groove to receive a recovery line. The rotor is to contact the recovery line when the vehicle is flown toward the recovery line.

A control system is described that is connected to an advanced arresting gear system. The control system has: (a) an outer control loop; (b) a first inner control loop associated with a port-side motor current controller for outputting a voltage command for controlling a port side motor that controls a port side of an arrestment cable; (c) a second inner control loop associated with a starboard-side motor current controller outputting a second voltage command for controlling a starboard side motor that controls the starboard side of the arrestment cable. Each of the port-side motor current controller and the starboard-side motor controller comprises: a positive sequence controller, at least one negative sequence controller, one or more delay state feedback to counter control loop delays, wherein the delay state feedback provides high bandwidth, low current overshoot, small current rise time and good current stability margins.

A control system is described that is connected to an advanced arresting gear system. The control system has: (a) an outer control loop; (b) a first inner control loop associated with a port-side motor current controller for outputting a voltage command for controlling a port side motor that controls a port side of an arrestment cable; (c) a second inner control loop associated with a starboard-side motor current controller outputting a second voltage command for controlling a starboard side motor that controls the starboard side of the arrestment cable. Each of the port-side motor current controller and the starboard-side motor controller comprises: a positive sequence controller, at least one negative sequence controller, one or more delay state feedback to counter control loop delays, wherein the delay state feedback provides high bandwidth, low current overshoot, small current rise time and good current stability margins.

Disclosed is a recovery device for unmanned aerial vehicles including a recovery pulley, a pulley rail and a damper, wherein the recovery pulley is used to be coupled for recovering unmanned aerial vehicles, and the pulley rail is used to carry the recovery pulley; the recovery pulley is connected to the pulley rail by rollers, and the damper is connected to the recovery pulley for generating a damping force for a linear movement of the recovery pulley. The recovery device for unmanned aerial vehicles of the present invention can be adapted to recover all types of aerial vehicles, has a simple structure, is easy to manufacture and has a low cost. Through the cooperation of the pulley rail, the recovery pulley and the damper, the recovery of the unmanned aerial vehicles of various weights can be performed. Through the foldable and retractable pulley rail, the recovery device is highly mobile. The present invention can have a wide range of application, and can be applied for comprehensive recovery in ships, vehicles, onboard situations, islands, forests and buildings.

A base attachment module (BAM) of a small aerial vehicle (SAV) for attaching the SAV to an unprepared work surface has a surface meeting docking assembly (DA) with contact points for contacting the work surface, and a contracting suction cup (CSC) in a position surrounded by the contact points such that it extends beyond a plane (or other surface contour) of the points in a fully extended operating position, and is retracted below the plane in a retracted position. Actuation of the CSC when in contact with the surface, allows for the DA to be brought into contact with the contact points in a controlled manner, for a high stiffness attachment, as is needed for deployment of robotic tasks from a SAV.

A system for monitoring tilled floor conditions within a field includes a sensor frame and a tilled floor sensing assembly supported on the sensor frame. The assembly, in turn, includes a plurality of pins configured to be extended relative to the sensor frame such that each pin penetrates a top surface of the field. Furthermore, the assembly includes a plurality of position sensors, with each position sensor configured to capture data indicative of a position of a given pin of the plurality of pins relative to the sensor frame. Moreover, the assembly includes a plurality of force sensors, with each force sensor configured to capture data indicative of a force being applied to a given pin of the plurality of pins. Additionally, the data captured by the plurality of position sensors and the data captured by the plurality of force sensors is indicative of a tilled floor profile of the field.

A retractable runway edge sheave for use in an aircraft arresting system. The arresting system functions to extend a cable across a runway for capture by a tailhook of an aircraft. The retractable runway edge sheave is designed to raise and lower the cable. The disclosed system may also feature a ramping system.