The application of a new nonlinear optimal control strategy to the station-keeping control of an underwater robotic vehicle is considered. The control approach described and demonstrated here is based upon the numerical approximation of solutions to the Hamilton-Jacobi-Bellman equation. These solutions are computed by an iterative application of a Galerkin-type method. Preliminary simulation re...

Geosynchronous orbit (GEO) is a very important strategic resource. In order to maximize the utilization of GEO resources, use all-electric propulsion platforms can greatly extend service life satellites. Therefore, this paper proposes control scheme north/south station keeping (NSSK) by using electric with manipulator. First, on basis traditional calculation method semi-diurnal period orbital i...

Small fixed-wing UAS that are able to hover combine the station keeping abilities of a rotary wing platform and the extended range of conventional aircraft. Current autopilots for these vehicles rely on inertial measurements plus airspeed to transition from forward flight to hover, accumulating appreciable position error during the transition. Once in hover, a combination of inertial and GPS da...

An autonomous dynamic positioning scheme for a novel triangular floating marine platform is developed, that stabilizes its linear and angular velocities as well as its position and orientation. For this platform, the required closed-loop forces and moments are provided by three rotating pump-jets, located at the bottom of three partly submerged cylinders, located at the corners of the platform....

Compact zero-mass pulsatile jet actuators are proposed for low-speed maneuvering and station keeping of small underwater vehicles. The flow field of such jets are initially dominated by vortex ring formation. Pinched-off vortices characterize the extremum impulse accumulated by the leading vortex ring in a vortex ring formation process. Relevant parameters in this process are identified in orde...

Stratospheric airship is capable of stationkeeping at high altitude in precondition of the balance of buoyancy and weight, thrust and drag. Based on specific computation process, when some hypotheses are given, the length of airship can be calculated and it is emphasized to analyze the impacts on payload capability performance and conceptual parameters (such as length, surface area and volume) ...

The Autonomous Formation Flight (AFF) project at the NASA Dryden Flight Research Center (Edwards, California) investigated performance benefits resulting from formation flight, such as reduced aerodynamic drag and fuel consumption. To obtain data on performance benefits, a trailing F/A-18 airplane flew within the wingtip-shed vortex of a leading F/A-18 airplane. The pilot of the trail airplane ...