We address the problem of state feedback translational motion control of a spacecraft formation through a modified sliding surface controller using variable gains and I action for disturbance rejection. The exponential varying gains ensure faster convergence of the state trajectories during attitude maneuver while keeping the gains small (and the system less stiff) for station keeping. Integral...

The inclusion of the linearized J2 effect in the Hill equations of relative motion gives greater insight into satellite formation flying dynamics, and the opportunity to investigate alternative feedback control strategies for the station keeping task. The work of Schweighart and Sedwick is verified and extended as time varying and analytical models are developed to incorporate the J2 perturbati...

This paper looks at the problem of reducing energy use robot movements in a station with stochastic execution times, while keeping productivity station. The is formulated as optimization problem, that constrains makespan to meet deadline high probability. function times operations, and goal reduce this by finding optimal operation order. A theoretical motivation why variables under some conditi...

This paper presents a control allocation method for simultaneous station-keeping and momentum management maneuvers. The considered satellite model is equipped with internal external actuators to the satellite’s orbit attitude and, concurrently, unload angular stored in reaction wheels. Our allocates achieve objectives. Internal such as wheels generate torque based on conservation of momentum. I...

A homography-based dynamic control approach applied to station keeping of autonomous underwater vehicles (AUVs) without relying on linear velocity measurements is proposed. The homography estimated from images a planar target scene captured by downward-looking camera directly used as feedback information. full dynamics the AUV are exploited in hierarchical design with inner and outer loop archi...

The influence of the natural perturbation force will cause eccentricity GEO satellite to produce a periodic motion with period years, and then east–west station oscillate. From perspective best fuel-saving or failure thruster used for keeping, some scholars have proposed method slightly deflecting thrust north–south keeping (NSSK) east west achieve integrated inclination longitude. disadvantage...

In this paper we present multiple antenna transmitter optimization (i.e., spatial pre-filtering) schemes that are based on linear transformations and transmit power optimization (keeping average transmit power conserved). We consider the downlink of a wireless system with multiple transmit antennas at the base station and a number of mobile terminals (i.e., users) each with a single receive ant...

We consider downlink OFDMA in which users are imposed with different proportional-rate constraints, and a base station would like to maximise user rate over subcarrier assignment (SA) and power allocation (PA). To attain the objective, we propose a chunk-based SA and low-complexity PA algorithms. Numerical results show that the proposed SA and PA can provide higher average minimum achievable ra...