| 1. |
|
|
| 2. |
- D’Amico, Simone, et al.
(författare)
-
Spaceborne autonomous formation-flying experiment on the PRISMA mission
- 2012
-
Ingår i: Journal of Guidance Control and Dynamics. - : American Institute of Aeronautics and Astronautics (AIAA). - 0731-5090 .- 1533-3884. ; 35:3, s. 834-850
-
Tidskriftsartikel (refereegranskat)abstract
- The Prototype Research Instruments and Space Mission Technology Advancement (PRISMA) represents the first European technology demonstration of formation-flying and on-orbit-servicing techniques. Several hardware and software experiments, either at subsystem or system levels, have been successfully conducted since the launch of the dual-satellite mission in June 2010. This paper describes the guidance, navigation, and control functionalities and presents key flight results from the so-called Spaceborne Autonomous Formation-Flying Experiment (SAFE) executed in September 2010 and March 2011 as one of the primary PRISMA mission objectives. SAFE is intended to demonstrate autonomous acquisition, keeping, and reconfiguration of passive relative orbits for advanced remotesensing and rendezvous applications. As shown in the paper, the onboard Global Positioning System navigation system provides relative orbit information in real time with an accuracy better than 10 cm and 1 mm/s (three-dimensional, root mean square) in position and velocity, respectively. The impulsive formation control achieves accuracies better than 10 m (three-dimensional, root mean square) for separations below 2 km with minimum usage of thrusters, ensuring high predictability for simplified mission operations and minimum collision risk for increased safety.
|
|
| 3. |
- Felicetti, Leonard, 1982-, et al.
(författare)
-
Attitude Stability and Altitude Control of a Variable-Geometry Earth-Orbiting Solar Sail
- 2016
-
Ingår i: Journal of Guidance Control and Dynamics. - 0731-5090 .- 1533-3884. ; 39:9, s. 2112-2126
-
Tidskriftsartikel (refereegranskat)abstract
- A variable-geometry solar sail for on-orbit altitude control is investigated. It is shown that, by adjusting the effective area of the sail at favorable times, it is possible to influence the length of the semimajor axis over an extended period of time. This solution can be implemented by adopting a spinning quasi-rhombic pyramidal solar sail that provides the heliostability needed to maintain a passive sun-pointing attitude and the freedom to modify the shape of the sail at any time. In particular, this paper investigates the variable-geometry concept through both theoretical and numerical analyses. Stability bounds on the sail design are calculated by means of a first-order analysis, producing conditions on the opening angles of the sail, while gravity gradient torques and solar eclipses are introduced to test the robustness of the concept. The concept targets equatorial orbits above approximately 5000km. Numerical results characterize the expected performance, leading to (for example) an increase of 2200km/yr for a small device at geostationary Earth orbit.
|
|
| 4. |
- Felicetti, Leonard, 1982-, et al.
(författare)
-
Vision-Aided Attitude Control for Space Debris Detection
- 2018
-
Ingår i: Journal of Guidance Control and Dynamics. - : American Institute of Aeronautics and Astronautics. - 0731-5090 .- 1533-3884. ; 41:2, s. 566-574
-
Tidskriftsartikel (refereegranskat)
|
|
| 5. |
- Gärdsback, Mattias, et al.
(författare)
-
Deployment Control of Spinning Space Webs
- 2009
-
Ingår i: Journal of Guidance Control and Dynamics. - : American Institute of Aeronautics and Astronautics (AIAA). - 0731-5090 .- 1533-3884. ; 32:1, s. 40-50
-
Tidskriftsartikel (refereegranskat)abstract
- Space webs are lightweight cable nets deployable in space to serve as platforms for very large structures. Deployment and stabilization of large space webs by spin have gained interest because the rotational inertia forces are in the plane of rotation and the spin rate that determines the magnitude of the web tension can be chosen to meet the mission requirements. Nevertheless, a robust control method is required for a successful spin deployment. The control law used for the deployment of the Znamya-2 membrane reflector, for which a feedback-controlled torque is applied to the center hub, was applied here to a quadratic space web folded in arms coiled around the hub. To analyze the deployment, an analytical three-degree-of-freedom model and a fully three-dimensional finite element model were developed. The simulations indicate that it is favorable to deploy the web in just one step. It is also suggested that the simple analytical model can be used to determine important mission requirements such as the torque, power, and energy required for different deployment times.
|
|
| 6. |
- Gärdsback, Mattias, et al.
(författare)
-
Optimal Deployment Control of Spinning Space Webs and Membranes
- 2009
-
Ingår i: Journal of Guidance Control and Dynamics. - : American Institute of Aeronautics and Astronautics (AIAA). - 0731-5090 .- 1533-3884. ; 32:5, s. 1519-1530
-
Tidskriftsartikel (refereegranskat)abstract
- Future solar sail and solar power satellite missions will consider using centrifugal forces for deployment and stabilization. Some of the main advantages with spin deployment are that the significant forces are in the plane of rotation, and a relatively simple control can be used and the tension in the membrane or web can be adjusted by the spin rate. Existing control strategies seem to either consume excessive energy or cause oscillations. In this study, control laws are derived from the solution to relevant optimal control problems and existing controls. The derived control laws are used in deployment simulations with both simple analytical three-degree-of-freedom models and a fully-three-dimensional finite element model. The results indicate that the derived control laws can be used to minimize the energy consumption and oscillations as for an optimal control, yet retain the simplicity of previous control laws.
|
|
| 7. |
- Härkegård, Ola, 1973-
(författare)
-
Dynamic Control Allocation using Constrained Quadratic Programming
- 2004
-
Ingår i: Journal of Guidance Control and Dynamics. - : American Institute of Aeronautics and Astronautics. - 0731-5090 .- 1533-3884. ; 27:6, s. 1028-1034
-
Tidskriftsartikel (refereegranskat)abstract
- Control allocation deals with the problem of distributing a given control demand among an available set of actuators. Most existing methods are static in the sense that the resulting control distribution depends only on the current control demand. In this paper we propose a method for dynamic control allocation, in which the resulting control distribution also depends on the distribution in the previous sampling instant. The method extends regular quadratic-programming control allocation by also penalizing the actuator rates. This leads to a frequency-dependent control distribution, which can be designed to, for example, account for different actuator bandwidths. The control allocation problem is posed as a constrained quadratic program, which provides automatic redistribution of the control effort when one actuator saturates in position or in rate. When no saturations occur, the resulting control distribution coincides with the control demand fed through a linear filter.
|
|
| 8. |
- Oravec, Juraj, et al.
(författare)
-
Computationally Tractable Formulations for Optimal Path Planning with Interception of Targets Neighborhoods
- 2017
-
Ingår i: Journal of Guidance Control and Dynamics. - : AMER INST AERONAUTICS ASTRONAUTICS. - 0731-5090 .- 1533-3884. ; 40:5, s. 1221-1230
-
Tidskriftsartikel (refereegranskat)abstract
- Devising the planar routes of minimal length that are required to pass through predefined neighborhoods of target points plays an important role in reducing the missions operating cost. Two versions of the problem are considered. The first one assumes that the ordering of the targets is fixed a priori. In such a case, the optimal route is devised by solving a convex optimization problem formulated either as a second-order cone program or as a sum-of-squares optimization problem. Additional route properties, such as continuity and minimal curvature, are considered as well. The second version allows the ordering of the targets to be optimized to further reduce the route length. We show that such a problem can be solved by introducing additional binary variables, which allows the route to be designed using off-the-shelf mixed-integer solvers. A case study that shows that the proposed strategy is computationally tractable is presented.
|
|
| 9. |
- Pons, Arion, 1995, et al.
(författare)
-
Multi-Axis Nose-Pointing-and-Shooting in a Biomimetic Morphing-Wing Aircraft
- 2023
-
Ingår i: Journal of Guidance, Control, and Dynamics. - 1533-3884 .- 0731-5090. ; 46:3, s. 499-517
-
Tidskriftsartikel (refereegranskat)abstract
- Modern high-performance combat aircraft exceed conventional flight-envelope limits on maneuverability through the use of thrust vectoring, and so achieve supermaneuverability. With ongoing development of biomimetic unmanned aerial vehicles (UAVs), the potential for supermaneuverability through biomimetic mechanisms becomes apparent. So far, this potential has not been well studied: biomimetic UAVs have not yet been shown to be capable of any forms of classical supermaneuverability, as are available to thrust-vectored aircraft. Here we show this capability, by demonstrating how biomimetic morphing-wing UAVs can perform sophisticated slow-timescale nose-pointing-and-shooting (NPAS). Nonlinear flight-dynamics analysis is used to characterize the extent and stability of the multidimensional space of aircraft trim states that arises from biomimetic morphing. Navigating this trim space provides an effective model-based guidance strategy for generating open-loop NPAS maneuvers in simulation. Our results demonstrate the capability of biomimetic aircraft for air combat-relevant supermaneuverability, and provide strategies for the exploration, characterization, and guidance of further forms of classical and nonclassical supermaneuverability in such aircraft.
|
|
| 10. |
- Santoni, Fabio, et al.
(författare)
-
Attitude dynamics and control of drag-balance CubeSats
- 2013
-
Ingår i: Journal of Guidance Control and Dynamics. - : American Institute of Aeronautics and Astronautics (AIAA). - 0731-5090 .- 1533-3884. ; 36:6, s. 1834-1839
-
Tidskriftsartikel (refereegranskat)abstract
- The article examines the system stability, obtaining upper bounds for the mass unbalance to verify the applicability of magnetic control laws valid for rigid bodies to the drag-balance CubeSat two-body system. The rod is connected to the satellite body by two flexural springs. The spin axis is orthogonal to the rod, exposing the plates to the incoming atmosphere flux at the spin rate and generating a relative displacement between the DBI and the satellite. The spin frequency component of this displacement is therefore related to the atmospheric drag force and can be evaluated by measuring the displacement itself and isolating the spin frequency content. Single-, double-, and triple-unit CubeSat implementations of the DBI concept are possible. The drag-balance CubeSat attitude control system must provide for attitude acquisition, spin axis orbit normal pointing, spin rate estimation, and regulation.
|
|
