Moving-mass Control System Research Articles

Adaptive robust list control for an aircraft with a moving mass

The article is devoted to the development of a high-precision list angle control algorithm for an aircraft with a single moving mass. Taking into account the nonmodulated uncertainty and parametric uncertainties in the system, an adaptive robust control algorithm based on the backstepping scheme is proposed. The algorithm consists of robust and adaptive structures. The robust structure levels out nonmodulated uncertainties and disturbances in the system, while the adaptive structure estimates the system parameters. The proposed controller theoretically guarantees a global limited tracking capability according to the Lyapunov analysis method. The simulation results, confirming the effectiveness of the proposed algorithm are presented. Keywords adaptive robust control; backstepping; moving mass control system; maneuvering reentry vehicle

Attitude maneuver of a satellite using movable masses

This paper investigates the attitude maneuver problem of a spacecraft containing internal movable masses with zero angular momentum. The spacecraft dynamics in one dimension is first studied using the proposed moving mass control system with predefined mass motion. Next, a small-angle attitude maneuver method based on the sliding mode control technique is designed to accomplish the reorientation when the required maneuver angle is within the control capability of single-direction movable mass motion. Furthermore, a novel mass-shifting procedure is proposed for achieving full-domain attitude reorientation. The procedure includes a rest-to-rest maneuver method together with the trajectory optimization. Which, the rest-to-rest maneuver takes advantage of the attitude difference caused by sequential mass motion and the trajectory optimization is carried out based on time sub-optimal motion planning methods. The procedure is next combined with the small-angle maneuver method to achieve a high precision reorientation. Finally, numerical simulation results show that high precision full-domain attitude reorientation can be realized using the proposed control system with three internal movable masses.

Roll control for single moving-mass actuated fixed-trim reentry vehicle considering full state constraints

Moving-mass control system applies internal movable mass elements as actuators to shift the center of mass of the vehicle relative to the external aerodynamic forces to generate control torques. Although moving-mass control system provides sufficient control authority, it suffers from its nature of nonlinear and high-coupling. What's more, the design of the moving-mass control system confronts state constraints arising from two aspects: (1) physical limitation: the internal space of the vehicle is limited and the moving-mass element can not translate out of the shell; (2) performance requirements: limiting the maximum velocity of the moving-mass element can decrease the disturbances exerting on the vehicle significantly. Based on the purpose of controlling the roll attitude of a moving-mass actuated vehicle without violating any state constraint, we design a controller using integral barrier Lyapunov functionals to control the system and keep all the states bounded in the meanwhile. The backstepping procedure is adopted and the dynamic surface control scheme is applied to avoid the 'terms explosion' in that procedure. An adaptive law is proposed to diminish the influences caused by uncertainties whose boundaries are unknown. The performance of the proposed controller is illustrated by numerical simulations under various conditions.

Novel Moving Mass Flight Vehicle and Its Equivalent Experiment

This paper presents a novel configuration of flight vehicle with moving mass control. We focus on the development of the proposed control mechanism and investigate the feasibility of an equivalent experimental setup. First, the effect of the moving mass parameters on the control authority is investigated. Then, a control law based on immersion and invariance (I&I) theory is presented for the moving mass control system. In the design process, we select a first-order target system to reduce the difficulty of controller design. To deal with the coupling caused by the additional inertia moment, which is generated by the motion of the moving mass, the extended state observer (ESO) is designed. The proposed adaptive controller is simulated and tested on the experimental setup. Finally, the simulation results validate the quality of the proposed adaptive controller, which ensures a good performance in the novel configuration with internal moving mass.

Moving mass control system in conjunction with brain emotional learning-based intelligent control for rate regulation of suborbital reentry payloads

An adaptive intelligent control strategy based on a brain emotional learning model is investigated in the application of the rate regulation of suborbital reentry payloads. Because of nonlinear time-varying dynamics of these payloads, choosing an appropriate control mechanism and stability strategy can be an engineering challenge. Thus in a new approach, a moving mass control system in conjunction with brain emotional learning-based intelligent control is used to fulfill payload de-tumbling. The contribution of brain emotional learning-based intelligent control in handling the nonlinear time-varying dynamics is shown by comparison with results obtained from a linear proportional–integral controller. The results demonstrate excellent performance of brain emotional learning-based intelligent control in learning dynamic couplings and improvement of behavior without any considerable control system complexity.

Modeling and Variable Structure Control of Autonomous Underwater Vehicles with Moving Mass

In order to solve the problem of general fins and rudders being lower at low moving speed, the moving mass technical is applied onto AUV, thus to radically solve the weakness of control method with fin and rudder. The space dynamics model of moving mass control is created for AUV. And based on this, the moving mass control system is designed with the sliding mode variable structure control method so as to ensure system tracking error zero convergence. By controlling the moving mass movement with moving mass control system, the attitude of AVU is previously controlled. And simulation result proves that moving mass control system will control the AUV attitude angle precisely and rapidly.

RBF Neural Network-Based Terminal Sliding Mode Control for Reentry Warhead

The existing moving mass control system of a nonspinning reentry warhead could not drive the system error to reach zero in finite time. In order to settle the finite time reach issue, an RBF neural network-based terminal sliding mode controller was presented to design the moving mass control system. It used a terminal sliding mode to ensure that the error reaches zero in finite time. The disturbance and coupled terms of the warhead were treated as uncertainties. An RBF neural network was used to estimate the uncertainties. A nonspinning warhead was taken in the simulation to test the performance of the presented controller. The simulation results show the presented controller has faster tracking speed and higher tracking precision than the former research result.