An Attitude Control Strategy Using Four Cold Gas Thrusters for the SCRAMSPACE 1 Experiment

2012 ◽  
Author(s):  
Michael Creagh ◽  
Paul A. Van Staden ◽  
Sandy Tirtey
Keyword(s):  
Control Strategy ◽  
Attitude Control ◽  
Cold Gas

Attitude control strategy for unmanned wheel-legged hybrid vehicles considering the contact of the wheels and ground

2021 ◽  
pp. 095440702110583
Author(s):  
Hui Liu ◽  
Baoshuai Liu ◽  
Ziyong Han ◽  
Yechen Qin ◽  
Xiaolei Ren ◽  
...  
Keyword(s):  
Control Strategy ◽  
Attitude Control ◽  
Lower Layer ◽  
Hybrid Vehicles ◽  
The Body ◽  
Torque Control ◽  
Whole Body ◽  
Programming Algorithm ◽  
Contact Points ◽  
Motion Generator

During patrol and surveillance tasks, attitude control is crucial for improving the terrain adaptability of unmanned wheel-legged hybrid vehicles. This paper proposes an attitude control strategy for unmanned wheel-legged hybrid vehicles, considering the contact of the wheels and ground. The proposed method can naturally achieve torque control efficiently of each joint actuator and wheel-side actuator and avoid the discrepancy between off-road terrain and stability. First, an inverse kinematics model is established to resolve the body and each joint rotation angle, and the dynamic model is built based on the multi rigid body theory, considering the contact points planning of wheel and ground. Considering the nonholonomic constraint of the structure scheme, a hierarchical real-time attitude controller for a wheel-legged vehicle is proposed. The upper layer calculates the contact points of each wheel and the ground through the quadratic programming algorithm, and the lower layer is divided into a legged motion generator and a wheel motion generator by a mathematical analysis method. Finally, the proposed method is applied to achieve the tracking and control of the whole-body trajectory. The proposed strategy can achieve the decoupling of wheeled motion generator and legged motion generator, and improve control efficiency.

Attitude Dynamics and Control of Liquid Filled Spacecraft with Large Amplitude Fuel Slosh

2016 ◽  
Vol 33 (1) ◽  
pp. 125-136 ◽  
Author(s):  
M.-L. Deng ◽  
B.-Z. Yue
Keyword(s):  
Control Strategy ◽  
Attitude Control ◽  
Large Amplitude ◽  
Lyapunov Theory ◽  
Attitude Dynamics ◽  
Equivalent Mechanical Model ◽  
Attitude Maneuver ◽  
Dynamics And Control ◽  
Fuel Slosh ◽  
And Control

AbstractThis paper focuses on the attitude dynamics and control of liquid filled spacecraft, and the large amplitude fuel slosh dynamics is included by using an improved moving pulsating ball model. The moving pulsating ball model is an equivalent mechanical model that is capable of imitating the whole liquid reorientation process, specifically for the occurrence of large amplitude slosh. This model is improved by incorporating a static capillary force and an effective mass factor. The improvements on this model are validated with previously published experiment results. The spacecraft attitude maneuver is implemented by the momentum transfer technique, and the feedback control strategy is designed based on Lyapunov theory. The effects of liquid viscosity, tank location and desired steady time on sloshing torque and control torque are investigated. The attitude control strategy applied in this paper is proved to be applicable for the coupled liquid filled spacecraft system. The obtained conclusions are useful to aid in liquid filled spacecraft overall design.

Sign in / Sign up

Export Citation Format

Share Document