Trajectory correction maneuver design based on B-plane targeting for low-thruster
For the interplanetary mission, the spacecraft must require the trajectory correction maneuver (TCM) to reduce the trajectory error due to the influence of unexpected external perturbation forces. There are many kinds of researches focused on these TCM techniques for the impulsive thrust. Among them, the B-plane targeting method is mainly applied to the interplanetary mission as TCM method. However, there are brilliant developments in the propulsion systems; especially the electrical propulsion system is adopted in some spacecraft. Thus, it is necessary to design the TCM algorithm for such low-thruster for future interplanetary missions. Therefore, in this paper, the TCM algorithm for the low thrust such like electrical propulsion system is suggested to correct the target B-vector and target time to closest approach (TCA). To design the low thrust guidance scheme, the Lyapunov feedback control is used in this paper.
DERIVATION OF THE B-PLANE (BODY PLANE) AND ITS ASSOCIATED PARAMETERS
When sending a spacecraft to some extraterrestrial body, one navigation and mission design metric used is B-plane (Body Plane) targeting. The spacecraft’s target body miss distance (with its associated covariance) and the target body’s impact radius, can be readily mapped onto this B-plane. Things such as the performance of trajectory correction maneuvers (TCMs) and the effects of dynamic model errors (as well as perturbative effects of angular momentum desaturations {AMDs}) upon the trajectory, can be characterized and optimized in terms of B-plane parameters. It is herein that the advantage of it use is sought and found.
Effect of Force on Finite Element in Vivo Skin Model
This paper presents a computer model, which simulates the skin deformation on a biomechanics/ finite element method (FEM) based design employed in ANSYS, which can be used for medical applications especially for LUPUS (discoid lupus erythematosus) treatment & plastic surgery. This manuscript presents literature reviews and compares the finite element modeling with previously conducted lab & numerical results. The biomechanical model considers the skin as a membrane undergoing large deformations and puts the local coordinate system of each element to its principal strain directions, so that the potency of the skin at that spot can be eminent. The model based on the mechanics with different bio-properties to replicate the skin surface. A Matlabreg based ranges of maximum and average force values were noted for human subjects along with the influence of angle, rate, age & subject. With experiments and the appliance of mechanics, study was conducted to analyze adhesion to skin in ANSYS and then results are compared with pervious results. Two types of models are being used in manuscript: first models dealt with plucking rigid skin surface at different angles and other models concerned plucking slack skin from body at different angles. Results from the experiments and computer-based models are in weigh against. This study will increase knowledge of skin behavior and could contribute to improvements in the design of adhesives that contact the skin