A. R. Alemi Naeeni; J. Roshanian
Volume 6, Issue 4 , January 2014, , Pages 53-62
Abstract
In this paper, a multi-objective guidance scenario has been developed which could be used to improve the accuracy of sub-orbital modules at the entry to the earth’s atmosphere. Developed algorithm could be used for the trajectory shaping and adjusting of the trajectory relative to the desired position. ...
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In this paper, a multi-objective guidance scenario has been developed which could be used to improve the accuracy of sub-orbital modules at the entry to the earth’s atmosphere. Developed algorithm could be used for the trajectory shaping and adjusting of the trajectory relative to the desired position. To achieve defined objectives, it has been organized in three phases relative to different layers of trajectory. In the first phase, using of sensitivity functions which are of less computational burden, improving the accuracy according to the reference trajectory is done. In the second phase, trajectory shaping which is required to achieve desired flight performance is applied which could be designed and performed online in the mission. Finally in the last phase which is relative to low altitudes, improving of the accuracy according to homing rules is performed. Validation of developed algorithm using of a sample guidance problem is presented finally.
A. R. Alemi Naeeni; J. Roshanian
Volume 6, Issue 3 , October 2013, , Pages 15-26
Abstract
This paper presents an explicit guidance method which could be used in the problems of orbit correction for sub-orbital modules. This method is based on solving the Lambert problem. Two efficient methods of solving the Lambert problem are introduced and compared. Using of the selected method a guidance ...
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This paper presents an explicit guidance method which could be used in the problems of orbit correction for sub-orbital modules. This method is based on solving the Lambert problem. Two efficient methods of solving the Lambert problem are introduced and compared. Using of the selected method a guidance scenario is developed which is capable of solving the problem under investigation. All of the methods of solving the Lambert problem, are based on spherical gravitational field and aerodynamic forces are not considered by them. In order to consider those important factors, a method is presented which increases the accuracy of guidance block computations. Finally using of developed method, two sample problems are investigated. Applying the developed method, a guidance block is prepared which performs the required maneuvers in a mission. Monte Carlo simulation confirms the ability of developed method in different conditions.
