Design and transputer realisation of the simulation, control and testing algorithms for a spacecraft docking process

One of the basic problems related to the process of spacecraft docking is the quality of the docking process. There are several approaches to decision making for this task, but the most benefit can be gained through improvement in design quality and the creation of a new control system. The work undertaken and described in this thesis attacks the decision of the problem. In this thesis a mathematical model of the spacecraft at the docking stage is formulated. The influence of the limit of construction rigidity and liquid oscillation to the central body motion is taken into account in this model. This model provides a judgement concerning the results of control in the on-board intelligent control system. This model may be used as a part of the combined test bench for testing of apparatuses and devices of the docking units. The mathematical model of the docking control system includes a model of the orientation system, a model of the stabilisation system, a model of the linear motion control system and semiautomatic and automatic control. This model was realised and is presented as structure schemes. A model of the docking process had been created. This model is a combination of the mathematical model of the two spacecraft and models of their control systems. The estimation of the suitability of the intelligent control system for the task of spacecraft docking is carried out. The use of an intelligent control system makes it possible to increase the reliability of docking operations, and to produce these operations without control from Earth. A mathematical model of the object is necessary for use within the required expert system. Simultaneous calculation of different models with different control strategies makes it possible to determine the most effective control algorithm. This algorithm is selected by the Knowledge Base within the intelligent control expert system taking into consideration information about the condition of the environment and object. A parallel algorithm for optimum control was realised and tested. This algorithm is based on Pontijagin’s maximum principle. This algorithm is used as an element within the Knowledge Base and it provides the minimum time for the transfer of the object from one point to other. The parallel realisation of this algorithm makes it possible to achieve real time control. The developed mathematical models of the object are realised on a multiprocessor network. Simulation is carried out in real time, which allows the use of this model within the intelligent control system. Efficient parallel processing requires the effective multiprocessor network management. The developed algorithm for distributed dynamic dispatching of the transputer network resources provides the full use of the network. It provides the possibility to account the size of tasks as a fuzzy interval and makes the effective decision of noncyclic tasks.

Name dc:type.qualificationname

PhD

Level dc:type.qualificationlevel

Doctoral

Grantor dc:publisher.institution

De Montfort University

Year dc:date.issued

1988

Author dc:creator

• Necklydoff, Alexander

Licence

• https://dora.dmu.ac.uk/bitstreams/5cbe029f-da01-4b52-86bc-8bf21d59a4b8/download