The attitude determination and control systems (ADCS) task scheduler

[摘要] ENGLISH ABSTRACT:A new task scheduler for the Attitude Determination and Control System (ADCS) ofthe Stellenbosch University Satellite (SUNSAT) has been designed and tested on apersonal computer. This new scheduler is capable of uploading new control tasks, orchanging existing control tasks, on an individual basis. This is an improvement on thecurrent ADCS task scheduler, where the control tasks are hard-coded in thescheduler, requiring the entire software image of the scheduler to be uploaded if anew task is to be added, or an existing task is to be changed.The new scheduler was developed using the Java programming language. The JavaClassLoader class is used to dynamically load tasks to a linked list. The schedulerthread runs through this linked list and schedules all the tasks that have becomeschedulable. New tasks can be added to the list without stopping the scheduler.The new scheduler has been successfully implemented on a personal computer,laying a good foundation for implementation in an embedded environment based onprocessors such as the T800 Transputer of the ADCS or the 80386 processor of thesecondary onboard computer (OBC2).

[发布机构] Stellenbosch University