• Journal of Satellite, Information and Communications
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• v.12 no.3
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• pp.108-113
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• 2017

The OBCP called 'operator on board' is that of a procedure to be executed on-board, which can be easily be loaded, executed, and also replaced, without modifying the remainder of the FSW. The use of OBCP enhances the on-board autonomy capabilities and increases the robustness to ground stations outages. The OBCP engine which is the core module of OBCP component in the FSW interprets and executes of the procedures based on script language written using a high-level language, possibly compiled, and it is relying on a virtual machine of the OBCP engine. FSW team in KARI has studied OBCP since 2010 as FSW team's internal projects, and made some OBCP engines such as Java KVM, RTCS/C and KKOMA on ERC32 processor target only for study. Recently we have been studying ESA's OBCP standard and implementing Lua and MicroPython on LEON2-FT/AT697F processor target as the OBCP engine. This paper presents the design and implementation of Lua for the OBCP engine on AT697F processor with VxWorks RTOS, and describes the evaluation result and performance of the OBCP engine.

• Journal of Satellite, Information and Communications
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• v.9 no.4
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• pp.127-133
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• 2014

In this paper, we present the design, functions and performance analysis of the virtual machine (VM) based on the Lua interpreter for On-Board Control Procedure Execution Environment (OEE). The development of the OEE has been required in order to operate the lunar explorer mission autonomously which is planned by Korea Aerospace Research Institute (KARI) autonomously. The concept of On-Board Control Procedure (OBCP) is already being applied to the deep space missions with a long propagation delay and a limited data transmission capacity since it ensure he autonomy of the mission without the ground intervention. The interpreter is the execution engine in the VM and it interpreters high-level programming codes line by line and executes the VM instructions. So the execution speed is very more slower than that of natively compiled codes. In order to overcome it, we design and implement OEE using register-based Lua interpreter for execution engine in OEE. We present experimental results on a range of additional hardware configurations such as usages of cache and floating point unit. We expect those to utilized to the OBCP scheduling policy and the system with Lua interpreter.