Pointing Error Engineering Software Framework
Programme: | GSTP | Achieved TRL: | 4 |
Reference: | G617-036EC | Closure: | 2016 |
Contractor(s): | Astos Solutions (DE), Airbus DS (DE) |
The ECSS Control Performance Standard E-ST-60-10C and the ESA Pointing Error Engineering Handbook ESSB-HB-E-003 introduced a mathematically well-founded step-by-step process with guidelines, recommendations and examples to perform pointing error engineering tasks (as opposed to traditional simplified summation rules previously used). To promote dissemination and enhance application of these documents, a prototype Pointing Error Engineering Tool (PEET) was developed in 2012 to carry out preliminary pointing error engineering tasks (up to Phase A). The PEET prototype was designed as an extension to Mathworks MATLABĀ® and was restricted to the simplified statistical method (i.e. assuming applicability of the central limit theorem in level of confidence evaluation).
Objectives
Following the successful development of the prototype PEET, the development of an enhanced, extended, and verified SW framework was initiated with the objective to support several types of missions in all project phases. The SW framework development was driven by the need to increase the user-friendliness, improve the reporting functionality, and upgrade the mathematical foundations of the tool to address the needs of high-accuracy pointing missions (i.e. not restricted to the simplified statistical method). In addition, another key objective was the execution of a thorough verification and validation campaign to strengthen acceptance and confidence from industry.
Achievements
With the completion of this GSTP activity, a verified and more user-friendly version of PEET (PEET 1.0), enhanced with advanced statistical methods (whereby the central value theorem is assumed not applicable), is available for the European space community. PEET 1.0 can process complex calculations for high accuracy pointing missions and can provide traceability and a common platform for exchange of information between various entities (space agencies, industrial prime contractors, industrial sub-contractors, satellite operators, etc.).
PEET 1.0 will be released to the European space community on the webpage www.peet.estec.esa.int in the near future.
Benefits
PEET 1.0 computes statistical/spectral error budgets applicable throughout all project phases (by means of an adjustable level of accuracy and detail) using standardised methods and techniques.
PEET 1.0 is well-suited for integration in analysis tool chains (e.g. sensitivity analyses, automatised break-down of requirements) thanks to the available Excel & Matlab interfaces.
Limitation: PEET 1.0 cannot explicitly account for non-linearities and transient system behavior, i.e. it is not intended as a replacement for end-to-end simulators. However, it can steer the design into the right direction thanks to the capability to responsively provide simplified assessments.
Further activities
Further efforts will be required to update the ESA Pointing Error Engineering Handbook based on lessons learned during the implementation of PEET 1.0 and to support the maintenance and possible extension of PEET with modules for specialised applications.