The objective of this study is to demonstrate the complete capabilities of the AEPD system to be used as a standard tool for EP thrusters on-ground characterisation.

The proposed project is based on the Advanced Electric Propulsion Diagnostic (AEPD) system recently developed within ESA/ESTEC contract N# 20461/06/NL/CP.The AEPD system consists of a high precision five-axis positioning system and currently 5 diagnostic tools (telemicroscope, triangular laser head, pyrometer, Faraday probe, energy-selective mass spectrometer). The capabilities of the AEPD system were demonstrated in two vacuum facilities of different sizes and with two different types of thrusters (GIE - RIT 22 - and HET - PPS1350 or SPT100 -. However the tests revealed critical issues of the test setup:- telemicroscope, triangular laser head and pyrometer are placed in a vacuum sealed housing at atmospheric pressure inside. The housings make the diagnostic head quite large and the use of normal pressure inside the housing bears some vacuum failure risks in case of damage to the housing's viewports or the housing itself.- the portfolio of diagnostic tools should be enlarged.- further tests are needed in order to define a standard tool for EP thruster characterisation.In consequence of the critical issues the diagnostic system shall be improved and qualified as a standard tool for EP thruster characterisation. In this activity, the following tasks are proposed":- in order to minimise the interaction between the diagnostic tools and thruster, as well as to minimise the risk of vacuum failure, telemicroscope and pyrometer shall be tested for in-vacuum operation;- additional tools such as thermocamera, differential thrust balance, retarding potential analyser, calorimetric probe shall be included;The APED shall be tested in different test facilities with two different thrusters in order to address chamber effects and diagnostic suitability's for different thruster types.