The mechanical design of EPT was driven by the scientific requirements and the demand to keep the size of the instrument to an absolute minimum.
The challenge was to design an instrument capable of science-class measurements on the one hand and having an overall dimension and mass not much higher then the more simple radiation monitors currently flying on board many spacecraft on the other hand.
To do this, the telescope has its sensors and absorbers packed as tightly as possible next to each other. This resulted in a design where heavy absorbers had to be placed in the centre of a fragile sensor at a distance of only 0,9mm.
To be sure to survive the launch, several design iterations and extensive vibration tests had to be performed to reach this goal.
In order to keep the entire instrument as compact as possible, the electronics end wiring was then “wrapped” around the actual telescope with an outer shell to protect the instrument.