The list of E.T.PACK’s Work Packages and the partner leading the activity are:
- Coordination (UC3M)
- LWT Modelling and Simulation (UC3M)
- LWT Manufacturing and Testing (IKTS)
- Deployment Mechanism (UNIPD)
- C12A7:e- Devices (TUD):
- Deorbit Kit (SENER)
Work Package 5 includes the design, manufacturing and testing of a Hollow Cathode Emitter (HCE), a Hollow Cathode Thruster (HCT), and a Photon-Enhanced Thermionic Emission Device (PETED). The deorbit kit based on LWT technology, complemented with these three devices based on the C12A7:e-, will put in contact the following disciplines: space tethers, thermionic materials, plasma physics, microelectronics, orbital dynamics, fine mechanics, electric propulsion, and space systems.
As shown in Fig. 1, the Work Packages (WP) are heavily interconnected in the project that has high cross-fertilization potential. Theoretical results from Work Package 2 (WP2) and preliminary designs of the DK in WP6 will act as inputs to WPs 3, 4 and 5 by setting a set of requirements to the LWT, the deployment mechanism, and the HCE and the PETED, respectively. They will include the target work function, photoelectric yield, absorptivity, emissivity of the LWT, the required tether mechanical characteristic for the deployment mechanism, the nominal current, potential and power for the HCE, and the interfaces for the PETED, among others. In parallel, WPs 3, 4, 5 will feed WPs 2 and 6 with the actual performance of the hardware elements tested in the laboratory. This will allow to simulate accurately in WP2 the LWT performance and also to refine the design of the DK in WP6. Such iterative and collaborative work will identify bottlenecks, and will provide a feedback on critical challenges to be overtaken by the team.
These activities are highly interconnected, risk-friendly, and need cutting-edge research. For that reason, the workplan separated essential and moderate-risk activities, to be carried out during the first two years of the project, from a second iteration that includes more refined activities with higher risk. The project also includes several milestones and decision points that helps to monitor the progress. In particular, there are several backup plans that will be activated in case the expected performance of the hardware and software elements are not achieved. The flexibility of the project is guarantee by two plans of contingency and three alternatives for the DK: based on LWT technology (no consumable and fully passive), bare tether with electron field emitter (no consumable), and bare tether with hollow cathode emitter.