Lunar Zebro’s mission is heading the race for deploying the world’s smallest and lightest swarm of nanorovers on the surface of Moon. The concept validation of a single nanorover is of crucial importance, as it will be the launching pad for deploying a swarm of those nanorovers thereafter. Then, they will get connected in a network, acting as a single device and performing scientific missions analyzing data from remote points on the Moon’s surface. In the current study, the complete set of thermo-mechanical-radiation analyses for Lunar Zebro nanorovers are carried out. These range from the Ground Segment to the Moon environment, taking also into account the extreme mechanical and thermal environment at launch-transit conditions when the nanorover is attached to the lander. An innovative ray tracing method to evaluate the effect of the thermal environment on the Lunar Zebro nanorovers is explained in this paper. Material choices, structural design, and mechanical/thermal strategies for the nanorover to overcome the launch, space and Moon’s conditions are shown. The different analyses methods used, expected loads and results obtained should serve as a baseline for evaluating the behaviour of other small devices attached to a lander when aiming for any space mission. More specifically, for those aiming to go to the Moon, the environmental and mechanical expectations here can also be implemented. The ultimate outcome of the paper is the environmental survivability assurance from an analytical perspective of these nanorovers when being sent to the Moon. The validation of the survivability of a single nanorover will be a breakthrough in the space swarm robotics’ field, resulting in the successful performance of the lightest swarm of nanorovers ever deployed on the Moon’s surface.

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Deep space missions are exposed to a broad range of temperatures and extremely high doses of radiation when compared to Earth bound space missions. Although standard passive and active strategies have been developed to protect spacecraft subsystems from fatal levels of radiation and unacceptable temperature levels inside the spacecraft, environmental analysis is a non-linear discipline which changes from project to project and therefore needs to be analyzed independently. Specially, taking into account the singular features which characterize each space mission. On the other hand. given that every kilogram launched beyond Earths orbit has signicant associated costs, space systems miniaturization has become a necessity with increasing popularity, which has driven the recent trend in the enhancement of this technology. These small complex systems need to be precisely simulated and verified with realistic simulations and experimental tests so that in an unexpected environmental situation, the risk of a total mission failure is reduced to the minimum. To accomplish mission requirements in terms of cost, mass and energy utilization for miniature spacecraft, passive thermal control systems (PTCS) are sought. In this project, Lunar Zebro, miniature space exploration surface vehicles will be connected together in a network, analyzing data from multiple nodes using interferometry; acting all together as a single dish. After introducing and analyzing the technological goals and objectives of this mission, the focus shifts into the environmental analysis of a single rover from this swarm. Its thermal behaviour is addressed in all mission phases, beginning from its performance on ground through to the Moon's surface, taking into account different possible scenarios. To do so, an own program is created (in MATLAB), in which an easy-to-apply and computationally efficient Ray Method is implemented. Among other applications, Visual Factors between the various faces of the rover and different heat sources (e.g. the Sun or Moon albedo) are computed using that methodology, which is explained in a step-by-step guide to be applied in any other software for other missions. To validate the model's accuracy and enhance the rover's thermal scope of knowledge, results will be compared to those obtained from ANSYS, a dedicated program for thermal applications. Recommendations for implementing the thermal analysis, together with limitations and future improvements of the method are also addressed. On the other hand, to get the complete overview of the environmental analysis of the mission, radiation issues are analyzed as well, taking into account the worst possible scenario. Outputs coming from this analysis will determine what is the optimal solution for protecting the rover. Finally, conclusions and future work to do in this mission are covered.@en