## 5 Testing and Navigation
### Testing Strategy  
Robustness is a key point for the Microtransat Challenge. Each part of the boat must be carefully designed, built, and tested. To enhance reliability, the system must be kept as simple as possible, and the number of parts reduced as much as possible to reduce the failure probability. For every part and every part modification, there are several levels of tests to pass. The validation process consists of nine test types to be run in succession. The first step consists of unit tests run using the simulation of an electronic component, and must be accomplished for any increment in the controller software or any change in component. The objective is to verify that the component reacts as expected to any given entry. The second step consists of verifying a model of the integrated system. The components are integrated in all or part of the system and tested in realistic conditions to verify functional specifications. Simulations are also used to predict the expected behaviour of the mechanical design. For example, the load can be estimated for a new rudder design, as explained in [18]. Hardware in the Loop (HIL) can be advantageously implemented during this step to evaluate all supply chain [23]. This leads to the third and fourth validation steps, which are, respectively, the unit test and the integration test in laboratory. Then, the fifth step is conducted outdoors, ideally in a large open space free from any interference. A soccer playground was utilized for this during the design of SeaLeon, and the boat was installed on a trolley. Navigation was emulated by controlling the different sensor inputs manually, and the system reaction, such as the sails or the rudder angles, were observed and verified. During the sixth step, navigation on water is assessed in light winds at less than ten knots, and a predefined path is programmed with waypoints. The chosen location must be inshore and allow easy recovery. For the design of the Breizh Tigresse and SeaLeon, the Northwest Arm in Halifax was particularly suitable for these tests, and the boat's ability to maneuver in any directions at any point of sail was assessed using three waypoints configured at three vertices of a triangle with approximately 150 m separation between the waypoints. During this step, the maneuvering qualities and ability to tack and jibe without difficulties are also tested. The next two test series consist of strong wind tests. Here, the robustness of the design is confronted with a real situation. First, these tests can be conducted inshorse, in a lake or harbor, then in high sea to additionally assess the resistance to hydrodynamic loads with high waves. Finally, the ninth step is the endurance test, which is the most costly, because it requires the mobilization of several team members \begin{table}
\begin{tabular}{l c c} \hline
**Property** & **LiSOC1\({}_{2}\) PT-2300** & **LiFePO\({}_{4}\) LF280** \\ \hline Voltage (V) & 14.8 & 12.8 \\ Capacity (Ah) & 19 & 280 \\ Unit Cost (USD) & 14 & 116 \\ Weight (g) & 388 & 20,880 \\ Volume (cm\({}^{3}\)) & 267 & 10,168 \\ Cost/Cap. (USD/Ah) & 2.9 & 1.7 \\ Weight/Cap. (g/Ah) & 20 & 75 \\ Volume/Cap. (cm\({}^{3}\)/Ah) & 14 & 36 \\ \hline \end{tabular}
\end{table} 
Table 5: Comparison of LiSOC1\({}_{2}\) versus LiFePO\({}_{4}\) battery. and material for several days. In fact, a chase boat able to operate in rough sea is needed to follow and recover the drone. In this last stage, the resilience of each part is tested. It is very important to note that, at this point, it is possible that the entire vessel is lost; therefore, it must only be conducted after successfully passing the eight former steps. For the Breizh Tigress, the hull was provided by Ensta-Bretagne. Several components of the sailboat needed to be rebuilt, including the rigging and sail, as well as the power supply and controller. After having completed the design and tested all the individual components, several tests were run on the water, including short-term navigation tests in Halifax's Northwest Arm.