The goal of the project was to produce slotted single-lap shear specimens using continuous ultrasonic welding, which had not been done before. These aim to provide more reliable lap shear strengths than currently used coupons due to increased assembly stiffness and eliminated squeeze-out. By increasing the weld width and stacking smaller rotated adherends, fully welded coupons could be extracted and subsequently slotted. However, high-quality welds were not yet obtained consistently due to pre-heating of the adherends, resulting in overheating during about the second half of these welds. The produced slotted coupons showed the viability of using this configuration, the best achieving 1% under-welding and 90% of the co-consolidated slotted coupon reference lap shear strength, despite not being fully optimized. However, slot precision is essential. In contrast, welded conventional coupons likely yield non-conservative strengths, reaching 109% of the reference, possibly due to the squeeze-out and adherend geometrical distortions resulting from welding. ... Read more

The purpose of this report is to design and iterate all the subsystems of a drone for Mars exploration. Based on a design option analysis and tradeoff, the vehicle is designed to be a VTOL tilt rotor. The mission need statement is: Enable largescale targeted exploration of the atmosphere and surface of currently inaccessible areas of Mars. This mission statement resulted in two expedition types: collect and return expeditions in which soil samples are collected, and remote sensing expeditions where visual mapping, height mapping, gas analyzing and dust composition data is collected and. The project objective statement is: Design a semiautonomous unpiloted atmospheric vehicle that can assist human Martian exploration by observing remote areas and collecting atmosphere and soil samples from difficulttoreach places... ... Read more