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Bumblebees cannot fly! That conclusion is likely to be drawn by scientists who analysed the insect using aerodynamics of stationary wings such as that of a passenger aircraft. Looking at the insect again using a newfound understanding of unsteady aerodynamics; it is clear why bumblebees can fly. Bumblebees utilise mechanisms behind unsteady aerodynamics such as leading-edge vortices (LEVs) formation, wake capture, and rapid end-of-stroke rotation to generate forces that enable the insect to fly. This study focuses on two-dimensional (2D) elliptical airfoil. Earlier works found the aerodynamic characteristics of an elliptical airfoil to differ greatly from a conventional airfoil, and that this airfoil shape could generate the counter-rotating vortices used by insects to generate lift. Therefore, this research aims to study the lift generation of a bumblebee-inspired elliptical airfoil in a normal hovering flight. This study focuses on hovering flight with the insect flies in a nearly stationary position, which explains the importance of lift generation to stay aloft. The motion of the elliptical airfoil is inspired by the flapping kinematics of bumblebees at a typical Reynolds number range of . It is found that the current two-dimensional model is capable of capturing the counter-rotating vortices and correlates the formation of these structures to a high production of lift. These results show that bumblebees utilise these counter-rotating vortices to generate lift enough to fly in hovering flight. This results also indicate that flapping 2D elliptical airfoils can be used to investigate their 3D wing counterparts, which translate to a reduced time and computing costs.

Kontes Mobil Hemat Energi (KMHE) merupakan lomba tingkat nasional yang diselenggarakan oleh Kementerian Riset dan Teknologi Indonesia yang bertujuan untuk mewadahi kreativitas mahasiswa seluruh Indonesia dalam merancang, membangun, menguji dan menyelenggarakan kompetisi mobil hemat energi yang aman dan ramah lingkungan. Peserta dari kegiatan ini adalah seluruh mahasiswa teknik di Indonesia. Penelitian ini membahas mengenai rancang bangun sistem kelistrikan mobil hemat energi yang telah sesuai regulasi KMHE 2019. Metode yang digunakan dalam penelitian ini adalah melalui simulasi Simulink MATLAB dengan menggunakan sistem kontrol Proportional Integral Derivative (PID). Hasil simulasi dengan program Simulink MATLAB R2020b menunjukkan bahwa motor BLDC dengan kecepatan putar 100-900 rpm menghasilkan torsi motor sebesar 30 Nm dan memiliki daya sekitar 960 W. Hal ini menunjukkan bahwa motor BLDC telah melebihi kebutuhan perancangan mobil listrik. Kata Kunci: KMHE, motor BLDC, ramah lingkungan, sistem kelistrikan, torsi motor.