סמינר מחלקה של - דרור קובו - "תכנון, ייצור ובדיקה של מנגנון שליטה על ציפה ורובוט תת ימי בהשראת השטגב"

SCHOOL OF MECHANICAL ENGINEERING SEMINAR
Wednesday, October 6, 2021 at 14:00
Wolfson Building of Mechanical Engineering, Room 206

Design, Fabrication and Control of a Backswimmer

Bio-inspired Buoyancy Mechanism and Robot

Dror Kobo

Msc  Bat El Pinchasik

Autonomous underwater vehicles (AUV) and remotely operated underwater vehicles (RUV) are used to perform a variety of tasks in marine environments. Miniature underwater robotics is an emerging research field that presents great potential for creating economic and efficient robotic swimmers, compared to existing, relatively large, robots for exploring the aquatic environment.

In nature, one can find aquatic insects that rely on an external air bubble, namely plastron, taken from the surface of the water to provide them with oxygen for respiration. The backswimmer (Notonectidae, Anispos) is an aquatic insect with diving capabilities, which developed a unique mechanism to regulate the volume of a trapped air bubble using hemoglobin found in trachea cells in its abdomen. In this way, it can achieve neutral buoyancy. The use and manipulation of gas bubbles is a new method to solve a complex problem: buoyancy regulation in underwater robots.

In this study, a backswimmer inspired millimeter-scale robotic device is developed, with depth control and an ability to maintain precise spatial location. During operation, the robotic vehicle switches between different swimming modes that include sinking, ascending and neutral floatation to reach and maintain a certain working depth, determined by the operator. A small buoyancy mechanism, that does not rely on motorized pistons and pressurized air tanks, may contribute to the overall miniaturization of robots underwater.