Robot could help turtle conservation - Science News | Daily News from The Irish Times - Wed, Apr 24, 2013
Scientists have developed a robot that mimics the movements of a newborn sea turtle as it struggles across the sand towards water. They hope the “Flipperbot” may aid in turtle conservation by learning more about locomotion on complex and uneven surfaces.
For the full text of the article in the current edition of Bioinspiration and Biomimetics search the Journal Title in the Libraries eJournals search tab on the Library home page.
Abstract: To discover principles of flipper-based terrestrial locomotion we study the mechanics of a hatchling sea turtle-inspired robot, FlipperBot (FBot), during quasi-static movement on granular media. FBot implements a symmetric gait using two servo-motor-driven front limbs with flat-plate flippers and either freely rotating or fixed wrist joints. For a range of gaits, FBot moves with a constant step length. However, for gaits with sufficiently shallow flipper penetration or sufficiently large stroke, per step displacement decreases with each successive step resulting in failure (zero forward displacement) within a few steps. For the fixed wrist, failure occurs when FBot interacts with ground disturbed during previous steps, and measurements reveal that flipper generated forces decrease as per step displacement decreases. The biologically inspired free wrist is less prone to failure, but slip-induced failure can still occur if FBot pitches forward and drives its leading edge into the substrate. In the constant step length regime, kinematic and force-based models accurately predict FBot's motion for free and fixed wrist configurations, respectively. When combined with independent force measurements, models and experiments provide insight into how disturbed ground leads to locomotory failure and help explain differences in hatchling sea turtle performance.