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- All Subjects: Granular Media
- Creators: Bagheri, Hosain
Description
Traditional wheeled robots struggle to traverse granular media such as sand or mud which has inspired the use of continuous tracks, legged, and various bio-inspired designs in recent robotics research. Animals can navigate the natural world with relative ease and one animal, the Basilisk lizard, can perform the amazing feat of bipedal water and land running. Through the observation and study of basilisk lizards of the common and plumed variety, inspiration and development of a robotic platform was completed. After fabricating the bio-inspired robot, parameters unchanged by the animals were varied to characterize the combined effects of stride length and frequency on average velocity. It was found that animals increased stride length at higher saturation levels of sand to increase their velocity rather than increase their step frequency. The BasiliskBot version one was unable to change its stride length as the wheel-legs or "whegs" of this version were set at four spokes. Bipedal running of the robot was slower than quadrupedal running due to sand reaction forces and tail drag. BasiliskBot version two was lighter than the first version and had a range of stride lengths tested with increasing spoke numbers from 3-7. At lower step frequencies and lower wheg numbers, higher average velocity could be achieved compared to higher wheg numbers despite the highest maximum velocity being achieved by the highest number of spokes. A comparison of transition strategies for common and plumed basilisks showed both species chose to jump and swim through water more often than jump and run across water which achieved the highest average velocity. Results of transition strategies study pertain to future developments of the robot for amphibious purposes. Weight experiments were performed to assess the ability of the robot to carry sensors and other payloads. Added weight increased the highest frequency allowable before failure, but also caused failure at low step frequencies that had not displayed failure previously.
ContributorsBurch, Hailey (Author) / Marvi, Hamidreza (Thesis director) / Bagheri, Hosain (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
August Krogh, a 20th century Nobel Prize winner in Physiology and Medicine, once stated, "for such a large number of problems there will be some animal of choice, or a few such animals, on which it can be most conveniently studied." What developed to be known as the Krogh Principle, has become the cornerstone of bioinspired robotics. This is the realization that solutions to various multifaceted engineering problems lie in nature. With the integration of biology, physics and engineering, the classical approach in solving engineering problems has transformed. Through such an integration, the presented research will address the following engineering solution: maneuverability on and through complex granular and aquatic environments. The basilisk lizard and the octopus are the key sources of inspiration for the anticipated solution. The basilisk lizard is a highly agile reptile with the ability to easily traverse on vast, alternating, unstructured, and complex terrains (i.e. sand, mud, water). This makes them a great medium for pursuing potential solutions for robotic locomotion on such terrains. The octopus, with a nearly soft, yet muscular hydrostat body and arms, is proficient in locomotion and its complex motor functions are vast. Their versatility, "infinite" degrees of freedom, and dexterity have made them an ideal candidate for inspiration in the fields such as soft robotics. Through conducting animal experiments on the basilisk lizard and octopus, insight can be obtained on the question: how does the animal interact with complex granular and aquatic environments so effectively? Following it through by conducting systematic robotic experiments, the capabilities and limitations of the animal can be understood. Integrating the hierarchical concepts observed and learnt through animal and robotic experiments, it can be used towards designing, modeling, and developing robotic systems that will assist humanity and society on a diversified set of applications: home service, health care, public safety, transportation, logistics, structural examinations, aquatic and extraterrestrial exploration, search-and-rescue, environmental monitoring, forestry, and agriculture, just to name a few. By learning and being inspired by nature, there exist the potential to go beyond nature for the greater good of society and humanity.
ContributorsBagheri, Hosain (Author) / Marvi, Hamidreza (Thesis advisor) / Berman, Spring M (Committee member) / DeNardo, Dale F (Committee member) / Emady, Heather N (Committee member) / Lee, Hyunglae (Committee member) / Arizona State University (Publisher)
Created2020