Jump-flying: a Bioinspired Hybrid Locomotion Strategy for Small Mobile Robots

点击翻译按钮获取中文摘要

Small Unmanned Air Vehicles (UAVs) are becoming increasingly useful in performing short missions for mapping, mining, agriculture, construction, environmental management and disaster response. However, current technology limits flight endurance, and several mission scenarios require longer operations. Frequent landings, on ground or water bodies, have the potential to effectively extend the mission duration by allowing for recharge. Although repeated landings and takeoffs provide several additional benefits, most small UAVs are designed without this functionnality since the added design constraints significantly compromise cruise performance (e.g., flight time, range, speed). Observation of nature provides key insight to engineer new solutions to reduce these long-standing takeoff limitations. Indeed, at small scales, jumping is the preferred takeoff method in nature, and birds and insects of all sizes and flight abilities use jumping to transition to flight, either from land or from water. This research program investigates jumping as a transition to flight, which we term "jumpflying". This hybrid locomotion mode has the potential to allow small UAVs to repeatedly land and takeoff without imposing significant constraints on the propulsion system. Exploratory work by the author led to the development of a "jumpgliding" UAV, which exploits a passively pivotable wing. This UAV is the first to demonstrate efficient takeoffs and airborne trajectories substantially longer than an equivalent ballistic jumper. The research outlined in this proposal aims to leverage this recent breakthrough in jumpgliding to develop powered jumpflying. It is foreseen that this research will lead to three innovative jumpflying strategies: frequent high jumps followed by short glides, few small jumps followed by a long flight phase, and powerful multidirectional jumps followed by highly agile flights. To evaluate the conditions under which, and to what extent, each of these is appropriate, this research will investigate questions pertaining to : (1) startup dynamics of the propeller at low flight speeds, (2) short flights with significant takeoff constraints, transient aerodynamics and ground effects, (3) the possibility of sharing flight and jumping actuators to reduce added mass and (4) jumping from a water surface. When combined with classical airplane multidisciplinary optimization techniques, the detailed knowledge gained through this research will lead to a comprehensive understanding of jumpflying and prototypes optimized for various missions. Finally, cruise performance and takeoff abilities of theses prototypes will be compared against existing UAVs and model airplanes. It is expected that in the long term jumpflying will lead to a practical and extremely energy-efficient locomotion mode capable of alternating between ground and air operations. With recharge capabilities, jumpflying effectively increases the mission duration of small UAVs from minutes to days, while maintaining flight performance. The jumpfliers developed will enable a range of new applications that require long mission durations. For example, a team of jumpfliers could be deployed on many of the Northern Canadian lakes, alternating between surveying for forest fires and charging onboard solar batteries. Other applications include relocatable sensor arrays, sample and return missions, tracking of toxic spills, and surveillance. This five-year project will train six graduate students in the areas of robotics, aeronautics, bio-inspired design, dynamics, control, and fabrication.