| Description |
Current quad-rotors provide excellent maneuverability and opportunity for data collection in large scale areas such as agriculture, but lack the capability to maintain flight for an extended period of time. This is primarily due to a lack of energy supply, requiring operators to replace the battery source before the quad-rotor completes its designated purpose. We introduce a mechanism to enable flying robotic rotorcraft, which utilizes vertical take-off and landing, to perch on branches or rods, similar to a bird. The mechanism is passive, using the weight of the rotorcraft for actuation. Such a mechanism will dispel the need for multiple batteries by allowing a rotorcraft to perch amid flight course, recharge using solar energy, and complete data collection in less time. In previous research work, biomimetic approaches were pursued, resulting in designs that looked similar to the legs and feet of birds. The design in this paper utilizes a Sarrus mechanism to convert rotorcraft weight into perch grip. Using MATLAB, we developed a program to optimize the various mechanism dimensions needed to perch within a range of diameters while also maximizing the mechanical advantage of grip force. Using SolidWorks, a 3D model was created and manufactured. In testing, the mechanism successfully allowed a small RC helicopter to perch on a 40 mm diameter rod with some resistance to external forces. However, in crash tests, the mechanism was unable to withstand certain moment forces and developed large fractures. Using the same software, several more design iterations were developed in conjunction with FEA, structural integrity characteristics, and helicopter payload considerations. The outcome of these iterations is a second prototype which proved structurally more reliable than the first prototype and outputs a grip force predictable with the MATLAB simulation. This thesis elaborates on work coauthored with Burroughs[5] where Burroughs focused on the dimensional optimization of the mechanism grip force using MATLAB in her thesis[6], whereas this thesis primarily focuses on the prototyping using SolidWorks and the mass optimization of the mechanism. |
