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Show COLLEGE OF ENGINEERING SARRUS-BASED PASSIVE MECHANISM FOR ROBOTIC PERCHING K. Beau Freckleton (Michelle Burroughs, Jake Abbott, Mark Minor) Department of Mechanical Engineering University of Utah 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 due primarily to a lack of energy supply, requiring operators to replace the battery source before the quad-rotor completes its designated purpose [1]. In this paper, w e introduce a mechanism to enable flying robotic rotorcraft, such as quadrotors and helicopters which utilize vertical take-off and landing, to perch similar to a bird. The mechanism is passive, using only the weight of the rotorcraft for actuation. Such a mechanism will dispel the need for multiple batteries by allowing the quadrotor to perch amid its designated flight course, recharge using solar energy, and complete data collection over large scale areas in less time. In previous research to this same end, 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. W e began by designing the mechanism for a range of cylindrical perch sizes. Using MATLAB, w e developed a program to optimize the various mechanism dimensions needed to perch within this range while also maximizing the mechanical advantage of grip force. Using SolidWorks, a 3-dimensional model was created and manufactured with these dimensions. In testing, the mechanism successfully allowed a small RC helicopter to perch on a 4 cm 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. Further research will focus on decreasing these moment forces'ability to weaken the mechanism while optimizing perching capability. [1] P. P. Neumann, S. Asadi, A.J. Lilienthal, M. Bartholmai, and J. H. Schiller, "Autonomous gas-sensitive microdrone: Wind vector estimation and gas distribution mapping," IEEE Robotics and Automation Magazine, vol. 19, no. 1, pp. 50-61,2012. CAD Model of Sarrus based Mechanism Prototype with RC Helicopter in Perching K. Beau Freckleton Jake J. Abbott Mark A. Minor |