A Perching Landing Gear for a Quadcopter

Abstract

The design, fabrication, and testing of two prototypes of a landing gear mechanism that would allow a quadcopter to grasp and perch upon a branch-like structure are presented. The prototypes are based upon a snapping-claw mechanism that is triggered on the impact of landing. A complaint claw, fabricated using shape deposition manufacturing techniques, can conform to various shapes and contours of perching structures. Results from flight tests with a commercial off-the-shelf quadcopter and zip line tests are presented which demonstrate the performance of the mechanism. NomenclatureE = Young's modulus σ x = yield stress ρ = density τ = torque

Bird-inspired dynamic grasping and perching in arboreal environments

“…Other grasping mechanisms can pick up different stationary objects (20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30) or catch objects launched at them (28,31,32). Some demonstrated vertical or near-vertical landings on irregular or cylindrical surfaces (21,29,31,(33)(34)(35)(36)(37)(38)(39)(40), including posed branches and a single tree branch (34). Whereas some birds are capable of landing vertically in a slow hovering flight fashion, most of the time, they make a dynamically controlled collision.…”

Touchdown to take-off: at the interface of flight and surface locomotion

“…These surfaces can be gripped from any direction, and allow for slight misalignment on contact. Many enclosed grasping mechanisms use jointed or compliant fingers [55,56,[169][170][171][172][173][174][175], though others involve simply hooking and hanging (figure 3a,n) [58]. By contrast, one unusual modular snake-like robot wraps its entire body around cylinders upon contact (figure 3i) [59].…”

A Sarrus-Based Passive Mechanism for Rotorcraft Perching

“…Daler et al [27] developed a mechanism comprising fiber-based adhesive that enables perching on flat, vertical surfaces. In works that have a similar motivation to ours, Culler et al [28] developed a gripping mechanism for a quadrotor, which uses a compliant snapping claw mechanism that is triggered upon landing on a branchlike structure. Although the mechanism proposed here is also intended for cylindrical branchlike structures, it can actually grip a range of perch shapes and it is quite different from related work since it relies solely upon gravitational forces to close the gripper and exert sufficient forces to grasp the perch.…”