Abstract In this paper, we first presented a four-bar linkage mechanism for actuating the wings in a flapping wing flying robot. After that, given the additional constraints imposed by the four-bar linkage, we parameterized the wing kinematics to provide sufficient control authority for stabilizing the system during 3D hovering. The four-bar linkage allows the motors to spin continuously in one direction while generating flapping motion on the wings. However, this mechanism constrains the flapping angle range which is a common control parameter in controlling such systems. To address this problem, we divided each wingbeat cycle into four variable-time segments which is an extension to previous work on split-cycle modulation using wing bias but allows the use of a constant flapping amplitude constraint for the wing kinematic. Finally, we developed an optimization framework to control the system for fast recovery while guaranteeing the stability. The results showed that the proposed control parameters are capable of creating symmetric and asymmetric motions between the two wings and, therefore can stabilize the hovering system with minimal actuation and flapping angle amplitude constraint. 
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                            Design and Manufacturing of Flapping Wing Mechanisms for Micro Air Vehicles
                        
                    
    
            Stringent size, weight, and power constraints imposed on flapping-wing micro-air-vehicles (FWMAVs) make their design quite challenging. In particular, the flapping actuating mechanism represents a corner stone in the design of the whole vehicle, if not the most challenging task. In this paper, we provide a review on the several designs of flapping mechanisms in literature and compare their performances. We also provide our design and manufacturing iterations that culminated in a novel design of a FWMAV actuating mechanism that actively controls both the wing flapping (back and forth) and pitching motions using only one drive motor. In this design, we use a parallel crank rocker mechanism. Synthesis and optimization of the parallel crank rockers allowed independent control of the wing flapping and pitching angles. That is, the two angles are allowed to simultaneously follow speci c independent functions using only one drive motor. The designed mechanism is manufactured (3D printed), tested, and found to successfully achieve the desired wing motions that mimic the motion of a hummingbird wing. 
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                            - Award ID(s):
- 1636017
- PAR ID:
- 10025383
- Date Published:
- Journal Name:
- 58th AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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