Presented in this paper is a method for analysis and control of an actuation-redundant parallel mechanism requiring synchronization. The said mechanism is made up of two branches that are connected to drive a common end-effector with only one degree-of-freedom of motion. The two actuators must share the load exerted on the common end-effector during motion. The underlying problem is to synchronize the motion of the two actuators while balancing the forces on them so that the entire mechanism can move smoothly under the applied load on the end-effector. Due to the space limitation, the two branches are geometrically different leading to opposite force profiles for the two actuators. The proposed method combines the mechanism kinematics with force analysis. First, a closed-form solution is derived that relates the actuator strokes to the rotation angle of the end-effector. Second, a velocity relationship is obtained to relate the actuator velocities to the angular velocity of the end-effector. Third, a force relationship is established relating the actuator loads to the external load. Fourth, a control strategy is designed to synchronize the motion of the two actuators while maintaining the force balance between them to avoid the problem of motion mismatching and force fighting that could lead to the failure of the mechanism. A prototype was built and tested with the proposed method, which is also presented in this paper.

A loading mechanism for a variable cant angle morphing winglet is proposed in this paper. The mechanism provides a method of loading a morphing winglet with the simulated aerodynamic lift force by maintaining its application direction always orthogonal to the surface of the winglet throughout the range of motion. The loading mechanism is developed by type synthesis of four-bar linkages through enumeration of prismatic and revolute joints. The final design is a R-P-R-P four-bar linkage modified by merging the middle P-R joint together to form a planar joint named Shark-fin. The Shark-fin shape is optimized to minimize its weight effect on the overall loading system. A half-scale prototype was built as a reference to address several implementation issues including the neutral loading condition. Afterwards, a full-size dynamic loading mechanism was successfully constructed and implemented to load test a full-size morphing winglet

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The following thesis paper investigates the possible methods to perform a dynamic load test on a morphing winglet. A morphing winglet design capable of deflecting in the cant direction was developed by a joint partnership between Ryerson University and Bombardier Aerospace. In order to validate the model and complete a proof of concept, a loading fixture was required to test the structural integrity of the winglet under a defined load. Upon completion of an enumeration study of planar four-bar linkages, a passive R-P-R-P mechanism was designed to apply a constant perpendicular load throughout the cant motion. A design of the half size loading fixture was developed, optimized and manufactured to integrate with an existing cant module. The dynamic loading model was validated by producing a positive correlation between the theoretical analysis and the experimental results, leading to a successful proof of concept for a full scale test.

The following thesis paper investigates the possible methods to perform a dynamic load test on a morphing winglet. A morphing winglet design capable of deflecting in the cant direction was developed by a joint partnership between Ryerson University and Bombardier Aerospace. In order to validate the model and complete a proof of concept, a loading fixture was required to test the structural integrity of the winglet under a defined load. Upon completion of an enumeration study of planar four-bar linkages, a passive R-P-R-P mechanism was designed to apply a constant perpendicular load throughout the cant motion. A design of the half size loading fixture was developed, optimized and manufactured to integrate with an existing cant module. The dynamic loading model was validated by producing a positive correlation between the theoretical analysis and the experimental results, leading to a successful proof of concept for a full scale test.