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One can access the linkage simulation here.

Variable Stroke Mechanism Prototype

To validate that the variable stroke mechanism worked we built a prototype out of and FR4 and lexan. We chose to make the links an intend to construct much of our robot out of FR4, a glass reinforced epoxy laminate, because FR4 has a high specific strength and is quite cheap. We used bolts for the joints to enable the prototype to be easily disassembled, but intend to use 1/8" steel shaft with E-clips and washers for the final version. We actuated the input crank with a Polou 50:1 micro-HP motor and used a standard hobby servo control the amplitude. A video of the system is shown below(click on the picture)

Image Added

Sources:

1. A Variable Stroke Mechanism for Ornithopters
   
2. Fixed Frequency, Variable Amplitude (FiFVA) Actuation Systems for Micro Air Vehicles
3. Mechanisms and Mechanical Devices Sourcebook Third Edition by Neil Sclater and Nicholas P.Chironis
4. Zero Max Adjustable Speed Drive
5. Variable Stroke Engine

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