Specifications

CT Corsair Final Report May 2, 2014
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by linear relationships with each other, forcing the development of two CAD models. The first
CAD model was of the vertical motion profile and modeled the relationship between the cam,
pushrod, and simulator platform. The second CAD model was of the pitch/roll motion profile
and modeled the relationship between the cam, pushrod, and simulator platform. Each of the
models were used to produce the graphs in Figure 17 and Figure 21, which depict the nonlinear
relation between the rotation of the cam and all other dependent angles. MATLAB was utilized
to curve fit the data and produce functions relating the angle of rotation of the cam to the other
dependent angles.
The next step that was undertaken was to experimentally derive the spring constant of the
restoring spring. To derive the spring constant, an experiment was conducted in which varying
weights were hung from the edge of the simulator, Figure 13, and the vertical displacement of
the platform of the simulator was measured. The intention behind hanging weights from the
simulator was to replace the force of the pushrod with a measureable force, a hung weight. Then
the displacement verses force data was graphed and produced Figure 14. The graph revealed a
linear relationship between force and displacement allowing the spring equation to be
used and the spring constant to be defined as 189000 N/m.
Once the motion profiles, free body diagrams, equations of motion, CAD models, dependent
angle relationships, and spring constant were determined a MATLAB program was written to
combine all of the data. The MATLAB program created two torque curves, one for the vertical
lift case, Figure 18, and one for the pitch/roll case, Figure 22. Analysis of the two different plots
revealed the maximum torque requirement to be 3500 in-lbs. Also the data was utilized to
calculate the maximum angular velocity of the motor to be 85 RPM.
The motor requirements were validated in three separate ways. The first validation was done by a
Moog Motor Corporation product application manger of their simulation division. The product
application manager had designed a cam driven simulator in the past that was comparable in
weight and size. In the design of the simulator Moog had utilized servo motors that were rated at
3500 in-lbs. Therefore, since the two simulators are comparable in size and the derived torque
requirements match, the torque requirements are validated. The second validation was done by
the COO of Environmental Tectonic Corporation. The 3500 in-lbs. torque requirement was
presented to the COO who verified that the torque requirement was reasonable. The final
validation for the torque requirement was done by comparing the torque requirement of the old
motor to that of the derived torque requirement. The old torque output was 1212 in-lbs. which is
less than half of the new torque output. Therefore, the new torque requirement which is more
than double the previous torque requirement insures that the simulator will function.
After validation, the motor requirements were presented to Moog Motor Corporation who then
presented the G-5-M8 motor as the correct motor for the application. Then Neugart was
presented the requirement of needing a 20:1 gearbox with the loading scenarios of a cam driven
simulator. Neugart presented the WPLPE120-20 as the correct gearbox for the application.
The second deliverable was to redesign the lower scissor arm so that it was not overbuilt and did
not collide with the base. Redesign of the lower scissor arm began by drawing the free body