Specifications

CT Corsair Final Report May 2, 2014
35
Figure 42: 3D Printed
Adjustable Lower Scissor Arm
8.4.3 Analysis Results
The FEA was completed using the aforementioned criteria. Using 9038 as the number of
elements in the mesh density resulted in a stress distribution shown in Figure 41. It can be clearly
seen that the member will fail at the bearing holes before any other member deformation. This
failure occurs at approximately 2400 N, or 540 lbs, for each upper scissor arm. The maximum
weight of the simulator with a pilot is approximately 1240 lbs, therefore each arm will have an
additional 126 lbs beyond the maximum weight that they can hold before failure occurs.
The results of the FEA allow the design, analysis, and manufacturing process of the lower scissor
arms to match the characteristics of the upper scissor arm. This will help to prevent over-
engineered components, thus saving money.
8.5 Lower Scissor Arm Design
8.5.1 Parametric Model Development
The parametric model of the simulator base was used to design the new
lower scissor arm with the criteria found through the analysis of the
upper scissor arm. An important design aspect of the arm includes the
lower tab coinciding with the shock absorbing spring. Each spring
bottoms out at 9.24” and is fully extended at 13.01” so each tab must
allow for the spring to fit comfortably within this range. The arm must
also allow for clearance above the existing induction motors, as well as
the proposed servo motors. In order to accommodate the length
requirements the team decided to utilize the 3D printer available on
campus and create an adjustable arm, seen in Figure 42. This arm
contained a threaded stud in the center allowing for length adjustments
which could tweak the overall size of the arm without wasting the raw material purchased by the
sponsor. The final lower scissor arm design is shown in Figure 43.
Figure 41. Stress distribution on upper scissor arm