The Design and Optimization of a Small Cassegrain Telescope

Team Members

Problem Statement

Satellites are highly complex and resource-intensive systems that deliver essential data and images from space, requiring significant time, cost, and technical expertise to design and maintain. Developing a small-scale version of these systems provides a more accessible and cost-effective platform for methods to study performance and testing improvements.

Specifications and Requirements

The primary requirement for this optical device is that it is cost-effective and capable of imaging. In addition, the design must imitate a Cassegrain design method.

Value & Units	Description & Method of Evaluation
18.00 G	The optical structural assembly (OSA) shall maintain positive Margin of Safety (MoS) > 0.0 under Quasi-Static Limit Loads of Lateral. Method of evaluation: Perform simulation and a tensile test using the MTS machine. Apply strain gauges to check for permanent deformation. Inspect for cracks or visible failure.
180.00 Hz	The fixed-base fundamental natural frequencies of the stowed optical assembly. Method of evaluation: Simulation and perform an impact hammer test using accelerometers and a DAQ system to identify resonance peaks.
10.00 %	Reduction of part count to simplify assembly. Method of evaluation: Compare the part count with the previous year’s design iteration.
10.00 %	Achieve a 10% reduction in total structural weight (including lenses) from the initial CAD design while maintaining a factor of safety of 1.25 against yield. Method of evaluation: Compare the final assembly weight on a digital scale with initial NX mass-property estimates.
0.00039 in	Resolution of secondary mirror adjustment. Method of evaluation: Set up the optics and image a sample target located 72 inches away.
0.0039 in	The optical assembly shall maintain focus over an operational soak temperature of 122°F ±3.6°F for 60 minutes. Thermal expansion (CTE) induced defocus shall not exceed. Method of evaluation: Simulate the assembly and place it in an oven; use markers to detect any lens displacement.
12 G	The optical structural assembly (OSA) shall maintain a positive Margin of Safety (MoS) > 0.0 under Quasi-Static Limit Loads of 12G (Axial). Method of evaluation: Perform simulations and verify simulations through tests.
1.5 FS	Factor of safety against ultimate.
1.25 FS	Factor of safety against yield.
14 %	Reduction of obstruction of the primary lens.