Small Satellite Research Laboratory

MEMESat-1

In Collaboration with UGA SSRL MEMESat-1 Mission Team

The Mission for Education and Multimedia Engagement Satellite (MEMESat-1) is a low-budget 2U CubeSat under development by the University of Georgia Small Satellite Research Laboratory. Once launched into LEO, the CubeSat will serve as an FM repeater for the Ham Radio community and will uplink and downlink user-submitted images.

Frame

Boardstack

Antenna

Passive Attitude Determination Control System

Contributions:
MEMESat-1 Program Manager (05/2025 - Present)

I direct a multidisciplinary team of 40 undergraduate students in developing a nanosatellite that provides amateur radio services as a digital repeater on the UHF band, capable of uplinking and downlinking user-submitted images. The nanosatellite launch, in collaboration with Blue Origin, is planned for Q1 2027. I apply systems engineering principles to oversee and determine the design, integration, and testing of ADCS, CDH, COMMS, EPS, and MECH subsystems, ensuring system functionality and mission success criteria are achieved. I manage the 3-year project schedule, $25,000 budget, and serve as the primary liaison to government and industry research partners.

Mechanical Engineer (10/2023 - 05/2025)

Alongside the MEMESat-1 Mechanical Team, I designed the Aluminum 6064-T6 nanosatellite frame, boardstack supports, and antenna using Autodesk Inventor. I adjusted the design following internal and industry project reviews and made continual improvements to accommodate and integrate hardware. I designed the satellite's Attitude Determination Control System (ADCS), which utilizes hysteresis rods and a permanent magnet to passively direct the satellite's antenna orthogonal to the Earth's surface. This system prevents the necessity for magnetorquers to be implemented, reducing overall power draw. Some of the continual improvements I was responsible for included redesigning the lid for the board of batteries and redesigning the fastener system to accommodate helicoils. Ansys Structural and Modal Simulations determined the the frame and boardstack design withstand expected inertial loads during launch.

MEMESat-1 Full System Thermal Analysis

Nesbit, Owen, et al., "Developing a Full System Thermal Analysis of a CubeSat to Design a Low-Cost Battery Heater System." Proceedings of the 39th Annual Small Satellite Conference, Salt Lake City, Utah, August 2025. https://digitalcommons.usu.edu/smallsat/2025/all2025/54/.

Thermal Desktop Model

The thermal model was generated in Thermal Desktop using finite difference solids and composite thermal properties to emulate complex hardware efficiently. Density multipliers are applied to each FDS to ensure correct mass distribution for accurate heat transfer. Complex geometry is emulated through combining FDS nodes. The thermophysical and optical properties of simplified solids represent their overall mass and surface area compositions, respectively. Attempts to import and mesh pre-existing CAD create radiation group conflicts. Employing local thermal modeling techniques, which involve detailed geometric and material property representations, is essential for predicting the thermal behavior of satellites.

Radiation Groups

Radiation groups differentiate which surfaces receive direct exposure to solar, albedo, and IR planetshine radiation. The two radiation groups in this model are External and Internal. External surfaces, which receive solar radiation, are only applied to the sides of components that are fully exposed to the sun. All covered surfaces are designated as Internal. Components that are partially exposed to the sun are divided into separate finite difference solids, allowing every surface of the CubeSat to have correctly defined radiation groups.

Orbital Parameters

Two case sets model the most and least amounts of heat the CubeSat could receive. The differences between these cases are determined by their orbital parameters and heating rates. All cases have orbits that are assumed to be circular based on LEO CubeSat's low level of eccentricity. Each case set utilizes a transient solution that runs the model for 5 orbits, allowing enough time to reach convergence. An additional steady-state solution is active to calculate the average temperatures up until the transient solution converges. Radks are applied to both internal and external groups, and a heat flux is applied as a heating rate to the external group.

Heating Rates

Power Dissipation is evaluated at a component level and derated to assign conservative and realistic heat loads to each board in the model. During the Hot Case, All MEMESat-1 electrical components are modeled as heat loads generating maximum expected power dissipation. During the cold case, all heat loads are inactive except for the Battery Heater. The battery heater was evaluated at various wattages to determine the necessary power input for the batteries to remain within their desired temperature range.

Cold Case Power Board Interface Solution

Cold Case Board of Batteries Solution

Plotting the thermal response of each component over the satellite’s orbital period produces curves where each line represents the temperature evolution at a specific node in the finite difference model. The model identified that the internal satellite hardware is most likely to encounter a maximum temperature of 57°C and a minimum temperature of -4°C. The temperature maximum occurs at the sunward-facing point of the orbit, when the satellite is in direct sunlight and heat accumulates across its exposed surfaces, and the minimum occurs during eclipse, when the satellite is in Earth’s shadow and loses heat rapidly to deep space. While all components remain within operational limits, a mini heat sink will be added to the MPPT1 to provide an added safety margin and prevent potential overheating. The MEMESat-1 power budget prevents any increase in heater wattage in the current power configuration. Controls to modulate heater power supply and inactivate non-essential electronics during the orbit’s eclipse will be explored to test if the batteries could be supplied with more heat, when necessary, without limiting payload functionality. Otherwise, additional battery capacity could be integrated into the satellite to support higher power draw during eclipse periods, when the solar panels are not generating sufficient energy.

I developed a CubeSat thermal modelling guide for the UGA Small Satellite Laboratory to retain the knowledge I learned and shift the thermal modelling responsibility to other members of the MEMESat-1 Mechanical Team as I transitioned to the Mission Program Manager role.

Miscellaneous Projects

CNC Mill

In preparation to machine the MEMESat-1 nanosatellite frame, I learned Fusion 360 CAM and to use a Tormach 1100M to machine parts.

Thermal Vacuum Chamber CAD

To assist graduate research designing a new cooling system for the SSRL TVAC, I used Inventor to model the system and provide the graduate researchers with precise dimensions.

6U CubeSat Frame CAD

I created a conceptual design for a 6U CubeSat frame to meet NASA mechanical specifications.

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