Projects / Duke Solar Sail Team

Solar Sail L1 Project

A solar sail is a light, reflective membrane spacecraft pushed by sunlight. As photons reflect off the sail they transfer momentum, producing a small thrust without any propellant.

Role: Electrical Lead, Frame Modal
Period: Summer 2026 – present
Competition: Earth Cup, Race 1
Status: Advanced to STEP 2

Solar sail mission schematic showing launch, deployment, de-tumbling, downlink communication and orbital decay

Background

Earth Cup and our goal

Duke's solar sail team competes in Earth Cup, an international engineering competition that advances solar sail technology. In Race 1, teams design and build small sailcraft for low Earth orbit that demonstrate spacecraft control, communications and solar radiation pressure.

After teams complete the STEP 2 build and testing requirements, Earth Cup plans to launch all participating teams' sails together aboard a Rocket Lab Electron rocket.

Our goal is to launch our sail into very low Earth orbit (VLEO), stay in orbit as long as possible and downlink inertial and telemetry data. The competition supports work on future space exploration and on space-based sunshades as one possible way to reduce Earth's warming. Earth Cup defines a standard for these membrane satellites, called MemSats, in its MemSat specification.

Front view CAD of the hexagonal sail with corner node housings — **Fig. 1**Sail CAD, front view.

Angled CAD view of the hexagonal sail membrane and frame — **Fig. 2**Sail CAD, angled view.

Summer 2026

Power and sensors

The team started in summer 2026 with the preliminary design review of our prototype sail. For STEP 1, each team wrote and presented a technical white paper to the judges. Read our white paper.

I led the power and sensors subteam. I:

researched lightweight solar power using GaAs photovoltaic cells
researched power storage with ultrathin LiPo pouch cells
calculated the spacecraft power budget, with a focus on power-to-mass ratio
defined operating modes based on orbit timing and conditions
designed the power subsystem's wiring architecture in KiCad
evaluated onboard sensors for temperature and motion monitoring

Electrical subsystem architecture diagram linking solar cells, regulator, battery, microcontroller and sensors — **Fig. 3**Electrical subsystem architecture.

Power budget table listing each subsystem, component, power draw and purpose — **Fig. 4**Power budget by subsystem.

Operating modes table listing active components, power draw and timing for each mode — **Fig. 5**Operating modes.

KiCad schematic of the power subsystem — **Fig. 6**Power subsystem schematic in KiCad.

System diagram connecting orbital dynamics, communications, structure, power and thermal subsystems — **Fig. 7**Subsystem overview.

Fall 2026

Frame and node analysis

Back on campus, the team turned to the sail's physical architecture. With the electrical architecture settled, I moved to frame modal and node analysis. So far I have:

run FEA on the sail frame to find its natural frequency and deflection
compared the FEA results against a physical frame model we tested for natural frequency and deflection
researched node designs for the frame
designed a flange-based node in SOLIDWORKS and Onshape that supports thread-skipping during transit

Early in the school year, our STEP 1 submission was approved and we advanced to STEP 2, where we are now building the solar sail in-house.

FEA result of the hexagonal sail frame with a color scale for displacement — **Fig. 8**FEA of the sail frame.

CAD of the compliance node prototype — **Fig. 9**Prototype: compliance node. Prioritizes axial stress, with no thread-skipping.

CAD of the flange node — **Fig. 10**Current: flange node. Internal spheres allow thread-skipping between sails, as the MemSat standard requires.

CAD of the plunger node — **Fig. 11**Current: plunger node. Handles axial and transverse stress; spring plungers sit in the holes in the final design.

VideoNode and frame work.

Links

Earth Cup website ↗