Reusable Lunar Surface Access Vehicle
With a growing curiosity in colonizing Mars and the Moon, our team took up the challenge set by the American Institute of Aeronautics and Astronautics (AIAA) to design a Reusable Lunar Surface Access Vehicle (RLSAV).
Due to a four month time line, the focus of the challenge was narrowed, and the following assumptions were declared:
Once the project was clearly defined, a Work Breakdown Structure was created, and tasks were assigned based on individuals’ strengths and experiences.
My role was primarily in Orbital Dynamics, calculating the retrograde burns for a safe landing, amount of fuel required to land and take off, length of the mission, and determining landing sites on the moon.
We consulted Dr. Enright throughout our project on information we were not familiar with.
The empty structure should weigh around 3,500 kg and will be constructed out of composites, aluminum and titanium.
To the left is an ideal model to show space holders of various components and a rough shape of the spacecraft.
The Near Rectilinear Halo Orbit is a dynamic orbit with varying dimensions and period, making the parameters for landing slightly different depending on the status of the orbit for the Gateway.
For ΔV and fuel requirements, we took the Orbit at its maximum size with a periapsis of 4500km, period of 6.993 days and velocity of 1.4445 km/s.
The retrograde burns would take four stages to complete and would require a net change of velocity of 2.6919 km/s spanning over 12.504 hours from gateway to landing on surface.
The astronauts would have to wait 155.328 hours on surface before the gateway is in distance to begin take off and prograde ascend.
The vehicle will be able to switch between cargo or crew mode at the Lunar Gateway.
The cargo mode can carry 15,000 kg to the lunar surface and bring back 10,000 kg to the Gateway.
The crew mode can sustain a crew of four for 24 hours with the on board supplies such as food, water, oxygen, waste disposal system and etc.
In order to control the spacecraft’s temperature and shield the cargo from radiation from the sun, the vehicle will be lined with FPA-35, Carbonfiber, D10-1 and have an anodized black surface.
An active thermal control system will also be implemented to regulate the temperature.
For Attitude Determination and Control, the spacecraft is equipped with 3 star trackers, 3 sun sensors, 2 inertial momentum units to correctly know the orientation of the spacecraft.
The spacecraft is then equipped with 2 types of thruster clusters to make maneuvers in flight. The built in redundancy in the design of the cluster allows for complete control even after the failure of two thrusters.
The Telemetry, Tracking and Control System utilizes parabolic antennas with NASA’s deep space network to communicate with Earth, and bi-conical horn antennas to relay information back to the lunar gateway.
The spacecraft is equipped with an alkaline fuel cell to meet the spacecraft’s need for a constant and regulated power demand.
The benefit of a fuel cell over a solar array is that it can provide power during an eclipse, and the system weighs less overall.
Four gimbaled RL10 rocket engines are used to land propulsively and take off from the lunar surface.
The rockets are supplied with 40,000 kg of fuel to ensure safe return from surface to the gateway.