Case Study
Challenges
Rocket science is already complex, and that is only getting the launch vehicle off the ground. Now try landing a spacecraft on a moving, rotating, debris expelling object to collect a sample while maintaining spacecraft communication and preventing damage to sensors f rom solar radiation. That was the challenge of NASA’s OSIRIS-REx mission. To prepare for the mission, Lockheed Martin Space (LMS) sequenced about one week of mission-time operations and simulated those operations on their testbed. Each test involved extensive manual operations, limiting the team’s ability to respond to a change in requirements and mission parameters. One week of simulated mission activity equaled one day of real-time simulation. For a ten-year mission, that would have meant mean months of simulating and analyzing data. Due to mission time constraints, the team was unable to simulate all possible variables and events. Any unplanned-for changes could have jeopardized the entire mission.
Engineering Solution
Lockheed Martin Space (LMS) developed a Model-Based Systems Engineering (MBSE) architecture to represent the spacecraft and the mission. To replicate and analyze the variables of space, they utilized mission simulation software. However, there was no bridge connecting the MBSE architecture to the simulations.
Utilizing ModelCenter MBSE, LMS was able to connect their MBSE models to the simulation tools. The system model captures mission and simulation parame-ters and thermal constraints. The parame-ter and constraints are time-stepped through a simulation that models the spacecraft’s orientation and trajectory concerning the Sun, Earth, Moon, and other bodies in the solar system. ModelCenter will evaluate the results f rom the simulation to ensure adherence to the mission constraints.