Design and Analysis of the Drop Test Vehicle for the Mars Exploration Rover Parachute Structural Tests

The 2003 Mars Exploration Rover mission will deliver two advanced rovers to the surface of Mars in early 2004. The Mars Pathfinder-heritage entry, descent, and landing system relies upon a supersonic disk-gap-band parachute deceleration system. A low Earth altitude structural qualification test of this system was conducted in May 2002. This paper describes the design and development of the Drop Test Vehicle utilized in this test. The dynamic response of the test vehicle to large uncertainties in initial conditions was improved over previous designs by increasing the aerodynamic stiffness and damping, while reducing the pitch and yaw moments of inertia. This improved design had four large aerodynamic fins, a short cylindrical body, and a massive conical fore-body nose. A six degree-of-freedom trajectory simulation was developed to verify the performance of the system. The robustness of the design to offnominal conditions was demonstrated through a Monte Carlo analysis. Reconstructed test data showed very good agreement with pre-flight simulation predictions of vehicle dynamics.