Surveyor spacecraft addon for Orbiter

An Orbiter addon that demonstrates the Surveyor lunar probe with a functioning landing autopilot

Building and running

1. Download/Install Orbiter from http://orbit.medphys.ucl.ac.uk/
2. Install Visual Studio 2019
3. Install Rust using rustup (https://rustup.rs)
4. Install the win32 target by running rustup target add i686-pc-windows-msvc
5. Build the project by running cargo build in the project root
6. Copy the target/i686-pc-windows-msvc/debug/Surveyor.dll to the <OrbiterPath>/Modules
7. Copy the files under the Scenarios, Meshes and Textures folders into the corresponding folders in the Orbiter install directory
8. Open Orbiter and run the "SurveyorTerminalDescent" scenario

Descent Guidance

The descent guidance in this addon is implemented based on the descriptions in the following papers/reports:

• Surveyor Mission Report - Part 1, Page 60
• Surveyor III Mission Report - Part 1, Page 40
• Surveyor Spacecraft Automatic Landing System by Sam W, Thurman
• Design Considerations for Surveyor Guidance by R.K. Cheng, C.M. Meredith, and D.A. Conrad
• Surveyor Terminal Guidance by R.K. Cheng

The "descent contour" was approximated from the plots in the above reports.

Acknowledgements

Big thanks to Harish Saranathan for clearing up some of my questions about attitude control. He has made his own version of the Surveyor descent guidance algorithm in C++ which can be found here: https://github.com/harishsaranathan/SurveyorAutopilotForOrbiterSpaceFlightSimulator.