The goal of my Moon lander guidance software series is to learn and gain some experience with an end-to-end aerospace software project, especially on the topic of GNC. I have already written a few articles sharing my findings: for instance, this one about guidance. Today I want to talk about control. I will use the engine gimbal controller of my Moon lander1 project to explain how to design, tune and validate a PID controller. Read the 2049 words...

As part of my Moon lander guidance software, I am making several small prototypes for each subsystems, in order to test ideas, learn and choose the best option. While I progress on the overall project, I have already learned a lot of things and wanted to share some of them. In this article, I will talk about how to control the altitude and vertical velocity of a spacecraft in order to guide it to a soft landing. Read the 3922 words...

I have always struggled during my control theory classes, and almost failed one (out of the three I attended). With this history, some people would have developed a hatred for this subject, but I personally felt in love with it: I have always found it magical to be able to control physical things with software. I love making a pile of silicon1 do things by itself, and developing control algorithms makes it possible to build robots and other automated machines. Read the 2525 words...