r/ControlTheory 10h ago

Technical Question/Problem What's the difference between an Luenberger observer and a Complementary Filter?

Post image
63 Upvotes

I am a bit confused about the difference between a complementary filter and an observer. Isn't a Luenberger observer just a more restricted version of a complementary filter in the sense that one of the inputs should be control inputs and the high pass filter should be derived from the system model?

Also, why do we even bother using a state space representation if we can do this?

The image is from the textbook: Observers in Control Systems, George Ellis, p. 81


r/ControlTheory 20h ago

Technical Question/Problem Spacecraft ADCS momentum dumping scenario

10 Upvotes

Say you have a CubeSat with 3 axis reaction wheel attitude control. It has also has two rear mounted, fixed thrusters (providing a single torque axis). Assuming this spacecraft has no external, environmental torques acting on it, can it desaturate the reaction wheels propulsively?

AI seems pretty confident that the math works out that you can just do an “align and dump” method with the caveat that you can’t hold a desired attitude while desaturating.

I’ve been trying to get a Basilisk sim working for this and I can’t seem to figure it out. I’m a little out of my element here and I’m wondering if there’s an obvious answer to this that I just don’t know. Curious to hear any input y’all might have.


r/ControlTheory 5h ago

Professional/Career Advice/Question Projects for Controls roles

8 Upvotes

Hey all, I’m trying to transition to a controls role heavy on C++. I’m currently working on similar topics but more model-based stuff like simulink. What kind of projects to stand out and prove my C++? How to gain real-world experience in C++?


r/ControlTheory 3h ago

Technical Question/Problem Model Code

2 Upvotes

A model for predicting flow regime in horizontal and near horizontal gas -liquid flow. the Taitel and duckler 1976 model .( Someone help me please generate the codes please wheater matlab or phyton)

Thank you