Questions tagged [flight-control]

Systems and software used to control a space craft's trajectory.

Filter by
Sorted by
Tagged with
45
votes
3answers
7k views

Did a flight controller ever answer Flight with a no-go?

OK, all flight controllers, I'm going around the horn Retro? Go FIDO? Go Guidance? Go Control? Go TELCOM? Go GNC? Go EECOM? Go Surgeon? Go Are there any ...
17
votes
4answers
2k views

How were the pilots of the space shuttle able to operate the rudder after time in space?

I've just watched this video showing three astronauts who've returned from space. At around the 5:46 mark in the video we can see astronaut Chris Hadfield being carried out of the Soyuz capsule. I've ...
13
votes
3answers
2k views

Does this kill vehicle contains momentum wheels? Watch how it moves!

This comment below this answer about 'spacecraft' or at least 'craft' that can maneuver near the surface of low gravity bodies links to this video about Lockeed Martin's Multiple Kill Vehicle. If I ...
12
votes
1answer
3k views

How can a rocket go straight up after ignition? [duplicate]

We have seen during rocket launches that the rocket goes straight up after the launch clamps have disconnected. What ensures that it doesn't tilt because of the uneven mass distribution? How does a ...
11
votes
5answers
734 views

Is it possible to navigate space travel with no computer?

From launch to land could a person travel in space with only mechanical devices like a sextant? With enough experience what would be the minimum devices needed? Which vehicle currently would be easier ...
11
votes
0answers
506 views

Why are there advertisements in the Russian ISS flight control room?

I found a photograph of the Russian ISS flight control room: Source: NASA https://commons.wikimedia.org/wiki/File:Russian_ISS_Flight_Control_Room.jpg Below the large screen are several ...
8
votes
4answers
3k views

Why does spinning help stabilisation?

I don't really understand why do we use spin stabilisation for rocket launches? If I understand correctly, the idea is to make the rocket spin really fast so that any asymmetry in the thrust/...
8
votes
1answer
886 views

Machine Learning and Classical Navigation, Guidance and Control in Space Exploration

Due to the increasing availability of large quantities of data and computational power, machine learning (ML) is providing increasingly better results in various fields. Much research has been done on ...
7
votes
2answers
112 views

Implementing control system to track position and velocity references simultaneously

I've been trying to implement a PI (proportional-integral) controller to allow a launch vehicle to track 2 reference states simultaneous, namely position and velocity, so that the launch vehicle will ...
7
votes
0answers
511 views

How is retropropulsion by the Falcon 9 first stage being used to design retropropulsion entry on Mars?

Much has been made of how the reentry burns of Falcon 9 first stages occur at an altitude where the atmosphere is similar in density to the atmosphere of Mars, and so they demonstrate that supersonic ...
6
votes
1answer
75 views

Apollo CSM mass, inertia and RCS parameters?

Is there a document specifying the total mass, the 3-by-3 inertia tensor of the Apollo CSM assembly, as well as the geometry of the service module and command module RCS assemblies (in other words, ...
5
votes
3answers
1k views

Is aerodynamic lift ever useful in rocket flight?

When a rocket is traveling through an atmosphere, the component of the aerodynamic force in the direction of motion is called drag, and the component perpendicular to that is called lift. Usually a ...
5
votes
1answer
380 views

Apollo CSM thruster quad orientations vs LM

Can anyone explain to me the reasoning behind the differences in the placement and orientation of the thruster quad packages on the CSM and LM? On the CSM a quad is a + shape and are located in a ...
4
votes
4answers
339 views

Using what technology one can keep a spacecraft truly non rotating

Inspired by the question I thought maybe a photon thruster can be used for precisely giving thrust to maintain spacecraft attitude. But soon I realized that for high precision attitude control, one ...
4
votes
2answers
139 views

Can a spacecraft use an accelerometer to determine its orientation?

I know that almost every spacecraft uses a gyroscope to determine its orientation, but I don't know if an accelerometer could also be used in addition to a magnetometer to calculate it. I have been ...
4
votes
2answers
500 views

Does the Hubble telescope use a “simple” PID-controller for its pointing control system?

I am wondering whether the Hubble Space Telescope uses a "simple" PID controller like this: Or is it using another type of control system that may be much more complex?
4
votes
2answers
101 views

Apollo CSM RCS maximum number of simultaneously active engines?

Reading the RCS subsystem manual, it seems like each RCS quad of the Apollo SM consisted of four hypergolic engines. Am I correct in saying that all four engines of each of the four quads could be ...
4
votes
1answer
629 views

How to select/design a control algorithm for spacecraft attitude control?

Control algorithms are used on spacecraft to operate reaction wheels, RCS thrusters and other actuators. Since of the most common controllers I've come across are the PID and quaternion error command. ...
4
votes
1answer
155 views

Where are these historical IBM + Apollo related locations within NASA? What do these computers do?

In the Fortune Magazine video IBM's Moonshot: Past and Future with the notes BM’s John Kelly reflects on Apollo 11’s historic mission and looks forward to what future technology will accomplish. ...
4
votes
1answer
305 views

Controller to reaction wheel interface

A typical controller generally gives control torques which should be applied about the axis of a satellite. How exactly is this torque applied using a reaction wheel? For example if control torques ...
4
votes
1answer
123 views

Among Quantitative Feedback Theory and H infinity, which one is preferred for robust control of satellites esp. small satellites? And why?

I am interested in designing a robust controller for a small satellite with antenna, sloshing propellant and flexible panels on board. I am mostly interested in achieving arcsec precision pointing ...
4
votes
0answers
372 views

Why would someone use Modified Rodrigues Parameters over Quaternions for spacecraft attitude estimation? And vice versa?

I see quite some papers on spacecraft attitude determination and control, that rely on quaternions. While some others rely on MRPs. The advantage that I see so far is that... for quaternions, the ...
3
votes
2answers
293 views

SpaceX stage 1 reentry control?

In watching today's BulgariaSat-1 broadcast: It was mentioned that the drone ship had acquired the 1st stage as it was returning. I had always been under the ...
3
votes
1answer
444 views

What exactly is rhumb-line control in the context of a launch trajectory?

The conference paper SS-520 Nano satellite launcher and its flight result SSC18-IX-03 from the 32nd Annual AIAA/USU Conference on Small Satellites linked in this answer describes the use of rhumb-line ...
2
votes
1answer
111 views

What are the top most used satellite control system, flight dynamics solution at the moment ? Approx costs?

I am looking for a list of top most used satellite control systems, flight dynamics solutions by space agencies, private companies etc. the moment? How much do they cost approx for use by 1 person? Is ...
2
votes
2answers
562 views

Rocket drag and lift based on flight direction - in which frame of reference?

Drag is aerodynamic force component parallel to the direction of motion. Lift is aerodynamic force component perpendicular to the direction of motion. Direction of motion with respect to what? 1) ...
2
votes
1answer
76 views

Satellite mission design/performance requirements to attitude/orbit control design specifications

Are there any good sources that discuss: the steps involved in deriving attitude/orbit control design specifications, from satellite mission design/performance requirements?
1
vote
1answer
115 views

An program that automatically generates a rocket guidance system?

This is for a liquid propelled rocket that launches from earth. It could also perhaps be used for orbital maneuvers and landing on the Moon (not mars or earth). The inputs for such a program would ...
1
vote
2answers
230 views

How much can static cling be used to move things in space? Tractor Beam

Can static cling occurs in space? Can a static charge be amplified laterally to move objects in space similar to Star Trek's tractor beam? Can a static charge could be carried by a sustained particle ...
1
vote
1answer
70 views

How do small, spin stabilized launchers follow a rhumb line?

This concise answer to What exactly is rhumb-line control in the context of a launch trajectory? explains the concept in the context of the SS-520 nanosatellite launch vehicle (which "doesn't exist"). ...
1
vote
0answers
128 views

Analyzing Amateur Rocket Stability and Range Safety

I am working with a university bunch of other university students on building a very large amateur rocket. Our objective with this rocket is just to go very high, with no significant payload or ...
1
vote
0answers
76 views

Linear Control Lock?

Assume a spacecraft with a less-than-perfect maneuvering thruster configuration such that in a particular attitude while attempting to dock, the thrusters will not allow translation along a particular ...
0
votes
0answers
56 views

How to filter a white noise or random noise in Matlab Simulink?

I am working on a sun-synchronous satellite Simulink model wich determines its attitude from a Sun sensor and a star sensor whom measure the sun and star direction in the satellite body reference ...
0
votes
0answers
331 views

Avionics Systems on board Falcon 9 (Reusable)

What kind of control systems are active and how do they function on board a Falcon 9 booster while it's landing ?
0
votes
0answers
112 views

Will there be torques on spacecraft due to interaction of magnetic torquer with the residual magnetic field of the spacecraft?

Assuming the magnetorquer and the field generating electronics are both rigidly fixed to the spacecraft cube. Reference to any supporting papers/articles would be great. Thanks. Would the residual ...